Effects of branching spatial structure and life history on the asymptotic growth rate of a population

Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Theoretical Ecology 3 (2010): 137-152, doi:10.1007/s12080-009-0058-0.The dendritic structure of a river network creates directional dispersal and a hierarchical arrangement of habitats. These two features have important consequences for the ecological dynamics of species living within the network.We apply matrix population models to a stage-structured population in a network of habitat patches connected in a dendritic arrangement. By considering a range of life histories and dispersal patterns, both constant in time and seasonal, we illustrate how spatial structure, directional dispersal, survival, and reproduction interact to determine population growth rate and distribution. We investigate the sensitivity of the asymptotic growth rate to the demographic parameters of the model, the system size, and the connections between the patches. Although some general patterns emerge, we find that a species’ mode of reproduction and dispersal are quite important in its response to changes in its life history parameters or in the spatial structure. The framework we use here can be customized to incorporate a wide range of demographic and dispersal scenarios.Funding for this work came from the James S. McDonnell Foundation (EEG, HJL, WFF). MGN was supported by grants from the National Science Foundation (CMG-0530830, OCE-0326734, ATM-0428122)

First Measurement of the Total Neutron Cross Section on Argon Between 100 and 800 MeV

We report the first measurement of the neutron cross section on argon in the energy range of 100-800 MeV. The measurement was obtained with a 4.3-hour exposure of the Mini-CAPTAIN detector to the WNR/LANSCE beam at LANL. The total cross section is measured from the attenuation coefficient of the neutron flux as it traverses the liquid argon volume. A set of 2,631 candidate interactions is divided in bins of the neutron kinetic energy calculated from time-of-flight measurements. These interactions are reconstructed with custom-made algorithms specifically designed for the data in a time projection chamber the size of the Mini-CAPTAIN detector. The energy averaged cross section is $0.91 \pm{} 0.10~\mathrm{(stat.)} \pm{} 0.09~\mathrm{(sys.)}~\mathrm{barns}$. A comparison of the measured cross section is made to the GEANT4 and FLUKA event generator packages.Comment: 5 pages, 1 table, 3 figures, submitted to Physical Review Letter

World Society of Emergency Surgery (WSES) guidelines for management of skin and soft tissue infections

Peer reviewe

Desempenho nas habilidades auditivas de atenção seletiva e memória auditiva em um grupo de idosos protetizados: influência de perda auditiva, idade e gênero Performance in the auditory abilities of selective attention and hearing memory in a group of elderly with hearing aids: Influence of hearing loss, age and gender

OBJETIVOS: verificar o desempenho nas habilidades auditivas de atenção seletiva e memória auditiva de idosos protetizados e relacioná-lo com o grau e configuração de perda auditiva, o gênero e a idade. MÉTODO: foram avaliados 29 idosos de 60 a 84 anos, sendo 17 (58,62%) do gênero feminino e 12 (41,38%) do gênero masculino. As avaliações realizadas incluíram meatoscopia, audiometria tonal liminar e aplicação do teste SSW em português. RESULTADOS: a análise dos dados permitiu verificar que, neste grupo de indivíduos, a idade e o grau de perda auditiva influenciaram significantemente nos escores obtidos na avaliação do processamento auditivo, diferentemente das demais variáveis. Os idosos que apresentaram perda auditiva de grau leve com configuração horizontal obtiveram escores significantemente superiores na avaliação do processamento auditivo comparados com os portadores de perda auditiva de grau moderado com configuração horizontal ou grau moderado com configuração descendente. Idosos pertencentes a faixa etária de 60-69 obtiveram desempenho superiormente significante comparado com idosos na faixa etária de 80-89 CONCLUSÃO: concluiu-se que o grau de perda auditiva e a idade influenciam nos resultados da avaliação do processamento auditivo. O gênero e a configuração de perda auditiva não foram fatores determinantes na avaliação do processamento auditivo.<br>PURPOSE: to verify the performance in the auditory abilities of selective attention and hearing memory of elderly with prosthesis and relate it to the degree and the configuration of hearing loss, the gender and the age. METHOD: 29 elderly people from 60 to 84 years old were evaluated, 17 of them (58,62%) females and 12 (41,38%) males. The evaluations carried out included meatoscopy, audiometry evaluation and the use of the SSW test in Portuguese. RESULTS: the analysis of the data showed that, in this group of individuals, the age and the degree of auditory loss influenced significantly in the scores obtained in the evaluation of the auditory process, unlike the other variables. The elderly that showed light degree with horizontal configuration obtained scores significantly higher than the ones who had auditory loss in moderate degree with horizontal configuration or moderate degree with descending configuration. Elderly belonging to the age range 60 to 69 years old obtained performance significantly superior when compared with the ones in the age range of 80 to 89 years old. CONCLUSION: it was concluded that the degree of hearing loss and the age influenced the evaluation of the auditory processing. The gender and the configuration of hearing loss were not significant determining factors in the evaluation of the auditory processing

Fasciíte necrosante: revisão com enfoque nos aspectos dermatológicos Necrotizing fasciitis: new insights with a focus on dermatological aspects

Fasciíte necrosante é infecção bacteriana destrutiva e rapidamente progressiva do tecido subcutâneo e fáscia superficial, associada a altos índices de morbimortalidade, se não tiver tratamento precoce. Recentemente, inúmeros casos publicados têm demonstrado aumento na freqüência e gravidade dessa infecção, particularmente causada pelo Streptococcus do grupo A (GAS) e que acomete até mesmo pessoas jovens e saudáveis. Classifica-se em tipo I, quando causada por flora mista de anaeróbios e outras bactérias, e tipo II, quando causada pelo GAS isolado ou associado ao Staphylococcus aureus. Os fatores predisponentes incluem: doenças crônicas e malignas, abuso de álcool, uso de drogas endovenosas, lesões da pele como varicela, úlceras crônicas, psoríase, cirurgia, traumas abertos e fechados, entre outros. Clinicamente destacam-se: a dor intensa, o edema grave, a rápida progressão e a resposta pobre à antibioticoterapia. É necessário um alto índice de suspeição para o diagnóstico clínico, que é confirmado à intervenção cirúrgica, com a evidência de necrose da fáscia superficial. Os exames radiológicos são úteis, e o diagnóstico diferencial deve ser feito principalmente com celulite em seu estágio inicial. O tratamento, que deve ser precoce, é feito com antibióticos de amplo espectro, debridamento cirúrgico agressivo e medidas de suporte clínico e nutricional.<br>Necrotizing fasciitis is a destructive and quickly progressing bacterial infection of the subcutaneous layer and superficial fascia. It is associated with high levels of unhealthiness and mortality if not treated early. Recently, countless published cases demonstrated an increasing frequency and severity of these infections, especially those caused by Group A Streptococcus (GAS), which afflicts even young and healthy persons. It is classified as type I when caused by a mixed anaerobic flora and other bacteria, and type II when caused by GAS alone or in association with Staphylococcus aureus. Predisposing factors include: chronic and malignant diseases, alcohol abuse, intravenous drug use, skin lesions such as chicken pox, chronic ulcers, psoriasis, surgery, and opened or closed traumas, among others. Clinical features are intense pain, severe edema, fast progress and poor antibiotic therapy feedback. A high level of suspicion is necessary to achieve a clinical diagnosis for this disease. Moreover, it is confirmed primarily when surgery takes place and reveals the superficial fascia necrosis. Radiological examinations are useful and the differential diagnosis must be done mainly with cellulitis at its initial stage. Treatment must be done early and with broad spectrum antibiotics, aggressive surgical debridement and clinical and nutritional support measures

Necrotizing fasciitis: a surgical emergency

none5Accurate assessment and timely interventions are critical in the treatment of patients affected with necrotizing fasciitis, a rare, fulminating, potentially life-threatening, infectious process of the soft tissues. Understanding the natural history and unique characteristics of this disease is crucial to achieve early recognition, effective management and a favorable patient outcome. Classic symptoms include severe pain, erythema, mottling, crepitus, skin anesthesia, warmth, tenderness, bullous formations and edema in the affected area and fever. This article aims at reviewing the information known about this disease, collected from various sources. Radical surgical debridement, broad-spectrum antibiotics, negative pressure wound therapy and hyperbaric oxygen therapy are considered to be the cornerstones of treatment.mixedD. de Tullio; C. Rossi; S. Bolzon; L. Scagliarini; S. OcchionorelliDE TULLIO, Damiano; Rossi, Camilla; Bolzon, Stefano; Scagliarini, Lucia; Occhionorelli, Savin