Sökresultat

Filtyp

Din sökning på "*" gav 533385 sökträffar

Outwards migration for planets in stellar irradiated 3D discs

For the very first time we present 3D simulations of planets embedded in stellar irradiated discs. It is well known that thermal effects could reverse the direction of planetary migration from inwards to outwards, potentially saving planets in the inner, optically thick parts of the protoplanetary disc. When considering stellar irradiation in addition to viscous friction as a source of heating, th

Histamine H(4) receptor antagonism inhibits allergen-specific T-cell responses mediated by human dendritic cells.

Dendritic cells are potential targets in allergy therapy as they, under the influence of their microenvironment, regulate T-cell responses. Histamine has been shown to promote Th2 polarization by dendritic cells. However, neither the mechanism nor the functionality of the different histamine receptors in this process has been fully elucidated. The aim of the present study was to identify factors i

Study of interhalogens/silver trifluoromethanesulfonate as promoter systems for high-yielding sialylations

We have studied interhalogen/silver trifluoromethanesulfonate (IX/AgOTf) promoted glycosylations and found differences in the sensitivity of the formed oxocarbenium ions (e.g. from compounds with or without participating groups) toward halide nucleophiles. These differences can be explained using the HSAB theory. By applying this theory on sialylations, we increased the yield for a model reaction

Efficient asymmetric synthesis of an azasugar in water

An extremely efficient asymmetric synthesis of a pyrrolidine azasugar was completed in only four steps in water, without the use of protecting groups and in 60% overall yield from a simple, achiral bis-electrophile.

Production of vegetable oil in milk emulsions using membrane emulsification

The production of emulsions using milk as the continuous phase has a number of applications of interest from the food industry's point of view. In addition, producing an emulsion with a narrow drop size distribution is interesting since their increased stability could avoid Oswald ripening and creaming. Membrane emulsification is a novel technique which helps to obtain a narrower distribution comp

Impact of the peroxisome proliferator activated receptor-gamma coactivator-1 beta (PGC-1 beta) Ala203Pro polymorphism on in vivo metabolism, PGC-1 beta expression and fibre type composition in human skeletal muscle

Aims/hypothesis Peroxisome proliferator activated receptor-gamma coactivator-lp (PGC-1 beta, also known as PPARGCIB) expression is reduced in skeletal muscle from patients with type 2 diabetes mellitus and in elderly subjects. Ala203Pro, a common variant in the PGC-1 beta gene is associated with obesity. The aim of this study was to investigate whether the PGC-1 beta Ala203Pro polymorphism influen

Hepatic cirrhosis increases sensitivity of kidney to endotoxin in rats

BACKGROUND: Renal failure in cirrhotic patients is a severe complication and endotoxemia might be involved. We investigated the effect of endotoxin on renal function of cirrhotic rats and the potential protective role of N-acetylcysteine (NAC). MATERIAL/METHODS: Hepatic cirrhosis was generated in a rat model by carbon tetrachloride. Both cirrhotic and normal rats were insulted by endotoxin intrave

Identification of low-risk tumours in histological high-grade soft tissue sarcomas

In more than one-third of patients with a histological high-grade malignant soft tissue sarcoma metastasis develops despite local control of the primary tumour. Hence, adjuvant chemotherapy is increasingly used for these relatively chemoresistant tumours which requires improved prognostication to exclude low-risk patients from overtreatment. We assessed the value of stepwise prognostication in a s

Phosphorylation of DARPP-32 regulates breast cancer cell migration downstream of the receptor tyrosine kinase DDR1.

Cell migration plays a central role in processes such as development, wound healing and cancer metastasis. Here we describe a novel interaction between DDR1, a receptor tyrosine kinase activated by collagen, and the phosphoprotein DARPP-32 in mammary epithelial cells. DARPP-32 expression was readily detected in non-transformed mammary cell lines, but was strongly reduced or even absent in breast t

Direct electron transfer - A favorite electron route for cellobiose dehydrogenase (CDH) from Trametes villosa. Comparison with CDH from Phanerochaete chrysosporium

This paper presents some functional differences as well as similarities observed when comparing the newly discovered cellobiose dehydrogenase (CDH) from Trametes Villosa (T.v) with the well-characterized one from Phanerochaete chrysosporium (P.c.). The enzymes were physically adsorbed on spectrographic graphite electrodes placed in an amperometric flow through cell connected to a flow system. In t

A continuous-index hidden Markov jump process for modeling DNA copy number data.

The number of copies of DNA in human cells can be measured using array comparative genomic hybridization (aCGH), which provides intensity ratios of sample to reference DNA at genomic locations corresponding to probes on a microarray. In the present paper, we devise a statistical model, based on a latent continuous-index Markov jump process, that is aimed to capture certain features of aCGH data, i

Effects of dopamine on porcine myocardial action potentials and contractions at 37 degrees C and 32 degrees C

BACKGROUND: Little information exists on the effects of drugs with cardiovascular action in hypothermia, and some findings have indicated paradoxic effects of dopamine in this setting. As we have not found any data on the electrophysiologic and contractile effects of dopamine on the heart in hypothermia, we decided to study this in pig myocardium, since pigs have a cardiovascular system more simil

Stability and variability in the realism of confidence judgments over time, content domain, and gender

This study investigates the influence on the realism of confidence judgments of four different factors, the individual, the knowledge domain (crystallized and fluid intelligence), gender and cognitive style (Need-for-Cognition, NfC). Seventy-nine high-school students answered questions on word knowledge (WORD) and logical/spatial ability (DTK), both tests were administered on three occasions with

Modeling and control of a novel heat exchange reactor, the Open Plate Reactor

A new chemical reactor, the Open Plate Reactor, is being developed by Alfa Laval AB. It combines good mixing with high heat transfer capacity into one operation. With the new concept, highly exothermic reactions can be produced using more concentrated reactants. A nonlinear model of the reactor is derived and a control system is developed. For temperature control a cooling system is designed and e

Balance Control and Adaptation during Vibratory Perturbations in Middle-Aged and Elderly Humans.

The objective was to investigate if healthy elderly people respond and adapt differently to postural disturbances compared to middle-aged people. Thirty middle-aged (mean age 37.8 years, range 24–56 years) and forty healthy elderly subjects (mean age 74.6 years, range 66–88 years) were tested with posturography. Body sway was evoked by applying pseudorandom vibratory stimulation to the belly of th

Rapid early-Holocene environmental changes in northern Sweden based on studies of two varved lake-sediment sequences

Mineral magnetic, organic carbon and pollen studies of two varved Holocene lake-sediment sequences in the boreal forest of northern Sweden indicate that significant environmental changes took place between c. 6000 and 5700 BC. This interval is characterized by an increase in mineral-matter accumulation, which is a proxy for winter-snow accumulation, and a statistically significant decrease in tota