202 research outputs found

    Propiedades ópticas y eléctricas de nanopartículas de sulfuro de cobre estabilizadas con ditiocarbamatos de cadena larga

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    En el documento se presentan los resultados de la preparación de nanoparticulas de sulfuro de cobre estabilizadas con DTC, su estudio de obtención, asi como caracterizaciones espectroscopicas y por microscopia para su identificacion. Se presenta tambien su estudio de las porpiedades opticas y termicas.In the present project copper sulfide nanoparticles were prepared by a chemical reaction between copper (II) complexes of long chained n-alkyldithiocarbamate (6, 12 and 18 carbon atoms) and sodium borohydride. The nanoparticles were characterized by infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, termogravimetric analysis and differential scanning calorimetry. In addition, the samples were characterized by diffuse reflectance spectroscopy in order to calculate the optical band gap energy of every case using the Kubelka-Munk theory. The results obtained demonstrate that the nanoparticles size average is around 10.0 nm distributed throughout the dithiocarbamate matrix. These particles present three different copper sulfide phases (covellite, digenite and chalcocite). Finally, the optical band gap energy is 3.4 eV in average

    Description of a hamartoma-type odontoma in Angelfish (Pterophyllum scalare)

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    Archivo de memoriaFish present the same variety of tumors as described in mammals and birds. Odontogenic tumors are related to alterations in epithelial and/or mesenchymal tissues involved in the formation and development of teeth. Histologically, the odontoma is a tumor characterized by abortive tooth formations and dental tissues (i.e. enamel, dentin, and cementum) that are normally formed but present a more or less disorganized pattern. In small fish species, odontogenic tumors have almost exclusively been described in angelfish (Pterophyllum scalare) and ocellaris clownfish (Amphiprion ocellaris). These tumors are macroscopically characterized as a nodular mass located in the frontal regions of the mouth. In angelfish these tumors have been described only as individual cases either as lip fibroma (in captive specimens) or as ameloblastoma (in wild specimens), but in this report we describe the occurrence of tumors in the frontal region of the mouth in a group of twenty aquarium angelfish.Conacyt, proyecto 287537 (UAEM 4618-2018-C

    AVALIAÇÃO DE SISTEMA DE COLUNAS PARA REMEDIAÇÃO DE BIOGÁS A PARTIR DE BIOMASSA NÃO DIGERIDA

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    O biogás é produto de reações de biomassa e constitui um combustível gasoso em temperatura ambiente, com conteúdo energético elevado comparável aos combustíveis de origem fósseis e semelhante ao gás natural. Devido a seu poder energético pode ser utilizado para geração de energia elétrica, térmica ou mecânica, levando a redução dos custos de produção. O processo de biodigestão anaeróbia consiste em metabolizar substâncias orgânicas complexas produzindo metano, dióxido de carbono, gases em menor quantidade (sulfídrico e hidrogênio) e material celular. Como subproduto da produção de metano, o dióxido de carbono é o que apresenta maior quantidade, e por ser um gás não-inflamável, pode ser definido como um subproduto indesejável da produção de biogás. Este trabalho teve como objetivo separar o dióxido de carbono, produzido na fermentação anaeróbica, por precipitação em reação com hidróxido de bário; o produto gerado é o carbonato de bário, o qual é tóxico e utilizado por diferentes indústrias. O processo adotado objetiva encontrar uma metodologia e aproveitar economicamente o dióxido de carbono gerado em biodigestores diminuindo o efeito estufa provocado pela emissão do mesmo no meio ambiente

    Práticas do disclosure voluntário socioambiental em cooperativas agropecuárias brasileiras

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    The objective of this article is to describe the voluntary disclosure of socio-environmental practices in Brazilian agricultural cooperatives. In order to reach the outlined objective, we analysed the annual reports on the websites of a non-probabilistic sample of the largest Brazilian agricultural cooperatives, referring to the period of 2015. For data analysis, the averages by subcategory and three indices of disclosure rate were used: Disclosure Index (DI), Business Disclosure Index (SDI) and General Business Disclosure Index (IGDE), General Index of Social Disclosure (IGDs). In addition, a fifth disclosure index was developed: the General Index of Environmental Disclosure (IGDa). The results obtained allow us to affirm that there is more disclosure of social information than environmental information, especially in relation to employees, concerns with the community and education, and that there is still a long way to go regarding good socio-environmental voluntary disclosure of agricultural and livestock cooperatives.O objetivo deste artigo é descrever o disclosure voluntário socioambiental em cooperativas agropecuárias brasileiras. A fim de atingir o objetivo traçado, foram analisados os relatórios anuais presentes nos websites de uma amostra não-probabilística das maiores cooperativas agropecuárias brasileiras, referentes ao período de 2015. Para a análise dos dados, foram utilizadas as médias por subcategoria e três índices de avalição de disclosure: Índice de Disclosure (ID), Índice de Disclosure das Empresas (IDE) e Índice Geral de Disclosure das Empresas (IGDE), Índice Geral de Disclosure social (IGDs). Além disso, foi desenvolvido um quinto índice de avaliação do disclosure: o Índice Geral de Disclosure ambiental (IGDa). Os resultados obtidos permitem afirmar que há mais divulgações de informações sociais do que ambientais, com destaque para, relação com empregados, preocupação com a comunidade e com educação, e que ainda falta muito para alcançar uma boa aderência de disclosure voluntário socioambiental pelas cooperativas agropecuárias analisadas

    First identification of Francisella noatunensis subsp. orientalis causing mortality in Mexican tilapia Oreochromis spp.

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    Articulo sobre la enfermedad Francisellosis en tilapias de MéxicoFrancisellosis, an emerging disease in tilapia Oreochromis spp., is caused by the facultative, intracellular bacterium Francisella noatunensis subsp. orientalis, which is present in various countries where tilapia farming is commercially important. We confirmed the presence of francisellosis in Mexican tilapia cultures in association with an outbreak during the second semester of 2012. Broodstock fish presented a mortality rate of approximately 40%, and disease was characterized by histologically classified granulomas, or whitish nodules, in different organs, mainly the spleen and kidney. Through DNA obtained from infected tissue and pure cultures in a cysteine heart medium supplemented with hemoglobin, F. noatunensis subsp. orientalis was initially confirmed through the amplification and analysis of the 16S rRNA gene and the internal transcribed spacer region. Phylogenetic analysis of these genes demonstrated close similarity with previously reported F. noatunensis subsp. orientalis sequences obtained from infected tilapia from various countries. The identification of this subspecies as the causative agent of the outbreak was confirmed using the iglC gene as a target sequence, which showed 99.5% identity to 2 F. noatunensis subsp. orientalis strains (Ethime-1 and Toba04). These findings represent the first documented occurrence of francisellosis in Mexican tilapia cultures, which highlights the importance of establishing preventative measures to minimize the spread of this disease within the Mexican aqua - culture industry.Proyecto Fondo semilla UAEM-UAch Clave 3334/2012FSChF and FONDAP/CONICYT 15110027

    SmartSantander: IoT experimentation over a smart city testbed

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    This paper describes the deployment and experimentation architecture of the Internet of Things experimentation facility being deployed at Santander city. The facility is implemented within the SmartSantander project, one of the projects of the Future Internet Research and Experimentation initiative of the European Commission and represents a unique in the world city-scale experimental research facility. Additionally, this facility supports typical applications and services of a smart city. Tangible results are expected to influence the definition and specification of Future Internet architecture design from viewpoints of Internet of Things and Internet of Services. The facility comprises a large number of Internet of Things devices deployed in several urban scenarios which will be federated into a single testbed. In this paper the deployment being carried out at the main location, namely Santander city, is described. Besides presenting the current deployment, in this article the main insights in terms of the architectural design of a large-scale IoT testbed are presented as well. Furthermore, solutions adopted for implementation of the different components addressing the required testbed functionalities are also sketched out. The IoT experimentation facility described in this paper is conceived to provide a suitable platform for large scale experimentation and evaluation of IoT concepts under real-life conditions.This work is funded by research project SmartSantander, under FP7-ICT-2009-5 of the 7th Framework Programme of the European Community. Authors would like to acknowledge the collaboration with the rest of partners within the consortium leading to the results presented in this paper

    Spatiotemporal progression of ubiquitin-proteasome system inhibition after status epilepticus suggests protective adaptation against hippocampal injury.

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    BACKGROUND: The ubiquitin-proteasome-system (UPS) is the major intracellular pathway leading to the degradation of unwanted and/or misfolded soluble proteins. This includes proteins regulating cellular survival, synaptic plasticity and neurotransmitter signaling; processes controlling excitability thresholds that are altered by epileptogenic insults. Dysfunction of the UPS has been reported to occur in a brain region- and cell-specific manner and contribute to disease progression in acute and chronic brain diseases. Prolonged seizures, status epilepticus, may alter UPS function but there has been no systematic attempt to map when and where this occurs in vivo or to determine the consequences of proteasome inhibition on seizure-induced brain injury. METHOD: To determine whether seizures lead to an impairment of the UPS, we used a mouse model of status epilepticus whereby seizures are triggered by an intra-amygdala injection of kainic acid. Status epilepticus in this model causes cell death in selected brain areas, in particular the ipsilateral CA3 subfield of the hippocampus, and the development of epilepsy after a short latent period. To monitor seizure-induced dysfunction of the UPS we used a UPS inhibition reporter mouse expressing the ubiquitin fusion degradation substrate ubiquitin(G76V)-green fluorescent protein. Treatment with the specific proteasome inhibitor epoxomicin was used to establish the impact of proteasome inhibition on seizure-induced pathology. RESULTS AND CONCLUSIONS: Our studies show that status epilepticus induced by intra-amygdala kainic acid causes select spatio-temporal UPS inhibition which is most evident in damage-resistant regions of the hippocampus, including CA1 pyramidal and dentate granule neurons then appears later in astrocytes. In support of this exerting a beneficial effect, injection of mice with the proteasome inhibitor epoxomicin protected the normally vulnerable hippocampal CA3 subfield from seizure-induced neuronal death in the model. These studies reveal brain region- and cell-specific UPS impairment occurs after seizures and suggest UPS inhibition can protect against seizure-induced brain damage. Identifying networks or pathways regulated through the proteasome after seizures may yield novel target genes for the treatment of seizure-induced cell death and possibly epilepsy

    Desafíos de las metrópolis: Efectos ambientales y sociales. Tendencias geográficas II

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    El libro está conformado de estudios realizados por profesores-investigadores de la Universidad Autónoma del Estado de México, de la Universidad de Varsovia, así como de la Universidad Pedagógica Comisión de Educación Nacional de Cracovia. En esta obra se exponen algunas investigaciones sobre los cambios en los factores sociales, naturales, económicos y ambientales como principales desafios que presentan las zonas de México, Polonia y de contextos de Sudamérica, tales como Sao Paulo, Quito y Bogotá y ciudades medias y pequeñas.Universidad Autónoma del Estado de Méxic

    Enfrentando los riesgos socionaturales

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    El objetivo del libro es comprender la magnitud de los Riesgos Socionaturales en México y Latinoamérica, para comprender el peligro que existe por algún tipo de desastre, ya sea inundaciones, sismos, remoción en masa, entre otros, además conocer qué medidas preventivas, correctivas y de contingencias existen para estar atentos ante alguna señal que la naturaleza esté enviando y así evitar alguna catástrofe. El libro se enfoca en los aspectos básicos de análisis de los peligros, escenarios de riesgo, vulnerabilidad y resiliencia, importantes para la gestión prospectiva o preventiva
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