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Long term measurements of aerosol optical properties at a primary forest site in Amazonia

A long term experiment was conducted in a primary forest area in Amazonia, with continuous in-situ measurements of aerosol optical properties between February 2008 and April 2011, comprising, to our knowledge, the longest database ever in the Amazon Basin. Two major classes of aerosol particles, with significantly different optical properties were identified: coarse mode predominant biogenic aeros

Multi-proxy analyses of a peat bog on Isla de los Estados, easternmost Tierra del Fuego: a unique record of the variable Southern Hemisphere Westerlies since the last deglaciation

We have analyzed an almost 14,000 year old peat sequence on the island of Isla de los Estados (55 degrees S. 64 degrees W), east of Tierra del Fuego, in the core of the Southern Hemisphere Westerlies. A multitude of methods have been used: high resolution C-14 dating; detailed lithologic descriptions including humification degree; loss on ignition; magnetic susceptibility; bulk density; pollen and

Non-Elliptic Quadratic Forms and Semiclassical Estimates for Non-selfadjoint Operators

We consider a class of pseudodifferential operators with a doubly characteristic point, where the quadratic part of the symbol fails to be elliptic but obeys an averaging assumption. Under suitable additional assumptions, semiclassical resolvent estimates are established, where the modulus of the spectral parameter is allowed to grow slightly more rapidly than the semiclassical parameter.

Airway hyperresponsiveness to methacholine, adenosine 5-monophosphate, mannitol, eucapnic voluntary hyperpnoea and field exercise challenge in elite cross-country skiers

Background Methacholine hyperresponsiveness is prevalent in elite athletes. Comparative studies have hitherto been limited to methacholine, eucapnic voluntary hyperpnoea and exercise. This study investigated airway responsiveness to these stimuli as well as to adenosine 5'-monophosphate (AMP) and mannitol, in 58 cross-country ski athletes. Methods Exhaled nitric oxide concentration (FENO), spirome

Humidity affects the performance of von Frey monofilaments

Background Assessment of tactile and nociceptive thresholds of the skin with calibrated polyamide monofilaments is an established testing method both in animal and in human research. It is known that changes in relative humidity may affect the physical properties of the monofilaments. As this effect has only been studied in very small diameter monofilaments, used in neonatal research, we therefore

Long-term cost-minimization analysis comparing laparoscopic with open (Lichtenstein) inguinal hernia repair

Background: Laparoscopic surgery has emerged as a new treatment modality for inguinal hernia repair. The aim of the present study was to analyse its long-term costs in relation to those of open repair. Methods: A randomized multicentre study comparing totally extraperitoneal laparoscopic repair (TEP) with open repair by the Lichtenstein procedure was performed on men with a primary inguinal hernia

Spectral information as an orientation cue in dung beetles

During the day, a non-uniform distribution of long and short wavelength light generates a colour gradient across the sky. This gradient could be used as a compass cue, particularly by animals such as dung beetles that rely primarily on celestial cues for orientation. Here, we tested if dung beetles can use spectral cues for orientation by presenting them with monochromatic (green and UV) light spo

Structural and functional differences between L-type calcium channels: crucial issues for future selective targeting

Within the family of voltage-gated calcium channels (VGCCs), L-type channels (L-VGCCs) represent a well-established therapeutic target for calcium channel blockers, which are widely used to treat hypertension and myocardial ischemia. L-VGCCs outside the cardiovascular system also control key physiological processes such as neuronal plasticity, sensory cell function (e.g. in the inner ear and retin

Mischaracterising density dependence biases estimated effects of coloured covariates on population dynamics

Environmental effects on population growth are often quantified by coupling environmental covariates with population time series, using statistical models that make particular assumptions about the shape of density dependence. We hypothesized that faulty assumptions about the shape of density dependence can bias estimated effect sizes of temporally autocorrelated covariates. We investigated the pr

New Ordovician-Silurian drill cores from the Siljan impact structure in central Sweden: an integral part of the Swedish Deep Drilling Program

New drill cores from the largest known impact structure in Europe, the relict of the Siljan meteorite crater, provide new possibilities to reconstruct Early Palaeozoic marine environments and ecosystems, and to document changes in sedimentary facies, sea level and palaeoclimate in Baltoscandia. The impact crater is an important target of the project "Concentric Impact Structures in the Palaeozoic"

Bioinspired covalently grafted Cu(II)-C protected amino acid complexes: selective catalysts in the epoxidation of cyclohexene

In this work, the syntheses of covalently grafted C-protected Cu(II)-amino acid (methylesters of l-histidine and l-cystine) uniform and mixed ligand complexes with two different amino acid esters are described using chloropropylated silica gel as the support. The conditions of the syntheses were systematically altered. The structural features of the substances obtained were studied by the Kjeldahl

alpha-Synuclein expression and Nrf2 deficiency cooperate to aggravate protein aggregation, neuronal death and inflammation in early-stage Parkinson's disease

Although -synuclein (-SYN) aggregation is a hallmark of sporadic and familial Parkinsons disease (PD), it is not known how it contributes to early events of PD pathogenesis such as oxidative and inflammatory stress. Here, we addressed this question in a new animal model based on stereotaxic delivery of an adeno-associated viral vector (rAAV) for expression of human -SYN in the ventral midbrain of

Swedish Female Hairdressers' Views on Their Work Environment - A Qualitative Study.

Objectives: Hairdressers have several work-related health hazards. Little is known of their strategies for the work environment. The aim of this study was to explore female hairdressers' own views on their physical, social and psychological work environment as possibilities of influencing it, implementation of their knowledge, financial impacts and how work-related symptoms affect their views. Met

Innate immunity and genetic determinants of urinary tract infection susceptibility.

Urinary tract infections (UTIs) are common, dangerous and interesting. Susceptible individuals experience multiple, often clustered episodes, and in a subset of patients, infections progress to acute pyelonephritis (APN), sometimes accompanied by uro-sepsis. Others develop asymptomatic bacteriuria (ABU). Here, we review the molecular basis for these differences, with the intention to distinguish e

Measurement of underlying event characteristics using charged particles in pp collisions at root s = 900 GeV and 7 TeV with the ATLAS detector

Measurements of charged particle distributions, sensitive to the underlying event, have been performed with the ATLAS detector at the LHC. The measurements are based on data collected using a minimum-bias trigger to select proton-proton collisions at center-of-mass energies of 900 GeV and 7 TeV. The "underlying event" is defined as those aspects of a hadronic interaction attributed not to the hard

Analysis of Mice Lacking the Heparin-Binding Splice Isoform of Platelet-Derived Growth Factor A

Platelet-derived growth factor A-chain (PDGF-A) exists in two evolutionarily conserved isoforms, PDGF-Along and PDGF-Ashort, generated by alternative RNA splicing. They differ by the presence (in PDGF-Along) or absence (in PDGF-Ashort) of a carboxyterminal heparin/heparan sulfate proteoglycan-binding motif. In mice, similar motifs present in other members of the PDGF and vascular endothelial growt