Resumen En este estudio se evaluó la proporción de especies arbóreas nativas respecto a las introducidas en bosques urbanos de seis zonas rurales de Hualahuises, Nuevo León (noreste de México). Para el análisis de varianza se utilizó la prueba de proporciones con un nivel de confianza de 0.95 mediante el comando prop.test en R. Se registraron 252 individuos de 32 especies distribuidas en 29 géneros y 19 familias. La familia Fabaceae fue la mejor representada con siete especies. De todos los taxones, 19 son nativos (59.37 %) y 13 introducidos (40.63 %). De acuerdo con su origen, 77.79 % de los individuos son nativos y 22.21 % introducidos. Referente a sus dimensiones, las diferencias porcentuales son mayores: las nativas representan 91.69 % de área basal, 92.36 % de área de copa, 92.22 % de área superficial de la copa y 96.78 % de volumen de copa, mientras que las no nativas presentan valores inferiores a 9.00 %. Prosopis laevigata, seguida de Vachellia farnesiana y Ebenopsis ebano presentaron los valores estructurales más altos. Las tres son nativas pertenecientes a la familia Fabaceae y juntas conforman 44.05 % de la abundancia y 63.71 % del Índice de Valor de Importancia Urbano. Con base en el análisis de varianza, las especies nativas resultaron tener mayores valores de riqueza, área basal y área superficial de copa que las introducidas en las localidades evaluadas.

Abstract In this study, the proportion of native vs. introduced tree species in urban forests of six rural areas of Hualahuises, Nuevo León (Northeast Mexico) was evaluated. For the analysis of variance, the proportions test was used with a confidence level of 0.95 through the prop.test command in R. 252 individuals of 32 species distributed in 29 genera and 19 families were recorded. The Fabaceae family was the largest represented with seven species. Of the 32 species, 19 are native (59.37 %) and 13 introduced (40.63 %). Based upon their origin, 77.79 % of the individuals are native and 22.21 % introduced. Regarding their dimensions, the percentage differences are greater: the native ones represent 91.69 % of the basimetric area, 92.36 % of the crown area, 92.22 % of the assumed crown area and 96.78 % of crown volume, while the non-natives present values lower than 9.00 %. At the species level, those with the highest structural values were Prosopis laevigata followed by Vachellia farnesiana and Ebenopsis ebano. The three species are native belonging to the Fabaceae family and together they represent 44.05 % of the abundance and 63.71 % of the Urban Importance Value Index. According to the analysis of variance, the native species turned out to have higher values of richness, basal area, and crown area than the introduced species in the assessed localities.

Abstract We investigated whether racial discrimination accelerates the weight and Body Mass Index (BMI) gain in Blacks and Browns participants of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) in four years of follow-up. We compared body weight and BMI between the 1st (2008-2010) and 2nd visit (2012-2014) of 5,983 Blacks and Browns participants. Exposure to racial discrimination and covariates (age, sex, education, and research center) were obtained at the 1st visit. Linear mixed effects models stratified by race/skin color were used. Report of racial discrimination was more frequent among Blacks (32.1%) than Browns (6.3%). During the follow-up period, Blacks and Browns gained an average of 1.4kg and 1.2kg, respectively. This increase was greater among those who reported discrimination when compared to those who did not, both in Blacks (2.1kg vs.1.0kg, p < 0.001) and Browns (1.9kg vs. 1.1kg, p < 0.05). The results of the interaction between racial discrimination and time showed that Blacks, but not Browns, who reported racial discrimination had greater weight and BMI gains between visits. Our results suggest that reducing racial discrimination would contribute to prevent and/or control obesity increase in the country.

Resumo Investigou-se se a discriminação racial acelera o ganho de peso corporal e o Índice de Massa Corporal (IMC) em pretos e pardos participantes do Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil) em quatro anos de seguimento. Comparou-se o peso corporal e o IMC entre a 1ª (2008-2010) e a 2ª visita (2012-2014) de 5.983 participantes pretos e pardos. A exposição à discriminação racial e às covariáveis (idade, sexo, escolaridade e centro de pesquisa) foram obtidas na 1ª visita. Foram utilizados modelos lineares de efeitos mistos estratificados por raça/cor da pele. O relato de discriminação racial foi mais frequente entre pretos (32,1%) do que em pardos (6,3%). Durante o período de acompanhamento, pretos e pardos ganharam uma média de 1,4kg e 1,2kg, respectivamente. Esse aumento foi maior entre os que relataram discriminação, quando comparados aos que não relataram, tanto em pretos (2,1 kg vs. 1,0 kg, p < 0,001) quanto em pardos (1,9kg vs. 1,1kg, p < 0,05). Após ajustes, os pretos, mas não os pardos, que relataram discriminação racial apresentaram maiores ganhos de peso e IMC entre as visitas. Nossos resultados sugerem que a redução da discriminação racial pode contribuir para prevenir e/ou controlar o aumento da obesidade no país.

Abstract We investigated whether racial discrimination accelerates the weight and Body Mass Index (BMI) gain in Blacks and Browns participants of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) in four years of follow-up. We compared body weight and BMI between the 1st (2008-2010) and 2nd visit (2012-2014) of 5,983 Blacks and Browns participants. Exposure to racial discrimination and covariates (age, sex, education, and research center) were obtained at the 1st visit. Linear mixed effects models stratified by race/skin color were used. Report of racial discrimination was more frequent among Blacks (32.1%) than Browns (6.3%). During the follow-up period, Blacks and Browns gained an average of 1.4kg and 1.2kg, respectively. This increase was greater among those who reported discrimination when compared to those who did not, both in Blacks (2.1kg vs.1.0kg, p < 0.001) and Browns (1.9kg vs. 1.1kg, p < 0.05). The results of the interaction between racial discrimination and time showed that Blacks, but not Browns, who reported racial discrimination had greater weight and BMI gains between visits. Our results suggest that reducing racial discrimination would contribute to prevent and/or control obesity increase in the country.

Resumo Investigou-se se a discriminação racial acelera o ganho de peso corporal e o Índice de Massa Corporal (IMC) em pretos e pardos participantes do Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil) em quatro anos de seguimento. Comparou-se o peso corporal e o IMC entre a 1ª (2008-2010) e a 2ª visita (2012-2014) de 5.983 participantes pretos e pardos. A exposição à discriminação racial e às covariáveis (idade, sexo, escolaridade e centro de pesquisa) foram obtidas na 1ª visita. Foram utilizados modelos lineares de efeitos mistos estratificados por raça/cor da pele. O relato de discriminação racial foi mais frequente entre pretos (32,1%) do que em pardos (6,3%). Durante o período de acompanhamento, pretos e pardos ganharam uma média de 1,4kg e 1,2kg, respectivamente. Esse aumento foi maior entre os que relataram discriminação, quando comparados aos que não relataram, tanto em pretos (2,1 kg vs. 1,0 kg, p < 0,001) quanto em pardos (1,9kg vs. 1,1kg, p < 0,05). Após ajustes, os pretos, mas não os pardos, que relataram discriminação racial apresentaram maiores ganhos de peso e IMC entre as visitas. Nossos resultados sugerem que a redução da discriminação racial pode contribuir para prevenir e/ou controlar o aumento da obesidade no país.

Abstract In the cropping systems that integrate the corn crop, the insertion of Crotalaria ochroleuca G. Don is predominantly intercropped. In this context, there is a need to observe herbicides that present selectivity for this sunn hemp species. The objective of this study was to evaluate the selectivity of pre and post-emergent herbicides on C. ochroleuca. Two field experiments were conducted in randomized blocks with four replications, involving the pre-emergence and post-emergence application of different herbicide treatments. For the pre-emergent ones, amicarbazone, atrazine and flumioxazin provided phytotoxicity higher than 90% and, consequently, low plant biomass. On the other hand, acetochlor and s-metolachlor did not cause phytotoxicity and did not affect the dry mass of crotalaria. In post-emergence, atrazine + mesotrione showed phytotoxicity >95%, followed by nicosulfuron and 2.4-D with phytotoxicity between 50-60%, whereas tembotrione did not cause injury to the plants. Thus, it was found that among the pre-emergent, acetochlor and s-metolachlor were selective, and for the emerging powders, only tembotrione was the most selective for all parameters analyzed.

Resumo Nos sistemas de cultivo que integram a cultura do milho, a inserção de Crotalaria ochroleuca G. Don é predominantemente consorciada. Nesse contexto, há a necessidade de se observar herbicidas que apresentem seletividade para esta espécie de crotalária. O objetivo deste trabalho foi avaliar a seletividade de herbicidas pré e pós-emergentes sobre C. ochroleuca. Dois experimentos de campo foram conduzidos em blocos casualizados com quatro repetições, envolvendo a aplicação de diferentes tratamentos herbicidas em pré-emergência e pós-emergência. Para os pré-emergentes, amicarbazone, atrazina e flumioxazin proporcionaram fitotoxicidade superior a 90% e, consequentemente, baixa biomassa vegetal. Por outro lado, o acetocloro e o s-metolacloro não causaram fitotoxicidade e não afetaram a massa seca da crotalária. Em pós-emergência, atrazina + mesotrione apresentou fitotoxicidade >95%, seguido de nicosulfuron e 2,4-D com fitotoxicidade entre 50-60%, enquanto o tembrotrione não causou danos às plantas. Assim, verificou-se que entre os pré-emergentes, o acetocloro e o s-metolacloro foram seletivos, e para os pós emergentes, apenas o tembotrione foi o mais seletivo para todos os parâmetros analisados.

Resumen Introducción: en pacientes con enfermedades reumatológicas autoinmunes se recomienda la aplicación sistemática y secuencial de una serie de vacunas para la prevención de enfermedades transmisibles. El objetivo de este estudio fue estimar la proporción de pacientes con esclerosis sistémica (ES) que recibieron vacunación contra el coronavirus (SARS-CoV-2). Materiales y métodos: se envió una encuesta anónima por correo electrónico o contacto por WhatsApp desde mayo a septiembre de 2021, con preguntas para evaluar la adherencia al esquema de vacunación recomendado en pacientes con enfermedades reumatológicas, así como temores, preferencias y adherencia al esquema de vacunación contra el SARS-CoV-2. Resultados: se incluyeron 295 pacientes con ES. El 68,81% estaba vacunado contra el SARS-CoV-2 con al menos una dosis, de los cuales el 48,7% tenía dos dosis. El 84,75% refirió conversar con su médico sobre su esquema de vacunación general. Solo el 5,4% tenía las cuatro vacunas. El 93,56% manifestó voluntad de vacunarse contra el SARS-CoV-2; el 56,27% prefirió la vacuna Sputnik V. El 7,46% manifestó su voluntad de no vacunarse. Los factores que influyeron en la adherencia a la vacunación, con mayor frecuencia, fueron el miedo a contraer la infección por SARS-CoV-2 (86,1%) y las reacciones adversas (23,05%). Conclusiones: destacamos el hecho de que solo 6 meses después de que se dispusiera la vacunación contra el SARS-CoV-2, la mitad de los pacientes con ES tenía el esquema recomendado completo.

Abstract Introduction: in patients with autoimmune rheumatic diseases, the systematic and sequential application of a series of vaccines is recommended for the prevention of communicable diseases. The objective was to estimate the proportion of patients with systemic sclerosis (SSc) who received vaccination against coronavirus (SARS-CoV-2). Materials and methods: since may to september 2021, an anonymous survey was sent by email or messaging app, containing questions to assess adherence to the recommended vaccination schedule in patients with rheumatic diseases, as well as fears, preferences and adherence to vaccination schedule against SARS-CoV-2. Results: 295 patients with SSc were included. 68.81% were vaccinated for SARS-CoV-2 with at least one dose, 48.7% of this group had two doses. 84.75% reported talking to their doctor about their general vaccination schedule. Only 5.4% had all four vaccines. 93.56% expressed willingness to be vaccinated against SARS-CoV-2, 56.27% preferred the Sputnik V vaccine. 7.46% expressed their willingness to not be vaccinated. The factors that most frequently influenced adherence to vaccination were fear of contracting SARS-CoV-2 infection (86.1%) and adverse reactions (23.05%). Conclusions: we highlight the fact that only 6 months after vaccination against SARS-CoV-2 became available, half of the patients with SSc had the full recommended schedule.

ABSTRACT Feline viral leukemia (ViLeF) is a lethal retroviral disease with a high prevalence in Colombia that affects felines of different ages and sexes. The purpose of this investigation was to determine the frequency by serodiagnosis of ViLeF in felines of the integral center of animal welfare Ceiba, located in Rionegro, Antioquia (Colombia), during 2020. For that, a longitudinal descriptive study of ViLeF serofrequency from were made January to December 2020. 92 cats were sampled, which were tested for p27 by commercial Elisa immunoassay (Idexx©, Snap Combo Plus®, Maine, USA). The frequency of positive felines was 30/92 (32,60%). May was the month with the highest frequency (9,78%). The positivity frequency for males was 17/92 (18,47%) and the frequency for females 13/92 (14,13%). The main age of seropositivity was 2,14 years. The frequency of ViLeF in 2020 for Ceiba, Rionegro (Colombia) is 32,60%. This is a high value in comparison to descriptions in other shelters for felines. ViLeF, in Colombia, is a disease that has been reported with more frequency because prevention measures are not being adopted routinely.

RESUMEN La leucemia viral felina (ViLeF) es una enfermedad retroviral letal, de una elevada prevalência en Colombia, que afecta a felinos de diferentes edades y sexos. El objetivo de esta investigación fue determinar la frecuencia por serodiagnóstico de ViLeF en felinos del centro integral de bienestar animal Ceiba, ubicado en Rionegro, Antioquia (Colombia), en 2020. Para ello, se realizó un estudio descriptivo longitudinal de serofrecuencia de ViLeF desde enero hasta diciembre de 2020. Fueron muestreados 92 gatos, a los cuales se les efectuó una prueba p27 por inmunoensayo comercial Elisa (Idexx©, Snap Combo Plus®, Maine, EE. UU.). La frecuencia de felinos positivos fue 30/92 (32,60%) y el mes de mayo fue el de mayor frecuencia (9,78%). Los machos positivos fueron 17/92 (18,47%) y las hembras 13/92 (14,13%). La edad promedio de seropositividad fue 2,14 años. La frecuencia de ViLeF en 2020 para Ceiba, Rionegro (Colombia) es de 32,60%, un valor elevado con respecto a descripciones en otros albergues para felinos. ViLeF es una enfermedad que está siendo reportada con mayor frecuencia en Colombia, debido a que las medidas de prevención no se están adoptando rutinariamente.

Abstract: The aim of this study was to evaluate the design and implementation of the Information System for Cervical Cancer Detection Program in Women in the Institute for Social Security and Services for State Workers. We performed a retrospective study applying the framework and tools for Performance Routine Information System Management (PRISM). A sample of 38 subjects was interviewed in 13 health facilities. The information system’s evaluation showed an overall performance of 73.7% at the beginning of 2017. The improvement between versions was mainly observed in the quality of the data (64.6% vs 72.5%), while the use of the information was very similar (78.6% vs 78.9%). We concluded that this information system provides good information to follow-up and control of its beneficiary population. However, there is an opportunity to improve health staff training, also new indicators for health outcomes are required.

Abstract: Element of flexibility as well as controversial, assessments made by the EU Court of Justice regard-ing preliminary rulings referred to it constitute an expression of distinctive judicial independence. Such positions have led in some cases to a refusal to answer the doubts submitted from national administrative departments. Faced with such disturbing examples, this study proposes a scientific methodology for a better understanding, by taking into account one of the most recently produced, which precisely affects a Spanish administrative body.

Resumo: Elemento de flexibilidade e também polémico, as apreciações do Tribunal de Justiça da União Européia sobre as questões prejudiciais que lhe são submetidas são expressão de uma marcada independência judicial. Estas posições o levaram, em alguns casos, a recusar-se a responder às dúvidas enviadas pelas autoridades administrativas nacionais. Diante de exemplos tão preocupantes, este estudo propõe uma metodologia científica para melhor compreendê-los, focalizando-se especialmente em um dos (casos) mais recentes produzidos, e que afeta especificamente um órgão administrativo espanhol.

Resumen: Elemento de flexibilidad a la par que polémico, las apreciaciones pronunciadas por el Tribunal de Justicia de la UE en cuanto a las cuestiones prejudiciales que le son remitidas constituyen expresión de una acentuada independencia judicial. Estos posicionamientos le han llevado en algunos casos a rechazar contestar a las dudas remitidas desde instancias administrativas nacionales. Ante tan inquietantes ejemplos, este estudio propone una metodología científica para comprenderlos mejor, centrándose con carácter especial uno de los más recientemente producidos, y que afecta a precisamente un órgano administrativo español.

Abstract Background: Heliopsis longipes root is the widely used organ from the plant due to its culinary and medicinal importance. Nevertheless, during its collection the foliage is discarded. Therefore, it is required to perform studies about the phytochemical content with biological activity present in the different plant organs of the foliage, for a better exploitation of the plant. Hypothesis: The concentration of phenolic compounds with antioxidant activity varies according to the type of plant organ and the geographic location of the plant collection. Study species: Heliopsis longipes Site and years of study: The H. longipes plants were collected in three locations (Conca, San Juan Buenaventura and Beltran) from Sierra Gorda of Mexico, between 2017 and 2018. Methods: In this study, they were analyzed the methanolic extracts from H. longipes leaves and flowers, in order to determine the content of the phenolic compounds and scavenging of radicals activity (DPPH• and ABTS•+). Further characterization of the extracts was carried out by chromatography (UPLC). Results: The total content of polyphenols, flavonoids and condensed tannins varied in depending on the type of plant organ and the origin site of H. longipes, being the leaves of Beltran those that represent the best source of phenolic compounds with scavenging activity of the radicals DPPH• and ABTS•+. In the extracts, phenolic acids and flavonoids were identified. Conclusions: The geographical climatic conditions influence the phenolic content and antioxidant activity of the methanolic extracts from leaves and flowers of H. longipes.

Resumen Antecedentes: La raíz de Heliopsis longipes es el órgano de la planta que se usa ampliamente debido a su importancia culinaria y medicinal. Sin embargo, durante su colecta el follaje es desechado. Por lo tanto, se requiere realizar estudios acerca del contenido de fitoquímicos con actividad biológica presentes en los distintos órganos vegetales del follaje, para un mejor aprovechamiento de la planta. Hipótesis: La concentración de compuestos fenólicos con actividad antioxidante varía de acuerdo con el tipo de órgano vegetal y la ubicación geográfica de recolecta de la planta. Especies de estudio: Heliopsis longipes. Sitio y años de estudio: Las plantas de H. longipes se recolectaron en tres localidades (Concá, San Juan Buenaventura y Beltrán) de la Sierra Gorda de México, entre 2017 y 2018. Métodos: En este estudio, se analizaron los extractos metanólicos de hojas y flores de H. longipes para determinar el contenido de compuestos fenólicos y la actividad reductora de radicales (DPPH• y ABTS•+). Adicionalmente, la caracterización de los extractos se realizó mediante cromatografía (UPLC). Resultados: El contenido total de polifenoles, flavonoides y taninos condensados varió en función del tipo de órgano vegetal y sitio de origen de H. longipes, siendo las hojas de Beltrán las que representan la mejor fuente de compuestos fenólicos con actividad reductora de radicales DPPH• y ABTS•+. En los extractos, se identificaron ácidos fenólicos y flavonoides. Conclusiones: Las condiciones geográficas climáticas influyen en el contenido fenólico y actividad antioxidante de los extractos metanólicos de hojas y flores de H. longipes.

Abstract: The structure and diversity of woody species in a plant community with livestock history was evaluated, which was excluded a ten years in the RENAC Conservation and Research Area, municipality of Linares in the Northeast of Mexico. A total of 10 randomly distributed sampling plot from 100 m2 (10 x 10 m) were established. At the plots, arboreal and shrubby individuals with a basal diameter (d0.10) equal to or greater than 3 cm, corresponding to the original remaining vegetation were considered. To evaluate the regeneration (d0.10 < 3 cm) sites of 1 m2 (1 x 1 m) were established in each corner and the center of the site of 100 m2. The total height (h), basal diameter (d0.10) and cup cover (N-S, E-O) were measured. The ecologica parameters analyzed were abundance (Ar), dominance (Dr), frequency (Fr) and importance value index (IVI), also estimates of Shannon (H ’) and Margalef (Da) indices. 10 families, 12 genera and 14 species were registered. The family with the highest number of species (4) was Fabaceae. The species with the highest values of importance index (IVI) were Havardiapallens, Zanthoxylum fagara and Celtis laevigata, typical of species of mature plant communities of the Tamaulipan thornscrub and submontane thorn scrub. In the plant community studied, there is a richness and diversity of typical species of arid and semi-arid climate of northeastern Mexico, and both the pattern of diameter classes and the Jaccard similarity index suggest that an active dynamics of regeneration in the plant community.

Resumen: Se evaluó la estructura y diversidad de especies leñosas en una comunidad vegetal con historial pecuario que fue excluida hace una década dentro del Área de Conservación e Investigación RENAC, en el municipio de Linares (Noreste de México). Se establecieron 10 sitios de muestreo de 100 m2 (10 x 10 m) distribuidos aleatoriamente. En los sitios se consideraron los individuos arbóreos y arbustivos con un diámetro basal (d 0.10) igual o mayor a 3 cm, como correspondiente a la vegetación original remanente. Para evaluar la regeneración (d 0.10 < 3 cm) se establecieron sitios de 1 m 2 (1 x 1 m) en cada esquina y el centro del sitio de 100 m2. Se midió la altura total (h), diámetro basal (d0.10m) y cobertura de copa (N-S, E-O). Los parámetros ecológicos analizados fueron de abundancia (Ar), dominancia (Dr), frecuencia (Fr) e índice de valor de importancia (IVI), además estimaciones de índices de Shannon (H’) y Margalef (Da). Se registraron 10 familias, 12 géneros y 14 especies. La familia con mayor número de especies (4) fue Fabaceae. Las especies con mayores valores de índice de valor de importancia (IVI) fueron Havardia pallens, Zanthoxylum fagara y Celtis laevigata, especies típicas de comunidades vegetales maduras del matorral espinoso tamaulipeco y submontano. En la comunidad vegetal estudiada, se presentan una riqueza y diversidad de especies típicas de clima árido y semiárido del noreste de México y, tanto el patrón de clases diamétricas, como el índice de similitud de Jaccard sugieren una activa dinámica de la regeneración en la comunidad vegetal.

Abstract The objective of this study was to evaluate the substitution of corn grain (CG) for increasing levels of dehydrated lemon bagasse (DLB) in rearing heifer´s diets. Forty Braford heifers (158 ± 3.5 kg LW) were randomly assigned in 20 pens, considering each pen as an experimental unit. Four treatments were generated from the inclusion of increasing proportions of DLB in the diet (0, 15, 30, and 45% DM) in replacement of the corn grain. The experiment lasted 90 d. Final live weight (FLW), average daily gain (ADG), dry matter intake (DMI), feed conversion (feed:gain), backfat thickness (BFT), and rib eye area (REA) were evaluated. Individual samples of each ingredient and composite samples of the offered rations were collected for the determination of the chemical composition. The experimental design was completely randomized with 5 repetitions per treatment. The results were analyzed using the GLM procedure of SAS, being declared differences with P < 0.05. The partial or total substitution of the GM for the DLB did not generate significant differences on the FLW (P = 0.61), DMI (P = 0.59), ADG (P = 0.35), feed conversion (P = 0.29), REA (P = 0.19), and BFT (P = 0.17). It is concluded that DLB is a co-product that can partially or totally replace the corn grain in rearing diets without affecting animal performance.

Resumen El objetivo de este trabajo fue evaluar la sustitución del grano de maíz (GM) por niveles crecientes de bagazo de limón deshidratado (BLD) en dietas de recría de vaquillonas. Se utilizaron 40 vaquillonas Braford (158 ± 3,5 kg PV inicial) asignadas aleatoriamente en 20 corrales, siendo cada corral la unidad experimental. Se generaron cuatro tratamientos a partir de la inclusión de proporciones crecientes de BLD en la dieta (0, 15, 30 y 45 % MS) en reemplazo del GM. La duración del ensayo fue de 90 d. Se evaluó el peso vivo final (PVf), el aumento medio diario (AMD), el consumo de ración (CMS), la conversión alimenticia (EC), el espesor de grasa dorsal (EGD) y el área de ojo de bife (AOB). Se recolectaron muestras individuales de cada ingrediente y muestras compuestas de las raciones ofrecidas para la determinación de la composición química. El diseño experimental fue completamente aleatorizado con 5 repeticiones por tratamiento. Los resultados fueron analizados utilizando el procedimiento GLM de SAS, siendo declaradas diferencias con P < 0,05. La sustitución parcial o total del GM por el BLD no generó diferencias significativas sobre el PVf (P = 0,61), CMS (P = 0,59), AMD (P = 0,35), EC (P = 0,29), AOB (P = 0,19) y EGD (P = 0,17). Se concluye que el bagazo de limón es un sub-producto que puede sustituir en forma parcial o total al grano de maíz en dietas de recría sin afectar el desempeño animal.

Abstract: We estimate the impact of rural-urban migration from the period 2010-2015 on informality in metropolitan areas of Mexico. The estimation of ordinary least squares does not establish any effect, while the estimation with instrumental variables finds that exogenous rural urban migration increases informality. Other variables such as unemployment, labour participation and inequality are unaffected, indicating that informal sector allows to absorb changes in labour supply in the short term, albeit with possible negative effects on labour income of substitute workers.

Resumen: Se estima el impacto de la migración rural urbana del período 2010-2015 en la informalidad de las zonas metropolitanas de México. La estimación de mínimos cuadrados ordinarios no establece ningún efecto, mientras que la estimación con variables instrumentales encuentra que la migración rural urbana exógena incrementa la informalidad. Otras variables como el desempleo, la participación laboral y la desigualdad no son afectadas, lo que indica que el sector informal permite absorber las variaciones de la oferta laboral en el corto plazo, aunque con posibles efectos negativos sobre los ingresos laborales de los trabajadores sustitutos de los migrantes rurales.

RESUMEN Introducción. La avicultura moderna demanda el desarrollo de estrategias alimenticias que incrementen el nivel de sostenibilidad en las parvadas, lo cual ha generado interés por incluir ingredientes no tradicionales en las dietas para aves. Objetivo. Evaluar el efecto de la inclusión parcial de frijol caupí(Vigna unguiculata) y plátano (Musa spp.) sobre parámetros zootécnicos de pollos de engorde. Materiales y métodos. Se formuló una dieta isoprotéica (20% PC) e isocalórica (3,7 kcal ED/g) para alimentar durante 42 días 160 pollitos Cobb 500, con sustitución parcial de 0; 18; 20 y 22% el alimento concentrado (AC) por una mezcla experimental (ME) de V. unguiculata y Musa spp. Las aves fueron distribuidas al azar en 16 corrales según los tratamientos (T): T0: 100% AC; T1: 82% AC + 18% ME; T2: 80% AC + 20% ME y, T3: 78% AC + 22% ME y 4 repeticiones. Para evaluar la respuesta productiva, se consideraron los parámetros ganancia total de peso (GTP), ganancia diaria de peso (GDP), factor de conversión alimenticia (FCA), consumo (C), rendimiento en canal (RC) y mortalidad (M). Resultados. El tratamiento control (T0) registró la mayor GTP (2,461±0,02 g), GDP (58,60±0,03 g), C (4,247±3,20 g) y FCA (1,73±0,06); sin embargo, el análisis estadístico reveló que el T0 y T1 son estadísticamente iguales, mientras que T2 y T3 presentaron diferencia significativa (p<0,05) entre sí para la mayoría de variables y, frente a T0 y T1. En cuanto al RC, el T0 y T1 difirieron significativamente (p<0,05) con respecto a T2 y T3. Durante el experimento no murieron aves en ninguno de los tratamientos evaluados. Conclusión. Sustituir hasta un 18% el AC por una mezcla balanceada a base de V. unguiculatay Musaspp. en pollos de engorde, resulta una alternativa nutricional para la avicultura familiar.

ABSTRACT Introduction. The modern poultry demands the development of feeding strategies that increase the level of sustainability in flocks, which has generated interest in including non-traditional ingredients in poultry diets. Objective. To assess the effect of partial inclusion of cowpea bean (Vigna unguiculata) and banana (Musa spp.) on zootechnical parameters of broilers chicken. Materials and methods. An isoproteic diet (20% CP) and isocaloric (3.7 kcal ED/g) to feed 160 Cobb 500 chicks for 42 days, with partial replacement of 0; 18; 20 and 22% the concentrated food (CF) by aexperimental mixture (EM) of V. unguiculata and Musa spp. The birds were randomly distributed in 16 farmyards according to treatments (T): T0: 100% CF; T1: 82% CF + 18% EM; T2: 80% CF + 20% EM and T3: 78% FC + 22% EM and 4 repetitions. For evaluate the productive response the parameters weight gain (TWG), daily weight gain (DWG), feeding conversion factor (FCF), consumption (C), Carcass yield (CY) and mortality (M). Results. The control treatment (T0) recorded the highest TWG (2.461±0.02 g), DWG (58.60±0.03 g), C (4.247±3.20 g) and, FCF (1.73±0.06); however, statistical analysis revealed that T0 and T1 are statistically equal, while T2 and T3 showed significant differences (p<0.05) to each other for the majority of variables and, in front T0 and T1. As for CY, T0 and T1 differed significantly (p<0.05) with respect to T2 and T3. During the experiment, no birds died in any of the treatments evaluated. Conclusion. Replace up to 18% CF with a balanced mixture based on V. unguiculata and Musa spp. in broilers, it has proved to be a nutritional alternative for family poultry farming.

Abstract The Lagunera Region, located in the North-Center of Mexico, is the main dairy basin of the country in which 21 % of the national production is obtained. In the region there are 90 biodigesters, of which 10 use biogas to produce electricity and about 50 burn it with equipment called “Biogas Torch” with the ability to destroy methane. In the dairy stables in the region, the use of electrical resistors or liquefied petroleum gas (LPG) is used to heat the water used in sanitation, which generates an annual expenditure close to $Mx 300,000 ($1.30/kWh), when the process could be more economical and sustainable with the use of biogas. The objectives of this work were to design and validate the innovation of adding a coil to the torches, so that in addition to burning the biogas, as current torches do, heat is used to heat the water demanded in various processes of the dairy stables. The first phase of the methodology consisted of performing the calculation of the heat transfer process, which occurs within the new torch, with the incorporated coil, through which the water circulates, which once hot, will be used in several processes within of the stable. 30 experimental runs were carried out in which the parameters were measured: water temperature, time, pressure and biogas flow, as well as the CH4, CO2 and H2S values. The collected data were analyzed statistically (ANOVA of one factor), which demonstrated the consistency of the water heating process proposed in this work. This innovation can be used in dairy stables and pig farms where biogas is produced and hot water is required for its processes and in production units that require heating in regions with cold or low temperate climates.

Resumen La Comarca Lagunera, ubicada en el Norte-Centro de México, es la principal cuenca lechera del país en la cual se obtiene el 21 % de la producción nacional. En la región existen 90 biodigestores, de los cuales 10 emplean el biogás para producir electricidad y alrededor de 50 lo queman con un equipo denominado “Antorcha de Biogás” con capacidad para destruir el metano. En los establos lecheros de la región es común la utilización de resistencias eléctricas o bien gas licuado de petróleo (GLP) para calentar el agua utilizada en la sanitización, lo que genera un gasto anual cercano a los $300,000 (1.30 $/kWh) cuando el proceso podría ser más económico y sustentable con la utilización del biogás. El presente trabajo tuvo como objetivos diseñar y validar la innovación de agregar un serpentín a las antorchas, para que además de quemar el biogás, como lo hacen las antorchas actuales, se aproveche el calor para calentar el agua demandada en diversos procesos de los establos lecheros. La primera fase de la metodología consistió en realizar el cálculo del proceso de transferencia de calor, que ocurre dentro de la nueva antorcha, con el serpentín incorporado, a través del cual circula el agua que una vez caliente será utilizada en varios procesos dentro del establo. Se realizaron 30 corridas experimentales en las que se midieron los parámetros: temperatura del agua, tiempo, presión y flujo del biogás, así como los valores de CH4, CO2 y H2S. Los datos se analizaron estadísticamente (ANOVA de un factor) con lo que se demostró la consistencia del proceso de calentamiento del agua propuesto en este trabajo. Esta innovación puede ser utilizada en establos lecheros y granjas porcinas donde se produzca biogás y se requiera agua caliente para sus procesos y en unidades de producción que requieran calefacción en regiones con climas fríos o templados.