873 research outputs found
Young and very young stars in NGC 3372, the Carina nebula
Results are presented of a large-scale imaging photometric study of the stellar population in the northern part of NGC 3372 with a w avelength co verage from 0.33 to 2.5 µm. All observations were made at Las Campanas Observatory . The sizes of the three stellar clusters, Tr 14, Tr 15 and Tr 16, were determined b y means of star counts. Two-colour and colour-magnitude diagrams are presented and analyzed for eac h individual cluster. The three clusters were found to b e at a similar distance from the Sun, = 2 . 7 kpc, but with very large scatter in both A V and d . suggesting drastic variations in intracluster dust densit y . Dust particle size distribution variations are eviden t resulting in wide variations in extinction law. We determined ages bet ween 3 and 60 million years for Tr 15 and bet ween less than 1 and 6 million years for Tr 14 and Tr 16. The Tr 14 cluster is partially em bedded in a dense molecular cloud that extends to wards the south west reaching its highest densit y some three arcmin from the cluster nucleus. The ric h UV field created b y the Tr14 stars ionizes most of the visible HI I region in its vicinit y and most of the radio HI I region Car I. Deep J H K images of the Car I region reveal the presence of a young, em bedded stellar population that includes several O9–B0 stars and an ultracompact HI I region.Fil: Tapia, M.. Universidad Nacional Autónoma de México; MéxicoFil: Roth, M.. Las Campanas Observatory; ChileFil: Vazquez, Ruben Angel. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - La Plata. Instituto de AstrofÃsica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y GeofÃsicas. Instituto de AstrofÃsica la Plata; ArgentinaFil: Persi, P.. IASFC, CNR; Itali
Buturi Solar
The village of Makongoro in the Buturi community of Tanzania lacks the resources to bring any form of energy to power the local school. The most reliable source of energy we could bring to the school is in the form of a photovoltaic system, as the climate of Buturi provides an ideal location for the implementation of such system. We have designed a solar microgrid specifically for Buturi and the needs of the school, that has the capability to power laptops, cell phones, and lighting throughout the school building. The system is fully detailed and explained in this report, with the final goal of implementation in the near future
Análisis del comportamiento hidráulico del fenómeno de golpe de ariete en el sistema de abastecimiento de agua Vilcanota de la ciudad de Cusco
El presente trabajo de investigación, previo un extenso trabajo de recopilación de información, realiza el análisis del comportamiento hidráulico del fenómeno del golpe de ariete en el sistema de abastecimiento de agua Vilcanota de la ciudad del Cusco, la cual ha cumplido su periodo, diseño y vida útil, por lo tanto los equipos y/o dispositivos de protección antiariete de cada estación de bombeo no protegerÃan adecuadamente cada estación de bombeo (apagado de bombas y/o corte de energÃa) cuando estos operen al 100% de su capacidad de producción de agua dejando a la ciudad del Cusco desabastecida de este recurso hÃdrico. Para tal motivo, se ha planteado realizar el análisis descriptivo de los parámetros hidráulicos que gobiernan el comportamiento hidráulico del golpe de ariete en condiciones máximas y actuales de explotación mediante la simulación hidráulica con los softwares: Bentley OpenFlows WaterGEMS - Water Distribution Analysis and Design y Bentley HAMMER Connect Edition, y mediciones del transitorio hidráulico en las estaciones de bombeo de Rumicolca y Collan
CaracterÃsticas da indústria paulista nos anos 90: em direção a uma city region?
A literatura internacional que discute as transformações provocadas pela globalização econômica, difusão das novas tecnologias da informação sobre paÃses, territórios e empresas tem apresentado algumas hipóteses que sustentam a emergência de novas configurações econômicas e territoriais chamadas ora de global city ora de city region. Elas refletem uma nova dinâmica baseada em redes de atores envolvidos em intensos fluxos de conhecimento e tecnologia e em uma progressiva capacidade de aprendizado institucional. Neste trabalho discutimos essas hipóteses à luz da experiência da economia paulista, procurando pensar a possibilidade ou não de assimilar o processo de reconcentração ampliada aos conceitos de global city e city region. Além dos enfoques mencionados, examinamos e apoiamo-nos, em termos teóricos, nas proposições dos autores filiados à escola regulacionista. A partir da leitura crÃtica dessas correntes, desenvolvemos a concepção de que, justamente devido à s mudanças ocorridas na economia do estado de São Paulo nos anos noventa, houve um reforço da concentração espacial da indústria, a qual, embora apresente alguns aspectos associados à s configurações econômicas espaciais denominadas de city regions, têm marcadas e importantes diferenças. Por isso, esse movimento de concentração ampliada, marcado pela forte predominância da região metropolitana de São Paulo (aà incluÃda a região do ABC) e as regiões que compõem o seu entorno (Campinas, São José dos Campos, Santos e Sorocaba), não pode ser caracterizado como uma dinâmica regional conectada com redes de cidades globais e desarticulada do restante da economia brasileira. Também, diferentemente do que afirma a literatura internacional que discute a emergência das cidades globais, não associamos as mudanças mencionadas a uma virtual substituição do setor secundário pelo terciário.
Abstract
International literature discussing the transformation of countries, territories and firms brought about by economic globalization and the dissemination of new information technologies has presented some hypotheses that maintain the emergence of new economic and territorial configurations known as «global cities» or «city regions». The latter reflect a new dynamic based on networks of actors involved in intense flows of knowledge and technology, as well as increased abilities for institutional learning. In this paper we discuss such hypotheses in light of experiences in the São Paulo state economy, considering whether processes of «expanded reconcentration» can be accommodated within the concepts of global city and city region. In addition to the mentioned perspectives, we also examine and take support, in theoretical terms, from the propositions of authors affiliated with the regulationist school. Through a critical reading of these currents, we develop the notion that, precisely due to changes occurring in the economy of the state of São Paulo during the nineties, there was a spatial concentration of industry which, although demonstrating some aspects associated with the economic spatial configurations known as city regions, has noticeable and significant differences. For this reason, this movement of «expanded reconcentration», marked by the heavy predominance of the Greater São Paulo (including therein the region known as the ABC) and surrounding regions (Campinas, São José dos Campos, Santos e Sorocaba) cannot be characterized as a regional dynamic connected with networks of global cities and disconnected from the rest of the Brazilian economy. Furthermore, unlike the international literature that discusses the emergence of global cities, we cannot associate the mentioned changes with a virtual substitution of the secondary sector by the service sector.
Résumé
La littérature internationale portant sur les transformations générées aussi bien par la mondialisation économique que la diffusion des nouvelles technologies de l'information sur les pays, les territoires et les entreprises, soulève quelques hypothèses qui soutiennent l'émergence des nouvelles configurations économiques et territoriales désignées tantôt global city, tantôt city region. Elles réflètent une nouvelle dynamisation basée sur des réseaux d'acteurs engagés dans d'intenses flux de connaissances et technologie et dans une progressive capacité d'apprentissage institutionnelle. Dans notre travail, nous aborderons ces hypothèses à la lumière de l'expérience de l'économie de São Paulo et réfléchisserons aux possibilités d'assimiler les processus de reconcentration élargies aux concepts de global city et city region. Outre ces priorités, nous examinerons et soutiendrons, sur le plan théorique, les propositions des auteurs associés à l'école de la régulation. À partir de la lecture critique de ces courants, nous présenterons l'idée selon laquelle en raison des changements survenus dans l'économie de l'état de São Paulo dans les années 90, un effort de concentration spaciale des usines s'est produit. Bien que celles-ci aient quelques caractéristiques qu'on peut associer aux configurations économiques spaciales appelées city regions, elles présentent de nettes et importantes différences. Aussi ce mouvement de concentration élargie, caractérisé par l'importance de la région métropolitaine de São Paulo (y compris la région de l'ABC) et les régions composant ses alentours (Campinas, São José dos Campos, Santos e Sorocaba), ne peutil être caractérisé comme un mouvement régional en contact avec les réseaux des villes globales et coupée du reste de l'économie brésilienne. Contrairement à ce qu'affirme la littérature internationale discutant de l'émergence des villes globales, nous n'associons pas ces changements à un virtuel remplacement du secteur secondaire par celui du tertiaire
Choline [amino acid] ionic liquid/water mixtures: A triple effect for the degradation of an organophosphorus pesticide
A series of ionic liquids (ILs) composed by choline (Ch) as a cation and different amino acids (AA) as anions and their respective aqueous mixtures were prepared using different [Ch][AA] contents in a range of 0.4-46 mol % IL. These solvents were used for the first time to achieve an eco-friendlier Paraoxon degradation. The results show that [Ch][AA]/water mixtures are an effective reaction medium to degrade Paraoxon, even when the IL content in the mixture is low (0.4 mol % IL) and without the need of an extra nucleophile. Both the kinetics and the degradation pathways of pesticides depend on the nature of the AA on [Ch][AA] and the amount of an IL present in the mixture. We have demonstrated that in those mixtures with a low amount of [Ch][AA], the hydrolysis reaction is the main pathway for Paraoxon degradation, showing a catalytic effect of the IL. However, as the percentage of [Ch][AA] increases in the mixture, the nucleophilic attack of [Ch][AA] is evident. Finally, the aim of this study was to provide evidence of a promising and biocompatible methodology to degrade a toxic compound (Paraoxon) using a minimal quantity of an IL designed totally from natural resources.Fil: Pavez, Paulina. Universidad Católica de Chile; ChileFil: Figueroa, Roberto. Universidad Católica de Chile; ChileFil: Medina, Mayte. Universidad Católica de Chile; ChileFil: Millán, Daniela Andrea. Universidad Bernardo O’Higgins. Centro Integrativo de BiologÃa y QuÃmica Aplicada; ChileFil: Falcone, Ruben Dario. Universidad Nacional de RÃo Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de RÃo Cuarto. Facultad de Ciencias Exactas FisicoquÃmicas y Naturales. Departamento de QuÃmica; ArgentinaFil: Tapia, Ricardo. Universidad Católica de Chile; Chil
Disease caused by Yersinia ruckeri serotype O2b found in Chilean-farmed coho salmon, Oncorhynchus kisutch (Walbaum, 1792)
ArtÃculo que describe Yersiniosis por Yersinia ruckeri serotype O2b en salmones de Chile.During September and October 2015, farmed coho salmon (Oncorhynchus kisutch [Walbaum, 1792]) suffered outbreak mortalities. For all outbreaks, cumulative losses of the affected population reached up to 15%. Three representative bacterial isolates were recovered with the objective of antigenically identifying and characterizing the causative microorganism of the ERM outbreaks in Chilean coho salmon. The obtained micro-organisms were characterized as Y. ruckeri O2b, making this the first report of a mortality-associated isolate in coho salmon farmed in Chile.Work was supported by the Grants CONICYT/ FONDAP/15110027 and FONDECYT No 1150695, awarded by the Comisión Nacional de Investigación CientÃfica y Tecnológica (CONICYT, Chile)
PolÃtica de serviço universal e liberalização das telecomunicações: a experiência brasileira no contexto de uma agenda de transição
The goal of this paper is to analyze the issue of Universal Service
under the light of these processes of structural changes and the appraisal
of the content of Universal Service itself, in particular the Brazilian
experience, especially the case of São Paulo. The exam of perspectives
of universalization of telecommunication services in Brazil will take into
account three kind of factors: (a) the context of institutional changes
recently associated to the rise of a new model of regulation and competition
in the telecommunication sector; (b) characteristics of the strategy of
privatization of Brazilian system, especially in what concerns the concept
of universal services; (c) the socioeconomic characteristics of Brazilian
society, especially in the State of São Paulo.The goal of this paper is to analyze the issue of Universal Service
under the light of these processes of structural changes and the appraisal
of the content of Universal Service itself, in particular the Brazilian
experience, especially the case of São Paulo. The exam of perspectives
of universalization of telecommunication services in Brazil will take into
account three kind of factors: (a) the context of institutional changes
recently associated to the rise of a new model of regulation and competition
in the telecommunication sector; (b) characteristics of the strategy of
privatization of Brazilian system, especially in what concerns the concept
of universal services; (c) the socioeconomic characteristics of Brazilian
society, especially in the State of São Paulo
Development of mental health first aid guidelines for problem drinking: a Delphi expert consensus study in Argentina and Chile
BACKGROUND: Among all psychoactive substances, alcohol consumption presents the most significant public health problem and is a leading risk factor for overall disease burden in Latin America. However, most people who meet criteria for a substance use disorder do not receive treatment in primary or secondary care sources. Community members can play a role in helping people to seek help as they are likely to encounter people experiencing problem drinking and recognize the signs. However, many do not have adequate mental health first aid knowledge or skills to provide help. We aimed to culturally adapt the existing English-language mental health first aid guidelines for helping someone with problem drinking for Argentina and Chile. METHODS: The Delphi consensus method was used to determine the importance of helping actions translated from the English-language guidelines and to add new actions suggested by expert panellists. The importance of each statement was rated by two expert panels. Panel one included people with lived experience (either their own or as a support person, n = 23) recruited in Argentina and panel two included health professionals (n = 31) recruited in Argentina and Chile. RESULTS: Overall, 165 helping actions were endorsed by panellists across two consecutive survey rounds. Endorsed items included 132 of the 182 items translated into Spanish from the English-language guidelines and 33 of the 61 new items generated from panellists' comments in the first survey round. CONCLUSIONS: While there were some similarities in recommended helping actions between English-speaking countries, and Argentina and Chile, key differences were seen in attitudes to low-risk drinking. While there was a relatively high level of agreement between health professionals and people with lived experience, some divergence of opinion was seen, particularly in the area of commitment to recovery as a condition for help. Future research should explore the implementation of the guidelines
DESARROLLO DE UNA ESTRATEGIA DE MODULACION BASADO EN CONTROL PREDICTIVO APLICADO EN SISTEMAS CONECTADOS A LA RED ELÉCTRICA (DEVELOPMENT OF A MODULATION STRATEGY BASED ON PREDICTIVE CONTROL APPLIED TO GRID-CONNECTED SYSTEM)
Resumen
Se presenta una estrategia de modulación basada en técnicas de control predictivo, la cual es implementada en un inversor monofásico sin transformador en modo común conectado a la red eléctrica; dicha estrategia, se conforma de un algoritmo que actúa de acuerdo con la toma de decisiones basadas en la comparación de las señales de referencia y la respuesta completa del sistema. Se pretende obtener una intensidad de corriente de salida que se encuentre con el mismo ángulo de fase con la tensión de la red ante cambios de carga resistiva y de valores de referencia. Por otra parte, se desea que esta modulación sea igualmente efectiva ante cargas reactivas no lineales.
Palabras Clave: Carga resistiva, Control predictivo, Inversor monofásico sin transformador, Respuesta completa.
Abstract
A modulation strategy based in predictive control techniques is presented, which is implemented in a Transformerless Common-Mode Current-Source Inverter Grid-Connected. The strategy is conformed by an algorithm that responds according to the decision making between reference signals and the complete response of the system. This work seeks to obtain an output signal of current in the same phase than the voltage grid which responds on resistive loads and reference values changes. Finally, it is desired to obtain same performance. Even with non-lineal reactive loads.
Keywords: Complete response, Predictive control, resistive load, Transformerless Single Phase Inverter
First identification and characterization of Streptococcus iniae obtained from tilapia (Oreochromis aureus) farmed in Mexico
Estudio de cuadros septicémicos por Streptococcus iniae en tilapias de cultivo de México.This is the first study to isolate, identify and characterize Streptococcus iniae as the
causative disease agent in two tilapia (Oreochromis aureus) populations. The populations
were geographically isolated, of distinct origins, and did not share water
sources. Affected fish showed various external (e.g., exophthalmia and cachexia,
among others) and internal (e.g., granulomatous septicaemia and interstitial nephritis,
among others) signs. All internal organ samples produced pure cultures, two of
which (one from each farm, termed S-1 and S-2) were subjected to biochemical,
PCR and 16S rRNA sequencing (99.5% similarity) analyses, confirming S. iniae identification.
The two isolates presented genetic homogeneity regardless of technique
(i.e., RAPD, REP-PCR and ERIC-PCR analyses). Pathogenic potentials were assessed
through intraperitoneal injection challenges in rainbow trout (Oncorhynchus mykiss)
and zebrafish (Danio rerio). Rainbow trout mortalities were respectively 40% and
70% at 104 and 106 CFU per fish with the S-1 isolate, while 100% mortality rates
were recorded in zebrafish at 102 and 104 CFU per fish with the S-2 isolate. The
obtained data clearly indicate a relationship between intensified aquaculture activities
in Mexico and new disease appearances. Future studies should establish clinical
significances for the tilapia industry.Universidad Autónoma del Estado de México, Grant/Award Number: 3675/2014/CID and 4489/2018/CI. Comisión Nacional de Investigación CientÃfica y Tecnológica, Grant/Award Number: FONDAP 15110027, FONDECYT 115069
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