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Abstract Objectives To compare mortality rates between GCA patients and the general population in Spain, and to identify associated factors influencing mortality. Methods ARTESER, a multicenter registry by the Spanish Society of Rheumatology, includes GCA patients from June 2013 to March 2019. Demographic, clinical, imaging, histological and mortality data were collected retrospectively. Only patients with at least one year of follow-up were included for analysis. The mortality rates were expressed as the number of deaths per 1000 person-years, with 95% confidence interval (CI) by sex and age group. Kaplan-Meier method was performed for survival analysis. The factors influencing mortality were analyzed using Cox regression model. Results A total of 1200 patients with GCA were analyzed, with a mean (SD) follow-up of 2.18 (1.53) years. The overall five-year cumulative mortality rate (95%CI) was 37.86 (31.75-43.96) per 1000 patients/year. The cumulative mortality rate was significantly higher in males than females (59.04vs29.06; p

El objetivo de esta investigación es analizar la conectividad vial en relación con los indicadores de analfabetismo, desnutrición, viviendas sin acceso al agua, pobreza no monetaria y acceso a internet. En la metodología, para la elaboración cartográfica de conectividad vial, se utilizó la ponderación por distancia o inverse distance weighting (IDW) en el software de ArcGis 10.8, en tanto los indicadores para los distritos se han extraído desde GeoPerú. Los resultados indican que la conectividad vial desempeña un papel crucial en el desarrollo socioeconómico de los distritos. Aquellos con una alta conectividad, como Moche, Huancán y Perené, presentan índices más bajos de analfabetismo, desnutrición, viviendas sin acceso a agua potable, pobreza no monetaria y hogares sin internet en comparación con los distritos de baja conectividad, como El Porvenir, Santo Domingo de Acobamba y Pichanaqui. Se concluye que la infraestructura vial es un factor clave para reducir la desigualdad y mejorar las condiciones de vida en áreas menos desarrolladas.

Diversas experiencias de pequeñas unidades de riego muestran que, a partir de organizaciones sociales, normas, usos y costumbres, y arreglos consensados para la toma de decisiones han logrado acuerdos vinculantes en torno a temas de interés colectivo, tales como sistemas autogestivos del agua, en donde mediante un nivel organizativo se llevan a cabo todas las actividades del sistema de riego, como distribución del agua, mantenimiento, resolución de conflictos, monitoreo y vigilancia. El objetivo del estudio fue conocer la capacidad autogestiva de la sociedad de usuarios “Pozo Zamorano” en el manejo del agua a partir de los principios de diseño característicos de los recursos de uso común (RUC) de larga duración. Los resultados muestran que la gestión del recurso está dada por normas y reglamentos internos, sistemas de sanciones económicas que han sido establecidas de forma común por los usuarios, para permitir un buen manejo y orden dentro de la sociedad. Los puntos de diseño propuestos por Ostrom para las organizaciones administradas por los mismos usuarios están presentes en la organización de la sociedad “Pozo Zamorano” y se pueden considerar con un desempeño alto. La condición autogestiva de los socios regantes les ha permitido dar continuidad a la actividad agrícola, de la cual depende la mayoría de los habitantes de la comunidad.

RESUMEN Se trata de una mujer de 57 años con antecedentes de linfoma MALT gástrico y nefritis intersticial atribuida a la quimioterapia. En el estudio de diarrea crónica encontramos un páncreas atrófico, con deficiencia de elastasa. Se sospecha pancreatitis autoinmune. Se comprueba una elevación importante de IgG4 sérica. Con estos datos se procede a la revisión de la biopsia renal realizada 10 meses antes. La inmunohistoquímica revela un número significativo de células plasmáticas productoras de IgG4. En los pulmones la paciente tiene nódulos, adenopatías e infiltrados. El diagnóstico al que llegamos es Enfermedad relacionada con IgG4. ABSTRACT This is a 57-year-old woman with a history of gastric MALT lymphoma and interstitial nephritis attributed to chemotherapy. In the study of chronic diarrhea, we found an atrophic pancreas, with elastase deficiency. Autoimmune pancreatitis is suspected. There is a significant elevation of serum IgG4. With these data we proceed to the review of the renal biopsy performed 10 months before. Immunohistochemistry reveals a significant number of IgG4-producing plasma cells. In the lungs the patient has nodules, lymphadenopathy and infiltrates. The diagnosis we reached is IgG4-related disease.

Abstract Background Perfectionism is considered a vulnerability factor for eating disorders. However, the role of perfectionism in binge eating needs clarification due to notably inconsistencies between studies. The purpose to this study was to conduct a systematic review and meta-analysis to estimate the perfectionism-binge eating association. Method Systematic review was performed according to the PRISMA 2020 statement. Four databases (Web of Science, Scopus, PsycINFO and Psicodoc) were searched to identify studies published until September 2022. The literature search yielded 30 published articles (N = 9392) that provided 33 independent estimations of the correlation between the two variables. Results Random-effects meta-analysis revealed a small-to-moderate positive average effect size between general perfectionism and binge eating (r + = .17) with a large heterogeneity. Perfectionistic Concerns showed a significant small-to-moderate relationship with binge eating (r + = .27), whereas Perfectionistic Strivings presented a negligible relationship with binge eating (r + = .07). Moderator analyses showed that the age, the type of the sample, the study design, and the tools for assessing both variables were statistically associated with the perfectionism-binge eating effect sizes. Conclusions Our findings suggest that Perfectionism Concerns are closely associated with binge eating symptomatology. This relationship might be moderated by certain variables, especially by the clinical or non-clinical nature of the sample and the instrument employed to assess binge eating.

Mexico is the main producer of avocado (Persea americana Mill.), contributing 31% of the world supply, which provides the country with an annual income of more than 2 billion dollars. The increase in national production is the result of a larger cultivated area, and not an increase in yields. In the State of Mexico, Mexico around 10 thousand hectares are cultivated with avocado trees, although 77% of the producers do not have specialized technical advice that offers reliable information on crop nutrition. This lack of advice and technical support detracts from volume and quality of production. The objective of this research was to carry out the nutritional diagnosis of an avocado orchard in Tejupilco, State of Mexico, Mexico, through the Compositional Nutrient Diagnosis (CND), and to generate specific fertilization recommendations for the study area, for which leaf and soil analyses were carried out. Each nutrient determined in the leaf analysis (N, P, K, Ca, Mg, S, Fe, Mn, Zn, Cu, and B) was compared with its optimal concentration according to literature. The CND yielded relative deficiency or excess indices that determined the order of nutritional limitation. Zn, B, S, and K deficiencies were detected in all sampled areas, while P, Mn, and Cu were deficient only in some areas. N, Ca, Mg, and Fe did not show nutritional limitation. Recommendations were formulated to address each of the nutritional deficiencies and the problem of sodicity revealed by the soil analysis. This is the first work in which the CND is used to assess the nutritional situation of avocado orchards in the world.

Abstract Aim To systematically evaluate the efficacy of different topical treatments for PVC‐related phlebitis in hospital in‐patients. Design A systematic review and meta‐analysis. Methods A selection was made of experimental and quasi‐experimental studies published in English or Spanish. These should provide data on the degree of phlebitis, pain and infiltration (means and standard deviations, mainly) of hospitalized patients with phlebitis secondary to peripheral venous catheter. All those studies that reflected systemic or exclusive prevention treatments were excluded. Searches were from inception to April 2020. The date of data collection was from December 2020 to May 2021. The selection criteria were based on the PICOS model. Risk of bias was assessed using the Cochrane Collaboration tool. Results Twelve studies (726 patients) met the inclusion criteria. With respect to the decrease in the degree of phlebitis, was found ichthammol glycerine, followed by heparinoids. As for degree of pain, sesame oil obtained the most marked reduction. In terms of degree of infiltration, heparinoids and ichthammol glycerine were the only products to achieve a statistically significant reduction. The most important limitations are the low quantity and quality of the trials included. Insufficient data are available to draw valid conclusions about the efficacy of any treatment.

Abstract Background Advantages of meta-analysis depend on the assumptions underlying the statistical procedures used being met. One of the main assumptions that is usually taken for granted is the normality underlying the population of true effects in a random-effects model, even though the available evidence suggests that this assumption is often not met. This paper examines how 21 frequentist and 24 Bayesian methods, including several novel procedures, for computing a point estimate of the heterogeneity parameter ( $${\tau }^{2}$$ τ 2 ) perform when the distribution of random effects departs from normality compared to normal scenarios in meta-analysis of standardized mean differences. Methods A Monte Carlo simulation was carried out using the R software, generating data for meta-analyses using the standardized mean difference. The simulation factors were the number and average sample size of primary studies, the amount of heterogeneity, as well as the shape of the random-effects distribution. The point estimators were compared in terms of absolute bias and variance, although results regarding mean squared error were also discussed. Results Although not all the estimators were affected to the same extent, there was a general tendency to obtain lower and more variable $${\tau }^{2}$$ τ 2 estimates as the random-effects distribution departed from normality. However, the estimators ranking in terms of their absolute bias and variance did not change: Those estimators that obtained lower bias also showed greater variance. Finally, a large number and sample size of primary studies acted as a bias-protective factor against a lack of normality for several procedures, whereas only a high number of studies was a variance-protective factor for most of the estimators analyzed. Conclusions Although the estimation and inference of the combined effect have proven to be sufficiently robust, our work highlights the role that the deviation from normality may be playing in the meta-analytic conclusions from the simulation results and the numerical examples included in this work. With the aim to exercise caution in the interpretation of the results obtained from random-effects models, the tau2() R function is made available for obtaining the range of $${\tau }^{2}$$ τ 2 values computed from the 45 estimators analyzed in this work, as well as to assess how the pooled effect, its confidence and prediction intervals vary according to the estimator chosen.

Nowadays, production is configured around Global Value Chains, and countries’ involvement in those has become important objectives for achieving economic upgrading. However, social outcomes are neither equally distributed between countries, nor among social classes within countries. Indeed, GVCs and the potential gains of countries' involvement in them, yield uncertain implications of the effects of globalization on inequality within countries. In this context, the aim of this work is to analyze the link between the performance of countries in GVCs (measured trough participation and position) and the levels of intra-country inequality. In more depth, we focus on Europe (specifically, EU28 countries), as it offers a wide and cohesive scenario of developed countries in which to test the effects of linking into GVCs on internal inequalities. We get a positive effect of participation in GVCs on increasing intra-country inequality, while more upstream positions are linked to decreases in income inequality. Besides, if we differentiate by geographical area, Western and Southern European countries would achieve higher reductions in inequality than Northern countries by moving towards more upstream positions.

Corrosion and scaling in metal pipelines are the major issues in the exploitation of geothermal sources. Geothermal fluids are complex mixtures consisting of dissolved gases and high-salinity solutions. This creates very aggressive environments primarily due to the high concentrations of carbon dioxide (CO2), hydrogen sulfide (H2S), chlorides, and other chemical species. Besides, the high temperature of the brines also increases corrosion rates, which can lead to failures related to stress and fatigue corrosion. On the other hand, reinjection of cooled brine exiting the heat exchanger favors the onset of scaling, since the chemicals dissolved in geothermal waters may tend to precipitate promoting inorganic depositions on the casing. Corrosion and scaling phenomena are difficult to detect visually or monitor continuously. Standard techniques based on pH, temperature pressure, electrical resistance measurements, chemistry composition, and physical properties are habitually applied as indirect methods for corrosion rate control. These methods, however, lack enough robustness for accurate and reliable measuring of the corrosion behavior of materials. To address this issue, a novel system has been proposed for the continuous monitoring of corrosion degradation caused by the effect of the geothermal brines. The present work aims to design, develop, and validate a dedicated electrochemical-based test system for online and onsite monitoring of the corrosion rate and scaling growth occurring on different materials exposed to real operating conditions. This system uses non-standard methods based on electrochemical impedance spectroscopy (EIS) to obtain quantitative data related to the material quality. It can be used to track the condition of the pipeline, reducing the operation and maintenance (O&M) costs and shutdown times. By providing early corrosion rate data, this system allows the prediction of failures in critical units of the plant.

Abstract Background Systemic lupus erythematosus (SLE) has been associated with atherosclerotic cardiovascular disease (CV) and an altered lipid profile. High levels of apolipoprotein C-III (ApoC3) are associated with elevated triglyceride levels and an increased risk of CV. In the present study, we aimed to study circulating ApoC3 in patients with SLE and describe its relationship with the manifestations of the disease. Methods This is a cross-sectional study that included 186 patients with SLE. Disease-related data, CV comorbidity, full lipid profile, and serum levels of ApoC3 were assessed. A multivariable regression analysis was performed to study how ApoC3 was related to SLE features. Results Classic CV risk factors were significantly and strongly associated with circulating ApoC3. After a fully multivariable analysis that included classic CV risk factors and lipid profile molecules, SLICC damage (beta coef. 0.10 [95% CI 0.02–0.19] mg/dl, 0.020) and Katz severity (beta coef. 0.11 [95% CI 0.03–0.19] mg/dl, p = 0.011) indices and SLEDAI activity score (beta coef. 0.05 [95% CI 0.05–0.08] mg/dl, p = 0.004) were all independently associated with higher levels of circulating ApoC3. Conclusion Among SLE patients, disease activity, severity, and disease damage are independently associated with higher ApoC3 serum levels.

Se comparan suelos de cafetales con diferente pendiente y manejo durante un año. En cuatro cafetales (manejo órgano-mineral, agroecológico con mínimo manejo, manejo convencional y manejo agroecológico) se llevó a cabo el muestreo de suelo por estación del año y se cuantificó materia orgánica, carbono orgánico, N, P, K, CIC, pH, textura y respiración microbiana. Los suelos con manejo agroecológico presentaron valores más altos de materia orgánica (10.09%) y respiración microbiana (621 µg C.CO2). Por estación del año varió carbono orgánico, N, materia orgánica y respiración microbiana. La materia orgánica y respiración microbiana fue similar en cafetales con misma pendiente. No hay una relación directa de calidad del suelo y rendimiento de café. En Tlapacoyan la producción de café disminuye y la sustentabilidad y calidad de los suelos también.

No necesita de un resumen.

Background: Visual involvement is the most feared complication of giant cell arteritis (GCA). Information on the efficacy of tocilizumab (TCZ) for this complication is scarce and controversial. Objective: We assessed a wide series of GCA treated with TCZ, to evaluate its role in the prevention of new visual complications and its efficacy when this manifestation was already present before the initiation of TCZ. Design: This is an observational multicenter study of patients with GCA treated with TCZ. Methods: Patients were divided into two subgroups according to the presence or absence of visual involvement before TCZ onset. Visual manifestations were classified into the following categories: transient visual loss (TVL), permanent visual loss (PVL), diplopia, and blurred vision. Results: Four hundred seventy-one GCA patients (mean age, 74 ± 9 years) were treated with TCZ. Visual manifestations were observed in 122 cases (26%), of which 81 were present at TCZ onset: PVL ( n = 60; unilateral/bilateral: 48/12), TVL ( n = 17; unilateral/bilateral: 11/6), diplopia ( n = 2), and blurred vision ( n = 2). None of the patients without previous visual involvement or with TVL had new episodes after initiation of TCZ, while only 11 out of 60 (18%) patients with PVL experienced some improvement. The two patients with diplopia and one of the two patients with blurred vision improved. Conclusion: TCZ may have a protective effect against the development of visual complications or new episodes of TVL in GCA. However, once PVL was established, only a few patients improved.

This work describes the use of the breath figure (BF) method for the fabrication of photoactive porous polymer films and the characterization of their responsive to photo stimulus. The films incorporate self-assembled photoactive polymers and ZnS nanoparticles (NPs). The effect of both components on the optical and morphological properties of the films were analyzed. Films with a hexagonally ordered pattern were obtained. The photoactive polymer was prepared by grafting the photochromic component 1-(2-hydroxyethyl)-3,3-dimethylindoline-6-nitrobenzopyran (SP) to polystyrene-block-polymethacrylic acid (PS-b-PMMA). ZnS NPs were incorporated into the polymer solution, and the films were prepared using spin-coating on glass substrates before subjecting them to the BF method. The hollow footprints were obtained before introducing the ZnS NPs in order to maintain the necessary conditions for hexagonal film growth. Accordingly, the SEM micrographs of the films prepared in the presence of ZnS NPs displayed a loss in the pore arrangement as a consequence of the interaction between SP moiety and NPs. The light-emitting properties of films were characterized by blue and violet colors when exposed to UV light under fluorescence. Progress in the field of breath-figure formation and its application, such as exemplified in this work, leads to functional structures with suitable applications in chemistry and materials science. It is expected that such microstructured polymeric films will have interesting applications in photonic and optoelectronic devices.

Resumen: Se ha comprobado que los temas de actualidad y los puntos claves para el desarrollo de la neumología y cirugía torácica son comunes independientemente de la comunidad autónoma valorada, aunque con realidades bien distintas a la hora de afrontarlos. Esto hace que este tipo de foros, además de enriquecedores al poner de manifiesto las diferencias territoriales existentes, sean necesarios para diseñar estrategias de futuro comunes que puedan ser lideradas desde SEPAR a nivel nacional. Abstract: Current issues and key points in the development of pulmonology and thoracic surgery are the same among the different autonomous communities of Spain, although each community takes a very different approach in addressing these issues. As a result, forums that shed light on territorial differences are not only informative, but are also essential for designing common SEPAR-led strategies for the future at a countrywide level.

BackgroundCorticosteroids are the cornerstone of the treatment of patients with COVID-19 admitted to hospital. However, whether corticosteroids can prevent respiratory worsening in hospitalized COVID-19 patients without oxygen requirements is currently unknown.AimsTo assess the efficacy of methylprednisolone pulses (MPP) in hospitalized COVID-19 patients with increased levels of inflammatory markers not requiring oxygen at baseline.MethodsMulticenter, parallel, randomized, double-blind, placebo-controlled trial conducted in Spain. Patients admitted for confirmed SARS-CoV-2 pneumonia with raised inflammatory markers (C-reactive protein >60 mg/L, interleukin-6 >40 pg/ml, or ferritin >1,000 μg/L) but without respiratory failure after the first week of symptom onset were randomized to receive a 3-day course of intravenous MPP (120 mg/day) or placebo. The primary outcome was treatment failure at 14 days, a composite variable including mortality, the need for ICU admission or mechanical ventilation, and clinical worsening, this last parameter defined as a PaO2/FiO2 ratio below 300; or a 15% decrease in the PaO2 from baseline, together with an increase in inflammatory markers or radiological progression. If clinical worsening occurred, patients received tocilizumab and unmasked corticosteroids. The secondary outcomes were 28-day mortality, adverse events, need for ICU admission or high-flow oxygen, length of hospital stay, SARS-CoV-2 clearance, and changes in laboratory parameters.ResultsA total of 72 patients were randomized and 71 patients were analyzed (34 in the MPP group and 37 in the placebo group). Twenty patients presented with treatment failure (29.4 in the MPP group vs. 27.0% in the placebo group, p = 0.82), with no differences regarding the time to treatment failure between groups. There were no cases of death or mechanical ventilation requirements at 14 days post-randomization. The secondary outcomes were similar in MPP and placebo groups.ConclusionsA 3-day course of MPP after the first week of disease onset did not prevent respiratory deterioration in hospitalized COVID-19 patients with an inflammatory phenotype who did not require oxygen.

In contemporary times, water resources have become increasingly scarce and suffer from anthropogenic pollution sources with an organic and inorganic origin that are products of industrial, agricultural, and everyday waste. Contamination with heavy metals and dyes in wastewater is considered a risk for water sources that can leak into underground and surface sources, leading to increased biological and chemical contamination. The pollutant removal process is performed by adsorption treatment methods, which is the most common method, and it is considered an effective method with a high and economical removal rate.In this review, we discuss the use of biobased hydrogel adsorbents in the removal of organic dyes and metal ions from water. The literature indicates that hydrogels exhibit rapid absorption kinetics and a dye removal absorption capacity that can reach more than 100 mg/g and sometimes more than 2000 mg/g, with a metal adsorption capacity ranging from 38 mg/g to more than 440 mg/g. These results are discussed and compared by taking into account hydrogel materials that contain biopolymers such as alginate, chitosan or both. In general, absorption depends mainly on biobased materials, which have a natural origin and can be utilized to synthesize hydrogels to remove pollutants, dyes and heavy metals. Chitosan and alginate are prominent materials for this use and they can be incorporated with other components to obtain hydrogels or nanocomposite materials with different efficacies to remove dyes and metal ions.

The resistance that Triple-Negative Breast Cancer (TNBC), the most aggressive breast cancer subtype, develops against radiotherapy is a complex phenomenon involving several regulators of cell metabolism and gene expression; understanding it is the only way to overcome it. We focused this review on the contribution of the two leading classes of regulatory non-coding RNAs, microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), against ionizing radiation-based therapies. We found that these regulatory RNAs are mainly associated with DNA damage response, cell death, and cell cycle regulation, although they regulate other processes like cell signaling and metabolism. Several regulatory RNAs regulate multiple pathways simultaneously, such as miR-139-5p, the miR-15 family, and the lncRNA HOTAIR. On the other hand, proteins such as CHK1 and WEE1 are targeted by several regulatory RNAs simultaneously. Interestingly, the study of miRNA/lncRNA/mRNA regulation axes increases, opening new avenues for understanding radioresistance. Many of the miRNAs and lncRNAs that we reviewed here can be used as molecular markers or targeted by upcoming therapeutic options, undoubtedly contributing to a better prognosis for TNBC patients.

La investigación desarrollada con 12 estudiantes de licenciatura en matemáticas tuvo como fin dar respuesta a la pregunta científica ¿cómo son las relaciones entre la resolución de problemas y la demostración en algebra abstracta, manifestada por profesores de matemáticas en formación? Para la recolección de información se implementaron seis actividades didácticas, dos encuestas semiestructuradas, como complemento para triangular la información se tomó la opinión a docentes de álgebra abstracta y finalmente se aplicó a los estudiantes una encuesta de satisfacción. Para el análisis de datos se tuvo en cuenta la teoría de la Dualidad, Necesidad y Razonamiento Repetido de Harel y Sowder, así como la propuesta de Schoenfeld sobre resolución de problemas. Los hallazgos muestran que tanto al resolver problemas como al demostrar teoremas se encuentran patrones iguales en el abordaje, el uso de representaciones, los procesos de solución, justificación y verificación. Los resultados muestran que en el contexto del algebra abstracta no se encuentran diferencias en los procesos de solución de problemas y demostración de teoremas, por el contrario, son procesos que se complementan uno al otro, además hay incidencia de factores psicológicos, didácticos y creencias sobre la matemática que repercuten en el desarrollo de ambos procesos.

Abstract Background The present protocol was designed for a systematic review and meta-analysis aimed at determining the association of telomere length with substance use disorders with the exclusion of nicotine addiction, and to identify potential moderators of the effect of telomere length. Such methodological information may provide guidance to improve the quality of future research on this important topic. Methods Potential studies will be identified through electronic databases (PubMed/MEDLINE, EMBASE, PsycINFO, and Web of Science) up from inception onwards. The inclusion criteria will include published or unpublished observational studies (cohort, case–control, and cross-sectional studies) reporting telomere length in adult patients with substance use disorder compared with a control group. Non-human studies or other study designs such as reviews, case-only, family-based, and/or population studies with only healthy participants will be excluded, as well as those focused solely on nicotine addiction. The main outcome will be telomere length in adults with substance use disorder (primary) and, specifically, in those with alcohol use disorder (secondary). Two investigators will independently evaluate the preselected studies for possible inclusion and will extract data following a standardized protocol. Disagreements will be resolved by consensus. The risk of bias of all included studies will be assessed using the Newcastle–Ottawa Quality Assessment Scale for non-randomized studies. Data will be converted into standardized mean differences as effect size index, and random-effects models will be used for the meta-analysis. Cochran’s Q statistic, I 2 index, and visual inspection of the forest plot will be used to verify study heterogeneity. Subgroup analyses and meta-regressions will be conducted to ascertain heterogeneity. Several sensitivity analyses will be conducted to address the influence of potential confounding factors. Publication bias will be examined using the “funnel plot” method with Duval and Tweedie’s trim-and-fill method and Egger test. Discussion This systematic review will assess the association of telomere length with substance use disorders aside from nicotine addiction. Systematic review registration PROSPERO registration number CRD42019119785

El objetivo de la investigación fue comparar la respuesta de cuatro cultivares de Kale a cuatro diferentes sustratos, un factorial 4 x 3 con un diseño experimental completamente al azar. Semillas de los cultivares de Kale, Chinese, Siberiano, Rusian y Etiopia se germinaron en charolas con peat moss y se trasplantaron en 1) tezontle rojo de 0.3 cm, 2) una mezcla de vermicompost-perlita-tierra de monte y 3) una mezcla bocashi-perlita-tierra de monte. Cuatro meses después del trasplante se cosecho y se hicieron evaluaciones de nitratos en savia, y variables de desarrollo para comparar entre los sustratos. La respuesta de los cultivares fue diferente, en cada cultivar se presentó una respuesta diferente de desarrollo en función del sustrato en donde creció, el tezontle y la solución Steiner fue el suministro más balanceado de la nutrición y a la que respondieron todos los cultivares. El cultivar Etiopia fue el único cultivar que no presento diferencias estadísticas en las variables de estudio en función del sustrato. El Kale es un cultivo fácil de producir y una alternativa viable para la producción y consumo entre la población urbana y rural como fuente nutrimental y fácil de producir. DOI: https://doi.org/10.54167/tecnociencia.v15i1.757

Hydrogels with ion exchange properties were synthesized from compounds derived from wood biopolymer hemicellulose and from commercial vinyl monomers to be tested as active materials for the removal of Cu(II), Cr(VI), and As(V) ions. The hemicellulose O-acetyl galactoglucomannan (GGM) was used as the precursor material, and through a transesterification reaction, GGM was converted into a macromonomer GGM–glycidyl methacrylate (GGM-GMA). Subsequently, the GGM-GMA macromonomer, containing more than one methacrylate group, was used as a crosslinking agent in the synthesis of hydrogels through free-radical polymerization reactions in combination with a 2-acrylamido-2-methyl-1-propanesulfonic acid monomer to produce a cation exchange hydrogel. Also, (3-acrylamidopropyl)trimethylammonium chloride monomer was applied together with the GGM-GMA to form hydrogels that can be used as anion exchange hydrogel. The hydrogels were characterized by Fourier transform-infrared (FT-IR), 1H-NMR spectroscopy, and thermogravimetric analysis (TGA), as well as derivative thermogravimetry (DTG). The microstructure of the hydrogels was characterized by scanning electron microscopy (SEM) analysis with X-ray microanalysis energy-dispersive spectroscopy (EDS). The results obtained regarding the absorption capacity of the Cu(II), Cr(VI), and As(V) ions were studied as a function of the pH value and the initial concentration of the metal ions in the solutions. Absorption was carried out in consecutive batches, and it was found that the poly(GGM-GMA/AMPSH) hydrogel reached an absorption capacity of 90 mg g–1 for Cu(II). The poly(GGM-GMA/APTACl) hydrogel reached values of 69 and 60 mg g–1 for Cr(VI) and As(V) oxyanions, respectively. Tests with polymer blends (mixtures of anionic and cationic hydrogels) were also carried out to remove Cu(II), Cr(VI), and As(V) ions from multi-ionic solutions, obtaining satisfactory results.

In the present research, nanocomposites based on copper (I) oxide poly(1-vinyl-2—pyrolidone-co-itaconic acid) nanostructures (Cu2O/p(NVP-co-AI)) were synthesized by the electrodeposition method using the copolymer p(NVP-co-AI) as a stabilizing agent in the reduction of Cu+2 to Cu+. The chemical and physical properties of the nanostructures were characterized by techniques such as scanning electron microscopy, infrared (IR) spectroscopy, Raman and ultraviolet-visible spectrophotometry. The obtained nanostructures are mainly a mixture of agglomerated nanospheres with a diameter of approximately 78 to 91 nm, with an alternation of nanolaminar structures, composed of copper (I) oxide species. In the case of the Cu2O/p(NVP-co-AI) nanocomposite, it was observed a decrease in the carbon-oxygen vibration links of the carbonyl groups in IR intensity for the polymer when it was dissolved in the electrolytic solution, which indicates that interactions are produced by the carbonyl groups with the Cu2O species. In addition, bandgap values of 1.80 and 1.63 eV were estimated by the Kubelka–Munk method for Cu2O and Cu2O/p(NVP-co-AI) samples, respectively.

La milpa, asociación integrada por maíz (Zea mays L.), frijol (Phaseolus spp.) y calabaza (Cucurbita spp.), es el sistema de producción de alimentos más importante para el autoabasto de las familias que viven en zonas rurales de México. El objetivo de este estudio fue evaluar la sustentabilidad de agroecosistemas de milpa en una comunidad de la Sierra Norte de Oaxaca. La evaluación se realizó en 12 parcelas de milpa, divididas en dos grupos de contraste por sus prácticas de manejo, y sus respectivas unidades familiares. Con base en la metodología Marco para la Evaluación de Sistemas de Manejo de Recursos Naturales Incorporando Indicadores de Sustentabilidad (MESMIS) se seleccionaron 15 indicadores de sustentabilidad que se midieron a través de una encuesta, principalmente. Los agroecosistemas se reagruparon mediante un análisis multivariado realizado con la paquetería Rcmdr del software libre R. Los indicadores se transformaron a una escala estandarizada de 0 a 100 mediante el método de intervalo de referencia. El análisis multivariado reclasificó a los agroecosistemas en tres conglomerados, que se diferenciaron principalmente por el indicador relación beneficio-costo neta, y distinguió dos casos atípicos. Los elementos que le dotan de mayor sustentabilidad a los agroecosistemas evaluados son la biodiversidad agrícola y circundante, el contenido de materia orgánica del suelo, y la baja dependencia de insumos químicos y apoyos gubernamentales. No obstante, la sustentabilidad de estos sistemas se ve amenazada por la variabilidad climática y por la incertidumbre del relevo generacional.