Soil and water pollution in a banana production region in tropical Mexico

The effects of abundant Mancozeb (Mn, Zn— bisdithiocarbamate) applications (2.5 kg ha-1week-1 for 10 years) on soil and surface-, subsurface- and groundwater pollution were monitored in a banana production region of tropical Mexico. In soils, severe manganese accumulation was observed, wheras the main metabolite ethylenethiourea was near the detection limit. Surface and subsurface water was highly polluted with ethylenethiourea, the main metabolite of Mancozeb (22.5 and 4.3 lg L-1, respectively), but not with manganese. In deep ground water, no ethylenethiourea was detected. The level of pollution in the region presents a worrisome risk for aquatic life and for human health

Estimación de la ganancia genética en soya (Glycine max (L.) merril) en doce (12) años de mejoramiento varietal del C.I. Palmira, Colombia

La eficiencia del Programa de Mejoramiento Genético de Soya del C.l. Palmira fue evaluada, utilizando los datos obtenidos en los ensayos de rendimiento de líneas y/o variedades. El propósito principal de esta investigación fue determinar el progreso genético alcanzado en un período de 12 años (de 1980 a 1991), en los semestres A y B. Los ensayos de rendimiento fueron sembrados en el C.l. Palmira, Colombia, localizado a 1080 m.s.n.m., 3°3V de latitud norte y 76819' de longitud oeste; temperatura promedia de 24°C y una precipitación de 1000 mm.Soya-Soja- Glycine maxSoy

Spectral signatures of many-body localization with interacting photons

Statistical mechanics is founded on the assumption that a system can reach thermal equilibrium, regardless of the starting state. Interactions between particles facilitate thermalization, but, can interacting systems always equilibrate regardless of parameter values\,? The energy spectrum of a system can answer this question and reveal the nature of the underlying phases. However, most experimental techniques only indirectly probe the many-body energy spectrum. Using a chain of nine superconducting qubits, we implement a novel technique for directly resolving the energy levels of interacting photons. We benchmark this method by capturing the intricate energy spectrum predicted for 2D electrons in a magnetic field, the Hofstadter butterfly. By increasing disorder, the spatial extent of energy eigenstates at the edge of the energy band shrink, suggesting the formation of a mobility edge. At strong disorder, the energy levels cease to repel one another and their statistics approaches a Poisson distribution - the hallmark of transition from the thermalized to the many-body localized phase. Our work introduces a new many-body spectroscopy technique to study quantum phases of matter

Evaluating the yield of surviving plants from early-season hail damage in corn: A field survey

Economic losses due to hailstorms acrossUS corn fields occur every year.Hailstorms result in leaf defoliation, decreasing photosynthetic area and impairing carbon assimilation and crop yield for all corn (Zea mays L.) development stages. However, more attention is often given to stand reductions rather than damage to stems or leaf defoliation. During the 2014 growing season, a natural hail event affected many areas of eastern Nebraska. Twelve affected corn fields were surveyed and included in this study. An injury score scale (1–5) was developed based on various injury and severity levels before the V6 (6-leaf corn growth stage) (six-collared leaves). Scores were assigned to affected fields approximately 10–15 days after the hailstorm. At the end of the growing season, ears were harvested, and grain yield per plant was determined. The highest grain yield (p \u3c 0.05) was recorded with plants that were affected but retained a main stem in good condition, albeit defoliation was present (score 1, lowest damage category). In contrast, when the main stem was cut and the plant had poor regrowth (score 3), yields were reduced by approximately 53% compared to plants with an injury score of 1. A significant negative linear relationship (R2 = 0.63, p \u3c 0.01) between injury score and yield was observed (higher injury score from hail events resulted in lower yields). Based on these results, corn yield reduction due to plant injury from hail events before V6 should not be only attributed to stand reductions. Our findings indicate an opportunity to adjust the US evaluation standards for early-season hail damage events in corn fields

Consumo de oxígeno (V02) indirecto en militares con diagnóstico de enfermedad aguda de montaña

Objetivo: Comparar los promedios de consumo de oxígeno medido de manera indirecta entre militares con diagnóstico de enfermedad aguda de montaña (EAM) y militares sin diagnóstico utilizando criterios de la escala Lake Louise.Material y métodos: Estudio de casos y controles, con un período de recolección de datos comprendido entre el año 2008 y 2009 en una localidad ubicada a 3050 msnm, en Bogotá DC, Colombia. El estudio involucró la realización de una prueba de lanzadera de 20 metros para la medición del consumo de oxígeno indirecto (V02) y VO, ajustado por kilogramo (V02/kg) máximo, y la aplicación del cuestionario de Lake Louise para diagnóstico de Enfermedad Aguda de Montaña (EAM). Se obtuvieron 62 sujetos con EAM y 61 sin EAM, se realizó una descripción de las características demográficas y variables vitales realizando posteriormente un análisis bivariado de los datos obtenidos con las variables V02 y V02/kg máximos.Resultados: De 123 sujetos, 62 fueron diagnosticados con EAM (casos) y 61 no presentaron la enfermedad (controles). La mayoría de los enfermos presentó una EAM de tipo leve (35%), la mediana de tiempo de exposición fue 10 días (RIQ: 10). Del total de los sujetos, 30.1% tenían antecedente de tabaquismo. El antecedente de ascenso previo a una altitud mayor de 3050 msnm estuvo asociado de manera independiente a una menor probabilidad de desarrollar la enfermedad OR: 0,41 (1C95%: 0,19 - 0,87). Adicionalmente la ausencia de consumo de tabaco mostró un mayor riesgo de presentar la EAM. OR: 2,33 (IC95%; 1,05 - 5,17) No existieron diferencias significativas del V02y V02/Kg máximos entre los sujetos con EAM y sujetos sin la enfermedad, con p=0,46 y p=0,34 respectivamente.Conclusión: La medición de VO, máximo indirecto no muestra diferencias en sujetos con y sin EAM a 3050 msnm, el ascenso previo en altitud y el antecedente de consumo de cigarrillo se comportaron como factores protectores para el desarrollo de EAM. Se requieren estudios posteriores para corroborar los hallazgos de estos dos puntos específicos

Hidden Order in Quantum Many-body Dynamics of Driven-Dissipative Nonlinear Photonic Lattices

We study the dynamics of nonlinear photonic lattices driven by two-photon parametric processes. By means of matrix-product-state based calculations, we show that a quantum many-body state with long-range hidden order can be generated from the vacuum. This order resembles that characterizing the Haldane insulator. A possible explanation highlighting the role of the symmetry of the drive, and the effect of photon loss are discussed. An implementation based in superconducting circuits is proposed and analyzedComment: 10 pages, 5 figure

Understanding Dwarf Galaxies in order to Understand Dark Matter

Much progress has been made in recent years by the galaxy simulation community in making realistic galaxies, mostly by more accurately capturing the effects of baryons on the structural evolution of dark matter halos at high resolutions. This progress has altered theoretical expectations for galaxy evolution within a Cold Dark Matter (CDM) model, reconciling many earlier discrepancies between theory and observations. Despite this reconciliation, CDM may not be an accurate model for our Universe. Much more work must be done to understand the predictions for galaxy formation within alternative dark matter models.Comment: Refereed contribution to the Proceedings of the Simons Symposium on Illuminating Dark Matter, to be published by Springe

Features of patients hospitalized to the newborn intensive care at Clínica Universidad de La Sabana

Introducción: Es pertinente conocer las características de los pacientes que ingresan a las unidades de cuidado intensivo neonatal para que las acciones en salud respondan a sus necesidades particulares. Objetivo: Caracterizar los pacientes que ingresaron a la Unidad de Cuidado Intensivo Neonatal (UCIN) de la Clínica de la Universidad de La Sabana de enero a diciembre del 2012. Materiales y Métodos: estudio retrospectivo con n=206 neonatos que ingresaron a la UCIN de la Clínica Universidad de La Sabana en el 2012, se revisaron las historias clínicas de los pacientes ingresados para identificar sus características, se calcularon frecuencias relativas y absolutas; y para las variables cuantitativas se describieron medidas de tendencia central y dispersión. Resultados: el 56,3% eran hombres, el promedio de edad gestacional de 36,5 semanas (SD 3,3 semanas), el peso promedio fue de 2625,9 g (SD 757,5 g). La mediana de los días de estancia fue de 4 (IQR: 2 a 9). El principal diagnóstico fue ictericia neonatal en (21,8%), el 22% de los pacientes requirieron ventilación mecánica (VM). La media de la edad gestacional y del peso en pacientes con requerimientos de VM fue de 32.7 semanas (SD: 3,7 semanas) y 1883 g (SD: 779 g) respectivamente, comparado con 37,6 semanas (SD: 2,2 semanas) y 2840 g (SD: 601 g) en los que no requirieron VM. Conclusiones: características como bajo peso al nacer, edad gestacional temprana y el uso de surfactante, seasociaron con el requerimiento de VM, adicionalmente la mortalidad calculada fue del 2,8%.Introduction: It is relevant to know the characteristics of patients who enter to neonatal intensive care units in order to learn how to respond to their specific conditions and which health actions can be applied for their particular needs. Objective: The aim of this study is describe patients admitted at Clinica Universidad de La Sabana (Neonatal Intensive Care -NIC) from January to December 2012. Materials and Methods: Retrospective study with n=206 neonates admitted to the NIC at Clinica Universidad de La Sabana in 2012, medical records of patients admitted were reviewed to identify its characteristics, as well absolute and relative frequencies were calculated. In terms of quantitative variables, they were measured with central tendency and dispersion. Results: 56.3% of patients were men, the average gestational age was 36.5 weeks (SD 3.3 weeks), the average weight was 2625 gr (SD 757.5 gr). The median days of stay was 4 (IQR:2-9). The main diagnosis was neonatal icterus (21.8%); 22% of patient’s required mechanical ventilation (MV). The mean gestational age and weight in patients with VM requirements was 32.7 weeks (SD: 3.7 weeks) and 1883 gr (SD: 779 gr) respectively. Contrasted with the gestational age and weight of newborns that not requiring VM was 37.6 weeks (SD 2.2 weeks) and 2840 gr (SD: 601 gr). Conclusions: Low birth weight, early gestational age and the use of surfactant, were associated with the requirement of VM, and the mortality found was 2.8% for the whole cohort

Evidence for an Allelopathic Interaction Between Rye and Wild Oats

Allelopathy is a biological phenomenon in which an organism produces one or more biochemicals that influence the growth, survival, and reproduction of other organisms. Allelopathy has been the subject of a great deal of research in chemical ecology since the 1930s. The characterization of the factors that influence this phenomenon has barely been explored, mainly due to the complexity of this area. The main aim of the research carried out to date has been to shed light on the importance of these interactions in agroecosystems, especially in relation to the interactions between crops and weeds. Herein we report the characterization of a complete allelochemical pathway involving benzoxazinones, which are known to participate in allelopathic plant defense interactions of several plants of high agronomic interest. The production of the defense chemicals by a donor plant (crop), the route and transformations of the chemicals released into the environment, and the uptake and phytotoxic effects on a target plant (weed) were all monitored. The results of this study, which is the first of its kind, allowed a complete dynamic characterization of the allelopathic phenomenon for benzoxazinones

Caribbean Corals in Crisis: Record Thermal Stress, Bleaching, and Mortality in 2005

BACKGROUND The rising temperature of the world's oceans has become a major threat to coral reefs globally as the severity and frequency of mass coral bleaching and mortality events increase. In 2005, high ocean temperatures in the tropical Atlantic and Caribbean resulted in the most severe bleaching event ever recorded in the basin. METHODOLOGY/PRINCIPAL FINDINGS Satellite-based tools provided warnings for coral reef managers and scientists, guiding both the timing and location of researchers' field observations as anomalously warm conditions developed and spread across the greater Caribbean region from June to October 2005. Field surveys of bleaching and mortality exceeded prior efforts in detail and extent, and provided a new standard for documenting the effects of bleaching and for testing nowcast and forecast products. Collaborators from 22 countries undertook the most comprehensive documentation of basin-scale bleaching to date and found that over 80% of corals bleached and over 40% died at many sites. The most severe bleaching coincided with waters nearest a western Atlantic warm pool that was centered off the northern end of the Lesser Antilles. CONCLUSIONS/SIGNIFICANCE Thermal stress during the 2005 event exceeded any observed from the Caribbean in the prior 20 years, and regionally-averaged temperatures were the warmest in over 150 years. Comparison of satellite data against field surveys demonstrated a significant predictive relationship between accumulated heat stress (measured using NOAA Coral Reef Watch's Degree Heating Weeks) and bleaching intensity. This severe, widespread bleaching and mortality will undoubtedly have long-term consequences for reef ecosystems and suggests a troubled future for tropical marine ecosystems under a warming climate.This work was partially supported by salaries from the NOAA Coral Reef Conservation Program to the NOAA Coral Reef Conservation Program authors. NOAA provided funding to Caribbean ReefCheck investigators to undertake surveys of bleaching and mortality. Otherwise, no funding from outside authors' institutions was necessary for the undertaking of this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript