294 research outputs found
Families index for Boutet de Monvel operators
We define the analytical and the topological indices for continuous families of operators in the C*-closure of the Boutet de Monvel algebra. Using techniques of C*-algebra, K-theory, and the Atiyah–Singer theorem for families of elliptic operators on a closed manifold, we prove that these two indices coincide
ESTIMATIVA DO ISEW PARA MUNICÍPIOS DO POLO PETROLINA-JUAZEIRO: RESULTADOS PRELIMINARES
O pólo Petrolina-Juazeiro possui uma economia fortemente baseada na agricultura irrigada; identificada como única alternativa de transformação econômica e social da região, uma vez que esta enfrenta uma assombrosa realidade de seca. Estas constatações sobre irrigação relativas à sua instituição na micro região do semi-árido nordestino são relativamente recentes; sendo a própria experiência do pólo um baluarte delas. Mas a sustentabilidade da atividade na região tem sido questionada, principalmente devido à sua forte dependência ambiental, em particular do recurso hídrico. Ao se basear na irrigação para produção agrícola, e ser esta a propulsora dos efeitos multiplicadores da renda regional, pode-se dizer que o desenvolvimento do pólo é altamente dependente das condições produtivas da terra e da disponibilidade e qualidade da água do rio São Francisco. Este artigo tem como objetivo testar a hipótese da insustentabilidade, utilizando-se, para isto, do cálculo do ISEW para municípios selecionados do pólo. É proposta uma metodologia de cálculo dos diversos itens do ISEW em nível municipal, fazendo-se as adaptações necessárias devido ao nível de agregação dos dados e de disponibilidade dos dados. Os resultados são ainda parciais, mas tem se mostrado coerentes com os resultados obtidos para outros estudos.Pólo Petrolina/Juazeiro, sustentabilidade, ISEW, Livestock Production/Industries,
New record of Clypeasterophilus stebbingi (Rathbun, 1918) (Decapoda: Brachyura: Pinnotheridae) from the east coast of Nicaragua
An overview of Listeria monocytogenes contamination in ready to eat meat, dairy and fishery foods
Dissodactylus crinitichelis Moreira, 1901 and Leodia sexiesperforata (Leske, 1778): first record of this symbiosis in Brazil
Mapping child growth failure across low- and middle-income countries
Childhood malnutrition is associated with high morbidity and mortality globally1. Undernourished children are more likely to experience cognitive, physical, and metabolic developmental impairments that can lead to later cardiovascular disease, reduced intellectual ability and school attainment, and reduced economic productivity in adulthood2. Child growth failure (CGF), expressed as stunting, wasting, and underweight in children under five years of age (0�59 months), is a specific subset of undernutrition characterized by insufficient height or weight against age-specific growth reference standards3�5. The prevalence of stunting, wasting, or underweight in children under five is the proportion of children with a height-for-age, weight-for-height, or weight-for-age z-score, respectively, that is more than two standard deviations below the World Health Organization�s median growth reference standards for a healthy population6. Subnational estimates of CGF report substantial heterogeneity within countries, but are available primarily at the first administrative level (for example, states or provinces)7; the uneven geographical distribution of CGF has motivated further calls for assessments that can match the local scale of many public health programmes8. Building from our previous work mapping CGF in Africa9, here we provide the first, to our knowledge, mapped high-spatial-resolution estimates of CGF indicators from 2000 to 2017 across 105 low- and middle-income countries (LMICs), where 99 of affected children live1, aggregated to policy-relevant first and second (for example, districts or counties) administrative-level units and national levels. Despite remarkable declines over the study period, many LMICs remain far from the ambitious World Health Organization Global Nutrition Targets to reduce stunting by 40 and wasting to less than 5 by 2025. Large disparities in prevalence and progress exist across and within countries; our maps identify high-prevalence areas even within nations otherwise succeeding in reducing overall CGF prevalence. By highlighting where the highest-need populations reside, these geospatial estimates can support policy-makers in planning interventions that are adapted locally and in efficiently directing resources towards reducing CGF and its health implications. © 2020, The Author(s)
Techniques for measuring aerosol attenuation using the Central Laser Facility at the Pierre Auger Observatory
The Pierre Auger Observatory in Malargüe, Argentina, is designed to study the properties of ultra-high energy cosmic rays with energies above 10(18) eV. It is a hybrid facility that employs a Fluorescence Detector to perform nearly calorimetric measurements of Extensive Air Shower energies. To obtain reliable calorimetric information from the FD, the atmospheric conditions at the observatory need to be continuously monitored during data acquisition. In particular, light attenuation due to aerosols is an important atmospheric correction. The aerosol concentration is highly variable, so that the aerosol attenuation needs to be evaluated hourly. We use light from the Central Laser Facility, located near the center of the observatory site, having an optical signature comparable to that of the highest energy showers detected by the FD. This paper presents two procedures developed to retrieve the aerosol attenuation of fluorescence light from CLF laser shots. Cross checks between the two methods demonstrate that results from both analyses are compatible, and that the uncertainties are well understood. The measurements of the aerosol attenuation provided by the two procedures are currently used at the Pierre Auger Observatory to reconstruct air shower data
The rapid atmospheric monitoring system of the Pierre Auger Observatory
The Pierre Auger Observatory is a facility built to detect air showers produced by cosmic rays above 10(17) eV. During clear nights with a low illuminated moon fraction, the UV fluorescence light produced by air showers is recorded by optical telescopes at the Observatory. To correct the observations for variations in atmospheric conditions, atmospheric monitoring is performed at regular intervals ranging from several minutes (for cloud identification) to several hours (for aerosol conditions) to several days (for vertical profiles of temperature, pressure, and humidity). In 2009, the monitoring program was upgraded to allow for additional targeted measurements of atmospheric conditions shortly after the detection of air showers of special interest, e. g., showers produced by very high-energy cosmic rays or showers with atypical longitudinal profiles. The former events are of particular importance for the determination of the energy scale of the Observatory, and the latter are characteristic of unusual air shower physics or exotic primary particle types. The purpose of targeted (or 'rapid') monitoring is to improve the resolution of the atmospheric measurements for such events. In this paper, we report on the implementation of the rapid monitoring program and its current status. The rapid monitoring data have been analyzed and applied to the reconstruction of air showers of high interest, and indicate that the air fluorescence measurements affected by clouds and aerosols are effectively corrected using measurements from the regular atmospheric monitoring program. We find that the rapid monitoring program has potential for supporting dedicated physics analyses beyond the standard event reconstruction
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