Search results

Filter

Filetype

Your search for "*" yielded 532180 hits

Exploration of conformational flexibility and hydrogen bonding of xylosides in different solvents, as a model system for enzyme active site interactions

The predominantly populated conformation of carbohydrates in solution does not necessarily represent the biologically active species; rather, any conformer accessible without too large an energy penalty may be present in a biological pathway. Thus, the conformational preferences of a naphthyl xyloside, which initiates in vivo synthesis of antiproliferative glycosaminoglycans, have been studied by

Molecular structure of citric acid cross-linked starch films

The effect of citric acid (CA) on starch films has been examined. A new method to detect cross-linking of starch by CA in solution-cast films by molecular weight measurements is described. Furthermore, we managed to distinguished between free, mono- and di-esterified CA and quantify di-ester content within starch films by using a modification in the method of complexometric titration with copper(I

Binding and elution behavior of small deoxyribonucleic acid fragments on a strong anion-exchanger multimodal chromatography resin.

The separation behavior of small single-stranded from double-stranded DNA molecules has been determined on a multimodal (mixed-mode) chromatography system. The resin used is a strong anion exchanger which also modulates hydrophobic recognition. The intrinsic differences between single- and double-stranded DNAs concerning charge, hydrophobicity and three-dimensional structure render this form of MM

From Learning Companions to Testing Companions Experience with a Teachable Agent Motivates Students' Performance on Summative Tests

In three quasi-experimental studies, we investigated the effects of placing a Teachable Agent (TA) from a math game in a digital summative test. We hypothesized that the TA would affect test performance, even without actual "teachability", by social influence on the test situation. In Study 1 (N=47), students did a pretest, played the math game for seven weeks, and did a posttest either with or wi

Incretin Effect after Oral Amino Acid Ingestion in Humans.

Context: The incretin effect is the augmented insulin secretion by oral versus intravenous glucose at matching glucose levels. We previously demonstrated an augmented insulin secretion when fat is given orally rather than intravenously, suggesting an incretin effect also after fat. However, whether there is an incretin effect is also present after amino acid ingestion is not known. Objective: To e

Evolution of CuI/Graphene/Ni(111) System during Vacuum Annealing

We present a combined core-level spectroscopy and low-energy electron diffraction study of the evolution of thin CuI layers on graphene/Ni(111) during annealing. It has been found that the annealing of the CuI/graphene/Ni(111) system up to 160 degrees C results in the formation of an ordered CuI overlayer with a (root 3 x root 3) R30 degrees structure on top of the graphene surface. At annealing t

Secular Trends in Swedish Hip Fractures 1987-2002: Birth Cohort and Period Effects.

BACKGROUND: Recently, a leveling off in hip-fracture incidence has been reported in several settings, but the annual number is nonetheless predicted to increase due to the growing elderly population. METHODS: Using Swedish national data for 1987-2002 for all inpatients 50 years or older, we examined the annual number and incidence of hip fractures and explored age, period, and cohort effects. Ag

Velocity and abundance precisions for future high-resolution spectroscopic surveys: A study for 4MOST

In preparation for future, large-scale, multi-object, high-resolution spectroscopic surveys of the Galaxy, we present a series of tests of the precision in radial velocity and chemical abundances that any such project can achieve at a 4 m class telescope. We briefly discuss a number of science cases that aim at studying the chemo-dynamical history of the major Galactic components (bulge, thin and

Local inhibition of ornithine decarboxylase reduces vascular stenosis in a murine model of carotid injury

Objectives: Polyamines are organic polycations playing an essential role in cell proliferation and differentiation, as well as in cell contractility, migration and apoptosis. These processes are known to contribute to restenosis, a pathophysiological process often occurring in patients submitted to revascularization procedures. We aimed to test the effect of alpha-difluoromethylornithine (DFMO), a

Coffee and tea consumption, genotype- based CYP1A2 and NAT2 activity and colorectal cancer risk- Results from the EPIC cohort study

Coffee and tea contain numerous antimutagenic and antioxidant components and high levels of caffeine that may protect against colorectal cancer (CRC). We investigated the association between coffee and tea consumption and CRC risk and studied potential effect modification by CYP1A2 and NAT2 genotypes, enzymes involved in the metabolization of caffeine. Data from 477,071 participants (70.2% female)

The EU's role in climate change negotiations: from leader to 'leadiator'

We start with two puzzles: first, how to explain the European Union (EU)'s decline as a climate change leader at the Copenhagen summit? Second, how to understand the partial revival of its leadership position at the Durban climate summit? We advance a twofold explanation, focusing on changes in relative power relations among major powers but also on negotiation strategies and coalition building. I

Determination of bile acids by hollow fibre liquid-phase microextraction coupled with gas chromatography.

A method based on hollow-fibre liquid phase microextraction combined with gas chromatography was developed for determination of specific bile acids in caecal materials of rats. Nine unconjugated bile acids, including the primary bile acids (cholic acid, chenodeoxycholic acid and α-muricholic acid) and the secondary bile acids (lithocholic acid, deoxycholic acid, ursodeoxycholic acid, hyodeoxycholi