Redes y análisis organizacional: roles, posiciones y poder de fragmentación de las relaciones sociales y comerciales

En un Estudio de caso, con la "Sociedad Cooperativa de Productores y Lombricultores de San Pedro Tlapacoyán, Veracruz, México", se observo que uno de los problemas es la actitud y las relaciones inter organizacionales de los productores. A través de indicadores de rede sociales, se analizaron lo roles que juega cada actor, su posición dentro de la red de relaciones y las relaciones con mayor poder de fragmentación. Los resultados indican que la importancia de un actor está más en función de su posición en la red que del número de relaciones que presenta cada integrante del grupo de productores. Se encontró que cada actor juega diferentes roles en función de sus intereses individuales y que las relaciones sociales presentan mayor poder de fragmentación sobre las relaciones comerciales

Role of the vaccum pressure and temperature in the shape of metal Zn nanoparticles

Artículo especializado en revista indexadaZinc (Zn) nanoparticles were fabricated by the high-vacuum thermal evapouration technique. The vacuum pressure was modified from 10−6 to 15 Torr and the substrate temperature was increased from room temperature to 100◦C in order to evaluate the changes in the morphological and structural characteristics of the Zn nanoparticles. Well-faceted hexagonal disk shaped nanoparticles were formed at a vacuum pressure of 10−6 Torr with the substrate kept at room temperature. Aggregation and surface irregularities at the edges of the hexagonal nanodisks were observed with further increases in the vacuum pressure. The nanoscale characteristics of the nanodisks were lost at a vacuum pressure of 10−6 Torr and heating the substrate at 100◦C. The nanodisks were transformed into Zn wires at a vacuum pressure of 15 Torr with a substrate temperature of 100◦C. It is suggested that the initial stages of the growth of the Zn wires are governed by the agglomeration of the Zn nanodisks since the structure of the wires was observed to be composed by stacked nanodisks.CONACYT and PRODEP proyecto de red 2014-201

Com o diabo no corpo: os terríveis papagaios do Brasil colônia

Desde a Antiguidade, papagaios, periquitos e afins (Psittacidae) fascinaram os europeus por seu vivo colorido e uma notável capacidade de interação com seres humanos. A descoberta do Novo Mundo nada faria além de acrescentar novos elementos ao tráfico de animais exóticos há muito estabelecido pelos europeus com a África e o Oriente. Sem possuir grandes mamíferos, a América tropical participaria desse comércio com o que tinha de mais atrativo, essencialmente felinos, primatas e aves - em particular os papagaios, os quais eram embarcados em bom número. Contudo, a julgar pelos documentos do Brasil colônia, esses voláteis podiam inspirar muito pouca simpatia, pois nenhum outro animal - exceto as formigas - foi tantas vezes mencionado como praga para a agricultura. Além disso, alguns psitácidas mostravam-se tão loquazes que inspiravam a séria desconfiança de serem animais demoníacos ou possessos, pois só três classes de entidades - anjos, homens e demônios - possuíam o dom da palavra. Nos dias de hoje, vários representantes dos Psittacidae ainda constituem uma ameaça para a agricultura, enquanto os indivíduos muito faladores continuam despertando a suspeita de estarem possuídos pelo demônio. Transcendendo a mera curiosidade, essa crença exemplifica o quão intrincadas podem ser as relações do homem com o chamado “mundo natural”, revelando um universo mais amplo e multifacetado do que se poderia supor a princípio. Nesse sentido, a existência de aves capazes de falar torna essa relação ainda mais complexa e evidencia que as dificuldades de estabelecer o limite entre o animal e o humano se estendem além dos primatas e envolvem as mais inusitadas espécies zoológicas.Since ancient times, parrots and their allies (Psittacidae) have fascinated Europeans by their striking colors and notable ability to interact with human beings. The discovery of the New World added new species to the international exotic animal trade, which for many centuries had brought beasts to Europe from Africa and the Orient. Lacking large mammals, tropical America participated in this trade with its most appealing species, essentially felines, primates and birds - especially parrots - which were shipped in large numbers. It should be noted, however, that at times these birds were not well liked. In fact, according to documents from colonial Brazil, only the ants rank higher than parrots as the animals most often mentioned as agricultural pests. On the other hand, some of these birds were so chatty that people suspected them to be demonic or possessed animals, since only three classes of beings - angels, men and demons - have the ability to speak. Nowadays, several Psittacidae still constitute a threat to agriculture, and the suspicion that extremely talkative birds were demon possessed has also survived. More than a joke or a mere curiosity, this belief exemplifies how intricate man’s relationships with the “natural world” may be. In this sense, the existence of birds that are able to speak adds a further twist to these relationships, demonstrating that the problem of establishing a boundary between the animal and the human does not only involve primates, but also includes some unusual zoological species

Descomposition of ethane clatrhrates using different water-ethane models: molecular dynamics

El objetivo principal de este trabajo fue reproducir la transición de los clatratos de etano al pasar de un estado termodinámicamente estable a un estado termodinámicamente inestable a través de Dinámica Molecular. Se reprodujo el clatrato de etano en la simulación a partir de posiciones determinadas experimentalmente (difracción de rayos-x), la forma del clatrato es poliédrica y se denomina estructura I. Las primeras simulaciones se realizaron implementando 7 modelos de agua diferentes (SPC, SPC/E, TIP4P, TIP4P/ice, TIP4P/2005, TIP4Q). De acuerdo a los resultados el potencial SPC es el que tuvo mejor aproximación a la evidencia experimental, una alternativa que utilizamos fue modificar la metodología ajustando las reglas de combinación de Lorentz-Berthelot. Combinando tal modificación más los resultados obtenidos de los criterios de estabilidad (función de distribución radial, energía potencial, número de puentes de hidrógeno, número de coordinación, potencial de fuerza promedio y desplazamiento cuadrático promedio) se logró reproducir exitosamente la transición de fase de los clatratos de etano

Tópicos en termodinámica de procesos irreversibles y sistemas complejos

En este libro consideramos prudente expresar los resultados realizados en el contexto de temáticas específicas, de ahí el título del libro Tópicos en procesos irreversibles y sistemas complejos. Desarrollos que a corto, mediano y largo plazo tienen impacto en áreas prioritarias y de interés nacional e internacional. Ahora es efectivamente posible miniaturizar todo tipo de sistemas (por ejemplo: mecánicos, fluidos, electromecánicos o térmicos) en tamaños submicrométricos.Secretaría de Educación Pública-Subsecretaría de Educación Superior-Dirección General de Educación Superior Universitaria. Número del convenio con la Sep: 2017-15-001-017

Outcomes in Newly Diagnosed Atrial Fibrillation and History of Acute Coronary Syndromes: Insights from GARFIELD-AF

BACKGROUND: Many patients with atrial fibrillation have concomitant coronary artery disease with or without acute coronary syndromes and are in need of additional antithrombotic therapy. There are few data on the long-term clinical outcome of atrial fibrillation patients with a history of acute coronary syndrome. This is a 2-year study of atrial fibrillation patients with or without a history of acute coronary syndromes