Sökresultat

Filtyp

Din sökning på "*" gav 529676 sökträffar

Factors controlling hydrochemical and trophic state variables in 86 shallow lakes in Europe

In order to disentangle the causes of variations in water chemistry among European shallow lakes, we performed standardised sampling programs in 86 lakes along a latitudinal gradient from southern Spain to northern Sweden. Lakes with an area of 0.1 to 27000 ha and mean depth of 0.4-5.6 m located in low to high altitudes were investigated within the EC project ECOFRAME 1-4 times during June-October

Catalyst-free nanowires with axial InxGa1-xAs/GaAs heterostructures

Self-catalyzed growth of axial InxGa1-xAs/GaAs heterostructures has been realized by molecular beam epitaxy. The growth of the wires is achieved from gallium/indium alloy droplets that are nucleated in situ. By variation of the In/Ga beam flux during the growth it was possible to vary the effective indium content up to x = 5%, as deduced from photoluminescence measurements. We have analyzed the de

Effects of propofol on isolated human pial arteries

BACKGROUND: The intravenous anaesthetic propofol has been reported to increase cerebral vascular resistance in vivo. The underlying mechanisms are not fully understood, but may include effects on metabolism and direct effects on the vascular smooth muscle. The present study was designed to evaluate the direct effects of propofol on human pial arteries. METHODS: We investigated the direct effect of

Retinal progenitor cell xenografts to the pig retina: immunological reactions.

We evaluated the host response to murine retinal progenitor cells (RPCs) following transplantation to the subretinal space (SRS) of the pig. RPCs from GFP mice were transplanted subretinally in 18 nonimmunosuppressed normal or laser-treated pigs. Evaluation of the SRS was performed on hematoxylin-cosin (H&E)-stained sections. Serum samples were taken from naive and RPC-grafted pigs and mouse-r

Wheelchair users and public transit : Eliciting ascriptions of comfort and safety

Transport policies often contain explicit goals for the travel quality of disabled passenger groups. Addressing the user perspective, focus group discussions with wheelchair-seated passengers (using bus transit and Special Transportation Services) were therefore held, in order to qualitatively explore perceived comfort and safety - two important quality factors. The comfort and safety constructs w

Guidelines for human papillomavirus DNA test requirements for primary cervical cancer screening in women 30 years and older

Given the strong etiologic link between high-risk HPV infection and cervical cancer high-risk HPV testing is now being considered as an alternative for cytology-based cervical cancer screening. Many test systems have been developed that can detect the broad spectrum of hrHPV types in one assay. However, for screening purposes the detection of high-risk HPV is not inherently useful unless it is inf

Vertebral fractures in late adolescence: a 27 to 47-year follow-up.

The long-term outcome of thoracic and lumbar fractures in late adolescence is sparsely described and it is unclear whether a fractured vertebral body in these years, as in young children, can be resituated in height. The purpose of this study was to in late adolescence determine the incidence, the long-term outcome and the modelling capacity in fractures of the thoracic and lumbar region. The inci

Histidine tag fusion increases expression levels of active recombinant amelogenin in Escherichia coli

Amelogenin is a dental enamel matrix protein involved in formation of dental enamel. In this study, we have expressed two different recombinant murine amelogenins in Escherichia coli: the untagged rM179, and the histidine tagged rp(H)M180, identical to rM179 except that it carries the additional N-terminal sequence MRGSHHHHHHGS. The effects of the histidine tag on expression levels, and on growth

Low-frequency and high-frequency changes in temperature and effective humidity during the Holocene in south-central Sweden: implications for atmospheric and oceanic forcings of climate

An integrated use of independent palaeoclimatological proxy techniques that reflect different components of the climate system provides a potential key for functional analysis of past climate changes. Here we report a 10,000 year quantitative record of annual mean temperature (T-ann), based on pollen-climate transfer functions and pollen-stratigraphical data from Lake Flarken, south-central Sweden

Kindling alters entorhinal cortex-hippocampal interaction by increased efficacy of presynaptic GABA(B) autoreceptors in layer III of the entorhinal cortex

We studied the effect of kindling, a model of temporal lobe epilepsy, on the frequency-dependent information transfer from the entorhinal cortex to the hippocampus in vitro. In control rats repetitive synaptic activation of layer III projection cells resulted in a frequency dependent depression of the synaptic transfer of action potentials to the hippocampus. One-to-two-days after kindling this ef

Postcollision interaction in noble gas clusters: Observation of differences in surface and bulk line shapes

The surface and bulk components of the x-ray photoelectron spectra of free noble gas clusters are shown to display differences in the influence of postcollision interaction between the photoelectron and the Auger electron on the spectral line shape; the bulk component is observed to be less affected than the surface and atomic parts of the spectra. A model for postcollision interaction in nonmetal

Elevated levels and distinct patterns of expression of A-type cyclins and their associated cyclin-dependent kinases in male germ cell tumors

Aberrant expression of several key regulators controlling the G1/S phase of the cell cycle has been implicated in human male germ cell tumorigenesis. Given the critical role of cyclin A2 at both the G1/S and G2/M transitions and the essential role for cyclin A1 in male germ cell development, our present study focused on the involvement of the A-type cyclins in the transformation and progression of

Environmental effects of ozone depletion and its interactions with climate

After the enthusiastic celebration of the 20th Anniversary of the Montreal Protocol on Substances that Deplete the Ozone Layer in 2007, the work for the protection of the ozone layer continues. The Environmental Effects Assessment Panel is one of the three expert panels within theMontreal Protocol. This “EEAP” deals with the increase of the UV irradiance on the Earth’s surface and its effects on h

Characterisation of dic(9;20)(p11-13;q11) in childhood B-cell precursor acute lymphoblastic leukaemia by tiling resolution array-based comparative genomic hybridisation reveals clustered breakpoints at 9p13.2 and 20q11.2

Although the dic(9;20)(p11-13;q11) is a recurrent chromosomal abnormality in paediatric B-cell precursor acute lymphoblastic leukaemia (BCP ALL), occurring in approximately 2% of the cases, its molecular genetic consequences have not been elucidated. In the present study, high-resolution genome-wide array-based comparative genomic hybridisation (array-CGH) and fluorescence in situ hybridisation (F

Protonation and charging of nanosized gibbsite (alpha-Al(OH)(3)) particles in aqueous suspension

Synthetic gibbsite was prepared and thoroughly characterized using X-ray diffraction, high-resolution transmission electron microscopy, atomic force microscopy, and Fourier transform infrared techniques. The protonation and charging of the particle surface(s) in 20 and 100 mM (Na)Cl ionic media were investigated using potentiometric titrations and zeta potential measurements. These measurements in

Multi-indices analysis of southern Scandinavian storminess 1780-2005 and links to interdecadal variations in the NW Europe-North Sea region

Extra-tropical cyclone frequency and intensity are Currently under intense scrutiny because of the destruction recent windstorms have brought to Europe, and because they are a major meridional heat transport mechanism that may respond to differential latitudinal warming trends. Several studies using reanalysis data covering the second half of the 20th century Suggest increasing storm intensity in

Regionauts: The Transformation of Cross-Border Regions in Scandinavia.

Many cross-border regions in Europe remain more political dreamscapes than examples of strong transnational integration.The development of the Öresund region through a bridge linking Copenhagen and eastern Denmark with Southern Sweden has been seen as a model for EU region building. Drawing on a multidisciplinary project, this article uses the Öresund case as a starting point, bringing in some con