Architecture of white-rumped swallow’s (<i>Tachycineta leucorrhoa</i>) nests built in nest boxes

La arquitectura de los nidos de la Golondrina Ceja Blanca (<i>Tachycineta leucorrhoa</i>) no ha sido descripta en detalle hasta el momento y posiblemente varíe con las dimensiones de la cavidad en la cual son construidos. Se describen las etapas de la construcción, la arquitectura y los elementos que componen los nidos de esta especie en cajas nido de iguales dimensiones. Las golondrinas ocuparon el 25% de la altura de la caja y construyeron la copa en el centro del espacio disponible (donde el aislamiento térmico de la temperatura externa es mayor) y nunca cerca de la entrada (donde el riesgo de predación es mayor). A medida que avanzó la temporada reproductiva, las golondrinas redujeron el tiempo de construcción de la base, iniciaron la puesta de los huevos con un número menor de plumas acolchando la copa y terminaron el nido más rápidamente; el número final de plumas en la copa y corona, sin embargo, fue mayor. No se encontró relación entre el éxito de los nidos y el avance de la temporada reproductiva o la composición de los nidos. Se compararon estos nidos con los que construye la Golondrina Bicolor (<i>Tachycineta bicolor</i>) en el Hemisferio Norte.The architecture of White-rumped Swallow´s (<i>Tachycineta leucorrhoa</i>) nests has not been described yet, and probably varies along with the cavity in which they are built. We describe the stages of nest construction, their architecture and components at nests built in nest-boxes of equal dimensions. White-rumped Swallow used 25% of the available height to build the nest, and placed the nest cup in the center of the box (where maximum thermal isolation from external temperature is expected) and never on the wall close to the box entrance (where the risk of predation is maximum). As the breeding season progressed, swallows built the mat of dried grass faster, began to lay eggs with fewer feathers lining the cup, and completed the nest in fewer days. In spite of this, the number of feathers in the cup and crown (the area outside the cup on top of nest material) was higher at the end of the breeding season than at the beginning. We found no relationship between nesting success and the time of the breeding season or the composition of the nest. We compared the nests built by White-rumped Swallows with those of Tree Swallows (<i>Tachycineta bicolor</i>) from the Northern Hemisphere

Good Reasons and Guidance for Mapping Planktonic Protist Distributions

Analysing the spatio-temporal distribution of protistan microplankton has faced both conceptual and technical difficulties. However, recognition of a need to study planktonic patchiness, application of a major geology-based methodology (geostatistics) to ecology, and advances in computational technologies have widened the interest in this topic and made it more assessable. This review provides methodological and conceptual guidance on the application of geostatistics to microplankton analysis, using ciliates as example model organisms. Applying geostatistical analysis (and complementary methodologies) to the distribution of ciliate and phytoplankton reveals that attributes of their populations and assemblages (e.g. abundance, biomass, production, diversity) are patchily distributed at multiple spatial-scales in different aquatic environments, and these change over time. Data examined from several environments and scales exhibit distinct patterns of patches regarding their shape, density, and structure; these data can then be used to suggest a behavioural niche-separation of ciliates and the influence of patchiness on the rate processes of food webs. Throughout the review, basic guidance is provided for interpreting where, when, and why planktonic ciliate are so distributed, and directions for work on patchiness is offered, including a guide to the main literature on the topic. This should, therefore, be a useful stepping-stone for researchers interested in the impact of patchiness on protistan ecology, regardless of the environment

Federalismo fiscal. Unión nacional. Ingresos brutos y convenio multilateral. Coparticipación federal. Sucinta reflexión

La República Argentina es un país de gran extensión, con manifiestas particularidades y/o desniveles de diverso orden en lo interno, por lo cual le ha sido recomendable el régimen federal, que fuera sabiamente establecido en la Constitución Naciona (arts, 1, 4, 5, 9, 10, 11, 12, 26, 75 incs.1°, 2°, 12°, 13°, 18°, 19°, 30°, 121, 123, 125, 126, 129 y ccs. CN), no sin sangrientas dificultades originarias y evidentes falencias posteriores que continúan y aún se agravan , la cual enuncia seis objetivos en su Preámbulo, de los cuales –con alcance general, pero en particular para esta nota- enfatizo el primero

Impact Assessment Study on the Living Conditions of Women and Children, Haïti

In response to the earthquake that hit Haiti on 12 January 2010, Solidarités International (SI) provided urgent basic services of Water, Sanitation and Hygiene in over 52 Internally Displaced Peoples (IDP) Sites, and played a vital role in preventing the spread of the cholera outbreak in October of that same year and improving medical care for people affected by the epidemic and to reduce risks of further propagation. Solidarités International’s engagement has been further expanded to other programs, including assistance for the return of displaced communities to their original neighborhoods. The daily living conditions and responsibilities of women subject many of them and their children to risks during various phases of a disaster. Women and children are most at risk and suffer the greatest in disaster situations. The present article discusses the impacts of the disaster on women and children, and the impact of SI’s programs. It also aims to identify some of the response gaps and mistakes attributed to SI and other humanitarian actors due to the lack of gender sensitive approach.Suite au séisme qui a frappé Haiti le 12 janvier 2010, Solidarités International (SI) a mis en place des services d'urgence de base en matière d'eau, d'assainissement et d'hygiène dans plus de 52 sites de déplacés. L’association d’aide humanitaire a également joué un rôle primordial dans la prévention du choléra en octobre 2010 et dans l’amélioration des soins médicaux prodigués aux personnes touchées par l’épidémie, réduisant les risques de propagation de la maladie. Solidarités International a aussi lancé de nombreuses autres initiatives, notamment l’aide au retour des populations déplacées dans leurs quartiers d’origine. Les conditions de vie quotidiennes et les responsabilités des femmes exposent bon nombre d’entre elles et leurs enfants à divers risques au cours des différentes phases d’une catastrophe, les femmes et les enfants étant les sujets les plus à risque dans ce type de situation. Cet article examine l’impact du séisme sur les femmes et les enfants ainsi que les effets des programmes mis en place par SI. Il permet en outre d’identifier les insuffisances en termes d’actions et les erreurs attribuées à SI et aux autres acteurs de l’humanitaire en raison d’une absence d’approche sexospécifique.En respuesta al terremoto que azotó Haití el 12 de enero de 2010, la ONG francesa Solidarités International (SI) proporcionó servicios básicos urgentes de agua, instalaciones sanitarias e higiene en más de 52 campamentos para desplazados y jugó un importante papel en la prevención de la expansión del brote de cólera en octubre del mismo año, mejorando además los cuidados médicos de las personas afectadas por la epidemia para reducir los riegos de una mayor propagación. El compromiso de Solidarités International se ha extendido a otros programas, incluida la asistencia para el regreso de las comunidades desplazadas a sus barrios de origen. Las condiciones de vida y las responsabilidades cotidianas de las mujeres hacen que muchas de ellas y sus hijos sean más sensibles a los riesgos durante las diferentes fases de un desastre y que por ello sean los que más sufren. Este artículo habla del impacto de los desastres en mujeres y niños y del impacto de los programas de SI. También pretende identificar algunos de los vacíos y errores atribuidos a SI y a otros agentes humanitarios debidos a la falta de un enfoque que tome en consideración el género

Patrones de diversidad de ciliados del plancton en la laguna de Chautengo, Guerrero, México

The study of the spatial distribution of plankton diversity is important, as it contributes to gain insight about ecosystems structure and functioning. We studied the spatial organization of planktonic ciliate diversity in Chautengo lagoon, Guerrero. The objectives were 1) to identify and characterize the spatial patterns of ciliate diversity and their seasonal variability, and 2) to assess the influence of environmental factors on diversity distribution. Conditional simulation geostatistical analysis was applied to H (Shannon diversity index), computed from samples collected in 40-45 sites in the lagoon in rainy and dry seasons. The relationship between ciliate diversity and lagoonal environment was examined using principal component analysis (PCA). We identified 36 planktonic ciliate morphospecies; H ranged from 0.08 to 1.9 and was patchily distributed. PCA indicated that ciliate diversity changed according to the seasons and the hydrodynamics of the sand bar opening and closing. In the rainy season, when the sand bar was open, a higher spatial heterogeneity was prevalent, with many smaller patches (1.6 km) dominated by the phototrophic Myrionecta rubra. In contrast, during the dry season and when the sand bar was closed, two larger diversity patches (2.7 km) prevailed and the dominant ciliates were Lohmanniella oviformis and Tintinnopsis sp. The impact of the patchily distributed ciliate diversity on the food webs is discussed.El estudio de la distribución espacial de la diversidad del plancton contribuye al conocimiento de la estructura y el funcionamiento de los ecosistemas. Se estudió la organización espacial de la diversidad de ciliados del plancton en la laguna de Chautengo, Guerrero, con los objetivos de: 1) identificar y caracterizar los patrones espaciales de diversidad de ciliados y su variación estacional, y 2) evaluar la influencia de factores ambientales sobre la diversidad. Se aplicó un análisis geoestadístico de simulación condicional a los valores de H (índice de diversidad de Shannon), calculados a partir de muestras recolectadas en 40-45 sitios de la laguna durante las épocas de lluvias y de secas. Las interrelaciones entre la diversidad de ciliados y el ambiente lagunar se evaluaron usando un análisis de componentes principales (ACP). Se identificaron 36 morfoespecies de ciliados pláncticos; H varió entre 0.08 y 1.9 y se distribuyó en manchones. El ACP indica que la diversidad de ciliados cambió estacionalmente y en función de las características hidrodinámicas derivadas de la apertura y cierre de la boca lagunar. Durante la temporada de lluvias y cuando la barra estuvo abierta, se presentó una mayor heterogeneidad espacial con numerosos manchones de diversidad de menor extensión (1.6 km), en los cuales dominó el ciliado fototrófico Myrionecta rubra. En contraste, en temporada de secas y cuando la boca de la laguna permaneció cerrada, se encontraron dos manchones de diversidad de mayor tamaño (2.7 km), en los que dominaron Lohmanniella oviformis y Tintinnopsis sp. Se discute el impacto sobre las redes tróficas de la distribución en manchones de la diversidad de ciliados

Insights on Short-term Blooms of Planktonic Ciliates, Provided by an Easily Recognised Genus: Cyrtostrombidium

Planktonic ciliates occasionally form brief rapid increases in numbers (blooms) that can be trophically important. Although model simulations and mesocosm studies indicate that blooms occur over 10 to 20 days, field data are rarely suffi ciently detailed to reveal their occurrence and demise. Our data (collected over 57 weeks across a coastal lagoon) offer insights into the population dynamics of a single species, place these in the context of the entire ciliate assemblage, and provide guidance on what should continue to be examined. Specifically, to evaluate population dynamics we examine two species of Cyrtostrombidium, characterise temporal and spatial variation of their abundance, and relate these to abiotic phenomena and biological factors. This is also the first report of Cyrtostrombidium in a tropical coastal lagoon. Collectively our analysis reveals key aspects of the dynamics of this genus: 1) small-scale peaks in abundance are ~30 m in size and can persist for ~10–30 days, reaching a maximum of 100 cells ml–1; 2) these increases are driven by biotic factors (revealed through autocorrelation analysis); 3) long-term trends are driven by the shift between dry and rainy seasons and by the periods of isolation of lagoon from the sea (revealed through multiple regression analysis); 4) blooms may at times control primary production; 5) conjugation, an ecologically important event, may be associated with blooms (at times 9% of population was conjugating); and 6) dinoflagellate parasitism, poorly described in oligotrichs, is potentially important in population demise. These results both reflect on how ciliates may behave in short-term events and should encourage the continued need for detailed observations of field samples at a high taxonomic resolution

Modelling of a radio frequency plasma bridge neutralizer (RFPBN)

A performance model of a radio frequency plasma bridge neutralizer was developed to calculate the electrical parameters and optimize the neutralizer design. Minimization of power losses and gas consumption, and a maximization of the neutralizer lifetime and the reliability of the system are requirements of all electric propulsion concepts and strongly determine their future application. The requirements of the neutralizer depend on mission profiles

La importancia del vanadio en los seres vivos

Abstract (The importance of vanadium in living organisms)The discovery of high vanadium concentrations in living organisms and the constant development of bioinorganic chemistry have promoted the interest in understanding the biological role of this metal and its possible applications in medicinal inorganic chemistry. The design of new metal-based drugs depends largely on the physicochemical properties of the metallic center under physiological conditions. In this paper we present a short review on the biological role of vanadium and its function as an active center in certain enzymes, as well as the state-of-the-art of vanadium-based drugs with antifungical, anticarcinogenic and antiobesity properties.ResumenEl descubrimiento de organismos con concentraciones de vanadio superiores a las normales, aunado al desarrollo de la química bioinorgánica, ha despertado interés por entender a fondo las funciones biológicas que este elemento pueda desempeñar y las posibles aplicaciones que los compuestos de coordinación con dicho metal puedan tener en farmacología. El diseño de fármacos basados en metales depende, en gran parte, de las propiedades farmacológicas del centro metálico en el organismo. En este artículo se presenta una breve revisión sobre algunas funciones biológicas del vanadio y su papel en el centro activo de enzimas, así como las últimas investigaciones enfocadas al desarrollo de fármacos basados en vanadio con actividad antifúngica, anticancerígena y antiobesidad

Prevention and control of cholera with household and community water, sanitation and hygiene (WASH) interventions: A scoping review of current international guidelines.

INTRODUCTION: Cholera remains a frequent cause of outbreaks globally, particularly in areas with inadequate water, sanitation and hygiene (WASH) services. Cholera is spread through faecal-oral routes, and studies demonstrate that ingestion of Vibrio cholerae occurs from consuming contaminated food and water, contact with cholera cases and transmission from contaminated environmental point sources. WASH guidelines recommending interventions for the prevention and control of cholera are numerous and vary considerably in their recommendations. To date, there has been no review of practice guidelines used in cholera prevention and control programmes. METHODS: We systematically searched international agency websites to identify WASH intervention guidelines used in cholera programmes in endemic and epidemic settings. Recommendations listed in the guidelines were extracted, categorised and analysed. Analysis was based on consistency, concordance and recommendations were classified on the basis of whether the interventions targeted within-household or community-level transmission. RESULTS: Eight international guidelines were included in this review: three by non-governmental organisations (NGOs), one from a non-profit organisation (NPO), three from multilateral organisations and one from a research institution. There were 95 distinct recommendations identified, and concordance among guidelines was poor to fair. All categories of WASH interventions were featured in the guidelines. The majority of recommendations targeted community-level transmission (45%), 35% targeted within-household transmission and 20% both. CONCLUSIONS: Recent evidence suggests that interventions for effective cholera control and response to epidemics should focus on case-centred approaches and within-household transmission. Guidelines did consistently propose interventions targeting transmission within households. However, the majority of recommendations listed in guidelines targeted community-level transmission and tended to be more focused on preventing contamination of the environment by cases or recurrent outbreaks, and the level of service required to interrupt community-level transmission was often not specified. The guidelines in current use were varied and interpretation may be difficult when conflicting recommendations are provided. Future editions of guidelines should reflect on the inclusion of evidence-based approaches, cholera transmission models and resource-efficient strategies