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Cloud condensation nuclei in pristine tropical rainforest air of Amazonia: size-resolved measurements and modeling of atmospheric aerosol composition and CCN activity

Atmospheric aerosol particles serving as cloud condensation nuclei (CCN) are key elements of the hydrological cycle and climate. We have measured and characterized CCN at water vapor supersaturations in the range of S=0.10-0.82% in pristine tropical rainforest air during the AMAZE-08 campaign in central Amazonia. The effective hygroscopicity parameters describing the influence of chemical composit

High temporal resolution tracing of photosynthate carbon from the tree canopy to forest soil microorganisms

Half of the biological activity in forest soils is supported by recent tree photosynthate, but no study has traced in detail this flux of carbon from the canopy to soil microorganisms in the field. Using (CO2)-C-13, we pulse-labelled over 1.5 h a 50-m(2) patch of 4-m-tall boreal Pinus sylvestris forest in a 200-m(3) chamber. Tracer levels peaked after 24 h in soluble carbohydrates in the phloem at

Protein D of Haemophilus influenzae: a protective nontypeable H. influenzae antigen and a carrier for pneumococcal conjugate vaccines.

Protein D (PD) is a highly conserved 42 kDa surface lipoprotein found in all Haemophilus influenzae, including nontypeable (NT) H. influenzae. PD is involved in the pathogenesis of respiratory tract infections, in the context of which it has been shown to impair ciliary function in a human nasopharyngeal tissue culture model and to augment the capacity to cause otitis media in rats. A likely mecha

Old people in pain: A comparative study.

To investigate the prevalence of pain in older people (75+), compare those in pain to those without regarding demographics, social network, functional limitations, fatigue, sleeping problems, depressed mood and quality of life (QOL), and identify variables associated with pain, a cross-sectional, prospective survey was conducted in an age-stratified sample of 4,093 people aged 75–105 years old. Th

Broad-scale Increase in NPP Quantified for the African Sahel, 1982-1999

In association with a recently discovered greening trend in the Sahel, several interesting new perspectives have appeared in the literature regarding its climate and ecology. In this Letter, satellite data from 1982 to 1999 and a light use efficiency model are used to map net primary production (NPP) increases throughout the Sahel (total area of 1.13 x 10(13) m(2)). A patchy, east-west band of inc

Cheyne-Stokes respiration in patients hospitalised for heart failure

Background: Previous studies showing a strong relationship between Cheyne-Stokes respiration and the severity of left ventricular systolic dysfunction have usually been done in selected patient populations with lower age and a higher proportion of males than the "typical" in-hospital patient with heart failure. The purpose of the present study was test the strength of this relationship in unselect

Large tundra methane burst during onset of freezing.

Terrestrial wetland emissions are the largest single source of the greenhouse gas methane. Northern high-latitude wetlands contribute significantly to the overall methane emissions from wetlands, but the relative source distribution between tropical and high-latitude wetlands remains uncertain. As a result, not all the observed spatial and seasonal patterns of atmospheric methane concentrations ca

Methionine sulfoxidation of the chloroplast small heat shock protein and conformational changes in the oligomer

The small heat shock proteins (sHsps), which counteract heat and oxidative stress in an unknown way, belong to a protein family of sHsps and alpha-crystallins whose members form large oligomeric complexes. The chloroplast-localized sHsp, Hsp21, contains a conserved methionine- rich sequence, predicted to form an amphipatic helix with the methionines situated along one of its sides. Here, we report

Bridge splitting of trans-[PtCl2(C2H4)](2) by ethene using a simple combined NMR-UV/vis cell: Crystal and molecular structure of cis-[PtCl2(C2H4)(2)]

Bridge splitting of trans- [PtCl2(C2H4)](2) by C2H4 in chloroform yields trans-[PtCl2(C2H4)(2)] which slowly isomerises to cis[PtCl2(C2H4)(2)] (crystal structure reported); the bridge-splitting equilibrium constant was determined as 6.8 +/- 0.6 mol(-1) dm(3) by the use of a combined NMR tube/spectrophotometric cell, enabling NMR and UV/vis measurements on the same closed system. (C) 2006 Elsevier

Can the LR test be helpful in choosing the optimal lag order in the VAR model when information criteria suggest different lag orders?

The objective of this simulation study is to investigate whether the likelihood ratio (LR) test can pick the optimal lag order in the vector autoregressive model when the most applied information criteria (i.e. vector Schwarz-Bayesian, SBC and vector Hannan-Quinn, HQC) suggest two different lag orders. This lag-choosing procedure has been suggested by Hatemi-J (1999). The results based on the Mont

Inhalation of swine dust induces cytokine release in the upper and lower airways

In healthy subjects, acute inhalation of swine dust causes an influx of inflammatory cells into the airways and increased bronchial responsiveness. The exposure may also cause fever and generalized symptoms. It seems likely that proinflammatory cytokines are involved in the response to inhaled swine dust. Nasal and bronchoalveolar lavage (BAL) were performed before, and 7 and 24 h after the start

Computer Animated Relaxation Therapy in Children Between 7 and 13 Years with Tension-Type Headache: A Pilot Study

This pilot study evaluated the effect of computer animated relaxation therapy in children between 7 and 13 years with tension-type headache and the children's experiences with the therapy. The therapy consisted of an uncontrolled nine-session course in modified progressive relaxation therapy assisted by computer animated surface EMG provided from the trapezius muscles and with the physiotherapist

Mannan induces ROS-regulated, IL-17A-dependent psoriasis arthritis-like disease in mice.

Psoriasis (Ps) and psoriasis arthritis (PsA) are poorly understood common diseases, induced by unknown environmental factors, affecting skin and articular joints. A single i.p. exposure to mannan from Saccharomyces cerevisiae induced an acute inflammation in inbred mouse strains resembling human Ps and PsA-like disease, whereas multiple injections induced a relapsing disease. Exacerbation of disea

Cooling vests with phase change material packs: the effects of temperature gradient, mass, and covering area

Phase change material (PCM) absorbs or releases latent heat when it changes phases, making thermal-regulated clothing possible. The objective of this study was to quantify the relationships between PCM cooling rate and temperature gradient, mass, and covering area on a thermal manikin in a climatic chamber. Three melting temperatures (24, 28, 32 °C) of the PCMs, different mass, covering areas, and

Human Papillomavirus 16 E6 Antibodies in Individuals Without Diagnosed Cancer: A Pooled Analysis.

Background: The increasing incidence of oropharyngeal cancer in many developed countries has been attributed to human papillomavirus type 16 (HPV16) infections. Recently, HPV16 E6 serology has been identified as a promising early marker for oropharyngeal cancer. Therefore, characterization of HPV16 E6 seropositivity among individuals without cancer is warranted. Methods: 4,666 controls were pooled

Variation in allergen content over time of acrylates/methacrylates in patch test preparations

P>Background Acrylates/methacrylates are volatile substances. There might be a gradual decrease in acrylate/methacrylate allergen content over time in patch test preparations but this has not yet been documented. Objectives To determine the allergen content of acrylates/methacrylates in patch test preparations over time under different storage conditions. Methods Five acrylate/methacrylate allerge

EPR assessment of protein sites for incorporation of Gd(III) MRI contrast labels.

We have engineered apolipoprotein A-I (apoA-I), a major protein constituent of high-density lipoprotein (HDL), to contain DOTA-chelated Gd(III) as an MRI contrast agent for the purpose of imaging reconstituted HDL (rHDL) biodistribution, metabolism and regulation in vivo. This protein contrast agent was obtained by attaching the thiol-reactive Gd[MTS-ADO3A] label at Cys residues replaced at four d

Search for new phenomena in final states with large jet multiplicities and missing transverse momentum at root s=8 TeV proton-proton collisions using the ATLAS experiment

A search is presented for new particles decaying to large numbers (7 or more) of jets, with missing transverse momentum and no isolated electrons or muons. This analysis uses 20.3 fb(-1) of p p collision data at root s = 8 TeV collected by the ATLAS experiment at the Large Hadron Collider. The sensitivity of the search is enhanced by considering the number of b-tagged jets and the scalar sum of ma