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Carbohydrate intake is one of the main disturbances in blood glucose metabolism and one of the major care-issues in diabetes therapy. For this reason, the dynamics of glucose absorption after a meal intake must be included in glucose metabolism models. Current interest in developing patient-specific models has shown the necessity to estimate key parameters in models of carbohydrate intake, which cannot be measured with available sensor technology. In this contribution, we present a scheme to estimate a parameter and a state related to absorption of glucose in the intestine, which depend on the amount of carbohydrates ingested in a meal. The scheme is based on an adaptive observer with exponential convergence to estimate states and uncertain constant parameters.

Currently, closed-loop therapy is a promising option for individuals with type 1 diabetes mellitus. It requires a glucose metabolism model and a control algorithm to reach a suitable automatic insulin delivery. Many mathematical models have been proposed considering the glucose-insulin dynamics and nominal parameters of a standard patient. Nevertheless, the open-loop therapy based on continuous glucose monitoring (CGM) and continuous subcutaneous insulin infusion (CSII) provides sufficient data to seek patient-oriented models instead of the nominal ones. In consequence, patient-oriented models could open the possibility of having personalized closed-loop therapies. In this work, a methodology for automatic adjustment of sensitive parameters of a physiological mathematical model of glucose metabolism is presented. The methodology is based on an evolutionary algorithm and it is exemplified with a physiological model. This methodology provides a criterion to select the best model which can reproduce the glucose-insulin dynamics of a diabetic patient according to the data provided by the CGM and CSII systems.

Abstract: Chromaffin cells secrete catecholamine molecules via exocytosis process. Each exocytotic event is characterized by a current spike, which corresponds to the amount of released catecholamine from secretory vesicles after fusing to plasma membrane. The current spike might be measured by the oxidation of catecholamine molecules and can be experimentally detected through amperometry technique. In this contribution, the secretion of catecholamine, namely adrenaline, of a set of bovine chromaffin cells is measured individually at each single cell. The aim is to study quantitative results of chaotic behavior in catecholamine secretion. For analysis, time series were obtained from amperometric measurements of each single chromaffin cell. Three analysis techniques were exploited: (i) A low-order attractor was generated by means of phase space reconstruction, Average Mutual Information (AMI) and False Nearest Neighbors (FNN) were used to compute embedding lag and embedding dimension, respectively. (ii) The properties of power spectrum density of time series were studied by Fast Fourier Transform (FFT) looking for possible dominant frequencies in power spectrum. (iii) Maximun Lyapunov Exponent (MLE) analysis was done to study the divergence of trajectories of the time series. Nevertheless, in order to dismiss the possibility of positiveness of MLE are due to the inherent noise in experiments, seven surrogate data sets computed using the Amplitude Adjusted Fourier Transform (AAFT) algorithm was computed. The phase space reconstruction showed that, in all cases, the trajectories lie in an embedding subspace suggesting oscillatory nature. The FFT analysis showed high dispersion of the power spectrum without any predominant frequency range. MLE analysis showed that the MLE values are positive for a given orbit time and a defined range of maximum scale values. Moreover, the trajectory of the MLE evolution of all the surrogate data are asymptotic and hold positive along the maximum scale range. These findings are preliminary evidence on detecting chaotic behavior in catecholamine secretion and, in general, their provide a first step towards a deeply understanding of nonlinear behavior of protein releasing dynamics. [Copyright &y& Elsevier]

Abstract: Compartmental-Physiological Models (CPM’s) have been used to derive feedback controllers for the glucose regulation in Diabetes Mellitus (DM). Despite these important advances, there are two criticisms about the use of the CPM’s in DM: (i) Can this class of model reproduce severe basal glucose levels (e.g., larger than 300mg/dl)? and (ii) Does a CPM reproduce a distinct glucose level as its parameters change or is it unique even if its parameters change? This contribution aims these criticisms from the study of the parametric sensitivity of a CPM. The results exploit the analysis of the dynamic properties of the chosen CPM and permit to show that such model can reproduce distinct severe basal levels by modifying the values of the metabolic parameters, which agree with expectations on a realistic model. Mainly, the chosen CPM has been selected due to the following two reasons. (i) It includes the main organs related to the glucose metabolism in Type 1 Diabetes Mellitus (T1DM); as, for example, the liver, brain and kidney. (ii) It models metabolic phenomena as, for instance, the counter-regulatory effects by glucagon and the hepatic glucose uptake/production. Additionally, the chosen model has been recently used to design feedback controllers for the glucose regulation with very promissory results. [Copyright &y& Elsevier]

Tuberculosis (TB) rates remain high in regions of Southern Mexico despite the existence of a National Tuberculosis Program. Understanding TB epidemiology in such settings would assist in the design of improved TB control and highlight the challenges confronting TB control in developing countries.

We examine arguments about the scientific status of repression and dissociation in the written discourse of academic social scientists and clinicians on the controversial issue of recovered memories of child sexual abuse. The rhetorical deployment of theories, methods, and evidence by representatives of both camps regarding the authenticity of recovered memories, repression, and dissociation is compared. The ways in which supporters and sceptics bolster claims for their own expertise while undermining that of opponents are also explored. Supporters of recovered memory emphasise the pragmatic relevance of theories and clinical evidence, while sceptics draw rhetorically on positivist standards of scientific rigour and reliability to undermine claims of recovered memory. The themes of relevance and reliability are then related to discussions of recent legal changes in the United States on the admissibility of expert opinion evidence in recovered memory cases. [ABSTRACT FROM AUTHOR]

El aprovechamiento maderable modifica los patrones de partición y acumulación de biomasa estructural y de compartimentos del bosque; determinar dicha acumulación es importante para conocer el efecto de los tratamientos silvícolas (TS) aplicados. El objetivo de este trabajo fue analizar biomasa aérea y carbono (C) del suelo en rodales bajo TS aplicados en el periodo 2013-2014, en San Juan Lachao, Oaxaca. En 2022 se establecieron de manera selectiva 12 sitios (UM) en cuatro tratamientos, tres TS: 1er aclareo (1A), aclareo libre (AL), corta de regeneración (CR), y un área sin manejo (ASM). Se realizó inventario arbóreo y del piso forestal y sotobosque, para estimar la biomasa estructural y de compartimentos. Los tratamientos se diferenciaron mediante modelo lineal generalizado y comparación de medias (Duncan, 0.05); las UM se clasificaron mediante análisis clúster. Los tratamientos generan montos diferenciados (p < 0.01) en la biomasa de arbustos, hojarasca, humus y densidad aparente del suelo; pero no en la biomasa aérea total (p > 0.05). El área con CR mostró la mayor cantidad de biomasa en el compartimento herbáceo y arbustivo con 0.24 t [ha.sup.-1] y 3.80 t [ha.sup.-1], respectivamente. ASM, AL y 1A mostraron diferencia significativa de biomasa en humus (p < 0.01) en comparación con CR (3.93 t [ha.sup.-1]), con incrementos respectivos de 160%, 265% y 275%. El ASM presentó la mayor acumulación de biomasa aérea total (180.49 t [ha.sup.-1]), mientras que los TS, en promedio, registraron 166.97 t [ha.sup.-1]. El contenido de materia orgánica (11.6%) y C (6.7%) en el suelo del ASM fue significativamente diferente (p [menor que o igual a] 0.01) al de los TS. Los TS modifican la biomasa de los compartimentos del piso forestal, lo cual puede revertirse con la aplicación de tratamientos complementarios. PALABRAS CLAVE: aclareo, biomasa estructural, compartimentos, densidad del suelo, materia orgánica, San Juan Lachao. Timber harvesting modifies the patterns of partition and accumulation of structural biomass and forest compartments; determining this accumulation is important to know the effect of the silvicultural treatments (TS) applied. The objective was to analyze the aboveground biomass and soil carbon (C) in stands under TS applied in the period 2013-2014, in San Juan Lachao, Oaxaca. In 2022, 12 sites (UM) were selectively established in four treatments, three TS: 1st thinning (1A), free thinning (AL), regeneration cutting (CR), and an unmanaged area (ASM). Tree and forest floor inventory was carried out and undergrowth, to estimate structural and compartment biomass. The treatments were differentiated using a generalized linear model and comparison of means (Duncan, 0.05); The MUs were classified by cluster analysis. The treatments generate different amounts (p < 0.01) in the biomass of shrubs, leaf litter, humus and apparent density of the soil; but not in the total aboveground biomass (p > 0.05). The area with CR showed the highest amount of biomass in the herbaceous and shrubby compartment with 0.24 t [ha.sup.-1] and 3.80 t [ha.sup.-1], respectively. The ASM, AL and 1A showed a significant difference in biomass in humus (p < 0.01) compared to CR (3.93 t [ha.sup.-1]), with respective increases of 160%, 265% and 275%. The ASM presented the highest accumulation of total aboveground biomass (180.49 t [ha.sup.-1]), while the TS on average recorded 166.97 t [ha.sup.-1]. The content of organic matter (11.6%) and C (6.7%) in the ASM soil was significantly different (p [menor que o igual a] 0.01) from that of the TS. TS modify the biomass of the forest floor compartments, which can be reversed with the application of complementary treatments. KEYWORDS: thinning, structural biomass, compartments, soil density, organic matter, San Juan Lachao., Aboveground biomass and soil carbon in pine-oak stands under silvicultural treatments INTRODUCCIÓN En México y a escala global, el secuestro de carbono (C) proporcionado por los bosques es relevante debido [...]

La teoría de acción colectiva aplicada a los bosques de México ha sido una gran alternativa para estudiar el manejo de los paisajes forestales y los impactos socioeconómicos que se generan en los recursos de uso común. En este estudio se analizó el papel histórico de tres ejidos forestales en el estado de Durango en su organización y creación de instituciones internas para enfrentar cambios en la cobertura forestal. Se compararon dos periodos que abarcan desde la etapa de las concesiones forestales hasta el actual manejo forestal comunitario (1960-2018). Se utilizaron entrevistas semiestructuradas para estimar dos índices que relacionan la organización interna de las comunidades: el índice de organización social y el de institucionalidad comunitaria. Se usaron también las series cartográficas de Instituto Nacional de Estadtstica y Geografta para determinar los cambios en la cobertura forestal en el periodo antes mencionado. Con base en los principios de acción colectiva de Ostrom, se analizó la efectividad de estos ejidos en la conservación de sus recursos. Los resultados muestran que los índices han incrementado con el tiempo, sugiriendo que los ejidos han mejorado en sus procesos de organización interna. Además, se encontró que existe una relación directa entre el incremento de la superficie forestal y ambos índices. El modelo forestal comunitario es una estrategia factible que puede contribuir a la preservación de estos ecosistemas. El fortalecimiento de la organización interna de las comunidades, incluyendo sus acuerdos institucionales, es importante para ayudar a transitar hacia un desarrollo sustentable en este tipo de recursos de uso común. PALABRAS CLAVE: acción colectiva, cobertura forestal, institucionalidad comunitaria, manejo forestal comunitario, organización social, recursos de uso común. The theory of collective action applied to forest communities in Mexico has been a great alternative to study forest landscape conservation and the socioeconomic impacts generated in common pool resources. We analyzed the historical role of three forest ejidos in the State of Durango, including their organization and capacity building to deal with forest cover changes. Two periods ranging from the beginning of forest concessions to current community forest management (1960-2018) were compared. Semi-structured interviews were used to estimate two indexes that associate the internal organization of the communities: Social Organization Index and Community Institutionality Index. The cartographic series of the National Institute of Statistics and Geography were also used to determine the changes in forest cover within the analyzed period. Based on Ostrom's principles of collective action, the effectiveness of the ejidos in conserving their resources was analyzed. Results show that the indexes have increased over time, suggesting that ejidos have improved their organization processes. In addition, there is a direct relationship between the forest land increase and both indices. The so-called community forest management model is a feasible strategy that can contribute to the preservation of these ecosystems. The internal organization of the communities, including their institutional arrangements, is a key factor to search for the sustainable management of these common-pool resources. KEYWORDS: collective action, forest cover, community institutionality, community forest management, social organization, common-pool resources., INTRODUCCIÓN El régimen de propiedad colectiva que existe actualmente en la mayoría de las regiones forestales de México representa una visión única en el mundo y poco conocido por otros [...]

Oaxaca es la entidad mexicana con mayor biodiversidad; sin embargo, tiene pocas áreas naturales protegidas, las cuales son una de las estrategias gubernamentales más importantes para la conservación. Además, existen, de reciente creación y por decreto oficial, las áreas destinadas voluntariamente para la conservación y las áreas de uso común (con libre manejo por parte de los usuarios). Las tendencias de deforestación llaman la atención, por lo que es necesario saber qué está pasando con las arbóreas. En este estudio se compara la estructura y composición de leñosas (como organismos que definen los ecosistemas terrestres) entre los tres tipos de área, en dos diferentes regiones: la Mixteca con bosque de encino y Valles Centrales con selva baja caducifolia. En cada área, sobre un transecto, se trazaron 15 cuadros de 100 [m.sup.2] (parcelas) donde se registraron los individuos con diámetro a la altura del pecho [mayor que o igual a] 2.5 cm. Con el índice de Jaccard (datos florísticos de las parcelas) se evaluó la similitud entre áreas de cada región. Se estimaron diversidad, valor de importancia relativa, densidad, frecuencia y área basal. En los Valles Centrales con selva baja caducifolia se registraron 28 especies de 25 géneros y 13 familias; la similitud formó dos grupos y la densidad difirió significativamente. En la Mixteca con bosque de encino se registraron 51 especies de 37 géneros y 24 familias; la similitud articuló dos grupos y la riqueza difirió estadísticamente. La estructura de leñosas es similar entre áreas naturales protegidas y áreas de uso común de Valles Centrales. En la Mixteca, el área de uso común fue la más diversa. Palabras clave: áreas destinadas voluntariamente a la conservación, áreas de uso común, áreas naturales protegidas, bosque de encino, selva baja caducifolia. Oaxaca is the Mexican state that presents the highest level of biodiversity. The number of Protected Natural Areas (PNA) in this region is minimal, and they represent one important type of government conservation strategy; others include the recently created Areas Voluntarily Devoted to Conservation (AVDC), as well as Common Use Areas (CUA) that are managed freely by local users. Trends in deforestation compel us to question 'what processes are occurring in forested areas?' This study proposes a comparison of the structure and composition of woody plants (as organisms that define terrestrial ecosystems) among the three aforementioned types of protected areas within two different regions of Oaxaca, Mexico: the Mixteca region comprising oak forest (OF) and Valles Centrales consisting of dry tropical deciduous forest (DTDF). In each area, 15 quadrats of 100 [m.sup.2] (plots) were established along a transect where individual trees with the diameter at breast height [mayor que o igual a] 2.5 cm were recorded. The similitude among areas of each region was evaluated using the Jaccard Index (floristic data from plots). Diversity, Relative Importance Value (RIV), density, frequency and basal area were estimated. In the DTDF, 28 species belonging to 25 genera and 13 families were recorded; similitude formed two groups; density differed significantly. In the comprising oak forest, 51 species were recorded, belonging to 37 genera and 24 families; similitude formed two groups; richness presented statistically significant differences. Forest structure is similar between Protected Natural Areas and Common Use Areas in the Valles Centrales region. In the Mixteca region, the Common Use Area was the most diverse area. Keywords: areas voluntarily dedicated to conservation, common use areas, natural protected areas, oak forest, tropical dry deciduous forest., Introducción La transformación y degradación que sufren los ecosistemas está presente a escala global y local, debido a las diversas actividades de la población humana y al aumento del consumo [...]

Para entender la dinámica de la cobertura del suelo en el Parque Nacional Cofre de Perote, se hizo una comparación de las tasas de cambio de uso a dos escalas durante el periodo 1995-2004. A escala meso, se estudiaron estos patrones en toda la superficie del Parque Nacional Cofre de Perote, que es una de las 60 montañas prioritarias de México y también una importante área natural protegida del país ubicada en el estado de Veracruz. A escala micro el estudio se enfocó en el ejido El Conejo que se encuentra dentro de los límites de este parque nacional. Se utilizaron ortofotos digitales del gobierno federal para determinar el cambio en nueve categorías de uso del suelo. En ambas, meso y microescalas, se encontró que las categorías predominantes de cobertura son la agricultura y el bosque. Las probabilidades de cambio de cobertura del suelo en ambas escalas son bajas y tienen valores esencialmente iguales para la mayoría de las categorías de uso, reflejando tanto pequeñas ganancias en cobertura forestal en todo el parque como la efectividad del ejido en el manejo de recursos naturales dentro del parque. Se considera que los hallazgos de este estudio pueden ser aplicables a la situación prevaleciente en los restantes parques nacionales de México; al final se discute la importancia de integrar a los actores locales en el manejo de áreas naturales protegidas. PALABRAS CLAVE: cartografía, ejido El Conejo, matriz de transición, ortofotos digitales, Parque Nacional Cofre de Perote, uso del suelo. To understand the dynamics of land cover at the Parque Nacional Cofre de Perote, the rates of change in land use were compared at two different scales during the period 1995-2004. At the meso scale, these patterns were studied throughout the entire Parque Nacional Cofre de Perote, which is one of the 60 priority mountains of Mexico, and an important natural protected area of the country located in the state of Veracruz. At a micro scale, the work was focused in ejido El Conejo, located within the boundaries of this national park. Federal government digital orthophotos were used to determine changes in nine categories of land use. In both, the meso- and micro-scale, it was found that the predominant land cover categories are agriculture and forest. The probabilities of land cover change at both scales are low and essentially the same for most land use categories, reflecting both small gains in forest cover park-wide as well as the effectiveness of the ejido in managing natural resources within the park. The authors consider that the findings of the study may be applicable to the broader situation of national parks in Mexico and, finally, the importance of integrating local stakeholders in the management of natural protected areas is discussed. KEYWORDS: cartography, digital orthophotos, ejido El Conejo, land use, Parque Nacional Cofre de Perote, transition matrix., INTRODUCTION The drivers of deforestation worldwide are broad and complex, and involve many institutional, technological, socioeconomic and demographic factors (Hobbs, 1993; Lee, Carr and Lankerani, 1995; Collinge, 1996; Ghosh, 2004; [...]

Performance Improvement (PI), a process pioneered in industry, is now helping to strengthen reproductive health organizations. PI focuses on meeting the needs of service providers and other staff members. When [...]

2016 OCT 22 (NewsRx) -- By a News Reporter-Staff News Editor at Obesity, Fitness & Wellness Week -- Researchers detail new data in Oncology - Pancreatic Cancer. According to news [...]