Los biosólidos de aguas residuales urbanas en el contenido de metales pesados en un suelo cultivado de tomate (Lycopersicon esculentum Mill).

Con el objetivo de evaluar el impacto de la aplicación de biosólidos de aguas residuales urbanas en la concentración de metales pesados (MP) en el sistema suelo-planta y la composición microbiológica del suelo, se realizó el presente trabajo en el Instituto Nacional de Ciencias Agrícolas (INCA), La Habana, Cuba. La aplicación de biosólidos en el suelo Ferralítico Rojo compactado incrementó el contenido cobre (Cu), níquel (Ni) y cinc (Zn) en los sustratos; mientras que, el contenido de hierro (Fe) y manganeso (Mn) disminuyó, comportamiento que mantuvo la misma tendencia al evaluar los diferentes órganos de las plantas. Se destaca que las concentraciones de MP encontradas en los sustratos y los órganos vegetales no representaron riesgos de fitotoxicidad ya que fueron inferiores a los niveles considerados como máximos permisibles para este tipo de suelo y para las plantas de tomate

Age Appropriate Wisdom? Ethnobiological Knowledge Ontogeny in Pastoralist Mexican Choyeros

We investigate whether age profiles of ethnobiological knowledge development are consistent with predictions derived from life history theory about the timing of productivity and reproduction. Life history models predict complementary knowledge profiles developing across the lifespan for women and men as they experience changes in embodied capital and the needs of dependent offspring. We evaluate these predictions using an ethnobiological knowledge assessment tool developed for an off-grid pastoralist population, known as Choyeros, from Baja California Sur, Mexico. Our results indicate that while individuals acquire knowledge of most dangerous items and edible resources by early adulthood, knowledge of plants and animals relevant to the age and sex divided labor domains and ecologies (e.g., women’s house gardens, men’s herding activities in the wilderness) continues to develop into middle adulthood but to different degrees and at different rates for men and women. As the demands of offspring accumulate for parents with age, reproductive aged adults continue to develop their knowledge to meet their children’s needs. After controlling for vision, post-reproductive adults’ show the greatest ethnobiological knowledge. These findings extend our understanding of the evolved human life history by illustrating how changes in embodied capital and the needs of dependent offspring predict the development of men’s and women’s ethnobiological knowledge across the lifespan

Framework de gestión del conocimiento (FGC) basado en capas

Research in the eld of Knowledge Management (KM) has grown in accumulation and importance in both the academic and business worlds. However, it has not properly established how and when a KM initiative should be implemented. For the above, this paper describes the layers that conform the structure of a KMF that enables management of knowledge resources among members of an organization. From the KMF a prototype of Knowledge Management System (KMS) is presented oriented to the management of the knowledge of research groups.La investigación en el campo de la Gestion del Conocimiento (GC) ha crecido en acumuladoe importancia tanto en el mundo académico como empresarial. Sin embargo, no ha establecido apropiadamente cómo y cúando una iniciativa de GC debe ser aplicada. Por lo anterior, en el presente artículo se describe la estructura -basada en capas- de un framework de gestión del conocimiento (FGC) que permite la administración de los recursos de conocimiento articulando, por niveles, diferentes funciones y actividades para la administración de los recursos de conocimiento entre los integrantes de una organización. Se presenta a partir del FGC un prototipo de Sistema de Gestión del Conocimiento (SGC) orientado al manejo del conocimiento de grupos de investigación

Modelo de gestión de conocimiento para un Joint-Venture sistemático entre la Facultad Tecnológica de la Universidad Distrital y el sector del software

La interacción universidad-empresa se ha hecho necesaria para incrementar la productividad de ambos agentes en la sociedad. Sin embargo, suelen trabajar en sentidos contrarios: la universidad se encarga de la producción del conocimiento mediante la investigación e innovación; mientras que las empresas implantan la tecnología dentro de los procesos productivos y comercializan artículos y servicios en el mercado. Si bien ambos agentes tienen necesidades complementarias, en el caso colombiano no existe una unión semántica. En consecuencia, este artículo pretende construir un modelo de gestión que articule el conocimiento con las necesidades, tanto universitarias como empresariales, para así maximizar el beneficio de la sociedad como conjunto. Así mismo, expone el avance parcial en el desarrollo y la evaluación de un modelo piloto –prototipo– de cooperación entre la Facultad Tecnológica de la Universidad Distrital y algunas empresas del sector del software en Bogotá D.C. (Colombia) –implementado por medio de la construcción de un portal web. La lectura de éste trabajo da cuenta de experiencias basadas en el acercamiento mutuo entre universidades y diferentes sectores productivos del país

Productivity, cold hardiness and forage quality of spineless progeny of the Opuntia ficus−indica 1281 x O. lindheimerii 1250 cross in Mendoza plain, Argentina

Abstract The specialized photosynthetic system, Crassulacean Acid Metabolism (CAM) in cactus that provides several fold greater conversion of water to dry matter (DM) than grasses and broadleaf plants makes them especially suited for forage production in arid lands. Unfortunately the spineless fast growing Opuntia ficus−indica, that is widely used for forage in Brazil, North Africa and Mexico, is poorly adapted to regions outside the tropics due to lack of tolerance to freezing weather. To overcome this limitation, a wide interspecific cross was made between a fast growing, spineless, frost sensitive O. ficus−indica and spiny, cold tolerant, slow growing Texas native O. lindheimerii with the objective of combining the high productivity and spinelessness of the O. ficus−indica parent with the cold hardiness of the Texas native parent. The first part of this work compared 10 spineless progeny of this cross to the most cold hardy spineless forage species to date, i.e. O. ellisiana for forage production and crude protein (CP) content in Mendoza, Argentina (520 m elevation and 33º S latitude), where O. ficus−indica does not survive winters. Some of these progeny had 5 times greater productivity than O. ellisiana with equivalent cold tolerance. As previous Argentine Opuntia productivity trials were N limited, the responsiveness of these progeny to 3 rates of N fertilization was examined. It was found that N application stimulated about a 4 fold increases in dry biomass per plant compared to the treatment in which N was not added (12.7 and 3.2 kg DM plant −1 , respectively) and an almost doubling in CP content of the 1−year−old cladodes (7.8 and 4.3% DM, respectively). None of the CP concentrations were high enough to meet the requirements of a 400−kg live weight lactating cow (10%), but the dose/N response did not appear to have reached a plateau. To determine the productivity per unit area, one trial with clone 42 was established. This clone produced a biomass of 40 t DM ha −1 in 4 years with a total of 625 mm rainfall. This is the greatest DM production recorded to date for such a low rainfall. This DM production corresponds to a carrying capacity of 0.76 Animal Unit (AU) ha −1 . Future trials with the most productive and cold hardy of these spineless hybrid progeny, in combination with higher N fertilization levels that can meet lactating cow requirements are needed in additional test sites with more severe freezing weather regimes. Also, would be important to compare different ways to capture fertilizers such as to apply frequent, low application rates instead of an annual application as we done in the present study, taken into account the characteristics of the root mass of Opuntia. J. PACD (2011) 13: 48−62 49 Other interesting alternative to prove for reducing the use of N−fertilizer could be to test if endophytic nitrogen−fixing bacteria such as Gluconacetobacter diazotrophicus fixes N with Opuntia

Generación de señales ECG con funciones de fourier en un microcontrolador de arquitectura ARM 32

Bioelectrical events manifest themselves as potential differences between two points or electrical signals located in different parts of a living organism, either inside or on its surface. The behavior of these events reflects the health of a human being and to determine them, vital signs are checked. To obtain a proper diagnosis, among some vital signs, is the electrocardiogram (ECG). Therefore, it is necessary to know and reproduce this signal to diagnose any condition or to make sure that the equipment that acquires the signal works properly. This motivated the development of the present work, which presents the emulation of an ECG signal through the sum of Fourier harmonics in a 32-bit ARM STM STM32f407VGT architecture microcontroller, due to its design features and its application to embedded systems, as well as the performance in terms of peripherals available to reproduce the signal. As the Electrocardiogram ECG signal is a periodic signal, with a fundamental frequency determined by the heart rate frequency, it satisfies the Dirichlet conditions, which states that for the Fourier series to exist, its coefficients are finite. The main contribution of this work was to generate EGC signals in an artificial way, which can be useful for medical training or calibration of measuring instruments.Los eventos bioeléctricos se manifiestan como diferencias de potencial entre dos puntos o señales eléctricas localizadas en diferentes lugares de un organismo viviente, ya sea dentro o en la superficie de este, el comportamiento de estos refleja la salud de un ser humano y para determinarlos se verifican los signos vitales. Para obtener un diagnóstico adecuado, entre algunas señales vitales, se encuentra el electrocardiograma (ECG). Por ello, es necesario conocer y reproducir esta señal para diagnosticar algún padecimiento o bien asegurarse que el equipo que adquiere la señal funciona adecuadamente. Esto motivó el desarrollo del presente trabajo, que presenta la generación artificial de una señal ECG a través de la suma de armónicos de Fourier en un microcontrolador de arquitectura ARM ST STM32f407VGT de 32 bits, debido a sus características de diseño y su aplicación a sistemas embebidos, así como las prestaciones en cuestión de periféricos disponibles para reproducir la señal. Como la señal Electrocardiograma ECG es una señal periódica, con una frecuencia fundamental determinada por la frecuencia de ritmo cardiaco, satisface las condiciones de Dirichlet, que plantea que para que la serie de Fourier exista, sus coeficientes son finitos. La contribución principal de este trabajo fue generar señales EGC de manera artificial, que pueda ser útil para entrenamiento médico o calibración de instrumental de medición

Rarity of monodominance in hyperdiverse Amazonian forests.

Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors

Occupational Heat Exposure and Breast Cancer Risk in the MCC-Spain Study

[EN] Background: Mechanisms linking occupational heat exposure with chronic diseases have been proposed. However, evidence on occupational heat exposure and cancer risk is limited. Methods: We evaluated occupational heat exposure and female breast cancer risk in a large Spanish case-control study. We enrolled 1,738 breast cancer cases and 1,910 frequency-matched population controls. A Spanish job-exposure matrix, MatEmEsp, was used to assign estimates of the proportion of workers exposed (P >= 25% for at least 1 year) and work time with heat stress (wet bulb globe temperature ISO 7243) for each occupation. We used three exposure indices: ever versus never exposed, lifetime cumulative exposure, and duration of exposure (years). We estimated ORs and 95% confidence intervals (CI), applying a lag period of 5 years and adjusting for potential confounders. Results: Ever occupational heat exposure was associated with a moderate but statistically significant higher risk of breast cancer (OR 1.22; 95% CI, 1.01-1.46), with significant trends across categories of lifetime cumulative exposure and duration (P-trend = 0.01 and 0.03, respectively). Stronger associations were found for hormone receptor-positive disease (OR ever exposure = 1.38; 95% Cl, 1.12-1.67). We found no confounding effects from multiple other common occupational exposures; however, results attenuated with adjustment for occupational detergent exposure. Conclusions: This study provides some evidence of an association between occupational heat exposure and female breast cancer risk.SIThis study was partially funded by the “Accion Transversal del Cancer,” approved by the Spanish Ministry Council on October 11, 2007; the Instituto de Salud Carlos III-FEDER (PI08/1770, PI08/1359, PI09/00773, PI09/01286, PI09/01903, PI09/02078, PI09/01662, PI11/01403, PI11/01889, and PI12/00265); the Fundación Marqués de Valdecilla (API 10/09); the Junta de Castilla y León (LE22A10-2); the Consejería de Salud of the Junta de Andalucía (2009-S0143); the Conselleria de Sanitat of the Generalitat Valenciana (AP_061/10); the Recercaixa (2010ACUP 00310); the Regional Government of the Basque Country; the Consejería de Sanidad de la Región de Murcia; the European Commission grants FOOD-CT-2006–036224-HIWATE; the Spanish Association Against Cancer (AECC) Scientific Foundation; the Catalan Government DURSI grant 2014SGR647; the Secretariat for Universities and Research of the Ministry of Business and Knowledge of the Government of Catalonia (2017SGR1085); the Fundación Caja de Ahorros de Asturias; and the University of Oviedo. M.C. Turner is funded by a Ramón y Cajal fellowship (RYC-2017-01892) from the Spanish Ministry of Science, Innovation and Universities and co-funded by the European Social Fund. The authors acknowledge support from the Spanish Ministry of Science and Innovation through the “Centro de Excelencia Severo Ochoa 2019–2023” Program (CEX2018-000806-S) and support from the Generalitat de Catalunya through the CERCA Program. Statistical assistance provided by Ana Espinosa Morano was greatly appreciated

First wave of COVID-19 in Venezuela:Epidemiological, clinical, and paraclinical characteristics of first cases

The coronavirus disease 2019 (COVID-19) pandemic has particularly affected countries with weakened health services in Latin America, where proper patient management could be a critical step to address the epidemic. In this study, we aimed to characterize and identify which epidemiological, clinical, and paraclinical risk factors defined COVID-19 infection from the first confirmed cases through the first epidemic wave in Venezuela. A retrospective analysis of consecutive suspected cases of COVID-19 admitted to a sentinel hospital was carried out, including 576 patient cases subsequently confirmed for severe acute respiratory syndrome coronavirus 2 infection. Of these, 162 (28.1%) patients met the definition criteria for severe/critical disease, and 414 (71.2%) were classified as mild/moderate disease. The mean age was 47 (SD 16) years, the majority of which were men (59.5%), and the most frequent comorbidity was arterial hypertension (23.3%). The most common symptoms included fever (88.7%), headache (65.6%), and dry cough (63.9%). Severe/critical disease affected mostly older males with low schooling (p < 0.001). Similarly, higher levels of glycemia, urea, aminotransferases, total bilirubin, lactate dehydrogenase, and erythrocyte sedimentation rate were observed in severe/critical disease patients compared to those with mild/moderate disease. Overall mortality was 7.6% (44/576), with 41.7% (28/68) dying in hospital. We identified risk factors related to COVID-19 infection, which could help healthcare providers take appropriate measures and prevent severe clinical outcomes. Our results suggest that the mortality registered by this disease in Venezuela during the first epidemic wave was underestimated. An increase in fatalities is expected to occur in the coming months unless measures that are more effective are implemented to mitigate the epidemic while the vaccination process is ongoing