56 research outputs found
Desarrollo de un centro de atención a niños maltratados
Capítulo de la sección: Comunicación y sociedad sustentableDentro del contexto del fenómeno médicosocial conocido en el argot médico como Síndrome del Niño Maltratado (SNM), existen algunos aspectos que merecen ser precisados para que tanto profesionales de la salud como sociedad en general, estén adecuadamente informados de cómo, cuándo y en donde se puede presentar el problema y de esta manera entender la enorme necesidad de que este tipo de organizaciones funcionen en todos los hospitales pediátricos mientras grupos de investigadores diseñan estrategias básicamente de prevención, acción que finalmente debe ser apoyada por el Gobierno Federal, Estatal y/o Municipal si queremos de alguna manera frenar esta patología
Factorización de Hadamard para polinomios Hurwitz
Los polinomios Hurwitz o estables juegan un papel importante en el estudio de sistemas de ecuaciones diferenciales y en la teoría de control. Una propiedad importante de dichos polinomios está relacionada con el producto de Hadamard. En décadas pasadas se probó que si p, q ∈ R[x] son dos polinomios Hurwitz, entonces su producto de Hadamard, denotado por (p ∗ q), es también un polinomio Hurwitz, es decir el producto de Hadamard preserva la estabilidad. Sin embargo la afirmación recíproca no siempre es cierta; es decir, no todos los polinomios Hurwitz pueden factorizarse como producto de dos polinomios estables del mismo grado n, si n ≥ 4. En este trabajo presentamos algunos resultados para garantizar la existencia de dicha factorización, a la que hemos denominado factorización estable de Hadamard
Stability and multiscroll attractors of control systems via the abscissa
"We present an approach to generate multiscroll attractors via destabilization of piecewise linear systems based on Hurwitz matrix in this paper. First we present some results about the abscissa of stability of characteristic polynomials from linear differential equations systems; that is, we consider Hurwitz polynomials. The starting point is the Gauss–Lucas theorem, we provide lower bounds for Hurwitz polynomials, and by successively decreasing the order of the derivative of the Hurwitz polynomial one obtains a sequence of lower bounds. The results are extended in a straightforward way to interval polynomials; then we apply the abscissa as a measure to destabilize Hurwitz polynomial for the generation of a family of multiscroll attractors based on a class of unstable dissipative systems (UDS) of affine linear type.
Stability and Multiscroll Attractors of Control Systems via the Abscissa
We present an approach to generate multiscroll attractors via destabilization of piecewise linear systems based on Hurwitz matrix in this paper. First we present some results about the abscissa of stability of characteristic polynomials from linear differential equations systems; that is, we consider Hurwitz polynomials. The starting point is the Gauss–Lucas theorem, we provide lower bounds for Hurwitz polynomials, and by successively decreasing the order of the derivative of the Hurwitz polynomial one obtains a sequence of lower bounds. The results are extended in a straightforward way to interval polynomials; then we apply the abscissa as a measure to destabilize Hurwitz polynomial for the generation of a family of multiscroll attractors based on a class of unstable dissipative systems (UDS) of affine linear type
Estabilidad de sistemas por medio de polinomios Hurwitz
"Para analizar la estabilidad de un sistema de ecuaciones diferenciales lineales x=Axpodemos estudiar la localización de las raíces del polinomio característico pA(t) asociado a la matriz A. En este artículo presentamos diversos criterios algebraicos y geométricos que nos ayudan a determinar el lugar donde se encuentran las raíces sin necesidad de calcularlas en forma directa.
Administración y sustentabilidad
1 archivo PDF (xxvii, 365 páginas) ; 2a ed., corregida y aumentadaLa sustentabilidad desde las instituciones obliga a pensar en la necesidad de administradores que rebasen el discurso
de la técnica, que sean capaces de realizar un trabajo transdisciplinario, lo cual los obliga a su vez a una continua formación sobre la dimensión política y económica de los sectores en los que se insertan a trabajar, en la búsqueda de las condiciones que hagan posible un desarrollo sustentable. El presente material queda organizado bajo tres grandes
rubros: El primero, Desarrollo sustentable: naturaleza y economía el segundo, Comunicación y sociedad sustentable y el tercero, Educación y sustentabilidad; el trabajo de la Maestra Ma. Luisa Murga Meler quedará como un análisis crítico sobre el desarrollo sustentable y tendrá lugar particular al final de esta compilación
Modelado del tiempo fisiológico de Ceratitis capitata mediante sensores remotos en territorios estratégicos de Centroamérica.
The Mediterranean fly is a quarantine pest that can directly affect the production and marketing of fruits and vegetables worldwide. It is a species with polyphagous behavior and has a high number of susceptible hosts, both wild and economically important. Currently, in Central America and Southern Mexico, there are strategic territories with permanent monitoring of the pest, which act as barriers in its advance towards North America. The use of remote sensors in the phytosanitary area has the potential to contribute to decision-making in the establishment of preventive strategies to mitigate the advance and phytosanitary risk of Ceratitis capitata. It can even be considered a geotechnological tool that contributes to the processes of monitoring and surveillance of health risks, through the analysis of environmental information, particularly the thermal component. Temperature is an essential factor for the immature and adult stages of the Medfly. The objective of this study was to design the physiological time of C. capitata through the calculation of accumulated heat units (UCAcum) in strategic territories. Specifically, the study aimed to model and calculate the physiological time of C. capitata through the accumulated heat units (UCAcum) in the potential containment, containment, and eradication zones using ERA5 data.
A spatiotemporal pattern was obtained for the period from December 2020 to December 2021, showing the monthly thermal behavior that favors C. capitata on two scales: a regional scale that included the countries of El Salvador, Honduras, Guatemala, and southern Mexico, and the previously defined strategic zones.
The study revealed a monthly thermal oscillation from 13,1 to 37,4°C, considering extreme temperatures. The surfaces with optimal thermal accumulation, determining the physiological time of the pest, were identified based on the fact that C. capitata requires 251,7 UCAcum to complete a life cycle. In the potential containment zone, 463,4 UCAcum were determined for portions of Honduras and El Salvador. In the containment zone in Guatemala, 418,8 UCAcum were identified, and finally, in the eradication zone, an accumulation of 401.3 units was observed in Guatemala and the Pacific coast in the Mexican southeast. This spatial analysis showed that the physiological time presented a uniform behavior in strategic territories.
Modeling UCAcum from remote sensing strengthens strategic decision-making regarding health risks. The strength of this approach lies in the accessibility of freely available inputs and recent temporality, allowing the creation of risk scenarios under a preventive approach in almost real-time (with a three-week delay). Thermal comfort modeling should be considered a contributing input to effectively direct preventive strategies by the National and Regional Plant Protection Organizations. These organizations are responsible for implementing mitigation strategies before the arrival of pests or diseases that endanger the global agro alimentary heritage.La mosca del Mediterráneo es una plaga cuarentenaria que puede afectar de manera directa la producción y comercialización de frutas y hortalizas en el mundo, es una espacie con un comportamiento polífago y cuenta con un gran número de hospedantes susceptibles tanto silvestres como de importancia económica. Actualmente, en Centroamérica y Sur de México existen territorios estratégicos en los que se mantiene un monitoreo permanente de la plaga los cuales se consideran una barrera en su avance hacia el norte del continente. La utilización de sensores remotos en el área de la fitosanidad tiene el potencial de aportar a la toma de decisiones en el establecimiento de estrategias preventivas de mitigación de avance y riesgo fitosanitario de Ceratitis capitata, incluso, se puede considerar una herramienta geotecnológica que permite coadyuvar en los procesos de monitoreo y vigilancia de riesgos sanitarios, a través del análisis de información ambiental, en este caso, del componente térmico, puesto que la temperatura es un factor esencial para los estados inmaduros y adultos de la mosca del Mediterráneo. El objetivo del presente estudio fue diseñar el tiempo fisiológico de C. capitata a través del cálculo de las unidades calor acumuladas (UCAcum) en territorios estratégicos (zona de contención potencial, de contención y de erradicación), mediante el uso de imágenes satelitales climáticas ERA5. Se obtuvo un patrón espacio-temporal del periodo comprendido entre diciembre de 2020 a diciembre de 2021 del comportamiento térmico mensual que favorece a C. capitata en dos escalas: regional que abarcó los países de El Salvador, Honduras, Guatemala y sur de México, así como en las zonas estratégicas antes definidas. Se evidenció que durante 2021 existió una oscilación térmica mensual de 13,1 a 37,4°C, consideradas las temperaturas extremas. De manera específica, se identificaron las superficies donde existió la acumulación térmica óptima que determina el tiempo fisiológico de la plaga, basados en que C. capitata requiere de 251,7 UCAcum para lograr un ciclo de vida. Se determinó que en la zona de contención potencial se acumularon 463,4 unidades en porciones de Honduras y El Salvador. En la zona de contención ubicada en Guatemala se determinó 418,8 UCAcum y finalmente en la zona de erradicación se logró una acumulación de 401,3 unidades en Guatemala y costa del Pacifico en el sureste mexicano, lo que permitió espacializar que el tiempo fisiológico presentó un comportamiento uniforme en los territorios estratégicos. Diseñar o modelar UCAcum a partir de sensores remotos posibilita fortalecer decisiones estratégicas ante riesgos sanitarios, y tiene como fortaleza que son insumos de libre acceso y de una temporalidad reciente, lo que permite crear escenarios de riesgo bajo un enfoque preventivo en tiempo casi real (con un retraso de unas semanas). La modelación del confort térmico debería ser considerada un insumo coadyuvante para direccionar de manera efectiva estrategias preventivas por parte de los Organismos Nacionales y Regionales de Protección Fitosanitaria que se encargan de recomendar acciones ante el arribo de plagas o enfermedades que ponen en riesgo el patrimonio agroalimentario mundial
DETECCIÓN DE ESCHERICHIA COLI O157:H7 EN CARNE FRESCA DE RES MEDIANTE PCR MÚLTIPLEX
Para la detección de E. coli O157:H7 en carne fresca de res, se comparó el método microbiológico tradicional y dos ensayos de PCR Múltiplex. En ensayos con muestras inoculadas se obtuvo una diferencia significativa entre PCR Múltiplex y aislamiento microbiológico. PCR Múltiplex mostró porcentaje mayor de sensibilidad, precisión relativa e índice kappa en el enriquecimiento con el caldo Ecm+n en comparación al CST+ccv. En 40 muestras de res corte tipo americano se detectaron 2 positivas (5%) por PCR múltiplex, mientras que por el método microbiológico no se logró su aislamiento en ninguna muestra. AbstractIn the present study were compared the traditional microbiological method and two tests of multiplex PCR for the detection of E. coli O157:H7 in fresh beef meat. A significant difference was obtained between PCR multiplex and microbiological isolation in inoculated samples; in addition, in multiplex PCR was obtained a higher percentage of sensitivity, precision relative and Kappa index using the Ecm+n broth in comparison to the CST+ccv in the enrichment. In 40 samples of meat cuts American type were detected two positive samples (5%) by Multiplex PCR, whereas by the microbiological method was not obtained the isolation in any sample. Palabras clave: PCR Múltiplex, E. coli O157:H7, Carne, Beef
Activity of Thioallyl Compounds From Garlic Against Giardia duodenalis Trophozoites and in Experimental Giardiasis
Fresh aqueous extracts (AGEs) and several thioallyl compounds (TACs) from garlic have an important antimicrobial activity that likely involves their interaction with exposed thiol groups at single aminoacids or target proteins. Since these groups are present in Giardia duodenalis trophozoites, in this work we evaluated the anti-giardial activity of AGE and several garlic's TACs. In vitro susceptibility assays showed that AGE affected trophozoite viability initially by a mechanism impairing cell integrity and oxidoreductase activities while diesterase activities were abrogated at higher AGE concentrations. The giardicidal activities of seven TACs were related to the molecular descriptor HOMO (Highest Occupied Molecular Orbital) energy and with their capacity to modify the –SH groups exposed in giardial proteins. Interestingly, the activity of several cysteine proteases in trophozoite lysates was inhibited by representative TACs as well as the cytopathic effect of the virulence factor giardipain-1. Of these, allicin showed the highest anti-giardial activity, the lower HOMO value, the highest thiol-modifying activity and the greatest inhibition of cysteine proteases. Allicin had a cytolytic mechanism in trophozoites with subsequent impairment of diesterase and oxidoreductase activities in a similar way to AGE. In addition, by electron microscopy a marked destruction of plasma membrane and endomembranes was observed in allicin-treated trophozoites while cytoskeletal elements were not affected. In further flow cytometry analyses pro-apoptotic effects of allicin concomitant to partial cell cycle arrest at G2 phase with the absence of oxidative stress were observed. In experimental infections of gerbils, the intragastric administration of AGE or allicin decreased parasite numbers and eliminated trophozoites in experimentally infected animals, respectively. These data suggest a potential use of TACs from garlic against G. duodenalis and in the treatment of giardiasis along with their additional benefits in the host's health
Albiglutide and cardiovascular outcomes in patients with type 2 diabetes and cardiovascular disease (Harmony Outcomes): a double-blind, randomised placebo-controlled trial
Background:
Glucagon-like peptide 1 receptor agonists differ in chemical structure, duration of action, and in their effects on clinical outcomes. The cardiovascular effects of once-weekly albiglutide in type 2 diabetes are unknown. We aimed to determine the safety and efficacy of albiglutide in preventing cardiovascular death, myocardial infarction, or stroke.
Methods:
We did a double-blind, randomised, placebo-controlled trial in 610 sites across 28 countries. We randomly assigned patients aged 40 years and older with type 2 diabetes and cardiovascular disease (at a 1:1 ratio) to groups that either received a subcutaneous injection of albiglutide (30–50 mg, based on glycaemic response and tolerability) or of a matched volume of placebo once a week, in addition to their standard care. Investigators used an interactive voice or web response system to obtain treatment assignment, and patients and all study investigators were masked to their treatment allocation. We hypothesised that albiglutide would be non-inferior to placebo for the primary outcome of the first occurrence of cardiovascular death, myocardial infarction, or stroke, which was assessed in the intention-to-treat population. If non-inferiority was confirmed by an upper limit of the 95% CI for a hazard ratio of less than 1·30, closed testing for superiority was prespecified. This study is registered with ClinicalTrials.gov, number NCT02465515.
Findings:
Patients were screened between July 1, 2015, and Nov 24, 2016. 10 793 patients were screened and 9463 participants were enrolled and randomly assigned to groups: 4731 patients were assigned to receive albiglutide and 4732 patients to receive placebo. On Nov 8, 2017, it was determined that 611 primary endpoints and a median follow-up of at least 1·5 years had accrued, and participants returned for a final visit and discontinuation from study treatment; the last patient visit was on March 12, 2018. These 9463 patients, the intention-to-treat population, were evaluated for a median duration of 1·6 years and were assessed for the primary outcome. The primary composite outcome occurred in 338 (7%) of 4731 patients at an incidence rate of 4·6 events per 100 person-years in the albiglutide group and in 428 (9%) of 4732 patients at an incidence rate of 5·9 events per 100 person-years in the placebo group (hazard ratio 0·78, 95% CI 0·68–0·90), which indicated that albiglutide was superior to placebo (p<0·0001 for non-inferiority; p=0·0006 for superiority). The incidence of acute pancreatitis (ten patients in the albiglutide group and seven patients in the placebo group), pancreatic cancer (six patients in the albiglutide group and five patients in the placebo group), medullary thyroid carcinoma (zero patients in both groups), and other serious adverse events did not differ between the two groups. There were three (<1%) deaths in the placebo group that were assessed by investigators, who were masked to study drug assignment, to be treatment-related and two (<1%) deaths in the albiglutide group.
Interpretation:
In patients with type 2 diabetes and cardiovascular disease, albiglutide was superior to placebo with respect to major adverse cardiovascular events. Evidence-based glucagon-like peptide 1 receptor agonists should therefore be considered as part of a comprehensive strategy to reduce the risk of cardiovascular events in patients with type 2 diabetes.
Funding:
GlaxoSmithKline
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