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Disentangling the effects of climate and people on Sahel vegetation dynamics

The Sahel belt of Africa has been the focus of intensive scientific research since the 1960s, spurred on by the chronic vulnerability of its population to recurring drought and the threat of long-term land degradation. But satellite sensors have recently shown that much of the region has experienced significant increases in photosynthetic activity since the early 1980s, thus re-energizing long-sta

A revised geochronology for the Blekinge Province, southern Sweden

Zircon grains from nine samples of metavolcanic rocks, gneisses, granitoids and migmatites from the Blekinge Province in southeasternmost Sweden have been dated by U-Pb using ion microprobe. The results suggest that most of the Blekinge bedrock was formed within a narrow time interval of 1.77-1.75 Ga, including the Vastana supracrustal formation and 'coastal gneisses' previously dated to c. 1.70 G

Sea surface temperatures and ice rafting in the Holocene North Atlantic: climate influences on Northern Europe and Greenland

The oceanographic conditions in the high-latitude North Atlantic ocean during the Holocene were reconstructed through analyses of sea surface temperature (SST; alkenone unsaturation ratios) and ice rafting (mineralogy and grain size) from two sediment sequences, one recovered from the Reykjanes Ridge at 59degreesN and the other from the Norwegian Sea at 68degreesN. Comparison of our records to pub

Endothelium-specific ablation of PDGFB leads to pericyte loss and glomerular, cardiac and placental abnormalities

Platelet-derived growth factor-B (PDGFB) is necessary for normal cardiovascular development, but the relative importance of different cellular sources of PDGFB has not been established. Using Cre-lox techniques, we show here that genetic ablation of Pdgfb in endothelial cells leads to impaired recruitment of pericytes to blood vessels. The endothelium-restricted Pdgfb knockout mutants also develop

Shielded and unshielded geometries in the search for orphan sources.

A car-borne NaI(TI) spectrometric system was used together with a Cs-137 source to obtain realistic data in the search for unshielded and semi-shielded orphan sources. The potassium-stripped counts (PSC) method was used to estimate the influence by the shielding on the detection ability. A reduction of about 5% in the critical distance was obtained for the semi-shielded source. A curve fitting met

Effects of intranasal TNFalpha on granulocyte recruitment and activity in healthy subjects and patients with allergic rhinitis.

BACKGROUND: TNFalpha may contribute to the pathophysiology of airway inflammation. For example, we have recently shown that nasal administration of TNFalpha produces late phase co-appearance of granulocyte and plasma exudation markers on the mucosal surface. The objective of the present study was to examine indices of granulocyte presence and activity in response to intranasal TNFalpha challenge.

Protection of neutralization epitopes in the V3 loop of oligomeric human immunodeficiency virus type I glycoprotein 120 by N-linked oligosaccharides in the V1 region

The V3 region of the human immunodeficiency virus type 1 envelope protein gp120 constitutes a potential neutralization target, but the oligosaccharide of one conserved N-glycosylation site in this region protects it from neutralizing antibodies. Here, we determined whether N-linked glycans of other gp120 domains were also involved in protection of V3 neutralization epitopes. Two molecular clones o

Initial Characterization of Ethyl(hydroxyethyl) Cellulose Using Enzymic Degradation and Chromatographic Methods

Two different ethyl(hydroxyethyl) cellulose (EHEC) samples were characterized by size-exclusion chromatography (SEC) with multiangle light scattering (MALS) detection and high-performance anion-exchange chromatography (HPAEC) with pulsed amperometric detection (PAD). The aim of the study was to investigate the molar mass distribution and the heterogeneity of the substituent distribution, factors t

Predicting Long-Term Cognitive Outcome with New Regression Models in Donepezil-Treated Alzheimer Patients in a Naturalistic Setting.

Background/Aims: To build and analyze regression models predicting (1) the long-term cognitive outcome in donepezil-treated patients with Alzheimer's disease, and (2) the short-term (6 months) cognitive impact of treatment depending on cognitive severity at baseline. Methods: The Swedish Alzheimer Treatment Study (SATS) is an open-label, non-randomized, 3-year, multicentre study in a routine clini

Symmetry of spin transport in two-terminal waveguides with a spin-orbital interaction and magnetic field modulations

We analyze symmetries of spin transport in two-terminal quantum waveguide structures with Rashba spin-orbit coupling and magnetic field modulations. Constraints, imposed by the device structure, on the spin polarization of the transmitted electron beam from the waveguide devices are derived. The results are expected to provide accuracy tests for experimental measurements and numerical calculations

Performance measures of implant antennas

Modern electronic medical implants have reached a high degree of complexity. This has increased the demands on the communication link with the implant, both regarding the bandwidth and the communication distance. A medical communication system at RF frequencies has been standardised, the Medical Implant Communication System (MICS), which use a frequency allocation of 402 - 405 MHz. This frequency

The starling mating system as an outcome of the sexual conflict

Many bird species demonstrate a variable mating system, with some males being monogamously mated and other males able to attract more than one mate. This variation in avian mating systems is often explained in terms of potential costs of sharing breeding partners and compensation for such costs. However, whenever there is a difference in the optimal mating system for males and females, a sexual co

Antagonism of rat beta -cell voltage-dependent K+ currents by exendin-4 requires dual activation of the cAMP/PKA and PI3 kinase signalling pathways.

Antagonism of voltage-dependent K+ (Kv) currents in pancreatic {beta}-cells may contribute to the ability of glucagon-like peptide-1 (GLP-1) to stimulate insulin secretion. The mechanism and signaling pathway regulating these currents in rat {beta}-cells were investigated using the GLP-1 receptor agonist exendin 4. Inhibition of Kv currents resulted from a 20-mV leftward shift in the voltage depen

The use of language in understanding subject matter

Abstract in UndeterminedEmpirical results show that frequently the meaning of expressions used by students in expressing their understanding of subject matter does not correspond to the meaning of those expressions in the subject matter theory that the students are expected to learn. There is also often a lack of identity of meaning between the same students' use of the same expression from one us

From gamma-carboxy-glutamate to protein C.

The story I shall recount started in 1969, when I was given the opportunity to join the Department of Clinical Chemistry at the University Hospital in Malmo. I had just finished medical school at the university in the neighboring town of Lund. Parallel to pursuing my medical studies I had spent some time in the Department of Biochemistry. I did not know much about biochemistry, but it was enough f

Calpain inhibitors delay injury-induced apoptosis in adult mouse spinal cord motor neurons

Here, we investigated the effect of calpain inhibitors on apoptosis in organotypic adult spinal cord slices from mice. An increase in calpain I immunoreactivity was found in the nuclei of motor neurons from slices cultured for 30 min. After 4 h, the immunopositive motor neurons exhibited apoptotic changes including nuclear and chromatin condensation. Eight hours after excision, most motor neurons

Correlation between clinicopathological features and karyotype in 100 cartilaginous and chordoid tumours. A report from the Chromosomes and Morphology (CHAMP) Collaborative Study Group

The evaluation of chondroid lesions requires full integration of clinical, radiographic, and pathological data; tumour typing is often a challenge for the diagnostic pathologist. Although a variety of chromosomal abnormalities have been documented in chondroid lesions, the potential usefulness of cytogenetic analysis remains unclear. This study has critically reviewed and analysed 117 karyotyped s

Black box for constant-time insertion in priority queues

We present a simple black box that takes a priority queue Q which supports find-min, insert, and delete in x-time at most t. Here x-time may be worst-case, expected, or amortized. The black-box transforms Q into a priority queue Q* that supports find-min in constant time, insert in constant x-time, and delete in x-time O(t). Moreover, if Q supports dec-key in constant time, then so does Q*.