246 results on '"ÁCIDOS"'
Search Results
2. Grovfodrets betydelse i foderstaten för hälsan hos mjölkkor
- Author
-
Nilsson, Louise and Nilsson, Louise
- Abstract
För att tillgodose energibehovet för en högproducerande mjölkko utgörs foderstaten av grovfoder tillsammans med en andel kraftfoder. Nötkreatur är anpassade att bryta ner och smälta grovfoder och det stimulerar idissling och salivproduktion som hjälper till att bibehålla stabilt pH i våmmen vilket skapar en god våmmiljö för mikroberna. Kraftfoder med mycket stärkelse har däremot visat sig kunna ge problem då fermentation av stärkelsen bidrar till lågt pH i våmmen och kan rubba mikrobiotan. Syftet med denna litteraturstudie är att undersöka grovfodrets betydelse i foderstaten för mjölkkors hälsa och lyfta fram vilka för- och nackdelar det finns med utfodring av olika andelar grovfoder och kraftfoder till mjölkkor. Det har visat sig finnas betydligt fler fördelar med utfodring av hög andel grovfoder med avseende på hälsan än hög andel kraftfoder och det verkar finnas ett samband mellan djurets hälsa och mikrobiotans aktivitet och population. Eftersom gräs är kons naturliga föda och deras digestionsorgan och fodersmältning är anpassad att smälta foder med mycket fibrer, har en foderstat innehållande grovfoder positiva effekter på våmmens mikrobiota. En ko som däremot får i sig mycket stärkelserikt kraftfoder under en kortare tid kan drabbas av metaboliska störningar såsom acidos och fång på grund av förändringar i våmmens mikrobiota orsakat av lågt pH. Det är därför viktigt att tillgodose nötkreaturens behov av grovfoder då det har en betydande roll för djurets hälsa och fysiologiska funktioner., To meet the energy requirement of a high-producing dairy cow, the diet consist of roughage with a proportion of concentrate. Cows are adapted to break down and digest roughage and it stimulates rumination and saliva production which helps maintain a stable pH in the rumen and creates a good rumen environment for the microbes. Concentrate with a lot of starch, on the other hand, has been shown to cause problems as the fermentation of the starch contributes to a low pH in the rumen and can disturb the microbiota. The purpose of this literature study is to investigate the importance of roughage in the diet for the health of dairy cows and to highlight the advantages and disadvantages of feeding different proportions of roughage and concentrate to dairy cows. It has been shown that there are more health benefits from feeding a higher proportion of roughage than a higher proportion of concentrate and there seems to be a connection between the health of the animal and the activity and population of the rumen microbiota. Since grass is the cow’s natural feed and their digestive system is adapted to digest fibrous forage, a diet containing roughage has positive effects on the rumen microbiota. In contrast, a cow that ingests concentrates with high starch content for a short period of time may suffer from metabolic disorders such as acidosis and laminitis due to changes in the rumen microbiota caused by low pH. It is therefore important to meet the cow’s need for roughage as it has an important role for the animal’s health and physiological functions.
- Published
- 2024
3. Tratamiento de las estenosis de píloro por gastritis corrosivas
- Author
-
Julio C Barani
- Subjects
ingestión ,ácidos ,lesiones ,gastritis ,Surgery ,RD1-811 - Abstract
Presentado en sesión de 13 de julio de 1955
- Published
- 2020
4. Directivas generales para el tratamiento de las esofagitis corrosivas y las estenosis cicatrizales
- Author
-
Julio C. Barani
- Subjects
esófago ,tratamiento quirúrgico ,ingestión ,ácidos ,endoscop´´ia ,Surgery ,RD1-811 - Abstract
Presentado en sesión de 4 de abril de 1951
- Published
- 2020
5. Substitution of a high percentage of fishmeal for silages of fishery by-products in extruded diets for Clarias gariepinus.
- Author
-
Llanes, J. and Parisi, Giuliana
- Subjects
- *
CLARIAS gariepinus , *FISH waste , *FISH meal , *FISHERY products , *DIET , *SILAGE - Abstract
A total of 270 fingerlings (10.7 ± 0.06 g of average weight) were randomly distributed in three treatments with three repetitions, according to a completely randomized design, to evaluate the total substitution of a high fishmeal percentage for silages of fishery by-products in extruded diets for Clarias gariepinus. The treatments were catfish fingerling feed with 25 % of fish meal (control) and two alternative diets, with 10% (dry basis) of silage: one prepared with 98 % of sulfuric acid, and the other with formic acid. Animals were fed for 60 d. No differences were found (P> 0.05) in the final weights (66.63, 66.27 and 70.71 g) and food conversion (1.18, 1.18 and 1.15). However, there were differences for protein efficiency between the diet with fishmeal (2.34) and the silage of fishery products (3.09 and 3.18). Survival was excellent in all treatments (> 96.66%). The economic analysis showed that the profits with silage (US $ 2534.22 and 2430.05/t) were superior to control (US $ 1689.44/t). It is concluded that chemical silages of fishery by-products can replace a high percentage of fishmeal in extruded diets for Clarias gariepinus fingerlings with a positive economic effect, by reducing the importation of fishmeal. [ABSTRACT FROM AUTHOR]
- Published
- 2021
6. Resistencia química de concretos de activación alcalina ceniza volante/ escoria: Sulfatos y ácidos
- Author
-
William Gustavo Valencia-Saavedra, Daniela Eugenia Angulo-Ramírez, and Ruby Mejia de Gutiérrez
- Subjects
ácidos ,ceniza volante ,geopolimeros ,propiedades mecánicas ,resistencia química ,sulfatos ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Technology (General) ,T1-995 - Abstract
Una de las características más importantes del concreto en adición a sus propiedades mecánicas es su durabilidad, que se asocia con la vida en servicio de las estructuras expuestas a ciertas condiciones o ambientes; esta propiedad es requerida para definir los potenciales campos de aplicación y facilitar la comercialización de nuevos materiales cementantes. En este estudio, se evaluó la resistencia química de un concreto de activación alcalina basado en cenizas volantes (CV) y escoria de alto horno (ESC) en relación 80/20; como material de referencia se utilizó un concreto a base de cemento convencional (OPC). La resistencia a la compresión del concreto Geo CV /ESC a 28 días de curado normal fue de 42,9 MPa, 26% superior a la reportada por el concreto OPC. Geo CV/ESC expuesto a sulfatos hasta la edad de 180 días no muestra expansión y la pérdida de resistencia a la compresión no es significativa (2%) en comparación con OPC (39%). En el caso de la exposición a los ácidos, Geo CV/ESC presenta una pérdida de resistencia del 39% y OPC de hasta el 80%. Estas características demuestran una mayor resistencia química del concreto de activación alcalina y por tanto su potencial uso en ambientes agresivos.
- Published
- 2018
- Full Text
- View/download PDF
7. Biosíntesis de nanopartículas de plata a partir de hongos rizosféricos y su inmovilización en una fibra natural para el control in vitro de la bacteria fitopatógena (Pectobacterium carotovorum)
- Author
-
Beltrán Pineda, Mayra Eleonora, Sierra Avila, Cesar Augusto, Lizarazo Forero, Luz Marina, Grupo de investigación en macromoléculas, Grupo de investigación Biología ambiental, Beltrán Pineda, Mayra Eleonora [0000-0002-0451-2535], Beltrán Pineda, Mayra Eleonora [https://scienti.minciencias.gov.co/cvlac/visualizador/generarCurriculoCv.do?cod_rh=0000508136], and Beltrán Pineda, Mayra Eleonora [https://scholar.google.com/citations?user=ZRzS9t4AAAAJ&hl=es]
- Subjects
Bacteria ,Agricultura de precisión ,Estereoisomerismo ,Stereoisomerism ,Bioprocesos ,572 - Bioquímica [570 - Biología] ,Fusarium oxysporum ,Pectobacterium carotovorum ,Nanopartículas de plata ,Ácidos ,Bacterias ,Acids ,Micosíntesis ,Solanum tuberosum - Abstract
ilustraciones, fotografías En esta investigación inicialmente se realizó un estudio de bioprospección para seleccionar hongos rizosféricos de cultivos de papa, hongos promisorios para la síntesis de AgNp´s con acción antibacterial frente a Pectobacterium carotovorum, agente fitopatógeno de papa de difícil manejo por técnicas convencionales. Se aislaron cinco hongos de las especies Penicillium simplicissimum, Aspergillus niger y Fusarium oxysporum que produjeron AgNp´s esféricas de tamaños entre 15 y 45 nm, las cuales presentaron acción antibacterial frente al fitopatógeno. Empleándose a Fusarium oxysporum se encontró que al usar una solución de AgNO3 3mM, pH de 10, y 27 °C/24 h se obtiene el mayor rendimiento en la síntesis de AgNp´s. Posteriormente, estas nanopartículas fueron caracterizadas por TEM, FTIR, XRD, DLS. PI y potencial Z, tras lo cual su poder antibacterial frente al fitopatógeno Pectobacterium carotovorum fue estudiado, encontrándose zonas de inhibición de crecimiento de hasta 11,3 mm de diámetro cuando se emplea una dosis de 100 ppm y una MIC de 25 y 50 ppm, determinada por micro y macrodilución respectivamente. También se realizaron estudios a nivel del sustrato vegetal, evidenciándose un efecto protector sobre el tubérculo cuando se aplica una dosis de 100 ppm de AgNp´s sobre el tejido a manera de tratamiento preventivo. Posteriormente y para limitar la absorción de las nanopartículas en el tubérculo se realizaron pruebas de inmovilización de las AgNp´s sobre fibras de algodón quirúrgico por dos metodologías (cationización y reducción bioquímica in situ), obteniéndose dos tipos de fibras denominadas A-AgNp´s-C y A-AgNp´s-RBi. Fibras que mostraron zonas de inhibición de crecimiento del Pectobacterium carotovorum, con una disminución en los recuentos bacterianos a las 24 horas e inhibición de crecimiento a las 48 horas. Donde las pruebas de reuso de estas fibras con nanopartículas mostraron que los dos tipos fibras pueden tener hasta tres usos sucesivos sin perder su efectividad, independientemente del método de modificación empleado. Adicionalmente, es importante resaltar que las pruebas de retención de las AgNp´s indicaron que estas permanecen adheridas a las fibras A-AgNp´s-C y a las fibras A-AgNp´s-RBi después de dos y tres lavados sucesivos, respectivamente. Finalmente, las AgNp´s biosintetizadas se adhirieron a fibras de fique por cationización con el objetivo de obtener sacos antibacteriales de 10 x 12 cm, los cuales en pruebas in vivo presentaron tan solo un 7,8 % de afectación, mientras que tubérculos almacenados en un saco tradicional tuvieron una afectación del 25%. Por lo tanto, el empleo de hongos rizosféricos para la síntesis de AgNp´s con acción nanopesticida frente al fitopatógeno P. carotovorum y su inmovilización en fibras naturales, permitirá el desarrollo de una aplicación nanobiotecnológica en el campo de embalajes para el almacenamiento de papa, con posibilidades de escalamiento, lo que aunará en la implementación de prácticas de agricultura de precisión. (Texto tomado de la fuente) In this research, a bioprospecting study was initially carried out to select rhizospheric fungi from potato crops, promising fungi for the synthesis of AgNPs with an antibacterial action against Pectobacterium carotovorum, a potato phytopathogenic agent that is difficult to manage by conventional techniques. Five fungi of Penicillium simplicissimum, Aspergillus niger, and Fusarium oxysporum that produce spherical AgNPs between 15 and 45 nm in size were isolated and showed antibacterial action against the phytopathogen. Using Fusarium oxysporum, it was found that using a solution of AgNO3 3mM, pH 10, and 27 °C/24 h obtained the highest yield in AgNPs synthesis. Subsequently, these nanoparticles were characterized by TEM, FTIR, XRD, DLS, PI and Z-potential, after which their antibacterial power against the phytopathogen Pectobacterium carotovorum was studied, finding growth inhibition zones up to 11.3 mm in diameter when using a dose of 100 ppm and a MIC of 25 and 50 ppm, determined by micro and macrodilution, respectively. Studies were also carried out at the plant substrate level, showing a protective effect on the tuber when a dose of 100 ppm of AgNPs was applied to the tissue as a preventive treatment. Subsequently, and to limit the absorption of the nanoparticles in the tubercle, immobilization tests of AgNPs on surgical cotton fibers were carried out by two methodologies (cationization and in situ biochemical reduction), obtaining two types of fibers called A-AgNPs-C and A-AgNPs-RBi. These fibers showed growth inhibition zones of Pectobacterium carotovorum, with a decrease in bacterial counts at 24 hours and growth inhibition at 48 hours. The reuse tests of these fibers with nanoparticles showed that the two types of fibers could have up to three successive uses without losing their effectiveness, regardless of the modification method used. Additionally, it is important to highlight that the retention tests of the AgNPs indicated that they remain attached to the A-AgNPs-C and A-AgNPs-RBi fibers after two and three successive washes, respectively. Finally, the biosynthesized AgNPs were adhered to fique fibers by cationization to obtain antibacterial 10 x 12 cm sacks, which in in vivo tests showed only 7.8% of affectation, while tubers stored in a traditional sack had an affectation of 25%. The use of rhizospheric fungi for the synthesis of AgNPs with nanopesticidal action against the phytopathogen P. carotovorum and their immobilization in natural fibers will allow the development of a nanobiotechnological application in the field of potato storage packaging, with the possibility of scaling up, which will contribute to the implementation of precision agriculture practices. Gobernación de Boyacá mediante la convocatoria 733 de 2015. Formación de capital humano de alto nivel. Doctorado Nacional. Doctorado Doctor en Biotecnología Bioprocesos
- Published
- 2023
8. Leptospira: revisión del agente causal de una enfermedad zoonótica
- Author
-
Luzlady Chavarría Joya and Daniela Lara Gutiérrez
- Subjects
zoonosis ,ácidos ,serovares ,Medicine - Abstract
La leptospirosis es una enfermedad zoonótica reemergente, tiene comportamiento endémico y es de gran im-portancia en la salud pública a nivel mundial. Su prevalencia es alta en países tropicales y subtropicales, pero presenta mayor incidencia en lugares donde es frecuente la agricultura, la manufactura de productos animales, la silvicultura, la ganadería, entre otros.Esta patología tiene un porcentaje elevado de mortalidad y aunque generalmente es subclínica, puede producir síntomas que van desde un resfriado común hasta fiebre hemorrágica, es por esto que se confunde fácilmente con otras patologías evitando que sea tratada oportunamente. Su forma crónica puede generar alteraciones sistémicas a nivel hepático, renal y pulmonar. El diagnóstico es muy complejo por las características morfológicas de la Leptospira, por lo cual su identificación se realiza mediante dos tipos de ensayos: serológicos y moleculares. El objetivo de este artículo es realizar una revisión bibliográfica de esta patología, comprendiendo: morfología, clasificación genómica, patogenia, epidemiología, tratamiento y diagnóstico.
- Published
- 2015
- Full Text
- View/download PDF
9. Resistencia química de concretos de activación alcalina ceniza volante/escoria: Sulfatos y ácidos.
- Author
-
Gustavo Valencia-Saavedra, William, Eugenia Angulo-Ramírez, Daniela, and Mejía de Gutiérrez, Ruby
- Abstract
One of the most important features of concrete, in addition to its mechanical properties, is its durability, which is associated to the in-service life of structures exposed to certain conditions or environments; this property is required to define the potential application fields and facilitate the commercialization of new cementing materials. In this study, the chemical resistance of a concrete based on a binary mixture of fly ash (FA) and blast furnace slag (GBFS) in an 80/20 ratio was evaluated. A concrete based on Portland cement (OPC) was used as a reference material. The compressive strength of Geo FA/GBFS at 28 days cured at room temperature was 42.9 MPa, 26% higher than that reported by the OPC concrete. Geo FA/GBFS exposed to sulfates does not show expansion, and the loss of compressive strength at 180 days aged of exposure was not significant (2%) compared to OPC concrete (39%). In the case of exposure to acids, FA/GBFS had a loss of resistance of 39% and OPC of up to 70%. These characteristics show the best performance of the activated material and its potential use in aggressive environments. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
10. EL PROBLEMA DE LAS CLASES NATURALES EN QUÍMICA: ALGUNAS DIFICULTADES PARA EL MICROESTRUCTURALISMO.
- Author
-
MARTÍNEZ GONZÁLEZ, JUAN CAMILO and CÓRDOBA, MARIANA
- Subjects
- *
PHILOSOPHY of science , *CHEMISTRY , *MICROSTRUCTURE , *ATOMIC number , *MOLECULAR shapes , *ACIDS - Abstract
Our purpose is to subvert the traditional analysis of the problem of natural kinds in philosophy of science, which will be analyzed from a synchronic perspective and focusing on chemistry. Three problems of essentialist microstructuralism in chemistry will be considered: (1) the atomic number is insufficient as an essential property and criterion, (2) quantum mechanics cannot account for molecular shape and, hence, for important macroscopic properties of substances, (3) it is not possible to define relevant properties, as acidity, from microscopic ones. We will argue it is convenient to maintain the notion of natural kind, though, but it can be redefined from the perspective of active realism and ideological pluralism proposed by Hasok Chang. This approach allows us to think that classifications must not be considered from an essentialist approach, but they are not arbitrary or merely conventional either, since reality can make a classification system fail and make another one work. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
11. Age estimation in humans through the analysis of aspartic acid racemization from teeth: a scoping review of methods, outcomes, and open research questions
- Author
-
Giovanna Teixeira Matteussi, Victor Jacometti, Ademir Franco, and Ricardo Henrique Alves da Silva
- Subjects
Adult ,Aspartic Acid ,Cross-Sectional Studies ,Dentin ,Forensic Anthropology ,Humans ,ÁCIDOS ,Age Determination by Teeth ,Tooth ,Law ,Forensic Dentistry ,Pathology and Forensic Medicine - Abstract
Teeth are considered the most resistant structures in the human body. In forensic odontology, teeth are useful for human identification, especially when dental age estimation is necessary. Despite numerous studies, there is no consensus regarding the best methods for dental age estimation. The analysis of aspartic acid racemization, however, has shown promising results. This scoping review aimed to present a descriptive synthesis of the current literature regarding dental age estimation through aspartic acid racemization. Four electronic databases were screened: PubMed, Scielo, Web of Science, and Scopus. Cross-sectional studies published before April 2021 were selected. From 206 articles found, 26 met the eligibility criteria. Several experimental protocols and laboratory settings were detected, but the different protocols did not seem to significantly reduce error rates in dental age estimation. The analysis of aspartic acid racemization in human dental tissues produced accurate and potentially reliable results for age estimation. Aspartic acid racemization stands out especially in the adulthood - age category in which other methods struggle to deliver proper performances. Studies with larger samples, independent testing, and standardized laboratory procedures are necessary. Equator-like reporting guidelines are encouraged to enable future systematic reviews and meta-analyses.
- Published
- 2022
12. Embriotoxicidade induzida pelo ácido perfluorooctanóico e cádmio em Gallus gallus
- Author
-
Kmecick, Melyssa, 1992, Grade, Carla Vermeulen Carvalho, 1983, Universidade Federal do Paraná. Setor de Ciências Biológicas. Programa de Pós-Graduação em Biologia Celular e Molecular, and Machado, Claudia Feijó Ortolani
- Subjects
Neurulação ,Cadmio ,Malformações (Anatomia) - Aspectos genéticos ,Metais pesados ,Histologia ,Mortalidade ,Ácidos ,Morfologia - Abstract
Orientadora: Profa. Dra. Claudia Feijó Ortolani-Machado Coorientadora: Profa. Dra. Carla Vermeulen Carvalho Grade Tese (doutorado) - Universidade Federal do Paraná, Setor de Ciências Biológicas, Programa de Pós-Graduação em Biologia Celular e Molecular. Defesa : Curitiba, 31/03/2022 Inclui referências Resumo: O ácido perfluorooctanóico (PFOA) e o cádmio (Cd) são poluentes persistentes no ambiente, bioacumuláveis e capazes de transpor a barreira placentária. A exposição a esses contaminantes no período pré-natal interfere no desenvolvimento, comprometendo o crescimento e induzindo malformações no sistema nervoso, como defeitos do tubo neural (TN). No ambiente os organismos vivos estão expostos a uma mistura complexa de poluentes que podem interagir, potencializando ou inibindo seus efeitos tóxicos. Por isso, o estudo da neurotoxicidade no desenvolvimento induzida pelo PFOA e Cd é altamente relevante. O objetivo desse trabalho foi avaliar os efeitos desses contaminantes, isoladamente e em mistura, em dose única in ovo, sobre diferentes parâmetros, em embriões de Gallus gallus. Para isso, foram realizadas análises de mortalidade, ocorrência de malformações e caracterização histológica, análise de rede e enriquecimento funcional a partir de genes selecionados em base de dados toxicogenômicos comparativos, além de avaliação anatômica de animais eclodidos. Inicialmente, foram avaliadas diferentes resinas de incorporação para o estudo histológico dos embriões, sendo a historesina a que proporcionou maior precisão de orientação dos embriões para corte, aliada à excelente preservação das estruturas e poucos artefatos. Posteriormente, a exposição dos embriões foi realizada injetando-se solução de contaminante ou veículo na câmara de ar, previamente à incubação. As concentrações utilizadas foram 0,5 ng.ml-1, 5 ng.ml-1 e 50 ng.ml-1 de PFOA, 0,05 Mi.ml-1, 0,5 ng.ml-1 e 5 Mig.ml- 1 de Cd e a mistura de PFOA à 5 ng.ml-1 e Cd à 0,5 Mi g.ml-1. Os embriões foram incubados por 2 a 6 dias, 8, 21 dias, até a eclosão ou no máximo 24 dias. Foram avaliadas a mortalidade embrionária, a ocorrência de malformações e as alterações histológicas envolvidas nas malformações causadas nos estádios HH14 e HH18, com foco no tubo neural. O material coletado foi processado em historesina, com coloração de hematoxilina e eosina e ácido periódico de Schiff (PAS). Alterações significativas no aumento da mortalidade e malformações indicaram o efeito embriotóxico dos contaminantes no embrião de galinha. As alterações teciduais encontradas no TN corroboram as alterações observadas em montagem total de embriões expostos ao PFOA e Cd nas mesmas concentrações, sendo elas: desorganização das vesículas encefálicas, TN aberto, presença de aglomerados celulares e/ou células apoptóticas na luz do tubo neural, células apoptóticas no neuroepitélio e alteração na forma do TN. A marcação com PAS evidenciou a membrana basal principalmente da notocorda e TN, sendo que a intensidade média de marcação nas secções foi reduzida significativamente em relação ao controle, principalmente no HH18. Esses resultados revelam a ação desses contaminantes a nível histológico, já em estágios iniciais e foram compilados em um índice de lesão elaborado para embriões de galinha em estágios iniciais de desenvolvimento. Além disso, apontam os possíveis mecanismos celulares da ocorrência das malformações, que foram corroborados pela análise de enriquecimento funcional. Nos indivíduos eclodidos e não eclodidos, foram observadas alterações anatômicas compatíveis com as malformações encontradas nos embriões em estágios mais iniciais, evidenciando a permanência dessas alterações ao longo do desenvolvimento. Abstract: Perfluorooctanoic acid (PFOA) and cadmium (Cd) are persistent and bioaccumulative environmental pollutants capable of crossing the placental barrier. Prenatal exposure to these contaminants interferes with development, impairing growth and inducing malformations in the nervous system, such as neural tube (NT) defects. Living organisms are exposed to complex mixtures of pollutants, which can interact, enhancing or inhibiting their toxic effects. Thus, the study of developmental neurotoxicity induced by PFOA and Cd, alone and in a mixture, is highly relevant. This work aimed to evaluate the effects of PFOA and Cd, isolated and in a mixture, in a single dose in ovo, on several parameters in the Gallus gallus embryo. To this end, mortality, malformations occurrence, histological characterization, network and functional enrichment of cured genes from Comparative Toxicogenomics Database (CTD), anatomical evaluation of hatched and non-hatched chicks were assessed. Initially, different embedding resins were evaluated for the histological study of the embryos, and historesin was the one that provided greater precision of orientation of the embryos for sectioning, allied to the excellent preservation of the structures and fewer artifacts. After, embryo exposure was performed by injecting contaminant solution or vehicle into the air chamber, before incubation. The concentrations used were 0.5 ng.ml-1, 5 ng.ml-1 and 50 ng.ml-1 of PFOA, 0.05 Mig.ml-1, 0.5 Mi.ml-1 and 5 ?g. ml-1 of Cd and the mixture of 5 ng.ml-1 PFOA and 0.5 Mi.ml-1 Cd. Embryos were incubated for 2 to 6 days, 8, 21, until hatching or a maximum of 24 days. Then, embryo mortality, the occurrence of malformations, and histological changes were characterized in stages HH14 and HH18, focusing on the neural tube. The collected material was processed in historesin and stained with hematoxylin and eosin (H&E) and periodic acid Schiff (PAS). Significant changes in mortality and occurrence of malformations indicated the teratogenic effect of contaminants on the chick embryo. Tissue changes found in NT corroborate alterations observed in the whole-mount analysis of embryos exposed to PFOA and Cd at the same concentrations, namely: brain vesicles disorganization, open NT, presence of cell clusters and/or apoptotic cells in the NT lumen, apoptotic cells in the neuroepithelium and alteration in the shape of the NT. PAS staining evidenced mainly the notochord and TN the basement membranes, and the average intensity of staining in the sections was significantly reduced when compared with the control, mainly at HH18. These results reveal the action of these contaminants at the histological level, even in early stages, and were compiled into a lesion index developed for chicken embryos at early stages of development. In addition, they point out the possible cellular mechanisms for the occurrence of malformations, which were corroborated by the analysis of functional enrichment. In hatched and non-hatched individuals, anatomical alterations compatible with the malformations found in early-stage embryos were observed, evidencing the permanence of these alterations throughout development.
- Published
- 2022
13. Las consecuencias del delito de lesiones con agentes químicos, ácido y/o sustancias similares y sus agravantes, vulneran el principio de proporcionalidad en Colombia
- Author
-
Rozo-Gaitán, Karen Alejandra and Uribe-Ruiz, Mauricio
- Subjects
PRINCIPIO DE PROPORCIONALIDAD DE LA SANCIÓN ,LESIÓN CON PRODUCTO QUÍMICO ,Vulneración ,Ácidos ,Principio de proporcionalidad ,Lesiones personales - Abstract
Artículo de investigación Esta propuesta de investigación parte de identificar cual es el mínimo y máximo de la pena imponible de las consecuencias jurídicas del tipo penal de lesiones con agentes químicos, ácido y/o sustancias similares y sus agravantes, con el fin de reconocer si la dosificación punitiva lesiona o no el principio de proporcionalidad. (Tomado de la fuente). Pregrado Abogado INTRODUCCIÓN 1. LA PROPORCIONALIDAD COMO PRINCIPIO DE LA SANCIÓN PENAL 2. ANÁLISIS NORMATIVO 3. CONCLUSIONES BIBLIOGRAFÍA
- Published
- 2022
14. Trauma químico del segmento anterior Chemical trauma of the anterior segment
- Author
-
Justo Luís Noriega Martínez and Roberto Alejandro Guerra García
- Subjects
ácidos ,álcalis ,trauma químico del segmento anterior ,acids ,alkalis ,anterior segment chemical injury ,Ophthalmology ,RE1-994 - Abstract
Se realizó una revisión de la situación actual y manejo de la urgencia de este tipo particular de trauma ocular. Se detectó el trauma químico por álcalis (58,5 %) como el agente etiológico más importante, además de ser el más peligroso entre las sustancias que pueden provocarlo. El lavado profuso con agua o soluciones balanceadas, continúa como el tratamiento de elección en el manejo inicial, y depende de este, la integridad de las estructuras oculares y la agudeza visual final que alcanzará el paciente. Se propone un flujograma con la conducta a seguir en estos casos de forma general.A review of the current situation and management of the ocular chemical injury in the emergency room was made. Alkalis was the most frequent and dangerous etiological agent (58,5 %) of chemical injuries in the eye. Ocular washing with abundant water or balanced solutions remains the treatment of choice as initial management, which determines the ocular structure integrity and the final visual acuity. A general flowchart containing the behavior to be adopted in these cases was submitted.
- Published
- 2012
15. Evaluación de la posible actividad rejuvenecedora del peeling con fenol en pieles maduras y sus retos cicatrizantes
- Author
-
Patrícia Tavares da Silva and Viviane Marinho dos Santos
- Subjects
Aging ,Envelhecimento ,Estética ,Acids ,Envejecimiento ,Aesthetics ,General Earth and Planetary Sciences ,Ácidos ,General Environmental Science - Abstract
A utilização de ácidos nos procedimentos estéticos vem se tornando cada vez mais recorrente e para comprovar sua eficácia, várias pesquisas foram realizadas nos últimos anos. Assim, o objetivo deste estudo foi realizar um levantamento bibliográfico no período de dez anos em bases de dados variadas, a fim de realizar uma busca mais diversa a respeito da utilização do peeling de fenol no processo de rejuvenescimento e seus desafios de cicatrização em peles maduras, evidenciando seus benefícios e eficácia. Após análise dos artigos, ficou evidente a eficiência e os benefícios que o peeling de fenol proporciona aos pacientes que buscam aumentar a autoestima e melhorar o aspecto da pele no quesito de machas e cicatrizes. Toda via, ressalta-se a importância de ter um profissional de qualidade e os cuidados necessários no pós-peeling. The use of acids in aesthetic procedures has become increasingly recurrent and to prove its effectiveness, several studies have been carried out in recent years. Thus, the objective of this study was to carry out a bibliographic survey over a period of ten years in various databases, in order to carry out a more diverse search regarding the use of phenol peeling in the rejuvenation process and its healing challenges in mature skins, highlighting its benefits and effectiveness. After analyzing the articles, it became evident the efficiency and benefits that phenol peeling provides to patients who seek to increase self-esteem and improve the appearance of the skin in terms of blemishes and scars. However, the importance of having a quality professional and the necessary post-peeling care is emphasized. El uso de ácidos en procedimientos estéticos se ha vuelto cada vez más recurrente y para comprobar su eficacia se han realizado varios estudios en los últimos años. Así, el objetivo de este estudio fue realizar un levantamiento bibliográfico durante un período de diez años en diversas bases de datos, con el fin de realizar una búsqueda más diversa respecto al uso del peeling con fenol en el proceso de rejuvenecimiento y sus desafíos curativos en pieles maduras, destacando sus beneficios y eficacia. Tras analizar los artículos, se hizo evidente la eficacia y los beneficios que brinda el peeling con fenol a los pacientes que buscan aumentar la autoestima y mejorar el aspecto de la piel en cuanto a manchas y cicatrices. Sin embargo, se destaca la importancia de contar con un profesional de calidad y los necesarios cuidados post-peeling.
- Published
- 2022
16. Abordagem analítica de ácidos graxos em dietas enterais: uma comparação entre rótulos e resultados analíticos.
- Author
-
Luiza Führ, Aline, Scaramal Madrona, Grasiele, Theodoro Toci, Aline, de Carvalho Lourenço, Emilene, Barboza Valdez, Aldo Sindulfo, and Boroski, Marcela
- Abstract
Copyright of Revista da Associação Brasileira de Nutrição is the property of Associacao Brasileira de Nutricao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2022
17. Terapia nutricional en pacientes adultos con quemaduras del tracto gastrointestinal por cáusticos Nutrition therapy for adult patients with caustic injuries to gastrointestinal tract
- Author
-
N. A. Muñoz Botero, A. M.ª Pérez Cano, R. Rodríguez Herrera, M. P. Rojas Gómez, and F. A. Soler Páez
- Subjects
Cáusticos ,Ácidos ,Álcalis ,Ingesta ,Terapia Nutricional ,Caustic ,Acids ,Alkalis ,Ingestion ,Treatment ,Nutrition therapy ,Nutritional diseases. Deficiency diseases ,RC620-627 - Abstract
Objetivos: Presentar la experiencia del Grupo de Terapia Nutricional del Hospital El Tunal, en el manejo nutricional de pacientes adultos con quemaduras por cáusticos del tracto gastrointestinal. Materiales y métodos: Es un estudio retrospectivo, descriptivo de pacientes manejados por el Grupo de Terapia Nutricional por quemaduras por cáusticos del tracto gastrointestinal en un periodo comprendido entre Enero de 2000 y Diciembre de 2007. Se revisaron las historias clínicas de los pacientes que tenían diagnóstico de quemaduras por cáusticos. Se analizaron los datos pertinentes al manejo nutricional, la evolución y el resultado final dedichos pacientes. Resultados: Se atendieron 30 pacientes, 17 hombres y 13 mujeres con edad promedio 34,4 ± 17,2 años. La ingesta del cáustico fue por intento de suicidio en 22 (73,3%) pacientes y accidental en 8 (26,7%). La mortalidad global fue alta (43,3%). El 46,9% de los pacientes mostró perdida de peso y balance nitrogenado negativo el 62,5%. Diez y siete pacientes (53,12%) recibieron nutrición mixta (enteral y/o parenteral) por un tiempo promedio de 24 ± 22 días. Al comparar dos grupos clasificados como quemadura del TGI Grave vs Moderada se encontró que fue significativamente diferente la mortalidad, la estancia hospitalaria y el valor final de albúmina. Conclusiones: La quemadura del tracto gastrointestinal por cáusticos es una entidad poco frecuente, sucede principalmente en jóvenes por intento de suicidio y se asocia a alta mortalidad, sobre todo en quemaduras graves. Esta agresión lleva a catabolismo importante que produce balance nitrogenado negativo y perdida de peso. Estos pacientes requieren intervención nutricional temprana que puede extenderse por varios meses.Objectives: To present here the experience of our Nutrition Therapy Team of the Hospital El Tunal, for the nutritional management of adult patients with caustic injuries to gastrointestinal tract. Materials and methods: This is a retrospective, descriptive study of patients with caustic injuries to gastrointestinal tract managed by our Nutrition Therapy Team between January 2000 and December 2007. We revisited the clinical history of patients with diagnosis of caustic injury. Various nutritional variables, as well as the evolution and outcome were pooled and analyzed. Results: A total of 30 patients, 17 male y 13 female with a mean age of 34.4 ± 17.2 years old were found. The ingestion of caustics was suicidal intent in 22 (73.3%) and accidental in 8 (26.7%). The global mortality was high (43.3%). Weight loss was found in 46.9% of the patients and a negative nitrogen balance in 62.5%. Sixteen patients (53.12%) were managed with mixed nutrition (enteral and/or parenteral) for a mean time of 24 ± 22 days. We compared two groups Moderate vs Severe, according to the severity of the caustic injury to gastrointestinal tract and found that mortality, the length of hospital stay and the final albumin value were significantly different among groups. Conclusions: Caustic injuries to gastrointestinal tract are not frequent, they are found mainly in young patients with suicidal intent and are associated with high mortality, especially in severe injuries. This aggression causes important catabolic state leading to a negative nitrogen balance and weight loss. These patients require early nutritional intervention sometimes extended for months.
- Published
- 2010
18. Aislamiento de los ácidos ent-16-kauren-19-oico y 18-angeloiloxi-ent-16- kauren-19-0ic0 de las raíces de smallanthus riparlus.
- Author
-
Jairo Calle, Augusto Rivera, José Herrera, Javier Gutiérrez, and P. JOSEPH NATHAN
- Subjects
Ácidos ,Raices de Smallanthus riparius ,Métodos espectroscópicos ,Chemistry ,QD1-999 - Abstract
Del extracto de éter de petróleo (pe. 40-60°) de las raices de Smallanthus riparius se aislaron ácido ent-16-Kauren-19-oico (I) y ácido 18-angeloiloxi-ent-16-Kauren-19-oico (II) con buenos rendimientos. Las estructuras se confirmaron por métodos espectroscópicos. Se asignaron inequívocamente las señales del grupo angelato en el espectro de RMN13C) del compuesto (II) usando técnicas bidímensionales de correlación heteronuclear 1H-13D.
- Published
- 2010
19. Influencia de un régimen de bajos insumos en el cultivo de 25 variedades de tomate para el contenido de ácidos orgánicos y azúcares
- Author
-
Castillo Giménez, Andrea
- Subjects
Bajos insumos ,Low inputs ,Mejora vegetal ,Sostenibilidad ,Tomato ,GENETICA ,Sustainability ,Tomate ,Plant improvement ,Ácidos ,Azúcares ,Sugars ,Acids ,Grado en Ciencia y Tecnología de los Alimentos-Grau en Ciència i Tecnologia dels Aliments - Abstract
[ES] El tomate es considerado una de las hortalizas más consumidas en todo el mundo y con un alto valor económico. Su demanda ha ido aumentando con el paso del tiempo y con ella su cultivo y posterior comercio. Una parte de la producción se destina al consumo en fresco, desempeñando una importante función en la dieta alimentaria al ser una de las fuentes de vitamina C, vitamina E y carotenoides más importantes. En el sector de la agricultura, el cultivo del tomate además tiene una gran repercusión directa en el mantenimiento del medio rural y el medio ambiente, donde además se pretende fomentar una agricultura competitiva, pero a la vez sostenible, de bajos insumos, obteniendo más con menos. Con el paso de las décadas, diferentes programas de mejora genética del tomate han sido sucediéndose, siendo algunos de ellos: mayor resistencia a plagas, mayor producción o mayor vida postcosecha del producto debido a la comercialización global de éste. Todos estos objetivos dejaban de lado la calidad organoléptica del producto, relacionada directamente con la cantidad de azúcares y ácidos presentes, que se vuelve a demandar actualmente en el mercado. Debido a ello, existen proyectos como el proyecto BRESOV, a nivel Europeo, que se han concebido con la intención de encontrar cultivos que se adapten a condiciones climatológicas nuevas en cortos plazos de tiempo (como problemas de sequía, poca fertilización, salinidad, altas temperaturas),para luchar frente nuevas plagas y enfermedades y además, tener en cuenta la reciente demanda de los consumidores, por productos con más sabor y ecológicos, con lo que los programas de mejora vegetal a nivel mundial han tenido que reinventarse. El objetivo principal del presente trabajo de investigación se centra en la evaluación de la calidad organoléptica de 25 variedades de tomate estudiando su contenido en azúcares reductores (glucosa y fructosa) y los principales ácidos orgánicos presentes en el fruto (ácido málico y cítrico). También se evaluó la influencia del ambiente (las variedades ensayadas fueron cultivadas en Valencia, España y Nápoles, Italia) y la influencia de la escasez de nitrógeno y riego sobre los componentes estudiados. Los resultados obtenidos muestran una gran variabilidad en el contenido de azúcares (glucosa y fructosa) y ácidos orgánicos (cítrico y málico) para las variedades estudiadas en este ensayo, distinguiendo perfectamente los perfiles más ácidos de los más dulces. Además, mostraron una clara influencia del ambiente en el que fueron cultivadas, dando perfiles significativamente más dulces en las variedades cultivadas en Italia. También se pudo observar cómo las concentraciones de azúcares y ácidos aumentan en condiciones de sequía, y se mantienen sin cambios significativos en las condiciones de menor fertilización y estándar., [EN] Tomato is considered one of the most consumed vegetables in the world and with a high economic value. Human consumption has been increasing over time and therefore its cultivation and trade. A part of the production is intended for fresh consumption, playing an important role in the human diet as it is one of the most important sources of vitamin C, vitamin E and carotenoids. In the agriculture sector, tomato cultivation also has a great direct impact on the maintenance of the rural environment, where it is also intended to promote competitive agriculture, but at the same time sustainable, with low inputs. Over the decades, different tomato genetic improvement programs have been taking place, some of them being: greater resistance to pests, greater production or longer post-harvest life of the product due to its global commercialization. All these objectives did not focus the organoleptic quality of the product, directly related to the amount of sugars and acids present, which is currently important on the market. As a result, there are projects such as the BRESOV project, at the European level, which have been conceived with the intention of finding crops that adapt to new weather conditions in short periods of time (such as problems of drought, low fertilization, salinity, high temperatures), to fight against new pests and diseases and also take into account the recent consumer demand for more flavorful and ecological products, with which plant improvement programs worldwide have had to reinvent themselves. The main objective of this research work is focused on the evaluation of the organoleptic quality of 25 tomato varieties studying their content in reducing sugars (glucose and fructose) and the main organic acids present in the fruit (malic and citric acid). The influence of the environment was also evaluated (the tested varieties were cultivated in Valencia, Spain and Naples, Italy) and the influence of nitrogen shortage and irrigation on the studied components. The results obtained show a great variability in the content of sugars (glucose and fructose) and organic acids (citric and malic) for the varieties studied in this test, perfectly distinguishing the most acidic profiles from the sweetest ones. In addition, they showed a clear influence of the environment in which they were grown, giving significantly sweeter profiles in the varieties grown in Italy. It was also possible to observe how the concentrations of sugars and acids increase in drought conditions, and remain without significant changes in the conditions of lower fertilization and standard.
- Published
- 2021
20. The impact of the use of experimentation and digital technologies of information and communication in the formation of acid and base concepts for elementary school students
- Author
-
Broietti, Elisama Rodrigues Bazilio, Lambach, Marcelo, Pauletti, Fabiana, Pricinotto, Gustavo, and Ribeiro, Marcus Eduardo Maciel
- Subjects
Teaching - Investigation ,Ensino ,CIENCIAS HUMANAS::EDUCACAO::ENSINO-APRENDIZAGEM [CNPQ] ,Ensino - Investigação ,Ácidos ,Science - Study and teaching ,Bases (Química) ,Ciência - Estudo e ensino ,Química - Experiências ,Acids ,Chemistry - Experiments ,Bases (Chemistry) - Abstract
Acompanha: Ensino por investigação para o ensino fundamental Esta pesquisa apresenta uma proposta de Sequência de Ensino por Investigação (SEI) sobre a formação de conceitos de ácidos e bases a partir da experimentação e do uso das Tecnologias Digitais de Informação e Comunicação (TDIC) no Ensino de Ciências (EC) para estudantes do Ensino Fundamental. Tem como problema e guia de pesquisa a questão: De que modo o uso da experimentação e das TDIC podem contribuir para a formação do conceito de ácidos e bases para estudantes do Ensino Fundamental? Como objetivo desta questão pretendeu-se construir e analisar uma Sequência de Ensino por Investigação (SEI) sobre a formação dos conceitos de ácidos e bases para estudantes do Ensino Fundamental com o uso da experimentação e das TDIC. A SEI desenvolvida nesta pesquisa se baseou no uso do laboratório aberto e de recursos tecnológicos. Com o envolvimento de 16 estudantes do 9º ano do Ensino Fundamental, a pesquisa foi desenvolvida em uma escola da rede pública estadual, no município de Curitiba, estado do Paraná. Esta pesquisa de cunho qualitativo caracteriza-se por ser interventiva. O corpus da pesquisa se constituiu da gravação e transcrição dos discursos dos estudantes, fotos e registro de um diário de campo, questionário, roda de conversa, atividade experimental e uso de um simulador. Para análise dos dados produzidos utilizou-se a Análise Textual Discursiva (ATD), que possibilita ao pesquisador realizar interpretações de suas perspectivas e supor possíveis resultados. Da análise das respostas propostas para os estudantes emergiram cinco categorias: 1) Ensino de Ciências e investigações científicas, 2) processo de formação dos conceitos de ácidos e bases, 3) controle de biossegurança, 4) levantamento de hipóteses, 5) engajamento dos estudantes, demonstrando que uma pesquisa se faz com investigação, levantamento de hipóteses, discussões, análise de dados e experimentos. Os objetivos foram atingidos, desde a aplicação da SEI, seguindo os preceitos do Ensino por Investigação, até os levantamentos bibliográficos que trouxeram para a pesquisa a análise dos livros didáticos direcionados para o Ensino de Ciências e os encaminhamentos de TDIC e atividades experimentais, assim como as possibilidades de aplicação do Ensino por Investigação. Após a aplicação e o apontamento de resultados e discussões em relação à SEI, foi elaborado como Produto Educacional um material de apoio docente com encaminhamentos metodológicos para o ensino de ácidos e bases no Ensino Fundamental. This research presents a proposal of the Sequences of Teaching by Investigation (SEI) about the formation of concepts of acids and bases from experimentation and use of Digital Technologies of Information and Communication (TDIC) in Science Teaching (EC) for Elementary School students. It has as a problem and research guide the following question: How the use of experimentation and TDIC can contribute to the concept formation of acids and bases to Elementary School students? This research aims to build and analyze a Sequence of Teaching by Investigation (SEI) about the concepts formation of acids and bases to Elementary School students using the experimentation and TDIC. The SEI, developed in this research, was based on the use of open laboratory and technological resources. With the involvement of 16 students from 9th grade of Elementary School, this work was carried out in a state public school, in the city of Curitiba, Paraná. This qualitative research is characterized by being interventional. The corpus of research consists of recording and transcription of students’ speeches, photos and field diary registration, questionnaire, roundtable, experimental activities and using a simulator. To analyze data, it was used the Discursive Text Analysis (ATD), which allows the researcher to interpret their perspectives and assume possible results. From the analysis of the answers proposed to the students, five categories emerged: 1) Science teaching and scientific investigations, 2) process of formation of the acids and bases concepts, 3) biosafety control, 4) raising of hypotheses, 5) students’ engagement, showing that research is done with investigation, hypotheses raised, discussions, data analysis and experiments. The goals were achieved, from the application of SEI, following the precepts of Teaching by Investigation, to bibliographic surveys that brought to the research the analysis of schoolbooks directed to the Science Teaching and the referrals of TDIC and experimental activities, as well as the possibilities of applying the Teaching by Investigation. After applying and pointing the results and discussions related to Sequences of Teaching by Investigation, it was developed as Education Product, a teaching support material with methodological guidelines to the teaching of acids and bases in Elementary School.
- Published
- 2021
21. Transformação de carbociclo em carboidrato
- Author
-
Cerchiaro, Giselle, Baptistella, Lucia Helena Brito, 1955, Universidade Estadual de Campinas. Instituto de Química, and UNIVERSIDADE ESTADUAL DE CAMPINAS
- Subjects
Síntese orgânica ,Ácidos - Abstract
Orientador : Lucia Helena Brito Baptistella Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica Mestrado
- Published
- 2021
22. 'Oxidação do cicloexeno a cicloexanona pelo Processo Wacker'
- Author
-
Melgo, Marisa Simone, Schuchardt, Ulf Friedrich, 1946-2020, Lago, Rochel Montero, Dias, Gilson Herbert Magalhães, Universidade Estadual de Campinas. Instituto de Química, and UNIVERSIDADE ESTADUAL DE CAMPINAS
- Subjects
Catálise ,Ácidos ,Paládio - Abstract
Orientador: Ulf Schuchardt Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica Mestrado Química Inorgânica Mestre em Química
- Published
- 2021
23. Influencia de un régimen de bajos insumos en el cultivo de 25 variedades de tomate para el contenido de ácidos orgánicos y azúcares
- Author
-
Plazas Ávila, María de la O, Adalid Martínez, Ana Maria, Universitat Politècnica de València. Departamento de Biotecnología - Departament de Biotecnologia, Universitat Politècnica de València. Escuela Técnica Superior de Ingeniería Agronómica y del Medio Natural - Escola Tècnica Superior d'Enginyeria Agronòmica i del Medi Natural, Castillo Giménez, Andrea, Plazas Ávila, María de la O, Adalid Martínez, Ana Maria, Universitat Politècnica de València. Departamento de Biotecnología - Departament de Biotecnologia, Universitat Politècnica de València. Escuela Técnica Superior de Ingeniería Agronómica y del Medio Natural - Escola Tècnica Superior d'Enginyeria Agronòmica i del Medi Natural, and Castillo Giménez, Andrea
- Abstract
[ES] El tomate es considerado una de las hortalizas más consumidas en todo el mundo y con un alto valor económico. Su demanda ha ido aumentando con el paso del tiempo y con ella su cultivo y posterior comercio. Una parte de la producción se destina al consumo en fresco, desempeñando una importante función en la dieta alimentaria al ser una de las fuentes de vitamina C, vitamina E y carotenoides más importantes. En el sector de la agricultura, el cultivo del tomate además tiene una gran repercusión directa en el mantenimiento del medio rural y el medio ambiente, donde además se pretende fomentar una agricultura competitiva, pero a la vez sostenible, de bajos insumos, obteniendo más con menos. Con el paso de las décadas, diferentes programas de mejora genética del tomate han sido sucediéndose, siendo algunos de ellos: mayor resistencia a plagas, mayor producción o mayor vida postcosecha del producto debido a la comercialización global de éste. Todos estos objetivos dejaban de lado la calidad organoléptica del producto, relacionada directamente con la cantidad de azúcares y ácidos presentes, que se vuelve a demandar actualmente en el mercado. Debido a ello, existen proyectos como el proyecto BRESOV, a nivel Europeo, que se han concebido con la intención de encontrar cultivos que se adapten a condiciones climatológicas nuevas en cortos plazos de tiempo (como problemas de sequía, poca fertilización, salinidad, altas temperaturas),para luchar frente nuevas plagas y enfermedades y además, tener en cuenta la reciente demanda de los consumidores, por productos con más sabor y ecológicos, con lo que los programas de mejora vegetal a nivel mundial han tenido que reinventarse. El objetivo principal del presente trabajo de investigación se centra en la evaluación de la calidad organoléptica de 25 variedades de tomate estudiando su contenido en azúcares reductores (glucosa y fructosa) y los principales ácidos orgánicos presentes en el fruto (ácido málico y cítrico). También se ev, [EN] Tomato is considered one of the most consumed vegetables in the world and with a high economic value. Human consumption has been increasing over time and therefore its cultivation and trade. A part of the production is intended for fresh consumption, playing an important role in the human diet as it is one of the most important sources of vitamin C, vitamin E and carotenoids. In the agriculture sector, tomato cultivation also has a great direct impact on the maintenance of the rural environment, where it is also intended to promote competitive agriculture, but at the same time sustainable, with low inputs. Over the decades, different tomato genetic improvement programs have been taking place, some of them being: greater resistance to pests, greater production or longer post-harvest life of the product due to its global commercialization. All these objectives did not focus the organoleptic quality of the product, directly related to the amount of sugars and acids present, which is currently important on the market. As a result, there are projects such as the BRESOV project, at the European level, which have been conceived with the intention of finding crops that adapt to new weather conditions in short periods of time (such as problems of drought, low fertilization, salinity, high temperatures), to fight against new pests and diseases and also take into account the recent consumer demand for more flavorful and ecological products, with which plant improvement programs worldwide have had to reinvent themselves. The main objective of this research work is focused on the evaluation of the organoleptic quality of 25 tomato varieties studying their content in reducing sugars (glucose and fructose) and the main organic acids present in the fruit (malic and citric acid). The influence of the environment was also evaluated (the tested varieties were cultivated in Valencia, Spain and Naples, Italy) and the influence of nitrogen shortage and irrigation on the studied comp
- Published
- 2021
24. Scientific bases for production of hard-cooked eggs preserved in brine
- Author
-
Antunes, Sofia Francisco, Coimbra, Manuel António, and Marinha, Mariana
- Subjects
Salmoura ,pH ,Condutividade ,Proteínas ,Ovo cozido ,Ácidos - Abstract
No presente trabalho estudou-se, ao longo de 7 experiências, a influência do sal e dos ácidos nas características físico-químicas e microbiológicas do ovo cozido conservado em salmoura, em ambiente industrial. Nas experiências 1 a 3 foi avaliado o impacto da diminuição de sal e ácidos da salmoura nas características do ovo cozido, na experiência 4 foi avaliada a evolução do pH e condutividade de soluções contendo diferentes concentrações de sal na presença de ovo cozido, na experiência 5 foi avaliado o impacto da temperatura de arrefecimento do ovo e temperatura da salmoura nas características físico-químicas da salmoura na presença de ovo cozido e nas experiências 6 e 7 foi avaliado o impacto de utilização de pré-salmouras nas características do ovo cozido. O aumento do pH das salmouras quando em contacto com os ovos é explicado pela migração de proteína, bicarbonato e água, contribuindo para a perda de massa do ovo. Este aumento pode levar à contaminação microbiológica, razão pela qual as salmouras devem ser suficientemente ácidas para neutralizar a migração dos compostos do ovo. Um dos ácidos utilizados é um ingrediente relevante para esta proteção. A diminuição da condutividade das salmouras deve-se à entrada de sal e de ácidos no ovo, assim como à saída de água, que vão contribuir para o seu sabor salgado e ácido. Neste trabalho é proposto que os ovos sejam submetidos a uma pré-salmoura antes da sua conservação numa salmoura contendo menos ácido e menos sal, permitindo obter ovos que, apesar de organoleticamente poderem possuir uma rigidez ligeiramente maior do que os ovos comerciais, possuam menor acidez e perceção de salgado, aproximando-os dos ovos acabados de cozer sem qualquer conservação. Num contexto de economia circular, a présalmoura que será descartada, por ter uma elevada concentração de proteína, o que lhe confere características de espumabilidade, poderá ser utilizada como ingrediente alimentar para outras aplicações. The present work studies, in 7 experiments, the influence of salt and acid on the physicochemical and microbiological characteristics of hardcooked eggs at an industrial environment. Experiments 1 to 3 evaluated the impact on characteristics of hard-cooked eggs of the decrease of salt and acids in brine; experiment 4 evaluated the pH and conductivity evolution a long time of solutions with different concentrations of salt in present of hard-cooked eggs; experiment 5 evaluated the impact of cooling temperature of egg and temperature of brine in physicochemical characteristics of brine in presence of hard-cooked eggs; and in experiments 6 and 7 it was evaluated the impact of using brine as a washing solution (pre-brine) in the characteristics of hard-cooked eggs. The brine pH increase when in contact with the hard-cooked eggs is explained by the migration of protein, bicarbonate, and water from the egg, contributing to a egg mass loss. This increase can result in a microbiological contamination, the reason why the brines should be acid enough to neutralize the compounds that migrate from the egg. One of the acids used is a relevant ingredient for this protection. The decrease of brine conductivity is due to and the salt and acid entrance in the egg and the running out of water, contributing to the egg salty and acid taste. In this work it is proposed to submit the eggs to a pre-brine solution prior to their conservation in a less acid and salty brine. This allows to obtain eggs that despite their slight toughness can be recognised organoleptically to be less acid and salty, approaching the characteristics of eggs ready cooked without any preservative. Under a circular economy context, the pre-brine that will be discarded, having a high concentration of proteins, with a foamability characteristics, can be used as a food ingredient for different applications. Mestrado em Bioquímica
- Published
- 2021
25. Investigating how biomass hydrolysis derivatives inhibit H2 production by an isolated Clostridium beijerinckii
- Author
-
Lucas Diniz Giraldeli, Bruna Constante Fonseca, and Valeria Reginatto
- Subjects
Ethanol ,biology ,Renewable Energy, Sustainability and the Environment ,Formic acid ,Metabolite ,Energy Engineering and Power Technology ,ÁCIDOS ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,biology.organism_classification ,01 natural sciences ,0104 chemical sciences ,Butyric acid ,chemistry.chemical_compound ,Hydrolysis ,Fuel Technology ,Clostridium beijerinckii ,chemistry ,Levulinic acid ,Fermentation ,Food science ,0210 nano-technology - Abstract
This study evaluates how fermentation inhibitors derived from biomass, namely 5-hydroxymethylfurfural (HMF), levulinic acid (LA), and formic acid (FA), affect H2 production by a Clostridium beijerinckii strain. The specific fermentative H2 production rate (μH2), bacterial cell growth rate (μ), and substrate (glucose) consumption rate (μS) during fermentation helped to estimate which HMF, LA, and FA concentrations inhibited 50% of the rates (IC50). IC50 for μ was 2.4, 2.7, and 1.4 g/L for HMF, LA, and FA, respectively. HMF inhibited H2 production the most potently and favored the lactate and ethanol pathways. Butyric acid was the only metabolite to be detected in the presence of LA or FA, which attested that these inhibitors completely inhibited the acetate pathway. The glucose consumption rate was the least affected by the inhibitors, and FA was more potent than HMF and LA. This information should be useful for more appropriate biomass feedstock application in fermentative H2 production.
- Published
- 2019
26. Highly Magnetizable Crosslinked Chloromethylated Polystyrene-Based Nanocomposite Beads for Selective Molecular Separation of 4-Aminobenzoic Acid
- Author
-
Paolin Rocio Cáceres-Vélez, Juliano A. Chaker, Anderson M. M. S. Medeiros, Abraham Francisco Palomec-Garfias, Katiúscia Vieira Jardim, Marcelo Henrique Sousa, Fábio Teles Costa, and Sergio Moya
- Subjects
Thermogravimetric analysis ,Materials science ,Nanocomposite ,General Chemical Engineering ,Ethylene glycol dimethacrylate ,Nanopartículas ,technology, industry, and agriculture ,Maghemite ,Nanoparticle ,macromolecular substances ,General Chemistry ,engineering.material ,Article ,lcsh:Chemistry ,chemistry.chemical_compound ,lcsh:QD1-999 ,chemistry ,Chemical engineering ,engineering ,Copolymer ,Ácidos ,Ácido benzóico ,Suspension polymerization ,Polystyrene - Abstract
In this work, we describe the preparation and characterization of highly magnetizable chloromethylated polystyrene-based nanocomposite beads. For synthesis optimization, acid-resistant core–shelled maghemite (γ-Fe2O3) nanoparticles are coated with sodium oleate and directly incorporated into the organic medium during a suspension polymerization process. A crosslinking agent, ethylene glycol dimethacrylate, is used for copolymerization with 4-vinylbenzyl chloride to increase the resistance of the microbeads against leaching. X-ray diffraction, inductively coupled plasma atomic emission spectroscopy, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy, and optical microscopy are used for bead characterization. The beads form a magnetic composite consisting of ∼500 nm-sized crosslinked polymeric microspheres, embedding ∼8 nm γ-Fe2O3 nanoparticles. This nanocomposite shows large room temperature magnetization (∼24 emu/g) due to the high content of maghemite (∼45 wt %) and resistance against leaching even in acidic media. Moreover, the presence of superficial chloromethyl groups is probed by Fourier transform infrared and X-ray photoelectron spectroscopy. The nanocomposite beads displaying chloromethyl groups can be used to selectively remove aminated compounds that are adsorbed on the beads, as is shown here for the molecular separation of 4-aminobenzoic acid from a mixture with benzoic acid. The high magnetization of the composite beads makes them suitable for in situ molecular separations in environmental and biological applications.
- Published
- 2019
27. Aminocyclopyrachlor and mesotrione sorption–desorption in municipal sewage sludge-amended soil
- Author
-
Miriam Hiroko Inoue, Marcelo Gomes de Oliveira, Tatiane Beatriz Mertens, Felipe Gimenes Alonso, Kassio Ferreira Mendes, and Valdemar Luiz Tornisielo
- Subjects
weak acid ,Materials Science (miscellaneous) ,Sorption ,ÁCIDOS ,Weed control ,lcsh:S1-972 ,Mesotrione ,leaching potential ,chemistry.chemical_compound ,Nutrient ,organic amendments ,chemistry ,Desorption ,Environmental chemistry ,tropical soil ,Freundlich equation ,Aminocyclopyrachlor ,lcsh:Agriculture (General) ,General Agricultural and Biological Sciences ,Sludge - Abstract
The application of sewage sludge (SS) in agriculture is a practice used worldwide, and it is commonly applied in sugarcane to supply nutrients, with beneficial effects on crop productivity and soil; but SS can increase sorption and decrease desorption of herbicides. However, in tropical soils such as in Brazil, there are no studies regarding the behavior of pre-emergent herbicides, mainly aminocyclopyrachlor and mesotrione, in SS-amended soil. The aim of the present study was to determine the effect of municipal SS applied in agriculture on the sorption–desorption of aminocyclopyrachlor and mesotrione in clay soil. Aminocyclopyrachlor (pyrimidine-2-14C-aminocyclopyrachlor) and mesotrione (cyclohexane-2-14C-mesotrione) sorption–desorption was evaluated using a batch equilibrium method. Soil was amended at 0% (control – unamended), 0.1%, 1%, and 10% (w∙w–1) of air-dried SS corresponding to 1.2, 12, and 120 t∙ha–1. The Freundlich Kf sorption values of aminocyclopyrachlor and mesotrione were similar for all treatments, ranging from 1.07 to 1.45 and 3.48 to 4.25 µmol (1–1/n) L1/n∙kg–1, respectively. Overall, the lowest Kd sorption value of these herbicides was reported for SS-amended soil (1%), while in the SS-amended soil (10%) it was higher than unamended soil. The H value for aminocyclopyrachlor was ~1 (no hysteresis) and for mesotrione was on average 0.4 (hysteresis occurring). In conclusion, the present study indicates that SS applied in any crop to supply nutrients can slightly affect the sorption–desorption of aminocyclopyrachlor and mesotrione, but this small difference does not affect the bioavailability of these herbicides for weed control.
- Published
- 2019
28. DESARROLLO DE BIODIESEL A PARTIR DE MATERIAS PRIMAS CON UN ALTO CONTENIDO DE ÁCIDOS GRASOS LIBRES
- Author
-
Sancho Fernández, María Pino, Universitat Politècnica de València. Departamento de Ingeniería Química y Nuclear - Departament d'Enginyeria Química i Nuclear, Universitat Politècnica de València. Escuela Técnica Superior de Ingenieros Industriales - Escola Tècnica Superior d'Enginyers Industrials, Monserrat Aguilar, Carlos, Sancho Fernández, María Pino, Universitat Politècnica de València. Departamento de Ingeniería Química y Nuclear - Departament d'Enginyeria Química i Nuclear, Universitat Politècnica de València. Escuela Técnica Superior de Ingenieros Industriales - Escola Tècnica Superior d'Enginyers Industrials, and Monserrat Aguilar, Carlos
- Abstract
[ES] Análisis de biodiesel obtenido mediante transesterificación de materias primas grasas con un contenido alto de ácidos grasos libres en su interior. Comparación de sus propiedades en función del catalizador utilizado(catalizador básico, sin catalizador y con distintos catalizadores ácidos) para su producción y el método de purificación para obtener el producto final., [EN] Analysis of biodiesel obtained by transesterification of fatty raw materials with a high content of free fatty acids inside. Comparison of its properties depending on the catalyst used (basic catalyst, without catalyst and with different acid catalysts) for its production and the purification method to obtain the final product.
- Published
- 2020
29. Efeito do ácido deoxicólico nas regiões submentoniana, inguinal e subplantar de ratos: análise clínica e histológica
- Author
-
Salum, Fernanda Gonçalves and Salum, Fernanda Gonçalves
- Published
- 2020
30. Study of the effect of dicumyl peroxide on morphological and physical properties of foam injection molded poly (lactic acid) / poly (butylene succinate) blends
- Author
-
López, Iván Darío, Campuzano Vallejo, Juan Fernando, López, Iván Darío, and Campuzano Vallejo, Juan Fernando
- Published
- 2020
31. Probing the charge transfer in a frustrated lewis pair by resonance raman spectroscopy and DFT calculations
- Author
-
Leandro Ramos Marques and Rômulo A. Ando
- Subjects
Steric effects ,Materials science ,Resonance Raman spectroscopy ,02 engineering and technology ,ÁCIDOS ,Borane ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Resonance (chemistry) ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Frustrated Lewis pair ,0104 chemical sciences ,Adduct ,Crystallography ,chemistry.chemical_compound ,chemistry ,Density functional theory ,Lewis acids and bases ,Physical and Theoretical Chemistry ,0210 nano-technology - Abstract
A classical Lewis adduct derives from a covalent bond between a Lewis acid and a base. When the adduct formation is precluded by means of steric hindrance the association of the respective acid-base molecular system is defined as a frustrated Lewis pair (FLP). In this work, the archetypal FLP Mes3 P/B(C6 F5 )3 was characterized for the first time by resonance Raman spectroscopy, and the results were supported by density functional theory (DFT) calculations. The charge transfer nature of the lowest energy electronic transition, from phosphine to borane, was confirmed by the selective enhancement of the Raman bands associated to the FLP chromophore at resonance condition. Herein, we demonstrate the use of resonance Raman spectroscopy as a distinguished technique to probe the weak interaction involved in FLP chemistry.
- Published
- 2021
32. Recuperación de ácidos y metales en baños agotados del decapado de aceros inoxidables
- Author
-
C. Frías and O. Pérez
- Subjects
decapado ,acero inoxidable ,ácidos ,recuperación ,metales ,Mining engineering. Metallurgy ,TN1-997 - Abstract
En la operación del decapado de los aceros inoxidables se producen anualmente en Europa unos 300.000 m3/año de efluentes de baños agotados. El tratamiento normal de estos efluentes mediante neutralización y depósito de los lodos generados presenta graves inconvenientes que requieren ser subsanados, para lo cual se ha comenzado a desarrollar un nuevo proceso denominado proceso PIBARE, que presenta una gran potencialidad comercial basado en el análisis técnico-económico preliminar para una planta de 10.000 m3/año, donde se obtiene un "pay back period" de unos dos años, con otras ventajas medioambientales, ya que se reciclarían los ácidos libres y complejos y se recuperarían los metales como subproductos comerciales o aleaciones reciclables. Se presenta una visión general del proyecto PIBARE y los resultados obtenidos en la etapa de laboratorio que se desarrolla actualmente.
- Published
- 1998
- Full Text
- View/download PDF
33. Aspergillus sclerotiorum: riesgo para la herencia cultural y la salud.
- Author
-
Carrazana-García, Daymí-I, González-Álvarez, Dayana, Díaz-Álvarez, Edgardo, Mesa-Garriga, Leyanis, Banguela-Castillo, Alexander, Chea-González, Annarella, and Cupull-Santana, Rene
- Abstract
Copyright of Universitas Scientiarum is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2014
- Full Text
- View/download PDF
34. Lesiones personales causadas con ácidos, álcalis, sustancias similares o corrosivas, una reforma del 2013.
- Author
-
Díaz Granados, Carlos Gónima
- Subjects
- *
ACCIDENT law , *WORK-related injury laws , *INDUSTRIAL safety laws , *LAW , *LAW reform , *HUMAN abnormality laws , *WOUNDS & injuries - Abstract
This work is a study on the causes that justified the creation of the new offense of ausing personal injury deformity by the use of acids, alkalis, corrosive substances or similar substances and the legal implications of this modification. The study was conducted from the contrast between the new Colombian legal figure, it's peers in the international arena, the numbers of people affected with these substances in Colombia and the criminal doctrine for personal injury that causes deformity. Some of the most important results are that the new offense punishes not only the material result (deformitydisfiguration of the victim) but also imposes a sanction for the means utilized to cause the result, however the Colombian criminal code used to sanction personal injuries solely on the basis of the result, now, this does not entail that injuries caused by this kind of means are ipso facto more harmful than the deformities caused by other type of instruments. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
35. EVALUACIÓN DE LA EFICIENCIA DE ROMPEDORES DE FLUIDOS DE FRACTURA BASE AGUA.
- Author
-
Carrascal, Fabián A., del Pilar Pachón, Zarith, and Molina V., Daniel
- Abstract
Copyright of Revista Fuentes, El Reventón Energético is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2014
36. Evaluation of pre-germinative treatments in seeds of Cereus jamacaru DC subsp. jamacaru (Cactaceae)
- Author
-
Tânia Kelly Mendes Feitosa, Elvis Estilak Lima, José Iago Muniz, Maria Edilania da Silva Serafim-Pereira, Aline Belém Tavares, Maria Arlene Pessoa da Silva, Suzana Gonçalves Santana Tavares, Marcos Aurélio Figueiredo dos Santos, Maria Haiele Nogueira da Costa, Karina Vieralves Linhares, João Pereira da Silva-Junior, Cícero dos Santos Leandro, Talina Guedes Ribeiro, Viviane Bezerra da Silva, José Weverton Almeida-Bezerra, and Natália Barbosa Campos
- Subjects
0106 biological sciences ,Germinación ,Germination ,Biology ,01 natural sciences ,law.invention ,Caatinga ,lcsh:Social Sciences ,Acetic acid ,chemistry.chemical_compound ,law ,lcsh:Science (General) ,Scarification ,Mandacaru ,General Environmental Science ,lcsh:LC8-6691 ,lcsh:Special aspects of education ,Cereus jamacaru ,Petri dish ,Dark cycle ,Acids ,Germinação ,04 agricultural and veterinary sciences ,biology.organism_classification ,Ácidos ,lcsh:H ,Horticulture ,chemistry ,Cactus ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,General Earth and Planetary Sciences ,010606 plant biology & botany ,lcsh:Q1-390 - Abstract
Cereus jamacaru DC subsp. jamacaru (mandacaru) is an endemic species in Brazil belonging to Cactaceae of great ecological importance, as it is a pioneer in the colonization of arid and inhospitable environments, and contributes directly to the food chain for its fruits highly appreciated by fauna. Therefore, this work aimed to evaluate, through chemical scarification, the germinative behavior of C. jamacaru subsp. jamacaru. The cactus seeds were collected in May 2016 in the city of Quixelô-CE-Brazil. The acids used in chemical scarification were acetic acid, hydrochloric acid, propionic acid and sulfuric acid for 5, 10 and 15 minutes. The seeds were placed in Petri dishes, and placed to germinate in a B.O.D. with a light/dark cycle of 12 hrs at 30 ºC. Daily readings were performed and analyzed: percentage of germination, Germination Speed Index (GSI) and mean germination time (Tm). The results indicate that acids negatively interfere in seed germination when compared to the control group, mainly acetic and propionic acid, since at the end of the experiment only 8% of the seeds germinated when subjected to acetic acid, and 4% to the propionic. In addition, there was also a significant increase in Tm. Thus, water is the best method of obtaining a higher percentage of germination of C. jamacaru subsp. jamacaru. Cereus jamacaru DC subsp. jamacaru (mandacaru) es una especie endémica en Brasil perteneciente a Cactaceae de gran importancia ecológica, ya que es pionera en la colonización de ambientes áridos e inhóspitos, y contribuye directamente a la cadena alimentaria por sus frutos muy apreciados por la fauna. Por tanto, este trabajo tuvo como objetivo evaluar, mediante escarificación química, el comportamiento germinativo de C. jamacaru subsp. jamacaru. Las semillas de cactus fueron recolectadas en mayo de 2016 en la ciudad de Quixelô-CE-Brasil. Los ácidos utilizados en la escarificación química fueron ácido acético, ácido clorhídrico, ácido propiónico y ácido sulfúrico durante 5, 10 y 15 minutos. Las semillas se colocaron en placas de Petri y se colocaron para germinar en un B.O.D. con un ciclo de luz/oscuridad de 12 ha 30 ºC. Se realizaron y analizaron lecturas diarias: porcentaje de germinación, índice de velocidad de germinación (IVG) y tiempo promedio de germinación (Tm). Los resultados indican que los ácidos interfieren negativamente en la germinación de las semillas en comparación con el grupo control, principalmente ácido acético y propiónico, ya que al final del experimento solo el 8% de las semillas germinaron al ser sometidas a ácido acético, y el 4% al propiónico. Además, también hubo un aumento significativo en Tm. Así, el agua es el mejor método para obtener un mayor porcentaje de germinación de C. jamacaru subsp. jamacaru. Cereus jamacaru DC subsp. jamacaru (mandacaru) é uma espécie endêmica do Brasil pertencente à Cactaceae de grande importância ecológica, por ser pioneira na colonização de ambientes áridos e inóspitos, e contribuir de forma direta na cadeia alimentar por seus frutos extremamente apreciados pela fauna. Sendo assim, este trabalho objetivou avaliar por meio de escarificação química o comportamento germinativo das sementes de C. jamacaru subsp. jamacaru. As sementes do cacto foram coletadas em maio de 2016 na cidade de Quixelô-CE-Brasil. Os ácidos utilizados nas escarificações química foram o ácido acético, ácido clorídrico, ácido propiônico e ácido sulfúrico durante 5, 10 e 15 minutos. As sementes foram acondicionadas em placas de Petri, e postas para germinar em câmara do tipo B.O.D. com um ciclo claro/escuro de 12 hrs a 30 ºC. Foram realizadas leituras diárias e analisadas: porcentagem de germinação, Índice de Velocidade de Germinação (IVG) e tempo médio para germinação (Tm). Os resultados apontam que os ácidos interferem de modo negativo na germinabilidade das sementes quando comparados com o grupo controle, principalmente o ácido acético e o propiônico, visto que ao final do experimento apenas 8% das sementes germinaram quando submetidas ao ácido acético, e 4% ao propiônico. Além disso, verificou-se também um aumentou significativo do Tm. Sendo assim, a água é o melhor método de se obter uma maior porcentagem de germinação de sementes de C. jamacaru subsp. jamacaru.
- Published
- 2020
37. DESCRIPCIÓN ANALÍTICA DE LOS ÁCIDOS PARA LA DIGESTIÓN QUÍMICA EN MUESTRAS BIOLÓGICAS EXPUESTAS A METALES
- Author
-
Argota Pérez, George and Iannacone, Jose Alberto
- Subjects
procedimiento ,ácidos ,digestión ,tejidos biológicos ,metales - Abstract
The aim of the study was to describe the analytical concentration of acids for chemical digestion in biological samplesexposed to metals. Hydrochloric acid (HCl), nitric acid (HNO3), perchloric acid (HClO4), sulfuric acid (H2SO4), boric acid (H3BO3), phosphoric acid (H3PO4) and hydroiodic acid (HI) were analyzed. Experimentally the acids were applied to the gills of the Gambusia punctata biomonitor (Poey, 1854) for the bioextraction of cadmium metal. Th e certifi ed reference sample, DOLT-3 (Dogfi sh Liver), was used for the analytical reliability of the results. Statistically signifi cant diff erences were found in the results of acid concentrations and the certifi ed reference value. Th e order of concentration was: HNO3 > H2SO4 > HClO4 > HCl > HI > H3PO4 > H3BO3. It is concluded that acids allow to extract bioaccumulated metals in biological tissues, but their application, not combined with other acids, will diff er signifi cantly with the true bioaccumulated value. Th e highest odds for metal extraction are with HNO3, H2SO4 and HClO4. El objetivo del estudio fue describir la concentración analítica de los ácidos para la digestión química en muestras biológicas expuestas a metales. Se analizó el ácido clorhídrico (HCl), ácido nítrico (HNO3), ácido perclórico (HClO4), ácido sulfúrico (H2SO4), ácido bórico (H3BO3), ácido fosfórico (H3PO4) y el ácido yodhídrico (HI). De forma experimental los ácidos se aplicaron en las branquias del biomonitor Gambusia punctata (Poey, 1854) para la bioextracción del metal cadmio. Se usó la muestra de referencia certifi cada: DOLT-3: (Dogfi sh Liver) para la confi abilidad analítica de los resultados. Se encontró diferencias estadísticamente signifi cativas en los resultados de las concentraciones de los ácidosy el valor de referencia certificado. El orden de concentración fue: HNO3 > H2SO4 > HClO4 > HCl > HI > H3PO4 > H3BO3. Se concluye que, los ácidos permiten extraer metales bioacumulados en los tejidos biológicos pero su aplicación no combinada con otros ácidos diferirá significamente con el verdadero valor bioacumulado. Las mayores probabilidades para la extracción de metales están con el HNO3, H2SO4 y el HClO4.
- Published
- 2020
38. DESARROLLO DE BIODIESEL A PARTIR DE MATERIAS PRIMAS CON UN ALTO CONTENIDO DE ÁCIDOS GRASOS LIBRES
- Author
-
Monserrat Aguilar, Carlos
- Subjects
Grado en Ingeniería Química-Grau en Enginyeria Química ,Comparación ,Catalizador ,Propiedades ,Transesterificación ,Materias ,Grasas ,INGENIERIA QUIMICA ,Contenido ,Primas ,Ácidos ,Grasos ,Biodiesel ,Purificación ,Alto - Abstract
[ES] Análisis de biodiesel obtenido mediante transesterificación de materias primas grasas con un contenido alto de ácidos grasos libres en su interior. Comparación de sus propiedades en función del catalizador utilizado(catalizador básico, sin catalizador y con distintos catalizadores ácidos) para su producción y el método de purificación para obtener el producto final., [EN] Analysis of biodiesel obtained by transesterification of fatty raw materials with a high content of free fatty acids inside. Comparison of its properties depending on the catalyst used (basic catalyst, without catalyst and with different acid catalysts) for its production and the purification method to obtain the final product.
- Published
- 2020
39. 2-Amino-3-methylpyridinium, 2-amino-4-methylbenzothiazolium and 2-amino-5-chloropyridinium salts. experimental and theoretical findings
- Author
-
Muhammad Usman Hanif, Ataualpa A. C. Braga, Muhammad Khalid, Ezzat Khan, Sara Figueirêdo de Alcântara Morais, and Muhammad Tahir
- Subjects
chemistry.chemical_classification ,Base (chemistry) ,010405 organic chemistry ,Hydrogen bond ,Organic Chemistry ,Supramolecular chemistry ,Salt (chemistry) ,ÁCIDOS ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Inorganic Chemistry ,Solvent ,chemistry ,Computational chemistry ,Reactivity (chemistry) ,Spectroscopy ,Electronic density ,Natural bond orbital - Abstract
Reaction between 2-amino-3-methylpyridine, 2-amino-4-methylbenzothiazole with salicylic acid, and 2-amino-5-chloropyridine with 3-chlorobenzoic acid were carried out and respective molecular salts 1–3 were obtained. During reactions, proton transfer from acid to endocyclic N of the base was observed. Structural elucidation of all compounds was carried out with the help of FT-IR and X-ray Diffraction for single crystals. The acid/base pairs in a molecular salt are held together with the help of H- and charge-assisted bonding and additional non-covalent bonding extend the supramolecular structure. All hydrogen bonds and secondary interactions have been discussed and a detailed comparison of experimental data with theoretical calculations through AIM, NBO and Wiberg bond index analysis has been made. The non-covalent character was mainly typified by positive values of Laplacian of electronic density. The theoretical studies demonstrate that other than classical H-bonds, the non-classical and secondary non-covalent interactions are very important to direct supramolecular structure of the respective molecular salt. The DFT calculations with solvent model SMD proved a good alternative to deduce the molecular salt formation when the 0>ΔpKa>3. Moreover, global reactivity descriptors (GRD) have been calculated utilizing the energies of FMOs. The calculated values for HOMO of compounds 1–3, -5.469, -5.642 and -6.435, respectively indicate that the compounds adopt the numerical order in terms of electron donation/Lewis basicity. The molecular salt formation is more feasible for heterosynthon 1 and least for 3.
- Published
- 2020
40. In vitro cytotoxicity assessment of ferulic, caffeic and p-coumaric acids on human renal cancer cells
- Author
-
Costa, João Guilherme
- Subjects
ÁCIDOS - Published
- 2020
41. Evaluación del proceso de obtención de biodiesel por catálisis heterogénea a partir de la grasa de pollo recuperada de los residuos generados en el proceso de cocción
- Author
-
Jefferson Rubio, Ana Rodriguez, Andrés Guayara, and Walberto Gallegos
- Subjects
ácidos ,grasos libres ,catálisis heterogénea ,transesterificación ,triglicéridos ,transesterification ,heterogeneous catalysis ,saponification ,triglycerides - Abstract
espanolSe analizaron las mejores condiciones experimentales para la obtencion de biodiesel a partir de la grasa de pollo recuperada del proceso de coccion de los pollos horneados que se comercializan en una cadena de supermercados de la ciudad de Quito. La transesterificacion se realizo por catalisis heterogenea comparando la efectividad del oxido de calcio y oxido de magnesio como catalizadores. La fase experimental se desarrollo con un diseno factorial 23, las variables de estudio fueron: la relacion molar alcohol-aceite, el tipo de catalizador y su porcentaje en peso. Las mejores condiciones de reaccion para ambos catalizadores resultaron de una relacion molar alcohol-aceite 12:1 y 1% de catalizador referido a la masa de grasa. Las maximas conversiones a biodiesel en los tratamientos con oxido de magnesio y de calcio fueron respectivamente del 22,17% y del 90,20%. El biocombustible obtenido bajo las mejores condiciones de operacion cumplio con los requerimientos establecidos por el Instituto Ecuatoriano de Normalizacion (INEN) de acuerdo a la norma INEN 1489 para el Diesel No.2, el cual es utilizado en automotores a diesel. EnglishThe investigation was oriented to determine the best experimental conditions to produce biodiesel using as raw material chicken grease that was recuperated from the baking process used in a local supermarket chain. The transesterification reaction compared the effectiveness of calcium and magnesium oxide as catalysts. A factorial design 23 was defined for the experimental face. The factors investigated were: molar proportion between methanol and oil, type of catalyst and it`s weight percentage. The best experimental conditions for both catalysts were a molar proportion methanol-oil 12:1 and 1% of catalyst referred to oil´s mass. The maximum yields obtained for treatments with magnesium and calcium oxide were 22, 17% and 90, 20% respectively. Regarding the biofuel´s quality; it fulfilled all the requirements of standard INEN 1489 for Diesel No.2 established by the Ecuadorian Service of Normalization INEN.
- Published
- 2017
42. APLICABILIDADE DOS PEELINGS QUÍMICOS EM TRATAMENTOS FACIAIS - ESTUDO DE REVISÃO.
- Author
-
MAIA GUERRA, FERNANDO MARCOS ROSA, KRINSK, GABRIELA GARCIA, CAMPIOTTO, LAÍS GUARNIERI, and FERNANDES GUIMARÃES, KARLA MARIANA
- Subjects
- *
CHEMICAL peel , *TREATMENT effectiveness , *AESTHETICS , *KERATOSIS , *SKIN diseases - Abstract
The use of acids in aesthetic changes has grown and, in order to prove its efficiency, several researches have been done, thus this study aimed to accomplish a bibliographic survey about the use of main agents of chemical facial peels, which makes possible to evidence its efficiency. It has been concluded that chemical peels show satisfactory results in some skin disorders such as: anthelasma, disseminated actinic keratosis, acne, rejuvenation, melasma, acne scarsand maintenance of dermatoses and agents used to perform these procedures are: Jessner's solution, salicylic acid, retinoic acid, mandelic acid, glycolic acid, hyaluronic, lactic acid phenol and trichloro acetic. However, the studies show few evaluation criteria and some describe the type of skin used in the treatments. [ABSTRACT FROM AUTHOR]
- Published
- 2013
43. The effect of ration forage proportions on the microbial ecology of the Rumen
- Author
-
Vihermäki, Rasmus and Vihermäki, Rasmus
- Abstract
Grovfoder utgör en stor del av kons foderintag och dess struktur är viktig för kons hälsa. En foderstat som till största delen innehåller kraftfoder främjar tillväxten av exempelvis Lactobacilli och Streptococcus bovis (S.bovis) som i sin tur producerar laktat. Laktat sänker pH i vommen och kan leda till vomacidos. Laktatomvandlande mikroorganismer kan inte omvandla laktat till flyktiga fettsyror (VFA) i samma hastighet och utsträckning som Lactobacilli producerar laktat. Vid idissling främjas salivproduktionen, ett av kons buffertsystem. Det finns ingen direkt koppling till att enbart grovfoder- och kraftfoderproportionerna har en inverkan på den totala koncentrationen av flyktiga fettsyror. Vid jämförelse av två grovfoder gav det ena en högre koncentration av flyktiga fettsyror (VFA) vilket indikerar att grovfoder- till kraftfoderproportionerna inte är den enda betydande faktorn. Däremot tycktes det finnas en koppling mellan foderstatens-kraftfoderandel och proportionerna propionat:acetat:butyrat. En ökad mängd kraftfoder i dieten gav upphov till protozotillväxt vilken i sin tur ger en högre andel butyrat. Grovfodrets partikelstorlek och grovfodertyp (gröda, konserveringsmetoder etc.) tycktes även ha en inverkan på koncentrationen av flyktiga fettsyror., Forage constitutes a large part of the cow’s feed intake and its structure is important for the cow’s health. A ration that mainly contains concentrates promotes the growth of, for example, Lactobacilli and Streptococcus bovis (S.bovis), which in turn produces lactate. Lactate lowers the pH in the rumen and may lead to rumen acidosis. Bacteria specialized in fermenting lactate into VFA are unable to convert at the same rate and extent as Lactobacilli can produce lactate. During rumination, saliva production is promoted, one of the cow’s buffer system. There is no connection that it is only the forage to concentrate ratio that has a direct effect on the total VFA concentration. When comparing two forage feeds, one gave a higher concentration of VFA which indicates that forage to concentrate ratio is not the only significant factor. However, the proportion of concentrate feed appeared to have an effect on the propionate:acetate:butyrate ratio. An increased amount of concentrate in the diet promotes the growth of protozoa which in turn give a higher proportion of butyrate. The particle size of the forage feed and which type of forage (crop, conservation method etc.) also appear to influence the VFA concentration.
- Published
- 2019
44. Morphological alterations on human radicular dentin after exposure to different fruit juice drinks.
- Author
-
Zandim, Daniela Leal, Martins, Cínthia Oliveira, Cavassim, Rodrigo, J£nior, Carlos Rossa Júnior, Abi-Rached, Ricardo Samih Georges Abi-Rached, and Sampaio, José Eduardo Cezar
- Subjects
CONFIDENCE intervals ,DENTIN ,DIET ,FRUIT ,STATISTICS ,U-statistics ,DATA analysis - Abstract
Copyright of Revista Odonto Ciencia is the property of EDIPUCRS - Editora Universitaria da PUCRS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2011
- Full Text
- View/download PDF
45. Claude-Louis Berthollet.
- Author
-
Wisniak, Jaime
- Subjects
- *
CHEMISTS , *THEORY of combustion , *PHLOGISTON , *CHLORINE , *HYDROCYANIC acid - Abstract
Claude-Louis Berthollet (1748-1822) was the first prominent chemist to reject the phlogiston theory and accept the oxygen theory of combustion. His experiments showed that prussic acid and hydrogen sulfide did no contain oxygen thus disproving the generality of Lavoisier's oxygen theory of acidity. His discoveries about chlorine and its bleaching properties were a decisive step in advancing the chemical industrial revolution in general and the textile industry in particular. [ABSTRACT FROM AUTHOR]
- Published
- 2008
46. Evaluation of Multi-Mixtures of Acids for the Sample Preparation of Organic Soil Amendments for Multi-Element Determination by ICP OES
- Author
-
Thiago R.L.C. Paixão, Luiza G. R. Albuquerque, Pedro Vitoriano de Oliveira, and Alexandre M. Fioroto
- Subjects
inorganic chemicals ,Cadmium ,Magnesium ,Phosphorus ,010401 analytical chemistry ,Soil Science ,chemistry.chemical_element ,ÁCIDOS ,Manganese ,010501 environmental sciences ,01 natural sciences ,0104 chemical sciences ,Chromium ,chemistry ,Inductively coupled plasma atomic emission spectroscopy ,Sample preparation ,Agronomy and Crop Science ,Arsenic ,0105 earth and related environmental sciences ,Nuclear chemistry - Abstract
A method for the simultaneous determination of aluminum (Al), arsenic (As), calcium (Ca), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), phosphorus (P), lead (...
- Published
- 2017
47. Prenatal Exposure to Perfluoroalkyl Substances and Adiposity in Early and Mid-Childhood
- Author
-
Antonia M. Calafat, Matthew W. Gillman, Ana M. Mora, Emily Oken, Sheryl L. Rifas-Shiman, Sharon K. Sagiv, Thomas F. Webster, and Xiaoyun Ye
- Subjects
Male ,Health, Toxicology and Mutagenesis ,Physiology ,010501 environmental sciences ,Toxicology ,Medical and Health Sciences ,01 natural sciences ,WEIGHT (MASS) ,0302 clinical medicine ,Medicine ,030212 general & internal medicine ,Child ,Adiposity ,Pediatric ,2. Zero hunger ,Fluorocarbons ,ÁCIDOS ,ÍNDICE DE MASA CORPORAL ,Alkanesulfonic Acids ,Massachusetts ,Maternal Exposure ,Child, Preschool ,INFANCY ,Environmental Pollutants ,Female ,PRENATAL CARE ,BODY WEIGHT ,Caprylates ,medicine.medical_specialty ,Prenatal care ,Body weight ,INFANCIA ,03 medical and health sciences ,Clinical Research ,Internal medicine ,Humans ,Obesity ,PESO CORPORAL ,Preschool ,Prenatal exposure ,Nutrition ,0105 earth and related environmental sciences ,BODY MASS INDEX ,business.industry ,Extramural ,Research ,Prevention ,Public Health, Environmental and Occupational Health ,ACIDS ,medicine.disease ,PESO (MASA) ,CUIDADO PRENATAL ,Endocrinology ,business ,Body mass index ,Environmental Sciences - Abstract
Background: Few studies have examined whether prenatal exposure to perfluoroalkyl substances (PFASs) is associated with childhood adiposity. Objective: We examined associations of prenatal exposure to PFASs with adiposity in early and mid-childhood. Methods: We measured plasma PFAS concentrations in 1,645 pregnant women (median, 9.6 weeks gestation) enrolled in Project Viva, a prospective pre-birth cohort study in Massachusetts (USA), between 1999 and 2002. We assessed overall and central adiposity in 1,006 children in early childhood (median, 3.2 years) and 876 in mid-childhood (median, 7.7 years) using anthropometric and dual X-ray absorptiometry (DXA) measurements. We fitted multivariable linear regression models to estimate exposure-outcome associations and evaluated effect modification by child sex. Results: Median (25–75th percentiles) prenatal plasma perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), and perfluorononanoate (PFNA) concentrations in children assessed in early childhood were 5.6 (4.1–7.7), 24.8 (18.4–33.9), 2.4 (1.6–3.8), and 0.6 (0.5–0.9) ng/mL, respectively. Among girls, each interquartile range increment of prenatal PFOA concentrations was associated with 0.21 kg/m 2 (95% CI: –0.05, 0.48) higher body mass index, 0.76 mm (95% CI: –0.17, 1.70) higher sum of subscapular and triceps skinfold thickness, and 0.17 kg/m 2 (95% CI: –0.02, 0.36) higher DXA total fat mass index in mid-childhood. Similar associations were observed for PFOS, PFHxS, and PFNA. We observed null associations for boys and early-childhood adiposity measures. Conclusions: In this cohort, prenatal exposure to PFASs was associated with small increases in adiposity measurements in mid-childhood, but only among girls. Antecedentes: pocos estudios han examinado si la exposición prenatal a sustancias perfluoroalquilo (PFAS) está asociada con la adiposidad infantil. Objetivo: Examinamos las asociaciones de la exposición prenatal a los PFAS con la adiposidad en la niñez temprana y media. Métodos: medimos las concentraciones plasmáticas de PFAS en 1.645 mujeres embarazadas (mediana, 9,6 semanas de gestación) inscritas en Project Viva, un estudio prospectivo de cohortes prenatal en Massachusetts (EE. UU.), Entre 1999 y 2002. Evaluamos la adiposidad general y central en 1.006 niños en la primera infancia (mediana, 3,2 años) y 876 en la infancia media (mediana, 7,7 años) mediante mediciones antropométricas y de absorciometría de rayos X duales (DXA). Ajustamos modelos de regresión lineal multivariable para estimar las asociaciones exposición-resultado y evaluamos la modificación del efecto por sexo del niño. Resultados: La mediana (percentiles 25-75) de perfluorooctanoato plasmático prenatal (PFOA), sulfonato de perfluorooctano (PFOS), sulfonato de perfluorohexano (PFHxS) y perfluorononanoato (PFNA) en niños evaluados en la primera infancia fue de 5,6 (4,1-7,7), 24,8 ( 18,4 a 33,9), 2,4 (1,6 a 3,8) y 0,6 (0,5 a 0,9) ng / ml, respectivamente. Entre las niñas, cada incremento del rango intercuartílico de las concentraciones prenatales de PFOA se asoció con 0,21 kg / m 2 (IC del 95%: –0,05, 0,48) mayor índice de masa corporal, 0,76 mm (IC del 95%: –0,17, 1,70) mayor suma de subescapular y espesor del pliegue cutáneo del tríceps, y 0,17 kg / m 2 (IC del 95%: –0,02, 0,36) índice de masa grasa total DXA más alto en la infancia media. Se observaron asociaciones similares para PFOS, PFHxS y PFNA. Observamos asociaciones nulas para los niños y las medidas de adiposidad en la primera infancia. Conclusiones: En esta cohorte, la exposición prenatal a los PFAS se asoció con pequeños aumentos en las mediciones de adiposidad en la infancia media, pero solo entre las niñas. Antecedentes: Poucos estudos examinaram se a exposição pré-natal a substâncias perfluoroalquil (PFASs) está associada à adiposidade infantil. Objetivo: Nós examinamos associações de exposição pré-natal a PFASs com adiposidade na primeira e na metade da infância. Métodos: Medimos as concentrações plasmáticas de PFAS em 1.645 mulheres grávidas (mediana, 9,6 semanas de gestação) inscritas no Projeto Viva, um estudo de coorte prospectivo pré-nascimento em Massachusetts (EUA), entre 1999 e 2002. Avaliamos a adiposidade geral e central em 1.006 crianças na primeira infância (mediana, 3,2 anos) e 876 na meia-infância (mediana, 7,7 anos) usando medidas antropométricas e absortometria de raio-X duplo (DXA). Ajustamos modelos de regressão linear multivariável para estimar as associações de exposição-desfecho e avaliamos a modificação do efeito por sexo da criança. Resultados: As concentrações de perfluorooctanoato plasmático pré-natal (PFOA), perfluorooctano sulfonato (PFOS), perfluorohexano sulfonato (PFHxS) e perfluorononanoato (PFNA) em crianças avaliadas na primeira infância foram 5,6 (4,1-7,7), 24,8 ( 18,4–33,9), 2,4 (1,6–3,8) e 0,6 (0,5–0,9) ng / mL, respectivamente. Entre as meninas, cada incremento do intervalo interquartil das concentrações pré-natais de PFOA foi associado a 0,21 kg / m 2 (IC 95%: -0,05, 0,48) índice de massa corporal mais alto, 0,76 mm (IC 95%: -0,17, 1,70) maior soma do subescapular e espessura da dobra cutânea tricipital, e 0,17 kg / m 2 (IC 95%: –0,02, 0,36) índice de massa gorda total DXA mais alto no meio da infância. Associações semelhantes foram observadas para PFOS, PFHxS e PFNA. Observamos associações nulas para meninos e medidas de adiposidade na primeira infância. Conclusões: Nesta coorte, a exposição pré-natal a PFASs foi associada a pequenos aumentos nas medidas de adiposidade no meio da infância, mas apenas entre as meninas. Boston University School of Public Health, United States Universidad Nacional, Costa Rica Harvard Medical School and Harvard Pilgrim Health Care Institute, United States Harvard T.H. Chan School of Public Health, United States National Center for Environmental Health, United States University of California, United States Instituto Regional de Estudios en Sustancias Tóxicas
- Published
- 2017
48. The Use of the Jigsaw Method and Sensory Experiments in Improving the Teaching and Learning of Acids and Bases in High School
- Author
-
Florambel, Athus Torres, Lopes, Gisele Simone, and Lima, Isaias Batista
- Subjects
Método Jigsaw ,Ácidos ,Bases (Química) ,Química-Estudo e ensino - Abstract
Aiming to connect the precepts of cooperative activity that assists students in the development of interpersonal skills, positive interdependence, individual responsibility, as well as the use of the motivating power of the experimental classes that arouse curiosity and instigate the students to the investigative process, is that it proposes to application of a teaching strategy that makes use of the cooperative learning method jigsaw, associated to sensory experiments involving the senses (taste, smell and vision). The research is carried out with high school students (3rd grade) from a state school in Maracanaú CE, on the subject of acids and bases. For the validation of the method will be used two semistructured questionnaires, one to analyze the contribu tions of the class in the proposed model to the learning of the subject acids and bases and another to analyze acceptance of the method, where the students expose their perceptions about the influence of the cooperative work in their learning, organization and relevance of the stages, didactic resources used and the topic addressed. The observed results show that the proposed class caused significant advances in the acquisition of knowledge by the students, about the theme addressed, and was very well accep ted, including reducing the resistance of students to perform reading activities. Therefore, it is concluded that combining different didactic methods with the teaching and learning process can result in an important instrument for stimulating students' le arning, with potential to accommodate the various forms of student learning. O método de aprendizagem cooperativa Jigsaw foi utilizado neste trabalho como estratégia de ensino com o objetivo de unir os preceitos da atividade cooperativa , que auxilia os alunos no desenvolvimento de habilidades interpessoais, interdependência positiva e responsabilidade individual, ao uso do poder motivador das aulas experimentais que despertam a curiosidade e instigam os alunos ao processo investigativo. O método foi associado a experimentos sensoriais envolvendo os sentidos (paladar, olfato e visão) para o ensino do tema de ácidos e bases . A pesquisa foi realizada com alunos do ensino médio (3ª série) de uma escola da rede estadual de ensino em Maracanaú CE . Para a validação do método, foram utilizados dois questionários semiestruturados, um para analisar as contribuições da aula no modelo proposto para a aprendizagem do tema ácidos e bases e outro para analisar a aceitação do método, no qual os alunos expõem suas percepções sobre a influência do trabalho cooperativo em sua aprendizagem, organização e relevância das etapas, recursos didáticos utilizados e tema abordado. Os resultados observados mostram que a aula proposta provocou avanços significativos na aquisição, pelos alunos, dos saberes relacionados ao tema abordado e que foi muito bem aceito, inclusive reduzindo a resistência dos alunos para a realização de atividades de leitura. Portanto, conclui-se que aliar diferentes métodos didáticos ao processo de ensino e aprendizagem pode resultar em um importante instrumento de estímulo à aprendizagem dos alunos, com potencial para abrigar as diversas formas do aluno aprender.
- Published
- 2019
49. Analysis of the surface energy of orthodontic wires from different alloys subjected to acid exposure
- Author
-
Adriazola Ique, Manuel Martin [UNESP], Universidade Estadual Paulista (Unesp), Mendonça, Marcos Rogério de [UNESP], and Delbem, Alberto Carlos Botazzo [UNESP]
- Subjects
energia livre de superficie ,Fios ,ácidos ,acid ,ángulo de contato - Abstract
Submitted by MANUEL MARTIN ADRIAZOLA IQUE (adriazola87@hotmail.com) on 2019-05-21T18:07:24Z No. of bitstreams: 1 Martin Adriazola.pdf: 7691921 bytes, checksum: 23a89bbb7e6752aa137f2d23f8dc04b9 (MD5) Approved for entry into archive by Claudio Hideo Matsumoto null (claudio@foa.unesp.br) on 2019-05-21T20:30:00Z (GMT) No. of bitstreams: 2 adriazolaique_mm_me_araca_int.pdf: 7691921 bytes, checksum: 23a89bbb7e6752aa137f2d23f8dc04b9 (MD5) adriazolaique_mm_me_araca_par.pdf: 259849 bytes, checksum: 82ece39decdd6c16144956e5452ef017 (MD5) Made available in DSpace on 2019-05-21T20:30:00Z (GMT). No. of bitstreams: 2 adriazolaique_mm_me_araca_int.pdf: 7691921 bytes, checksum: 23a89bbb7e6752aa137f2d23f8dc04b9 (MD5) adriazolaique_mm_me_araca_par.pdf: 259849 bytes, checksum: 82ece39decdd6c16144956e5452ef017 (MD5) Previous issue date: 2019-03-03 O objetivo deste estudo foi avaliar in vitro a energia de superfície livre e rugosidade de superfície de ligas metálicas sob desafios de soluções ácidas. Para o estudo foram utilizados 270 corpos de prova representados por segmentos de fios retangulares de 0,019” x 0,025” - 3 marcas comerciais (GAC, American Orthodontics e Orthoclassic) foram divididas em 3 grupos de diferentes soluções sendo 90 para água deionizada, 90 para ácido cítrico e 90 para ácido fosfórico, dentro dos grupos de solução dividiu-se em 30 de aço inoxidável, 30 de níquel titânio e 30 titânio molibdênio. Cada grupo de análise (n=10) foi imerso em meio a cada solução por 72 horas a 37º C e agitação de 130 rpm. A análise de ESL foi avaliada através do dispositivo goniômetro para interpretação do ângulo de contato avaliando a variável. As médias foram submetidas ao teste ANOVA e as comparações ao Tukey a 5% de significância. A superfície da liga de TMA apresentou maior valor de energia de superfície (p
- Published
- 2019
50. Estudo da síntese de um análogo de alfa-ácido presente em lúpulo e correlação do comportamento eletroanalítico com o amargor da cerveja
- Author
-
Paolla Lorrayne Maciel Rodrigues Almeida, Munoz, Rodrigo Alejandro Abarza, Sousa, Raquel Maria Ferreira de, Rezende junior, Celso de Oliveira, and Fernandes, David Maikel
- Subjects
Lúpulo ,Eletrochemical ,Eletroquímica ,Hop ,Cerveja ,Amargor ,IBU ,Ácidos ,Beer ,Química ,Acids ,CIENCIAS EXATAS E DA TERRA [CNPQ] ,Bitterness - Abstract
CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico FAPEMIG - Fundação de Amparo a Pesquisa do Estado de Minas Gerais Embora o lúpulo tenha sido inicialmente usado como conservante na cerveja, esse introduziu amargor e um sabor agradável a ela, razão pela qual foi grande a sua aceitação e assim se substituiu outras matérias-primas antes utilizadas na bebida. O sabor característico se deve tanto ao óleo essencial como as resinas encontradas nas glândulas de lupulina. Os α-ácidos presentes na resinas são de grande interesse na industria cervejeira. Durante a fervura no processo de obtenção da bebida, os α-ácidos são isomerizados em iso-α-ácidos, conferindo o típico sabor amargo. Esse trabalho teve como propósito sintetizar a molécula 2-acetil-3,5,6-trihidroxi-4,6-dimetilciclohex-2,4-dienona para ser utilizada como padrão analítico na medida do amargor em cervejas, uma vez que esse padrão não é encontrado para venda. Nesse sentido, trata-se de uma alternativa para análise dos α-ácidos, que atualmente possuem custos elevados, e por outro lado para as microcervejarias que estão em plena expansão no Brasil, a análise de α-ácidos seria mais acessível com o uso de técnicas com baixo custo, alta precisão, facilidade e rapidez nos resultados. Até o momento, a molécula não foi totalmente sintetizada, não sendo possível ainda mostrar os resultados obtidos de quantificação do amargor. Entretanto, o trabalho mostra que o extrato de lúpulo, bem como uma cerveja com grau de amargor elevado (IBU: 100), apresentaram fenômeno oxidativo. O lúpulo apresentou potencial de oxidação por voltametria de pulso diferencal em +1,16 V, enquanto que a cerveja em +1,20 V. Essa diferença ocorre pois os α-ácidos são isomerizados a iso-α-ácidos nas cervejas. Através da análise por espectrometria de massas foi possível confirmar essa diferença de composição entre o extrato do lúpulo e a cerveja. Although hops were initially used as a preservative in beer, it introduced bitterness and a pleasant taste to it, which is why its acceptance was great and thus replaced other raw materials previously used in the drink. The characteristic taste is due to essential oils and resins found in the lupulin glands. The α-acids from resins are the most interesting to the brewing industry. During boiling in the process of obtaining the beverage, α-acids are isomerized in iso-alpha-acids, conferring the typical bitter taste. The purpose of this work was to synthesize the 2,4-diacetyl-3,4-dihydroxy-5-methylcyclopent-2-anone molecule to be used how analytical standard in the quantification of hop from beer, since this standard is not found for sale. Therefore, it would be an alternative for the analysis of the α-acids, which currently has a high cost, and on the other hand, the microbreweries are in full expansion in Brazil, the analysis of α-acids would be more accessible to these companies by techniques with low cost, high accuracy and ease and speed in results. So far the molecule has not been fully synthesized. It is not yet possible to show the results obtained from bitter quantification. However, the work shows that hop extract, as well as a beer with a high degree of bitterness (IBU: 100), presented oxidative phenomena. The hops presented oxidation potential by pulse voltammetry at +1.16 V, while beer at +1.20 V. This difference occurs due to the presence of the alpha-acids being isomerized in beers. Through the mass spectrometry analysis it was possible to confirm this difference in composition between the hop extract and the beer. Dissertação (Mestrado)
- Published
- 2019
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.