Crecimiento de renovales de Drimys winteri después de 16 años de aplicados distintos tratamientos de raleo en las cordilleras de los andes y de la costa en Chile

Secondary Drimys winteri forests are among the most common and productive forests in south-central Chile. However, their management has been scarce or many times inadequate due to lack of silvicultural knowledge. In 1986 and 1990 three field experiments were installed; one in the Coastal range of the province of Ranco (40° 09' S) and two in the Andean range of the province of Llanquihue (41° 30' S), to evaluate the effects of different intensities of thinning on the growth and mortality of 28-year-old Drimys winteri secondary forests. After 16 and 10 years of evaluation, great differences were observed among treatments within and between the three experiments. In Hueicoya (Coastal Range) plots thinned at a distance of 3 m had the highest productivity. In Lenca A (Andean Range) the high mortality rates due to windfalls in the plots with trees spaced at 3 and 4 m caused the control plots to have the highest productivity rates. In Lenca B (Andean Range) plots thinned at 2.5 m distance between trees had no significant differences with control plots. At an equal thinning intensity the responses were very different among experiments. We discuss that site quality, residual composition, exposure to winds and rooting characteristics may have influenced these results. In general, it is recommended to thin at 25-45% residual densities (2-3 m distance between trees at the age of thinning of 9-12 cm quadratic stand diameter), but always depending on the risk of windfall

The Angular Clustering of WISE-Selected AGN: Different Haloes for Obscured and Unobscured AGN

We calculate the angular correlation function for a sample of 170,000 AGN extracted from the Wide-field Infrared Survey Explorer (WISE) catalog, selected to have red mid-IR colors (W1 - W2 > 0.8) and 4.6 micron flux densities brighter than 0.14 mJy). The sample is expected to be >90% reliable at identifying AGN, and to have a mean redshift of z=1.1. In total, the angular clustering of WISE-AGN is roughly similar to that of optical AGN. We cross-match these objects with the photometric SDSS catalog and distinguish obscured sources with (r - W2) > 6 from bluer, unobscured AGN. Obscured sources present a higher clustering signal than unobscured sources. Since the host galaxy morphologies of obscured AGN are not typical red sequence elliptical galaxies and show disks in many cases, it is unlikely that the increased clustering strength of the obscured population is driven by a host galaxy segregation bias. By using relatively complete redshift distributions from the COSMOS survey, we find obscured sources at mean redshift z=0.9 have a bias of b = 2.9 \pm 0.6 and are hosted in dark matter halos with a typical mass of log(M/M_odot)~13.5. In contrast, unobscured AGN at z~1.1 have a bias of b = 1.6 \pm 0.6 and inhabit halos of log(M/M_odot)~12.4. These findings suggest that obscured AGN inhabit denser environments than unobscured AGN, and are difficult to reconcile with the simplest AGN unification models, where obscuration is driven solely by orientation.Comment: Accepted for publication in ApJ. 13 pages, 15 figure

Using Machine Learning to Predict Swine Movements within a Regional Program to Improve Control of Infectious Diseases in the US.

Between-farm animal movement is one of the most important factors influencing the spread of infectious diseases in food animals, including in the US swine industry. Understanding the structural network of contacts in a food animal industry is prerequisite to planning for efficient production strategies and for effective disease control measures. Unfortunately, data regarding between-farm animal movements in the US are not systematically collected and thus, such information is often unavailable. In this paper, we develop a procedure to replicate the structure of a network, making use of partial data available, and subsequently use the model developed to predict animal movements among sites in 34 Minnesota counties. First, we summarized two networks of swine producing facilities in Minnesota, then we used a machine learning technique referred to as random forest, an ensemble of independent classification trees, to estimate the probability of pig movements between farms and/or markets sites located in two counties in Minnesota. The model was calibrated and tested by comparing predicted data and observed data in those two counties for which data were available. Finally, the model was used to predict animal movements in sites located across 34 Minnesota counties. Variables that were important in predicting pig movements included between-site distance, ownership, and production type of the sending and receiving farms and/or markets. Using a weighted-kernel approach to describe spatial variation in the centrality measures of the predicted network, we showed that the south-central region of the study area exhibited high aggregation of predicted pig movements. Our results show an overlap with the distribution of outbreaks of porcine reproductive and respiratory syndrome, which is believed to be transmitted, at least in part, though animal movements. While the correspondence of movements and disease is not a causal test, it suggests that the predicted network may approximate actual movements. Accordingly, the predictions provided here might help to design and implement control strategies in the region. Additionally, the methodology here may be used to estimate contact networks for other livestock systems when only incomplete information regarding animal movements is available

Accounting and international relations:Britain, Spain and the Asiento treaty

The boundaries between accounting and law are contingent on time–space intersections. Here, these margins are explored in the realm of international relations by focusing on the Asiento, an 18th century treaty granting Britain the monopoly to trade slaves with the Spanish American colonies. Although a relatively minor concern of treaty-makers, noncompliance with provisions of the Asiento by the South Sea Company placed accounting centre stage in conflicts between Britain and Spain. In combination with geo-strategic and domestic political circumstances, reporting failures exacerbated the commercial dispute between the two nations which culminated in war in 1739. The accounting provisions of the Asiento are examined by drawing on managerialist and realist theories of treaty compliance. It is shown that British noncompliance with accounting obligations under the treaty was driven by realist self-interest and the maximisation of material gain. Given that such motivations dominated behaviour attempts to manage noncompliance through the routine processes and structures of international politics proved unsuccessful. Managerial devices such as diplomatic exchanges over treaty ambiguity and securing greater informational transparency merely provided further opportunities for the pursuit of self-interest. It is suggested that divergent perceptions of the role of accounting in international relations stem from the unique political, legal, social and cultural configurations of nation states. The study highlights the limitations of accounting as an instrument of treaty verification. Its effectiveness in that capacity is diminished where there is no shared understanding of the significance, purpose, content and interpretation of accounting information

Septic shock in ICU: Advanced therapeutics, immunoparalysis and genomics. State of the art

Indexación: Web of Science; Scielo.En las últimas décadas, se han incorporado nuevos y trascendentes conceptos para el tratamiento avanzado del paciente en shock séptico. Se debe considerar el uso de terapia inmune en grupos seleccionados de pacientes. Las terapias de sustitución renal de carácter continuo sonbien toleradas y su empleo precoz evita sobrecargas de fluidos. El uso de hemofiltración de alto volumen puede jugar un papel en el paciente séptico hiperdinámico. La plasmaféresis es útil en el paciente con disfunción multiorgánica. El empleo de soporte extracorpóreo se debe considerar en quienes presentan shock séptico refractario. La inmunoparálisis se ha asociado con infecciones nosocomiales y mortalidad tardía. La información obtenida de los marcadores genéticos puede permitir la búsqueda de una medicina basada en la genómica.New and important concepts have emerged for the advanced management of the child with septic shock in the recent decades. Attending physicians in the Pediatric intensive care unit must be fully aware of them to improve patient care in the critical care unit. It should be considered the use of immune therapy only in selected groups of patients. Continuous renal replacement therapies are well tolerated and their early use prevents deleterious fluid overload. Removal of inflammatory mediators by using high volume hemofiltration may play a role in hyperdynamic septic patients. The use of plasmapheresis is recommended in patients with thrombocytopenia-associated multiple organ failure. Extracorporeal support use should be considered in those with refractory septic shock despite goals directed therapy. The immunoparalysis has been associated with nosocomial infections and late mortality. The information from genetic markers may allow early intervention and preventive genomics-based medicine.http://ref.scielo.org/g8m9m

Septic shock in pediatrics I. Current approach in diagnosis and therapeutics

Indexación: Web of Science; Scielo.El shock séptico es una de las principales causas de mortalidad infantil a nivel mundial y representa una compleja y progresiva vía inflamatoria secundaria a una enfermedad infecciosa, la cual origina disfunción cardiovascular aguda, no necesariamente hipotensión arterial, condicionando disoxia tisular y eventualmente falla celular y orgánica. Los paquetes de medidas de resucitación propuestos enfatizan el reconocimiento clínico y un tratamiento precoz. Estas intervenciones se basan en la pronta y agresiva resucitación con fluidos intravenosos para una adecuada perfusión tisular, administración de antibióticos, remoción del foco infeccioso y el uso de drogas vasoactivas en caso de ser necesario. La terapia debe evaluarse permanentemente según la normalización de metas clínicas y de laboratorio. En la presente publicación se actualiza el conocimiento de las características epidemiológicas y fisiopatológicas de la sepsis, una puesta al día en definiciones operacionales, campañas internacionales y referentes a las iniciativas propuestas para disminuir su morbimortalidad. Se aborda el enfoque terapéutico inicial en el servicio de urgencia. El objetivo de este artículo es dar a conocer el estado actual del conocimiento en el diagnóstico y tratamiento del paciente con shock séptico especialmente en su fase inicial previo al ingreso a UCI.Septic shock is a major cause of infant mortality worldwide and represents the progressive underlying inflammatory pathway secondary to an infectious disease, which causes acute cardiovascular dysfunction, not necessarily hypotension, tissue dysoxia and eventually cellular and organ failure. Standard resuscitative measures emphasize clinical recognition and early treatment. These interventions are based on early and aggressive resuscitation with intravenous fluids to optimize tissue perfusion, antibiotics, removal of the source of infection and the use of vasoactive drugs if necessary. Therapy should be permanently evaluated according to the standardized laboratory and clinical targets. This publication is an update on the epidemiology and pathophysiology of sepsis, operational definitions, current international campaigns and initiatives concerning proposals to decrease the morbidity and mortality of this condition. It also addresses initial therapeutic approaches in the emergency room. The aim of this study is to present the current state of knowledge in the diagnosis and treatment of patients with septic shock especially in the initial phase before admissions to intensive care units.http://ref.scielo.org/sbjrb

Septic shock in pediatrics II. Current concepts in diagnosis and treatment

Indexación: Web of Science; Scielo.Aunque los principios básicos para el diagnóstico y los pilares terapéuticos del niño con shock séptico se mantienen en el tiempo, es innegable que en las últimas décadas se han incorporado nuevos y trascendentes conceptos, siendo importante que el médico tratante en el Servicio de Urgencia tenga conocimiento a cabalidad de ellos. En la segunda parte de esta actualización se discuten las similitudes y diferencias entre la población infantil y adulta, la utilidad de las metas de reanimación metabólicas, como también el enfoque terapéutico inicial en el paciente séptico. Los conceptos más importantes revisados se refieren a las diferencias entre el niño y adulto con shock séptico, especialmente en la fisiopatología, clínica y tratamiento. Se recalca la importancia de expansión de la volemia y el uso de drogas vasoactivas si no hay respuesta a fluidos de reanimación. El manejo terapéutico debe estar orientado a la búsqueda de la normalización de metas macrohemodinámicas y de perfusión sistémica. Se deben evitar los errores más frecuentes de observar en el tratamiento inicial del paciente séptico. Esta entidad presenta una elevada incidencia y mortalidad, por lo cual el manejo precoz y agresivo es de máxima importancia en pediatría.Although the basic concepts of diagnosis and therapy of the child with septic shock have remained similar over time, it is undeniable that in recent decades, new and important concepts have been added, and any treating physician either at the Emergency Department or Intensive Care Unit should be fully aware of them. This second part discusses the similarities and differences between pediatric and adult populations, the utility of metabolic resuscitation goals, as well as the initial therapeutic approach in septic patients. The most important concepts of this work make reference to the differences between children and adults with septic shock, specifically regarding to pathophysiology, clinical presentation and treatment. Volume expansion and vasoactive drugs are crucial if there is no response to fluid resuscitation. The therapeutic management should focus on finding the normalization of macrohemodynamic and systemic perfusion targets. Common observation mistakes in the initial treatment of septic patients should be avoided. This condition has a high incidence and mortality rate; therefore an early and aggressive treatment is essential.http://ref.scielo.org/cc6t3

New insights in the global cycle of acetonitrile: release from the ocean and acetonitrile: release from the ocean and Venezuela

International audienceCUsing the proton transfer reaction mass spectrometry (PTR-MS) technique, acetonitrile was measured during the wet season in a Venezuelan woodland savanna. The site was located downwind of the Caribbean Sea and no biomass burning events were observed in the region. High boundary layer concentrations of 211 ±36 pmol/mol (median, ± standard deviation) were observed during daytime in the well mixed boundary layer, which is about 60 pmol/mol above background concentrations recently measured over the Mediterranean Sea and the Pacific Ocean. Most likely acetonitrile is released from the warm waters of the Caribbean Sea thereby enhancing mixing ratios over Venezuela. Acetonitrile concentrations will probably still be much higher in biomass burning plumes, however, the general suitability of acetonitrile as a biomass burning marker should be treated with care. During nights, acetonitrile dropped to levels typically around 120 pmol/mol, which is consistent with a dry deposition velocity of ~0.14 cm/s when a nocturnal boundary layer height of 100 m is assumed

A quantitative analysis of objective feather color assessment: Measurements in the laboratory do not reflect true plumage color

© 2016 American Ornithologists' Union.An important driver of the evolution of animal coloration is sexual selection operating on traits that are used to transmit information to rivals and potential mates, which has a major impact on fitness. Reflectance spectrometry has become a standard color-measuring tool, especially after the discovery of tetrachromacy in birds and their ability to detect UV light. Birds' plumage patterns may be invisible to humans, and therefore the establishment of reliable and quantitatively objective ways of assessing coloration not dependent on human vision is a technical need of primary importance. Plumage coloration measurements can be taken directly on live birds in the field, or in the laboratory (e.g., on collected feathers). However, which of these 2 approaches offers a more reliable, repeatable sampling method remains an unsolved question. Using a spectrophotometer, we measured melanin-based coloration in the plumage of Barn Swallows (Hirundo rustica). We assessed the repeatability of measures obtained with both traditional sampling methods to quantitatively determine their reliability. We used an ANOVA-based method for calculating the repeatability of measurements from 2 years separately, and a GLMM-based method to calculate overall adjusted repeatabilities for both years. The results of our study indicate a great disparity between color measurements obtained using both sampling methods and a low comparability across them. Assuming that measurements taken in the field reflect the real or "true" color of plumage, we may conclude that there is a lack of reliability of the laboratory method to reflect this true color in melanin-based plumages. Likewise, we recommend the use of the GLMM-based statistical method for repeatability calculations, as it allows the inclusion of random factors and the calculation of more realistic, adjusted repeatabilities. It also reduces the number of necessary tests, thereby increasing power, and it allows easy calculation of 95% CIs, a measure of the reliability and precision of effect-size calculations.published_or_final_versio