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Why are estimates of global terrestrial isoprene emissions so similar (and why is this not so for monoterpenes)?

Emissions of biogenic volatile organic compounds (BVOC) are a chief uncertainty in calculating the burdens of important atmospheric compounds like tropospheric ozone or secondary organic aerosol, reflecting either imperfect chemical oxidation mechanisms or unreliable emission estimates, or both. To provide a starting point for a more systematic discussion we review here global isoprene and monoter

Early amniocentesis and congenital foot deformities

Objective: Several studies have shown an increased risk of congenital foot derformities after early amniocentesis. These studies have comprised amniocenteses performed before 13 completed gestational weeks. In this study, the risk of foot deformities after amniocentesis performed at 12-14 completed gestational weeks was determined. Methods: 3,469 genetic amniocenteses in singleton pregnancies perf

Combined eyetracking and keystroke-logging methods for studying cognitive processes in text production.

Writers typically spend a certain proportion of time looking back over the text that they have written. This is likely to serve a number of different functions, which are currently poorly understood. In this article, we present two systems, ScriptLog+ TimeLine and EyeWrite, that adopt different and complementary approaches to exploring this activity by collecting and analyzing combined eye movemen

Dipping and variability of blood pressure and heart rate at night are heritable traits.

Background: Blunted nocturnal blood pressure dipping (NBPD) as well as high variability in blood pressure (BPV) and low variability in heart rate (HRV), are associated with increased cardiovascular morbidity and mortality. The aim of this study was to determine whether these traits are heritable. Methods: We studied 260 healthy siblings without antihypertensive drugs from 118 Swedish families. The

Stochastic noise approach to traffic flow modeling

Traffic flow states are described as resulting from a stochastically driven system. Vehicles advance based on the energy profile of their surrounding traffic. We create a stochastic process generated from an ergodicity satisfying Markov chain whose system dynamics sample from the Gibbs distribution. Specifically, we employ Arrhenius microscopic dynamics in order to also capture non-equilibrium be

Phenotypic correlates of variation at the Clock gene in a wild blue tit population: evidence for a role in seasonal timing of reproduction

The timing of reproduction in birds varies considerably within populations and is often under strong natural selection. Individual timing within years is dependent on a range of environmental factors in addition to having an additive genetic basis. In vertebrates, an increasing amount is known about the molecular basis for variation in biological timing. The Clock gene includes a variable poly-glu

Design of recombinant antibody microarrays for serum protein profiling: Targeting of complement proteins

Antibody-based microarrays is a novel technology with great promise for high-throughput proteomics. The process of designing high-performing arrays has, however, turned out to be challenging. Here, we have designed the next generation of a human recombinant scFv antibody microarray platform for protein expression profiling of nonfractionated biotinylated human plasma and serum proteomes. The setup

Outflow facility in the monkey eye: effects of calcitonin gene-related peptide, cholecystokinin, galanin, substance P and capsaicin

A study in cats has shown that intracameral injection of calcitonin gene-related peptide (CGRP) increases the outflow facility by four- to fivefold concomitant with a decrease in intra-ocular pressure (IOP). Since there are great differences in the anatomy of the aqueous outflow routes between cats and primates, we have examined the effects of CGRP in the cynomolgus monkey. The possible influence

Subgroup Analyses in Randomized Controlled Trials: The Need for Risk Stratification in Kidney Transplantation

Although randomized controlled trials (RCT) are the gold standard for establishing causation in clinical research, their aggregated results can be misleading when applied to individual patients. A treatment may be beneficial in some patients, but its harms may outweigh benefits in others. While conventional one-variable-at-a-time subgroup analyses have well-known limitations, multivariable risk-ba

Newborn human brain identifies repeated auditory feature conjunctions of low sequential probability

Natural environments are usually composed of multiple sources for sounds. The sounds might physically differ from one another only as feature conjunctions, and several of them might occur repeatedly in the short term. Nevertheless, the detection of rare sounds requires the identification of the repeated ones. Adults have some limited ability to effortlessly identify repeated sounds in such acousti

Neuropathology of white matter lesions in vascular cognitive impairment.

The white matter is an important locus for tissue damage in vascular cognitive impairment and white matter lesions often dominate over gray matter changes. The spectrum of ischemic white matter lesions histopathologically represents focal and diffuse lesions, the most common form being the combination of both, in varying proportions. In the combined pathology, the diffuse lesion represents a gradi

Seed set differs in relation to pollen and nectar foraging flower visitors in an insect-pollinated herb

Assessing the relative contributions to seed sets of each of a plant species' floral visitors provides an indication of the relative influence of these visitors on the plants' reproductive success. In this study we compared the seed set of the gynodioecious Knautia arvensis (Dipsacaceae) in 49 local plant populations in two regions of southern Sweden. We measured the seed set for hermaphroditic an

The middle Cambrian cosmopolitan key species Lejopyge laevigata and its biozone: new data from Sweden

The middle Cambrian Lejopyge laevigata Zone is poorly exposed in Scandinavia. Both this zone, however, and the succeeding Agnostus pisiformis Zone are well exposed at a classic locality at Gudhem, Vastergotland, south-central Sweden. The sequences consist of finely laminated alum shale with scattered stinkstone (orsten) lenses. Three measured and sampled sections yielded a diverse fossil fauna, do

Dispersion in Ice-Covered Lakes

Dispersion studies in three ice-covered lakes are presented. One of the lakes has a large river through-flow. In the other two lakes, small seiche-induced currents are generated through wind action on the ice cover. Dispersion coefficients are computed from five dye experiments lasting from ½ day to 16 days. These coefficients are related to measured current velocities. The turbulence in the river

Poly(3-hydroxybutyrate) biosynthesis in the biofilm of Alcaligenes eutrophus, using glucose enzymatically released from pulp fiber sludge

Glucose, enzymatically released from pulp fiber sludge, was combined with inorganic salts and used as a growth medium for Alcaligenes eutrophus, a gram-negative strain producing poly (3-hydroxybutyrate) (PHB). By controlling the concentrations of the inorganic salts in the growth medium, almost 78% of the cell mass was converted to pure PHB. Efforts were made to find conditions for bacterial growt

Conservation of seed-dispersing migrant birds in Mediterranean habitats: Shedding light on patterns to preserve processes

Migratory frugivorous birds disperse the seeds of many plant species, forming mutualistic associations that render frugivores a priority for conservation in many habitats worldwide. We analysed the distribution of seed-dispersing frugivorous passerines in southern Spain, which is an important area for the conservation of European birds during winter. Frugivorous birds showed similar regional abund

Means for STI prevention--how are they applied and how effective are they?

The present communication concerns factors, the application of which may contribute to reduce the transfer rate of sexually transmitted infections (STIs), including geomedical aspects. The factors elaborated on are, e.g. maternal health care, sexual education early in life, health prevention programmes and sexual risk reduction counselling of commercial sex workers, screening activities as well as

Holocene changes in atmospheric circulation recorded in the oxygen-isotope stratigraphy of lacustrine carbonates from northern Sweden

The oxygen-isotope composition of local precipitation (delta(18)O(P)) is reconstructed from carbonate lake-sediment components in a sediment core covering the last 10000 calendar years from Lake Tibetanus, a small, hydrologically open, groundwater-fed take in the Abisko area, northern Sweden. Comparison of the delta(18)O(P) history with a pollen-based palaeotemperature record from the same core cl