Search results

Filter

Filetype

Your search for "*" yielded 534488 hits

Evidence of stacking-fault distribution along an InAs nanowire using micro-focused coherent X-ray diffraction

InAs nanowire samples grown by metal-organic chemical vapor deposition present a significant amount of wurtzite structure, while the zincblende lattice is known to be the stable crystal structure for the bulk material. The question of the wurtzite distribution in the sample is addressed using phase-sensitive coherent X-ray diffraction with a micro-focused beam at a synchrotron source. The simultan

Deglacial environmental changes on Isla de los Estados (54.4°S), southeastern Tierra del Fuego

The island of Isla de los Estados is situated at 54.5 degrees S, 64 degrees W, east of Argentinian Tierra del Fuego, and is located in a sensitive geographic position in relation to the zonal circulation between Antarctica and South America. Its terrestrial records of the last deglaciation, recording atmospheric conditions but within an oceanic setting, can help to clarify changes of regional circ

Phylogeography of field voles (Microtus agrestis) in Eurasia inferred from mitochondrial DNA sequences

In a distribution-wide phylogeographic survey of the field vole (Microtus agrestis), 75 specimens from 56 localities across Eurasia were examined for DNA sequence variation along the whole 1140 base pair (bp) mitochondrial (mt) cytochrome b gene. The species is subdivided into three main mtDNA phylogeographic groups - western, eastern and southern - with largely allopatric distributions. The weste

Future Production and Utilisation of Biomass in Sweden: Potentials and CO2 Mitigation

Swedish biomass production potential could be increased significantly if new production methods, such as optimised fertilisation, were to be used. Optimised fertilisation on 25% of Swedish forest land and the use of stem wood could almost double the biomass potential from forestry compared with no fertilisation, as both logging residues and large quantities of excess stem wood not needed for indus

Principles and Practices of Knowledge Creation: On the Organization of "Buzz" and "Pipelines" in Life Science Communities

This article links up with the debate in economic geography on "local buzz" and "global pipelines" as two distinct forms of interactive knowledge creation among firms and related actors and argues for a rethinking of the way social scientists should approach interactive knowledge creation. It highlights the importance of combining the insights from studies of clusters and innovation systems with a

Gastric ghrelin cell development is hampered and plasma ghrelin is reduced by delayed weaning in rats

The duration of breastfeeding has attracted much interest, as a prolonged period of breastfeeding has been shown to reduce the risk of developing obesity. The mechanism behind the reduced risk is, however, poorly understood. The novel hormone ghrelin augments appetite, promotes body. weight increase and increases adiposity. The majority of circulating ghrelin emanates from endocrine cells in the o

Critical levels of atmospheric pollution: criteria and concepts for operational modelling of mercury in forests and lake ecosystems.

Mercury (Hg) is regarded as a major environmental concern in many regions, traditionally because of high concentrations in freshwater fish, and now also because of potential toxic effects on soil microflora. The predominant source of Hg in most watersheds is atmospheric deposition, which has increased 2- to >20-fold over the past centuries. A promising approach for supporting current European effo

Gallium phosphide nanowire arrays and their possible application in cellular force investigations

The authors report the fabrication of gallium phosphide nanowire arrays that can be used for cellular force measurements. The nanowire positions are defined using electron beam lithography and the nanowires are grown using metal organic vapor phase epitaxy. By varying the nanowire diameter, length, and spacing from substrate to substrate, they can expect to probe cell forces over several orders of

The effect of thiopental on cerebral blood flow, and its relation to plasma concentration, during simulated induction of anaesthesia in a porcine model

The reversible effect of an induction dose of thiopental on the cerebral blood flow (CBF) was characterized by repeated 133Xe washout measurements during stable physiological conditions in anaesthetized pigs. A thiopental effect corresponding to induction of light and transient anaesthesia was confirmed by electroencephalography (EEG). The concentration (arterial plasma) -effect (-% CBF) relations

Determination of trace levels of dinitrophenolic compounds by microporous membrane liquid-liquid extraction in environmental water samples

A fast and simple hollow fibre-based microporous membrane liquid-liquid extraction (MMLLE) method is proposed for the determination of trace levels of dinitrophenolic compounds in water samples. The optimization step was performed using a three-variables Doehlert matrix design, involving the fibre length, the quantity of trioctylphosphine oxide (TOPO) in the acceptor phase and the extraction time.

Validation of a new automated method for analysis of gated-SPECT images

We recently presented a new method for quantification of CArdiac FUnction - denoted CAFU - as the first step in the development of an automated method for integrated interpretation of gated myocardial perfusion single photon emission computed tomography (SPECT) images. The aim of this study was to validate CAFU in the assessment of global and regional function of the left ventricle. Quantitative g

On the induction of cold acclimation in carrots (Daucus carota L.) and its influence on storage performance

We investigated the role of cold acclimation in carrot plants with respect to its influence on the storage performance of the harvested taproots. The induction of cold acclimation was followed in plants cultivated in a growth chamber under strict climate control and in taproots harvested from two separate field cultivations where the plants had been exposed to the natural variations in climate. Un

Embedding fragment ab initio model potentials in CASSCF/CASPT2 calculations of doped solids: Implementation and applications

In this article, we present a fragment model potential approach for the description of the crystalline environment as an extension of the use of embedding ab initio model potentials (AIMPs). The biggest limitation of the embedding AIMP method is the spherical nature of its model potentials. This poses problems as soon as the method is applied to crystals containing strongly covalently bonded struc

Factors related to frequent usage of the primary healthcare services in old age: findings from The Swedish National Study on Aging and Care

People aged 60 or more are the most frequent users of healthcare services. In this age range, however, both frequent and infrequent users can be found. Frequent users have high rates of illnesses. Previous research has found that the frequency may be influenced also by psychological and social factors. The aim of this study was to investigate to what degree such factors add to the explanation of d

Spectroscopic studies of random telegraph noise in InAs quantum dots in GaAs

We have observed and investigated random telegraph noise in the photoluminescence from InAs quantum dots in GaAs. The luminescence from a single quantum dot, exhibiting switching between two levels, has been spectrally resolved. The random telegraph noise is only observed in the presence of band filling. We find no spectral shift of the emission in the different states. It is only the intensity, m