Abstract Plant growth-promoting bacteria (PGPB) that inhabit root rhizosphere of plants are of great agricultural importance due to their ability to produce phytohormones during root colonization. These phytohormones produce physiological changes in the plant that favor a greater absorption of nutrients, promote growth and increase production. This study analyzed the effect of inoculation of two of these bacteria, Azospirillum sp. and Pseudomonas fluorescens, under field conditions representative of the Andean Highlands. The experiment was carried out using flour corn seed of the INIAP-101 variety in a randomized complete block design with six repetitions. The treatments corresponded to: T1 (Azospirillum sp.), T2 (P. fluorescens), T3 (Azospirillum sp. and P. fluorescens), T4 (control, conventional chemical fertilization) and T5 (absolute control). The application of these bacteria significantly increased (p<0.05) the root length, the diameter of the cob, and the yield of fresh corn (“elotes” or “choclos”). The combined inoculation of these bacteria (T3) obtained the highest yield, with 19.70 t ha−1 of fresh corn; while the chemical control and the absolute control got 17.12 and 13.58 t ha−1 of fresh corn, respectively. The economic analysis of T3 reported a benefit/cost of 1.35, which indicates that the synergism of these two bacteria could be a sustainable strategy to improve yields and reduce the use of chemical fertilizers for corn production in the Andean region.

Resumen Las bacterias benéficas que habitan la rizósfera de las plantas son de gran interés agrícola debido a su capacidad para producir fitohormonas durante la colonización radicular. Estas fitohormonas producen cambios fisiológicos en la planta que favorecen una mayor absorción de nutrientes que provocan un rápido crecimiento vegetativo y una mayor producción. Esta investigación tuvo como objetivo evaluar el efecto de la inoculación de dos de estas bacterias, Azospirillum sp. y Pseudomonas fluorescens en el cultivo de maíz harinoso bajo condiciones de campo típicas de la región alto andina. El experimento se realizó utilizando semilla de maíz harinoso de la variedad INIAP-101 con un diseño de bloques completos al azar y seis repeticiones. Los tratamientos correspondieron a: T1 (Azospirillum sp.), T2 (P. fluorescens), T3 (Azospirillum sp. y P. fluorescens), T4 (testigo con fertilización química convencional) y T5 (testigo absoluto). La aplicación de estas bacterias incrementó de manera significativa (p<0,05) la longitud de raíz, el diámetro de la mazorca y el rendimiento del maíz tierno (elotes o choclos). La inoculación combinada de estas bacterias (T3) obtuvo el mayor rendimiento con 19,70 t ha−1 de choclos, mientras que el testigo químico y el testigo absoluto obtuvieron 17,12 y 13,58 t ha−1 de choclos, respectivamente. El análisis económico de T3 reportó un coste/beneficio de 1,35, lo cual indicó que el sinergismo de estos dos géneros podría ser una estrategia sostenible para mejorar los rendimientos y reducir el uso de fertilizantes químicos en el cultivo de maíz de la región Andina.

Abstract Objective: Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system. Diagnosis is based on the Mc-Donalds criteria, magnetic resonance imaging (MRI) studies, and the expanded disability status scale (EDSS) which assesses disease progression. These criteria do not include the recently described cortical lesions. The aim of the study was to describe the most frequent location and morphology of cortical lesions in patients with MS in Puebla, Mexico. Methods: A descriptive, retrospective, cross-sectional, and analytical study was conducted on patients with MS at a tertiary care hospital. Patients diagnosed with relapsing-remitting, secondary-progressive, and progressive-relapsing MS variants with cranial magnetic resonance imaging were included in the study. Age, sex, MS variant, EDSS score, cognitive impairment, annual relapse rate, morphology, location, and number of cortical lesions were evaluated. Descriptive statistics were used. To compare features between groups, the χ2 test was used, and for correlations, the Spearman's Correlation Coefficient was used. A p ≤ 0.05 was considered significant. Results: Twenty-five patients met the selection criteria. The most frequent location of cortical lesions was the parietal region 84%, and the second was the temporal region 16%. The most common morphology was juxtacortical at 64% and mixed at 36%. The most frequent variant of MS was relapsing-remitting, present in 92%, and 8% had the secondary progressive variant. In the EDSS scale, the scores most frequently observed were 0.0 and 3.5. Conclusions: The most frequent location of cortical lesions was in the parietal region, and the most common morphology was juxtacortical.

Resumen Objetivo: La esclerosis múltiple es una enfermedad desmielinizante inflamatoria crónica del sistema nervioso central. El diagnóstico se basa en los criterios de Mc-Donalds, los estudios de Resonancia Magnética y la Escala Expandida del Estado de Discapacidad (EDSS) que evalúa la progresión de la enfermedad. Estos criterios no incluyen las lesiones corticales descritas recientemente. Describir la localización y morfología más frecuente de lesiones corticales en pacientes con esclerosis múltiple en Puebla, México. Métodos: Se realizó un estudio descriptivo, retrospectivo, transversal y analítico en pacientes con esclerosis múltiple en un hospital de tercer nivel de atención. Se incluyeron pacientes con diagnóstico de Esclerosis Múltiple con variantes Remitente-Recurrente, Secundaria-Progresiva y Progresiva-Recurrente con resonancia magnética de cráneo. Se evaluó edad, sexo, variante de esclerosis múltiple, puntaje de EDSS, deterioro cognitivo, tasa de recaída anual, morfología, ubicación y numero de lesiones corticales. Se utilizó estadística descriptiva. Para comparar características entre grupos se utilizó χ2, para correlaciones se utilizó Coeficiente de Correlación de Spearman. Una p ≤ 0.05 se consideró significativa. Resultados: 25 pacientes cumplieron con criterios de selección. La localización más frecuente de lesiones corticales fue la región parietal 84% y la segunda temporal 16%. La morfología más frecuente fue la yuxtacortical en un 64%, y la mixta en 36%. La variante más frecuente de esclerosis múltiple fue Remitente-Recurrente presente en 92%, y 8% la variante Secundaria Progresiva. En la escala de EDDS la puntuación con mayor frecuencia fue 0.0 y 3.5. Conclusiones: La localización más frecuente de las lesiones corticales fue en región parietal y la morfología más frecuente la yuxtacortical.

ABSTRACT The peripherin gene (PRPH2) mutation is associated with photoreceptor cell dysfunction as well as in several inherited retinal dystrophies. The PRPH2 mutation c.582-1G>A is a rare variant reported in retinitis pigmentosa and pattern dystrophy. Here Case 1 was of a 54-year-old woman with bilateral atrophy of the perifoveal retinal pigmentary epithelium and choriocapillaris with central foveolar respect. Autofluorescence and fluorescein angiography revealed perifoveal atrophy of the retinal pigmentary epithelium with an annular window effect without the “dark choroid” sign. Case 2 (mother of Case 1) presented with extensive atrophy of the retinal pigmentary epithelium and choriocapillaris. PRPH2 was evaluated and the c.582-1G>A mutation was identified in heterozygosity. An advanced adult-onset benign concentric annular macular dystrophy diagnosis was thereby proposed. The c.582-1G>A mutation is poorly known and not present in all common genomic databases. This case report is the first one to report a c.582-1G>A mutation associated with benign concentric annular macular dystrophy.

RESUMO Mutações do gene da periferina (PRPH2) estão associadas à disfunção das células fotorreceptoras e estão envolvidas em várias distrofias retinianas hereditárias. A mutação c.582-1G>A do gene PRPH2 é uma variante rara, relatada na retinite pigmentosa e nas distrofias em padrão. O caso 1 foi de uma mulher de 54 anos com atrofia bilateral do epitélio pigmentar da retina perifoveal e da coriocapilar, com acometimento foveolar central. A autofluorescência e a angiofluoresceinografia revelaram atrofia perifoveal do epitélio pigmentar da retina, com efeito de janela anular, sem o sinal da “coroide escura”. O caso 2 (mãe) apresentava extensa atrofia do epitélio pigmentar da retina e da coriocapilar. Foi feito um estudo do gene PRPH2, que identificou a mutação c.582-1G>A em heterozigose. Foi proposto um diagnóstico de distrofia macular anular concêntrica benigna de início adulto em estágio avançado. A mutação c.582-1G>A é pouco conhecida e não está presente em todos os bancos de dados genômicos usuais. Este é o primeiro relato de caso publicado de uma mutação c.582-1G>A associada à distrofia macular anular concêntrica benigna.

Abstract Objective: In this study, a comparative evaluation of the physicochemical properties of Cention N and other direct restorative materials was performed. Three restorative materials—a resin-modified glass ionomer (Fuji II LC), an alkasite-based resinous material (Cention N), and a resin composite (Tetric N Ceram)—were characterized in terms of degree of conversion, Knoop hardness number (KHN) ratio, flexural strength, elastic modulus, water sorption, water solubility, microshear bond strength to dentin, immediate microleakage, and radiopacity. Methodology: The microshear bond strength to dentin and microleakage of Cention N were evaluated with and without the application of an adhesive system (Tetric N Bond Universal). A one-way ANOVA test was used to analyze the data in terms of degree of conversion, KHN ratio, water sorption, water solubility, microshear bond strength to dentin, and radiopacity. A two-way ANOVA test (carried out considering the material type and ethanol aging as factors) was used to analyze the data in terms of flexural strength and elastic modulus. The Kruskal–Wallis test was used to statistically analyze the data on microleakage. A significance level of α=0.05 was used for all tests. Results: Fuji II LC was found to have the highest degree of conversion, water sorption, and microleakage, as well as the lowest flexural strength. Cention N had the highest solubility; when used with an adhesive system, it achieved bond strength and microleakage similar to those of the Tetric N Ceram composite. Tetric N Ceram had the highest degree of conversion, KHN ratio, and radiopacity. Conclusion: The properties of Cention N validate its efficacy as an alternative direct restorative material when used in conjunction with an adhesive system.

Resumen: Antecedentes: la Escala de Autoabsorción (SAS) es uno de los pocos instrumentos que mide la atención autofocalizada disfuncional o autoabsorción, un factor transdiagnóstico de vulnerabilidad a diversos trastornos emocionales. La estructura interna de la versión española de la SAS y su relación con otras variables no han sido examinadas, ni tampoco si sus subescalas aportan información relevante. Estos fueron los objetivos del presente estudio. Método: se analizó la estructura factorial de la SAS, su consistencia interna y la relación con la sintomatología depresiva y de estrés postraumático en una muestra comunitaria española de 519 adultos. Resultados: la SAS presentó una estructura bifactor simétrica con un factor general de autoabsorción que explicaba la mayoría de la varianza de los ítems y dos factores específicos de autoabsorción privada y pública. La escala total y las dos subescalas mostraron coeficientes de fiabilidad excelentes, buenos o adecuados (alfas/omegas = .70 - .88) y correlacionaban con la depresión y el estrés postraumático (r = .34 - .46). Conclusiones: la SAS proporciona medidas fiables y válidas de la atención autofocalizada disfuncional en adultos españoles, pero sus subescalas de autoabsorción privada y pública pueden no ser muy útiles más allá de la información proporcionada por su escala total.

Abstract: Background: The Self-Absorption Scale (SAS) is one of the few instruments that measure dysfunctional self-focused attention or self-absorption, a transdiagnostic factor of vulnerability to various emotional disorders. The internal structure of the Spanish version of the SAS and its relationship with other variables have not been examined, nor has whether its subscales provide relevant information. These were the two goals of the present study. Method: The factor structure of the SAS, its internal consistency, and its relationship with depression and post-traumatic stress were analyzed in a Spanish community sample of 519 adults. Results: The SAS presented a symmetrical bifactor structure with a general factor of self-absorption that explained most of the variance in the items and two specific factors of private and public self-absorption. The total scale and the two subscales of the SAS exhibited excellent, good or adequate reliability coefficients (alphas/omegas = .70 - .88) and correlated with depression and post-traumatic stress (r = .34 - .46). Conclusions: The SAS provides reliable, valid measures of dysfunctional self-focused attention in Spanish adults, but its Private and Public Self-absorption subscales are not much more useful than the information provided by its total scale.

ABSTRACT Introduction: Critically ill pediatric patients are susceptible to cerebral blood flow alterations that imply a deterioration of their functional health status. Objective: To identify predictors of a higher risk of poor functional outcome in critically ill pediatric patients with sepsis. Methods: A retrospective cohort study was conducted with children under 18 years of age with sepsis, who were admitted to the pediatric intensive care unit. Epidemiological, clinical, and functional health status variables were collected prior to admission, discharge, and after 6 months. Functional health status was assessed using the Pediatric Global State and Brain Status Category Scale. The change in performance status between admission and 6 months after discharge was assessed. A univariate analysis was performed to compare groups considering poor prognosis and change in functional status and their relationship with the variables. Results: A total of 46 patients were included. At 6 months after discharge, four (8.7%) had a poor functional prognosis and eight (17.4%) had functional worsening at admission. No associations were found between the predictor variables and morbidity, although some trends were observed in some variables, such as greater inotropic support (SIV > 20: 12.5% vs. 50%, p = 0.075), extracorporeal and renal replacement (25% vs. 2.6%, p = 0.074), and longer hospital stay (50% vs. 15.8%, p = 0.055). Conclusions: Support in the pediatric intensive care unit was not a predictor of functional morbidity in the sample.

RESUMEN Introducción: Los pacientes críticos pediátricos son susceptibles de presentar alteraciones del flujo sanguíneo cerebral que impliquen un deterioro de su estado de salud funcional. Objetivo: Identificar factores predictores de mayor riesgo de mala evolución funcional en pacientes pediátricos críticos con sepsis. Métodos: Se realizó un estudio de cohortes retrospectivo con menores de 18 años de edad con sepsis, ingresados en la unidad de cuidados intensivos pediátricos. Se recogieron variables epidemiológicas, clínicas y del estado de salud funcional previas al ingreso, al alta y a los 6 meses. El estado de salud funcional se evaluó mediante la escala de categorías de estado global y cerebral pediátrico. Se evaluó el cambio del estado funcional entre el ingreso y a los 6 meses del alta. Se realizó un análisis univariante para comparar grupos considerando el mal pronóstico y el cambio del estado funcional y su relación con las variables. Resultados: Se incluyeron 46 pacientes. A los 6 meses del alta, cuatro (8,7 %) presentaron mal pronóstico funcional y ocho (17,4 %) empeoramiento funcional respecto al ingreso. No se encontraron asociaciones entre las variables predictoras y la morbilidad, aunque se observó cierta tendencia en algunas como mayor soporte inotrópico (VIS > 20: 12,5 % vs. 50 %, p= 0,075), extracorpóreo y de reemplazo renal (25 % vs. 2,6 %, p= 0,074) y estancia hospitalaria más prolongada (50 % vs. 15,8 %, p= 0,055). Conclusiones: El soporte en la unidad de cuidados intensivos pediátricos no fue un predictor de morbilidad funcional en la muestra.

RESUMEN Introducción: la Medicina Nuclear es una especialidad médica que trata o diagnostica diferentes afecciones mediante imágenes de tipo funcional-molecular, a partir del empleo de fuentes no selladas. Un aspecto importante en el desempeño profesional es la adecuada gestión de sustancias que puedan resultar nocivas. Objetivo: fundamentar la estructura conceptual de la competencia gestión de desechos radiactivos. Métodos: se realizó una revisión bibliográfica con un análisis crítico reflexivo, se consideraron documentos normativos de la actividad en Medicina Nuclear, tesis, artículos y libros, publicados a partir del 2018 en español e inglés. La búsqueda fue realizada en las bases de datos SciELO durante el periodo comprendido de enero a mayo del 2023. Las palabras clave utilizadas fueron: competencias, gestión y desechos radiactivos. Fueron revisados 73 textos y se seleccionaron 20 para conformar el texto final. Resultados: se delimitaron cuatro núcleos temáticos: pertinencia de formar competencias profesionales, base teórico-metodológica, base legal y riesgos e implicaciones. Resulta evidente el insuficiente tratamiento teórico-metodológico a la gestión de desechos como actividad de los tecnólogos de Medicina Nuclear. Se propone la definición de la competencia, los problemas contextuales que aborda, ejes procesuales, criterio de desempeño y evidencias requeridas. Conclusiones: el estudio de las competencias profesionales en los tecnólogos de la salud es un campo de notable vigencia encaminado a desarrollar su profesionalización. La evidente relación establecida entre la competencia gestión de desechos radiactivos y la reducción de riesgos y accidentes, conlleva la responsabilidad de formar profesionales preparados para desempeñarse con éxito en la Medicina Nuclear.

ABSTRACT Introduction: Nuclear Medicine is a medical specialty that treats or diagnoses different conditions through functional-molecular images, using unsealed sources. An important aspect in professional performance is the proper management of substances that may be harmful. Objective: to support the conceptual structure of the radioactive waste management competence. Methods: a bibliographic review was carried out with a reflective critical analysis, normative documents of the activity in Nuclear Medicine, theses, articles, and books, published since 2018 in Spanish and English, were considered. The search was carried out in the SciELO databases from January to May 2023. The keywords used were competencies, management and radioactive waste. 73 texts were reviewed and 20 were selected to make up the final text. Results: four topic cores were defined: relevance of training professional competencies, theoretical-methodological base, legal base and risks and implications. The insufficient theoretical-methodological treatment of waste management as an activity of Nuclear Medicine technologists is evident. The definition of the competence, the contextual problems it addresses, procedural axes, performance criteria and required evidence are proposed. Conclusions: the study of professional competencies in health technologists is a field of notable validity aimed at developing their professionalization. The evident relationship established between radioactive waste management competence and the reduction of risks and accidents entails the responsibility of training professionals prepared to perform successfully in Nuclear Medicine.

ABSTRACT: The effect of different feed substrates incubated in filter bags [no bag (NB); Ankom® F57, 25 μm pore size (25AN); polyester, 45 μm pore size (45PB); polyester, 67 μm pore size (67PB) ] or dispersed in the medium on gas production, digestion and rumen fermentation was evaluated using an in vitro gas production system. Filter bags reduced (P < 0.01) gas production but increased (P < 0.01) the in vitro dry matter digestibility (45PB and 67PB). Additionally, the use of filter bags with smaller pore size, reduced total volatile fatty acid (P < 0.01), but had minimal effects on acetate, propionate, and butyrate concentration. Our research suggested that using filter bags with a pore size of 67 µ would reduce some negative effects of incubating feed substrate dispersed in the medium or in filter bags with smaller pore size. However, the use of bags with a larger pore size might allow the wash out of small feed particles with consequent overestimation of digestibility.

RESUMO: O efeito de diferentes substratos alimentares incubados em sacos de filtro [sem saco (NB); Ankom® F57, tamanho de poro de 25 μm (25AN); poliéster, tamanho de poro de 45 μm (45PB); poliéster, tamanho de poro de 67 μm (67PB) ] ou disperso no meio na produção de gás, digestão e fermentação ruminal foi avaliada usando um sistema de produção de gás in vitro. As bolsas de filtro reduziram (P < 0,01) a produção de gases, mas aumentaram (P < 0,01) a digestibilidade da matéria seca in vitro (45PB e 67PB). Adicionalmente, o uso de bolsas de filtro com tamanho de poro menor reduziu o ácido graxo volátil total (P < 0,01), mas teve efeitos mínimos na concentração de acetato, propionato e butirato. Nosso trabalho sugere que usar sacos de filtro com tamanho de poro de 67 µ reduziria alguns efeitos negativos da incubação de substrato de alimentação disperso no meio ou em sacos de filtro com tamanho de poro menor. No entanto, o uso de sacolas com poros maiores pode permitir a eliminação de pequenas partículas de ração com consequente superestimação da digestibilidade.

ABSTRACT A 51-year-old non-obese woman presented with a one-week history of progressive blurry vision within the inferior visual field of her left eye. Her only relevant past medical history was long-standing hypothyroidism and recent vaccination against Coronavirus Disease 2019 (COVID-19) with an mRNA vaccine 12 days before the onset of symptoms. At examination, the anterior segment was unremarkable, but the retinal fundus revealed a central retinal vein occlusion associated with a branch retinal artery occlusion of the superior temporal branch in her left eye. Ancillary tests to rule out thrombophilia, hyperviscosity, hypercoagulability, or inflammation were negative. Ultrasound tests were also negative for a cardiac or carotid origin of the branch retinal artery occlusion. At two-month follow-up, no new retinal vascular occlusive events were observed. Although the best-corrected visual acuity at presentation was 8/10 in the left eye, the final best-corrected visual acuity remained 3/10.

RESUMO Uma mulher de 51 anos, não obesa, apresentou história de uma semana de visão embaçada progressiva no campo visual inferior do olho esquerdo. Seu único histórico médico anterior relevante era hipotireoidismo de longa data e uma recente vacinação contra a Doença de Coronavírus 2019 (COVID-19), com vacina de mRNA, 12 dias antes do início dos sintomas. O exame mostrou segmento anterior normal, mas o fundo da retina revelou uma oclusão da veia central da retina associada a uma oclusão de ramo arterial da retina do ramo temporal superior no olho esquerdo. Testes auxiliares para descartar trombofilia, hiperviscosidade, hipercoagulabilidade ou inflamação apresentaram resultados negativos. Testes de ultrassom também foram negativos quanto a uma origem cardíaca ou da carótida da oclusão do ramo da artéria da retina. Após dois meses de acompanhamento, nenhum novo evento vascular oclusivo retiniano foi observado. Embora, a acuidade visual melhor corrigida na apresentação tenha sido de 8/10 no olho esquerdo, a acuidade visual final melhor corrigida permaneceu em 3/10.

Abstract This study examines the TV series Vis a Vis through the operationalization of the concept of anger competence (Chemaly 2018), which refers to the subject’s ability to express anger. But we put it into dialogue with Lorde’s (1981) consideration of anger as “productive” only when it transforms conditions of violence and/or injustice. In that sense, we contend that the narrative approach of the series does not reproduce the usual stigmatization of women's rage but rather legitimizes its expression as a response to misogyny, and exposes the practices and structures of subjecti(ficati)on from an intersectional perspective. To demonstrate this, we analyze how the enraged subject is constructed through the axes of class and race, what the mediatization of anger reveals, and its effects.

Resumo Este estudo examina a série Vis a Vis a partir da operacionalização do conceito de anger competence (Chemaly 2018), que se refere à capacidade dos sujeitos de expressar raiva, colocando-o em diálogo com Lorde (1981), que a considera “produtiva” apenas quando transforma condições de violência e/ou injustiça. Nesse sentido, argumentamos que a série não reproduz a estigmatização habitual da raiva feminina, mas legitima a sua expressão como resposta à misoginia e revela as práticas e estruturas de su(b)je(t)i(va)ção a partir de uma perspectiva interseccional. Para o demonstrar, abordamos o modo como o sujeito enfurecido é construído através dos eixos de classe e raça, o que a mediatização da raiva revela e os seus efeitos.

Resumen Este estudio examina la serie Vis a Vis a partir de la operacionalización del concepto de anger competence (Chemaly 2018), que remite a la capacitación de los sujetos para expresar la rabia. Pero la ponemos en diálogo con Lorde (1981), quien la considera “productiva” solo cuando transforma condiciones de violencia y/o injusticia. En ese sentido, sostenemos que la serie no reproduce la habitual estigmatización de la ira femenina, sino que legitima su expresión como respuesta a la misoginia y desvela las prácticas y estructuras de su(b)je(tiva)ción desde una perspectiva interseccional. Para demostrarlo, abordamos cómo se construye el sujeto enfurecido a través de los ejes de clase y raza, lo que la mediatización de la rabia revela y los efectos de esta.

Summary: The floodplain of the San Pedro River, a fluvial-delta formation, is one of the coastal areas affected by marine intrusion during the last glaciation. In this region, agriculture is the main economic activity; however, intensive agricultural practices, the geological past, current interactions with the marine system and the transport of salts through sediments and water make this area susceptible to soil salinization. To characterize the salinity of the agricultural area of the San Pedro River floodplain, two soil samplings were carried out at 91 sites over a period of two years. Samples were taken from depths of 0.0 to 0.3 m and from 0.0 to 0.1 m to depths of 1 m and 3 m. Fifty groundwater samples were collected. Saturation extracts were obtained (1: θsat) from the soil samples. For the soil and groundwater extracts, the pH, EC, and major cations and anions were determined, the sodium adsorption ratio was calculated in the original and adjusted formulations (SAR or and SAR adj ), and the exchangeable sodium percentage (ESP) was ascertained. The pH, EC and SAR or of the groundwater ranged from 6.94 to 8.37, 199 to 4660 µS cm-1 and 0.16 to 32.30 (mmolc L-1)1/2, while in the saturation extracts, the pH, EC and SAR or ranged from 4.81 to 8.58, 0.08 to 72.4 dS m-1 and 0.11 to 33.09 (mmolc L-1)1/2, respectively. The salinity problems in the study area are closely related to the intrusion of salts from the marine system.

Resumen: La planicie del río San Pedro, que tiene una formación fluvio-deltaica, es una de las superficies costeras que fueron afectadas por la intrusión marina durante la última glaciación. En esta zona, la agricultura es la principal actividad económica, sin embargo, las actividades agrícolas intensivas, su pasado geo-morfológico, la actual interdependencia con el sistema marino y el transporte de sales a través de los sedimentos y aguas, hacen que esta región sea susceptible a la acumulación de sales en los suelos. Con el objetivo de caracterizar la salinidad de la superficie agrícola de la planicie del río San Pedro, se hicieron dos muestreos de suelos en 91 sitios en un periodo de dos años. Se tomaron muestras de 0.0 a 0.3 m y de 0.0 a cada 0.1 m hasta profundidades de 1 m y 3 m. Se recolectaron 50 muestras de agua freática, además se obtuvieron extractos de saturación (1: θsat) de las distintas muestras de suelos. A los extractos de suelo y aguas freáticas, se les determinó el pH, CE, cationes y aniones mayoritarios, se calculó el parámetro relación de adsorción de sodio en su formulación original y ajustada (RAS or , RAS aj ) y el porciento de sodio intercambiable (PSI). El pH, CE y RAS or del agua freática estuvieron dentro de los intervalos de 6.94-8.37, 199-4660 µS cm-1 y 0.16-32.30 (mmolc L-1)1/2, mientras que en los extractos de saturación entre 4.81-8.58, 0.08-72.4 dS m-1 y 0.11-33.09 (mmolc L-1)1/2 respectivamente. Los problemas de salinidad en la zona de estudio están estrechamente relacionados con la intrusión de sales provenientes del sistema marino.

Summary: Cocoa is a traditional crop in southern Mexico, although its productivity is low due to edaphic and nutritional limitations. Hence, the aim of our research was to diagnose edaphic fertility and the nutritional content of cacao plantations in the main groups of cultivated soils in La Chontalpa, the main cocoa production area of Tabasco state, to identify the edaphic and nutritional variables that restrict crop productivity. Through the analysis of satellite images, sampling sites were selected in representative soils of the study area and the coordinates were geopositioned to locate them. Soil profiles were described to classify the soils of the sampling sites. Soil samples were collected at depths of 0-10, 10-30 and 30-50 cm, to determine variables of soil fertility. In producer trees, foliar samples were collected to determine the concentrations of macronutrients. The results indicate that the plantations are cultivated on Vertisols, Cambisols and Fluvisols, which do not show restrictions in most of the edaphic properties. However, due to the low C/N ratio (< 12) of the soils, there is a decrease in the OM and N contents, which are added to a K deficit, causing low concentrations of both macronutrients in the foliage of the plants. In conclusion, the main edaphic restrictions that can affect cocoa cultivation in La Chontalpa are the rapid loss of OM and a deficit of N and K in the soil, which cause low concentrations of both nutrients in the foliage of the trees.

Resumen: El cacao es un cultivo tradicional en el sur de México, que exhibe baja productividad debido a limitantes edáficas y de nutrición, por lo que el objetivo de la investigación fue diagnosticar la fertilidad edáfica y contenido nutrimental de las plantaciones de cacao, en los principales grupos de suelos cultivados en la Chontalpa, principal zona productora de Tabasco, para identificar las variables del suelo y nutrimentales que restringen la productividad del cultivo. Mediante análisis de imágenes satelitales, se seleccionaron sitios de muestreos en suelos representativos del área de estudio y se geoposicionaron las coordenadas para ubicarlos. Se describieron perfiles de suelos para clasificar los suelos de los sitios de estudio, y se colectaron muestras de suelos a las profundidades de 0-10, 10-30 y 30-50 cm, para determinar variables indicadoras de la fertilidad del suelo. En árboles productores se colectaron muestras foliares para determinar las concentraciones de macronutrientes. Los resultados indican que las plantaciones se cultivan sobre Vertisols, Cambisols y Fluvisols, que no presentan restricciones en la mayoría de las propiedades edáficas. Sin embargo, debido a la baja relación C/N (< 12) de los suelos, hay una disminución en los contenidos de MO y N, que se suman a un déficit de K, que provocan bajas concentraciones de ambos macronutrientes en el follaje de las plantas. Se concluye que las principales restricciones edáficas que pueden afectar al cultivo del cacao en la Chontalpa son la rápida pérdida de MO y déficit de N y K en el suelo, que provocan bajas concentraciones de ambos nutrientes en el follaje de los árboles.

Summary: Pecan tree is one of the most important crops in the Comarca Lagunera. Zinc (Zn) deficiency is one of the main problems that limit its productivity. Nanotechnology includes nutrimental materials, which may substitute conventional fertilizers with diverse ef fects on yield, and biophysical and nutraceutical quality in fruits. The ef fects of foliar application of ZnO nanoparticles on pecan trees (Western variety) were evaluated through the following treatments: control, 4000 (ZnSO4), 2000 (nps ZnO), 4000 (nps ZnO) mg L-1. The experimental design was randomized blocks with four replications. Variables evaluated in fruit and tree were the following: yield, number of nuts kg-1, length and width of the nut, concentration of Zn in leaflets, fatty acids, crude protein, percentage of fat and moisture. A significant dif ference was observed in yield and Zn level in the leaflets, where the best treatment was 4000 mg L-1 of ZnO nanoparticles, while for length of fruit a significant dif ference was observed, being the 4000 mg L-1 of ZnSO4 treatment the lowest value. About nutraceutical variables, the content of fatty acids evaluated by the content of saturated fats (C16:0 and C18:0) showed highly significant changes, being the treatment with the dose of 4000 mg L-1 of nanoparticles the one with the highest percentage. Unsaturated fatty acids (C18:1 and C18:3) showed significant dif ferences, where the treatments evaluated with nanoparticles were the ones with a lower percentage. Protein content also showed highly significant dif ferences, being the control treatment and the chemical based on ZnSO4 the higher treatments. Nanoparticles can be used to improve yield and supply Zn content to the crop, but fruit quality is af fected from a nutritional point of view.

Resumen: El nogal pecanero (Carya illinoinensis) es uno de los cultivos más importantes de la Comarca Lagunera. La deficiencia de zinc (Zn) es uno de los principales problemas que limitan su productividad. La nanotecnología incluye materiales nutrimentales con los que se pueden sustituir fertilizantes convencionales con variado efecto en rendimiento, calidad biofísica y nutracéutica en el fruto. Los efectos de la aplicación foliar de nanopartículas de ZnO en nogal pecanero variedad Western fueron evaluados mediante dosis de Zn con los siguientes tratamientos: control, 4000 (ZnSO4), 2000 (nps ZnO), y 4000 (nps ZnO) mg L-1. El diseño experimental fue en bloques al azar con cuatro repeticiones. Las variables evaluadas en fruto y árbol fueron: rendimiento, número de nueces kg-1, largo y ancho de nuez, concentración de Zn en foliolos, ácidos grasos, proteína cruda, porcentaje de grasa y humedad. Se observó diferencia significativa en rendimiento y nivel de Zn en los foliolos, donde el mejor tratamiento fue 4000 mg L-1 de nanopartículas de ZnO, mientras que para la variable largo de nuez se observó diferencia significativa, siendo inferior el tratamiento de 4000 mg L-1 de ZnSO4. En las variables nutracéuticas, el contenido de ácidos grasos evaluado mediante el contenido de grasas saturadas (C16:0 y C18:0) mostró cambios altamente significativos, siendo el tratamiento con la dosis de 4000 mg L-1 de nanopartículas el que tuvo mayor porcentaje. Los ácidos grasos insaturados (C18:1 y C18:3) mostraron diferencias significativas, siendo los tratamientos evaluados con nanopartículas los que tuvieron un porcentaje inferior. El contenido de proteína también mostró diferencias altamente significativas, siendo el tratamiento control y el químico a base de ZnSO4 los tratamientos superiores. Las nanopartículas pueden ser usadas para mejorar el rendimiento y abastecer el contenido de Zn al cultivo, pero la calidad de fruto se ve afectada desde el punto de vista nutricional.

Resumen: Este artículo tiene por objetivo comprender cómo el espacio y las posiciones de privilegio y opresión en torno a categorías sociales como la edad, clase, género y sexualidad influyen en la configuración de violencias entre personas gais, lesbianas, transgénero y transexuales. Se trata de una investigación cualitativa que utilizó el método biográfico y las trayectorias de vida. Algunos hallazgos señalan que los espacios de interacción influyen en las relaciones de violencia al ubicar a las personas, con identidades sexogenéricas disidentes, en relaciones de privilegio y opresión.

Abstract: This article aims to understand how the space and positions of privilege and oppression around social categories such as age, class, gender, and sexuality influence the configuration of violence between gays, lesbians, transgender and transsexual people. This is qualitative research that used the biographical method and life trajectories. Some findings indicate that interaction spaces influence relationships of violence by placing people with gender dissident gender identities in relationships of privilege and oppression.