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Effect of 7 yr of experimental drought on vegetation dynamics and biomass storage of an eastern Amazonian rainforest

P>At least one climate model predicts severe reductions of rainfall over Amazonia during this century. Long-term throughfall exclusion (TFE) experiments represent the best available means to investigate the resilience of the Amazon rainforest to such droughts. Results are presented from a 7 yr TFE study at Caxiuana National Forest, eastern Amazonia. We focus on the impacts of the drought on tree m

Radial Nanowire Light-Emitting Diodes in the (AlxGa1-x)yIn1-yP Material System.

Nanowires have the potential to play an important role for next-generation light-emitting diodes. In this work, we present a growth scheme for radial nanowire quantum-well structures in the AlGaInP material system using a GaInP nanowire core as a template for radial growth with GaInP as the active layer for emission and AlGaInP as charge carrier barriers. The different layers were analyzed by X-ra

Photoluminescence study of Zn-doped wurtzite InP core-shell nanowires

In situ Zn doping of InP shells on nanowires in the wurtzite crystal structure has been investigated using diethyl zinc (DEZn) as a precursor. Photoluminescence measurements of single nanowires unexpectedly exhibit an acceptor-related peak at room temperature, in contrast to thin films grown at identical conditions. This peak is observable even using low DEZn molar fractions, which indicates effic

Inclusive deep inelastic scattering at high Q(2) with longitudinally polarised lepton beams at HERA

Inclusive e(+/-)p single and double differential cross sections for neutral and charged current deep inelastic scattering processes are measured with the H1 detector at HERA. The data were taken at a centre-of-mass energy of root s = 319 GeV with a total integrated luminosity of 333.7 pb(-1) shared between two lepton beam charges and two longitudinal lepton polarisation modes. The differential cro

Human Adaptation to Arsenic-Rich Environments.

Adaptation drives genomic changes; however, evidence of specific adaptations in humans remains limited. We found that inhabitants of the northern Argentinean Andes, an arid region where elevated arsenic concentrations in available drinking water is common, have unique arsenic metabolism, with efficient methylation and excretion of the major metabolite dimethylated arsenic and a less excretion of t

Organ-sparing reconstructive surgery in penile cancer: initial experiences at two Swedish referral centres.

Abstract Objective. The aim of this study was to present early outcome data for patients treated for penile cancer with organ-sparing reconstructive surgery at two referral centres in Sweden. Material and methods. Oncological, cosmetic and functional outcome and complications were analysed retrospectively during the period 2011-2013. Twelve patients with non-invasive penile cancer were treated wit

Genetic variation in mitotic regulatory pathway genes is associated with breast tumor grade.

Mitotic index is an important component of histologic grade and has an etiologic role in breast tumorigenesis. Several small candidate gene studies have reported associations between variation in mitotic genes and breast cancer risk. We measured associations between 2,156 single nucleotide polymorphisms (SNPs) from 194 mitotic genes and breast cancer risk, overall and by histologic grade, in the B

Cross-species utility of 22 microsatellite markers in the Melodious Warbler (Hippolais polyglotta)

Microsatellites are a valuable tool in the analysis of population genetic structure. Utilising microsatellite markers that were originally isolated from other species (cross-species amplification) can prove an efficient way, in terms of time and cost, to obtain markers for genetic studies. Here, 55 avian microsatellite primer pairs were tested for the cross-amplification in the Melodious Warbler (

Exposure to websites that encourage self-harm and suicide: Prevalence rates and association with actual thoughts of self-harm and thoughts of suicide in the United States.

This article provides 12-month prevalence rates of youth exposure to websites which encourage self-harm or suicide and examines whether such exposure is related to thoughts of self-harm and thoughts of suicide in the past 30 days. Data were collected via telephone from a nationally representative survey of 1560 Internet-using youth, ages 10-17 residing in the United States. One percent (95% CI: 0.

Flame structure analysis for categorization of lean premixed CH4/air and H-2/air flames at high Karlovitz numbers: Direct numerical simulation studies

This paper presents direct numerical simulation studies of lean CH4/air and H-2/air flames at high Karlovitz numbers utilizing detailed chemical kinetic mechanisms. Identical Karlovitz numbers are applied to the two flames; however, as the interaction of high turbulence intensity small scale structures with the reaction zones is considered, a significant difference in the effect of the turbulence

On the Microlocal Properties of the Range of Systems of Principal Type

The purpose of this paper is to study microlocal conditions for inclusion relations between the ranges of square systems of pseudodifferential operators which fail to be locally solvable. The work is an extension of earlier results for the scalar case in this direction, where analogues of results by L. Hormander about inclusion relations between the ranges of first order differential operators wit

Herpes Simplex Encephalitis: Lack of Clinical Benefit of Long-Term Valacyclovir Therapy.

Despite the proven efficacy of acyclovir therapy, herpes simplex encephalitis (HSE) continues to cause substantial morbidity and mortality. Among patients with HSE treated with acyclovir (ACV), the mortality rate is approximately 14-19%. Among survivors, 45-60% have neuropsychological sequelae at 1 year. Thus, improving therapeutic approaches to HSE remains a high priority.

Extracting Data from WSNs: A Service-Oriented Approach

This chapter describes the architecture of a middleware layer between low-level sensing devices and higher level software layers, to support the requirements of a software infrastructure for networked enterprises. The development of such middleware layer is an important problem, as demonstrated by the number or research papers and the variety of approaches that can be found in literature. The main

Carrier Recombination Dynamics in Sulfur-Doped InP Nanowires.

Measuring lifetime of photogenerated charges in semiconductor nanowires (NW) is important for understanding light-induced processes in these materials and is relevant for their photovoltaic and photodetector applications. In this paper, we investigate the dynamics of photogenerated charge carriers in a series of as-grown InP NW with different levels of sulfur (S) doping. We observe that photolumin

Optimal results for the nonhomogeneous initial-boundary value problem for the two-dimensional Navier-Stokes equations

In this work we study the fully nonhomogeneous initial boundary value problem for the two-dimensional time-dependent Navier–Stokes equations in a general open space domain in R2 with low regularity assumptions on the initial and the boundary value data. We show that the perturbed Navier–Stokes operator is a diffeomorphism from a suitable function space onto its own dual and as a corollary we get t

Brain Areas Consistently Linked to Individual Differences in Perceptual Decision-making in Younger as well as Older Adults before and after Training

Perceptual decision-making performance depends on several cognitive and neural processes. Here, we fit Ratcliff's diffusion model to accuracy data and reaction-time distributions from one numerical and one verbal two-choice perceptual-decision task to deconstruct these performance measures into the rate of evidence accumulation (i.e., drift rate), response criterion setting (i.e., boundary separat