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p-Nitrophenol (pNP) is a widely used compound for analytical determinations of several esterases (EC. 3.1.1.X), including lipases (E.C. 3.1.1.3). Most enzymatic measurements employ pNP derivatives such as esters, which are broken down by enzymatic hydrolysis, releasing pNP that is quantified by its absorbance at 410 nm. Although this type of methods was developed a few decades ago, the spectrophotometric analysis of pNP requires analytical measurements of pH and temperature to achieve reliable determinations. The aim of this paper is to offer a graphical update of how pH and temperature affect the p-nitrophenol absorbance at different wavelengths in lipase emulsified media, due to its relevance for the quantitative determination of lipase activity using spectrophotometric methods. To highlight the importance of each variable involved in this analysis, we dissolved pNP in emulsified media (for lipase activity quantification) at several pH values from 4.00 to 11.00, and measured its absorbance in a range of 270 nm – 500 nm and at several temperatures from 25°C to 50°C. The absorption patterns of pNP under the established conditions were graphed in 3D plots. The constructed 3D plots showed that, regardless of the temperature, below pH 6.00, pNP predominantly absorbs at 317 nm, due to the greater abundance of its protonated form, which is completely predominant at pH 3.50 and below. On the other hand, at pH 10.0 and above, the major absorption occurs at about 401 nm, confirming that the equilibrium is completely shifted to the pNP anionic form. These results also indicate that close to neutral pH value pNP, it displays a temperature dependence effect, increasing absorbance to 410 nm at higher temperatures. Due to many analytical determinations of enzymatic activities, the release of pNP is carried around pH 7.00. It is necessary to consider the determinant role of both pH and temperature over these measurements, how these variables must be strictly controlled, and how the calibration curves and blanks should take the reaction media pH and temperature into account. El p-nitrofenol (pNP) es un compuesto ampliamente utilizado para la determinación analítica de esterasas (EC. 3.1.1.X), incluidas las lipasas (E.C. 3.1.1.3). La mayoría de las mediciones enzimáticas emplean sus derivados, tales como ésteres, que se descomponen por hidrólisis, liberando pNP que se cuantifica por su absorbancia a 410 nm. Aunque, este tipo de métodos se desarrolló hace algunas décadas, el análisis espectrofotométrico de pNP requiere mediciones precisas de pH y temperatura, para lograr determinaciones confiables. El objetivo de este trabajo es ofrecer una actualización gráfica de cómo el pH y la temperatura afectan la absorbancia de p-nitrofenol a diferentes longitudes de onda en medios emulsionados para ensayos con lipasas, debido a su relevancia para la determinación cuantitativa de la actividad de las lipasas bajo métodos espectrofotométricos. Para resaltar la importancia de cada variable en este análisis, se disolvió pNP en medios emulsionados (para la cuantificación de la actividad de la lipasa) a varios valores de pH de 4.00 a 11.00 y se midió su absorbancia en un rango de 270 nm a 500 nm a varias temperaturas en el rango de 25 °C a 50 °C. El comportamiento químico de pNP bajo estas condiciones se correlacionó mediante la construcción de gráficos tridimensionales. Como resultado, los gráficos 3D construidos experimentalmente, mostraron que, independientemente de la temperatura, por debajo de pH 6.00 el pNP absorbe principalmente, a 317 nm, debido a la mayor abundancia de su forma protonada que es completamente predominante a pH 3.50 e inferiores. Por otro lado, a pH 10.0 y superiores, el equilibrio se desplaza completamente a la forma aniónica pNP, que absorbe a 410 nm. Nuestros datos confirman que en valores de pH cercano a la neutralidad, el pNP muestra un efecto de dependencia a la temperatura, aumentando la absorbancia a 410 nm a temperaturas más altas. Debido a muchas determinaciones cuantitativas de las actividades enzimáticas, el pNP se libera en un medio de reacción de alrededor de pH 7.00. Es necesario recordar el papel determinante del pH y la temperatura sobre estas mediciones y cómo estas variables deben ser estrictamente consideradas O p-nitrofenol (pNP) é um composto amplamente utilizado para a determinação analítica de esterases (EC. 3.1.1.X), incluindo lipases (E.C. 3.1.1.3). A maioria das medições enzimáticas utiliza seus derivados, como ésteres, que se decompõem por hidrólise, liberando pNP quantificado por sua absorvência a 410 nm. Embora esses tipos de métodos tenham sido desenvolvidos há algumas décadas, a análise espectrofotométrica de pNP requer medições precisas de pH e temperatura para obter determinações confiáveis. O objetivo deste trabalho é oferecer uma atualização gráfica de como o pH e a temperatura afetam a absorvência do p-nitrofenol em diferentes longitudes de onda em meios emulsionados para ensaios de lipase, devido a sua relevância para a determinação quantitativa da atividade das lipases sob métodos espectrofotométricos. Para destacar a importância de cada variável nesta análise, o pNP foi dissolvido em meio emulsionado (para quantificação da atividade da lipase) em vários valores de pH de 4,00 a 11,00 e sua absorvência foi medida na faixa de 270 nm a 500 nm a várias temperaturas na faixa de 25 °C a 50 °C. O comportamento químico do pNP nessas condições foi correlacionado mediante a construção de gráficos tridimensionais. Como resultado, os gráficos 3D construídos experimentalmente mostraram que, independentemente da temperatura, abaixo de pH 6,00, o pNP absorve principalmente a 317 nm, devido à maior abundância de sua forma protonada, que é completamente predominante em pH 3,50 e inferiores. Por outro lado, o pH 10,0 e superiores, o equilíbrio muda completamente para a forma aniônica pNP, que absorve a 410 nm. Nossos dados confirmam que em valores de pH próximos à neutralidade, o pNP mostra um efeito de dependência da temperatura, aumentando a absorvência a 410 nm em temperaturas mais altas. Em virtude de muitas determinações quantitativas de atividades enzimáticas, o pNP é liberado em um meio de reação de cerca de pH 7,00. É necessário lembrar o papel determinante do pH e da temperatura nessas medições e como essas variáveis devem ser estritamente consideradas Universidad Nacional, Costa Rica Escuela de Química

10 páginas To optimize cattle consumption and nutrition, it is essential to know the botanical characteristics of the pastures they consume. Therefore, the objective of the present research work was to evaluate the floristic composition, the productive performance of pastures and the productivity of dairy cattle on cattle farms in the inter-Andean valley of Cajamarca. The research was carried out in 10 dairy farms, under a mixed production system, with a stocking rate between 1.8 and 5.3 animal units per hectare. The floristic composition of the forage floor was determined using the “step transect” method to determine the desirable and undesirable species for livestock, considering the age of the pasture from 35 to 45 days and before grazing. A total of seven dominant species were found, of which Lolium multiflorum L. - “Cajamarquino ecotype”, Trifolium pratense and Trifolium repens are desirable species for livestock and represent on average 44.84% of the forage floor, the difference being represented by weeds or undesirable species such as: Pennisetum clandestinum, Rumex obtusifolius, Taraxacum officinale and Plantago major. Also, the average biomass yield was 3.33 t. ha-1 with protein levels of 9.96%. The forage yield is low, which affects the animal carrying capacity and consequently the production of the dairy cows, ranging from 5.83 to 16.22 kg milk/day on average, showing very variable and with low profitability. Abstract. Introduction. Materials and Methods. Results and Discussion. Conclusion. Bibliography.

Background: There is currently no gold standard biomaterial for the treatment of periodontal intrabony defects (PIDs). One of the current options is the use of platelet-rich fibrin (PRF). Objective: To determine the clinical effect of PRF in the treatment of PID through a systematic review and meta-analysis. Materials and Methods: A literature search was conducted up to February 2017 in the following biomedical databases: Pubmed, Embase, Scielo, Science Direct, SIGLE, LILACS and in the Cochrane Central Register of Clinical Trials. The selection criteria included: randomized clinical trials published in the last 5 years, reporting clinical effects (probing depth, clinical insertion level or gingival recession), with a follow-up time equal to or greater than 6 months, and sample size larger than or equal to 10 patients reporting the use of PRF as a treatment for PID. The methodological quality of the studies was analyzed using the Cochrane Handbook of Systematic Reviews of Interventions as a reference. Results: The search strategy yielded 20 articles. A reduction in probing depth and an increase in clinical insertion level or a reduction in gingival recession is reported, when using PRF alone or in combination with another biomaterial or substance that stimulates tissue regeneration. Conclusion: The literature suggests that the use of PRF in the treatment of PIDs has a beneficial clinical effect when compared to control treatments. © 2017, Universidad de Concepcion. All rights reserved.

In this study, the effect of two alternative growing substrates (corncob and Azolla anabaena) on some vegetative parameters (days to emergence, stem diameter, plant height and root volume) in seedlings of broccoli hybrid Coronado were evaluated. Both materials were ground and used according to the following treatments: 100% corncob (T1), 100% Azolla (T2), 50% corncob + Azolla 50% (T3), corncob 75% + Azolla 25% (T4), 25% corncob + Azolla 75% (T5) and then compared to a commercial substrate (BM2) (T6). Substrates were uniformly mixed, deposited in germination trays and watered at field capacity. Additionally, physic-chemical characteristics were determined in the different substrates used for broccoli seedling production. Stem diameter, height plant and root volume showed to be statistically higher in seedlings grown in commercial substrate (0.18 cm, 5.27 cm and 0.61 cm3, respectively) followed by those seedlings grown in 100% Azolla (0.17 cm, 4.92 cm and 0.49 cm3, respectively) (p< 0.001). Seedlings growing in substrates with higher corncob proportion showed lower values in these vegetative parameters. Based on our results, Azolla showed potential to be used as a seed substrate for production of broccoli seedlings, thus decreasing the use of peat and consequently the production costs in nurseries.

The aim of this review is to present production alternatives based on animal welfare standards and good management practices on broiler and posture breeding. The excessive intensive production of eggs and chicken meat comes from the demand for food from a growing world population. And it has forgotten good animal husbandry and management practices. Which causes an imbalance of the sympathetic nervous system and adrenal medullary tissue that control the response of the poultry to stress, raising catecholamine levels inducing the release of glucose causing liver, heart and neuronal failure. these effects become visible due to the increase of diseases since the immune system is depressed, food intake decreases, oxytocin inhibition, which results in reduced reproduction and even death of the poultry. The incorporation of animal welfare standards imposed in intensive breeding, as well as, the production of eggs and meat under production systems (grazing) and backyard production become a sustainable alternative that maximizes the welfare of the poultry

Introduction: One of the consequences of periodontitis is periodontal intrabony defects (PID). Various biomaterials have been used for its treatment, but there is still no biomaterial considered as the gold standard. Current research is focused on the use of platelet-rich plasma (PRP) for the treatment of PID. Objective: To determine the clinical effect of PRP in the treatment of PID through a systematic review with meta-analysis. Materials and Methods: A literature search was conducted until February 2017 in the biomedical databases: Pubmed, Embase, Scielo, Science Direct, SIGLE, LILACS, IBECS, and the Cochrane Central Register of Clinical Trials. The criteria for the selection of the studies, which were randomized clinical trials, were the following: articles or papers published in the last 5 years, reporting clinical effects, with a follow-up time equal to or greater than 6 months, and a sample size equal to or greater than 10 patients reporting the use of PRP as a treatment for PID. The methodological quality of the studies was analyzed using the Cochrane Handbook of Systematic Reviews of Interventions as a reference. Results: The search strategy yielded nine articles reporting a reduction in probing depth and gingival recession, and an increase in clinical insertion level when using PRP alone or in combination with another biomaterial. Conclusion: The reviewed literature suggests that the use of PRP in the treatment of PID has a positive clinical effect. © 2017, Universidad de Concepcion. All rights reserved.

Se realizaron análisis de dos estados de madurez (de cosecha y fisiológica) del fruto. Los contenidos de vitamina C oscilaron entre 4.0 y 5.0 mg; los °Brix, entre 8.7 y 13.5; la acidez, entre 0.63 y 0.96; el pH entre 2.4 y 3.0; el índice de esfericidad, entre 0.86 y 1.06; los azúcares reductores, entre 0.29 y 0.33 mg/mg fruta. Se procesó el fruto artesanalmente y mostró un rendimiento mayor al 30%. Los resultados indican que el fruto tiene buenas posibilidades para su transformación en jugos, néctares, salsas y mermeladas. ABSTRACT Physical- chemical, bromatologychal, phytochemical analysis and handmade potencial transformation of Spondias dulcis. Were carried out analysis in two states of maturity (crop and physiological). The correlation variance and analyses showed significant differences in the two states of coloration taking a level of significancia of 5%. The fruit presents change morfological of ovoid to semi-ovoid for the matter concentration in their diameters means and superior in the fruits of maturity of consumption, reaching weight that ranked from 66.9 to 117g for the first state and 93.6 to 248g in the second state, conformed in its majority by pulp (68.1 and 71.75% respectively). An increase was presented in the content of fatty acids in pulp and decrease of carbohydrates and ash in pulp and shell with the maturity change. In general there were not presence of toxic components that can affect their consumption. Products overcome 34% of efficiency wich is seen a considerable yield and the transformation level it is handmade. Key words: Spondias dulcis, Amberella, Pacific plum, Anacardiaceae, maturity, agroindustrial sector, handicrafts, phytochemistry, agroindustrial handmade transformation, food technology

En el Perú, el crecimiento económico continuo de 6% promedio anual durante el período 2001-2007 resulta poco acompasado con un mayor bienestar anivel microeconómico. Durante el mismo período de análisis, los niveles de pobreza disminuyeron únicamente 2,7 puntos porcentuales frente a los 27,5 puntos porcentuales de crecimiento del PBI. Por lo tanto, la búsqueda de tasas de crecimiento económico elevadas resulta insuficiente para lograr una reducción significativa de los niveles de pobreza y desigualdad de ingresos. En este sentido, el camino eficaz está relacionado con la promoción de iniciativas orientadas a la generación de riqueza en las regiones con potencial de crecimiento. Para que las iniciativas orientadas a generar riqueza tengan mayor impacto en la reducción de la pobreza, es necesario modificar el marco institucional de forma tal que se genere un mejor clima para las inversiones. El presente artículo rescata los principales aportes teóricos así como experiencias internacionales y peruanas que de alguna manera pueden vincular a los pobres con oportunidades para un crecimiento más inclusivo., The average growth of Peru GDP reached 6 per cent during the 2001-2007 period. However this growth was not in parallel with the microeconomic wellbeing. During this years, the poverty rate decreased 2.7 percentage points in contrast the GDP growth of 27.5 percentage points. As a consequence, searching for high economic growth rates is not enough for reaching a significant decrease of poverty and inequality. In this sense, an effective way might be the promotion of wealth growth initiatives in specific regions with high potential. In order to get a real impact in the poverty reduction it is necessary to change the institutional framework which foster a better environment for the private investment. This article is based on theorical findings and empirical case studies based on local and international experiences. The idea is to suggest ways by which it is possible to link the poor with opportunities in a context of a more inclusive economic growth.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:23:36Z No. of bitstreams: 0 Made available in DSpace on 2014-05-27T11:23:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-25 Twelve elephant grass genotypes were evaluated in a randomized blocks design with three repetitions. The experimental parcel was of 4 lines with 3m of length, spaced of 1 m and fertilized with 100 kg of P2O5, 100 kg of N, 60 kg of K2O and 25 kg of micronutrients/ha. Significant differences were observed among the genotypes for neutral detergent fiber (FND), acid detergent fiber (FAD) and lignin. The genotypes CNPGL 92-70-02, CNPGL 91-25-01 and CNPGL 93-32-02 showed low values for FND, FAD and lignin, simultaneously, outstanding between the others. There were no significant differences in the levels of dry matter and crude protein contents and in in vitro dry matter digestibility between the genotypes. UENF-CCTA-LZNA, Av. Alberto Lamego, 2000, Campos dos Goytacazes. Rio de Janeiro. 28015-620 UNESP, Botucatu/SP UNESP, Botucatu/SP

A geomechanics based methodology was utilized to analyze sand production problems as well as the amount of damage caused to the wells of the Southern Area 2 sector of the Ceuta field in Lake Maracaibo, Venezuela. Sand production in this field was not originally expected since the reservoir is composed of a well consolidated sand at depths larger than 16,000 feet and with rocks having an unconfined compressive strength larger than 6000 psi. Geomechanically speaking, sand production is caused when the destabilizing stresses on the formation are larger than the resistance due to formation strength. However, certain well operations can affect the destabilizing stresses as well as the formation strength. Therefore geomechanics must be used together with proper operational procedures because many operational details can also have a profound effect on the occurrence of sand production. One of the most important factors has to do with the production practices involving proper choke sizes and excessive choke changes. Sand production data gathered in the Ceuta field was analyzed using a geomechanical framework of understanding to predict well damage and problems during choke changes. The data defines 3 different stages of sand production for wells in this field. Each stage has a particular behavior and different problems associated with them. The sand production data was integrated together with the fluid production data to calculate the amount of accumulated sand production. A simple spherical model was developed to calculate cavity size around the casing utilizing the accumulated sand production. It was found that a well could produce large quantities of sand before total well failure. Total well failure appears to be related to the size of the cavities around the casing which leave it unsupported and also to erosive damage to the casing done by the sand laden fluids. The sand producing data was then used to diagnose the stage at which the sand production problem occurs and to change choke utilization practices in order to minimize sand production. Special laboratory geomechanical tests on core from the area and full wave sonic logging information was used to generate a model which calculates the critical drawdown for the problematic sands. Critical drawdown control has been the solution for most wells. Some other solutions such as hydraulic fracture and highly deviated wells in the correct direction have also been utilized.

Thermal and mechanical rock properties were evaluated with special laboratory tests and logs to analyze a Steam Assisted Gravity Drainage (SAGD) project by MARAVEN S.A. (now part of PDVSA Exploración y Producción) in the heavy oil Tía Juana field on the eastern side of Lake Maracaibo, Venezuela. This SAGD project is the first application of this technology in Venezuela and consisted of two parallel horizontal wells on top of each other where steam is injected in the upper well and oil is produced in the lower well. Special coring equipment and procedures were utilized in a specific well to obtain a low perturbation core. Dipole sonic logging was successfully used to obtain a continuos profile of P and S wave velocities in these extremely loose unconsolidated sands to serve as calibration with the laboratory tests. A special series of laboratory tests were carried out in this core to determine thermal and mechanical properties which will be useful to characterize these extremely loose unconsolidated sand reservoirs under the varied conditions of temperature and pressure encountered in this project. Basic thermal properties such as thermal conductivity, specific heat and thermal expansion were specifically determined with modern equipment and techniques for the first time in Venezuela. Triaxial strength tests were carried at 72°F and 330°F to see the effect of high temperatures due to steam injection on stress-strain behavior, modulus and friction angle. This reservoir characterization at high temperatures was fundamental in analyzing problems of borehole stability during drilling as well as production in the injector and producer wells because of the mutual interaction due to the proximity of both wells. Of specific importance was the limiting flow rate of the steam injection well to eliminate hydraulic fracturing and the limiting production rate of the producing well to eliminate sand production and stability problems. The interaction and stability of both holes was evaluated with a fully coupled finite element program using Biot's poroelastic theory. This program was used to determine stability, stress and pore pressure values around the injector and producer wells under steady state conditions. The geomechanical analysis helped in defining the safe operating limits for the dual horizontal wells was useful to explain the behavior of some SAGD wells already in production in Tia Juana field and to plan for future ones.