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Development and characterization of silane antisticking layers on nickel-based stamps designed for nanoimprint lithography

In this study we will report on the development of a process to establish antisticking layers on nickel-based stamps, which are used in several industrial applications of nanoimprint lithography or related methods. The fluorinated alkyl silane films have been deposited onto different Ni-based stamp surfaces in order to minimize the adhesion tendency at the stamp/polymer interface. film thickness,

An experimental study of gastric stump carcinoma in Wistar rats

The risk of gastric stump carcinoma is increased 15-20 years after gastric resection for benign disease. Reflux of duodenal juice, bacterial overgrowth and formation of N-nitroso compounds are possible etiological factors. There is a geographical variation in the incidence of gastric cancer, possibly explained by differences in food intake. Experimentally it is possible to induce gastric stump car

Gender differences and determinants of aerobic fitness in children aged 8-11 years.

Previous studies of gender differences in maximum oxygen uptake have come to different conclusions. Limited data exists where the determinants of maximum oxygen uptake have been evaluated in a comprehensive manner. Thus, we examined 248 children (140 boys and 108 girls), aged 7.9-11.1 years. Body composition was determined by dual-energy X-ray absorptiometry, measured variables were total body fat

Human blastocysts for the development of embryonic stem cells

Establishment of human embryonic stem cells (hES) from surplus human IVF embryos has been successful when both fresh and frozen-thawed cleavage stage embryos have been cultured to the blastocyst stage. This study reports the characteristics of the starting material, the blastocysts, for hES cell lines that were first derived at the University of Gothenburg, Sahlgrenska University Hospital in 1999.

Obstructive sleep apnoea syndrome: current status

Introduction: Obstructive sleep apnoea syndrome (OSAS) is a prevalent condition that covaries with cardiovascular complications and most likely with arterial hypertension and diabetes mellitus. Objective: The present paper is a review of the current status of OSAS. Results: Definitions and diagnostic criteria as well as known risk factors, prevalence, symptoms, covariance with other diseases and c

Ga sublattice defects in (Ga,Mn)As: Thermodynamical and kinetic trends

We have used positron annihilation spectroscopy and infrared absorption measurements to study the Ga sublattice defects in epitaxial Ga1-xMnxAs with Mn content varying from 0% to 5%. We show that the Ga vacancy concentration decreases and As antisite concentration increases with increasing Mn content. This is in agreement with thermodynamical considerations for the electronic part of the formation

Morphology and molecular conformation in thin films of poly-gamma-methyl-L-glutamate at the air-water interface

The behavior of poly-gamma-methyl-L-glutamate (pMeE) at the air-water interface has been studied with the surface film balance technique. In addition, Langmuir-Blodgett (LB) films of pMeE deposited on mica and quartz have been studied by atomic force microscopy (AFM) and circular and linear dichroism (CD and LD) spectroscopy. Depending on the spreading solvent, pMeE displays strikingly different c

Reductive openings of benzylidene acetals. Kinetic studies of borane and alane activation by Lewis acids.

The reaction kinetics for a number of reductive openings of methyl 2,3-di-O-benzyl-4,6-O-benzylidene-alpha-d-glucopyranoside have been investigated. Openings to give free HO-6 (using BH(3).THF-AlCl(3)-THF or LiAlH(4)-AlCl(3)-Et(2)O) follow first order kinetics, while reactions yielding free HO-4 (using BH(3).NMe(3)-AlCl(3)-THF or BH(3).NMe(3)-BF(3).OEt(2)-THF) follow higher order kinetics. The add

Structure function relationships in the lymphatic system and implications for cancer biology

The lymphatic system, composed of lymphatic vessels, lymph, lymph nodes, and lymphocytes, is a distinctive vasculature (discontinuous basement membrane, open endothelial junctions, anchoring filaments, valves, and intrinsic contractility), different yet similar to the blood vasculature; an integral component of the plasma-tissue fluid-lymph circulation (the "blood-lymph loop"); and the center of t

Comparison of plasma and urinary levels of 2-hydroxyestrogen and 16 alpha-hydroxyestrogen metabolites

A modified ELISA assay for measurement of the two estrogen metabolites 2-hydroxyestrone (2OHE1) and 16 alpha-hydroxyestrone (16 alpha OHE1) in plasma and serum has been developed. Previously, these have only been measured in urine. It is not known how well the measurements of these metabolites in urine and plasma are correlated. The goal of this study was to compare urinary and plasma levels of 2O

One-Year Survival of Extremely Preterm Infants After Active Perinatal Care in Sweden

Context Up-to-date information on infant survival after extremely preterm birth is needed for assessing perinatal care services, clinical guidelines, and parental counseling. Objective To determine the 1-year survival in all infants born before 27 gestational weeks in Sweden during 2004-2007. Design, Setting, and Patients Population-based prospective observational study of extremely preterm infant

Two different approaches to model evolving directional properties at finite deformations

Two different approaches to modeling evolving anisotropic material behavior are investigated. The first approach models the evolution of the directionally dependent properties of the material in terms of evolution laws for the director vectors. In the second approach the evolution law for the plastic velocity gradient is enhanced by additional terms. It is shown that both approaches lead to an evo

Functional dissociation between proforms and mature forms of proteinase 3, azurocidin, and granzyme B in regulation of granulopoiesis.

We previously demonstrated that secreted proform(s) of the neutrophil serine protease PR3 (proteinase 3) can down-modulate the fraction of normal human colony-forming unit granulocyte-macrophage (CFU-GM) in S-phase, whereas PR3 extracted from mature neutrophils lacks this ability. The objective of this study was to characterize the structural and functional dissociation between secreted proforms a

Potential surfaces and delocalization of excitons in dimers

In the present work we will demonstrate that the nuclear dynamics have a strong influence on the delocalization of an exciton in a dimer, even if they do not effect the excitonic interaction. It will be shown that the internal nuclear conformation of the molecules forming the dimer depends critically on the delocalization of the exciton state in the dimer and vice versa. The resulting closed loop

Interaction between weak low frequency magnetic fields and cell membranes.

The question of whether very weak low frequency magnetic fields can affect biological systems, has attracted attention by many research groups for quite some time. Still, today, the theoretical possibility of such an interaction is often questioned and the site of interaction in the cell is unknown. In the present study, the influence of extremely low frequency (ELF) magnetic fields on the transpo

Expression profiling of Wilms tumors reveals new candidate genes for different clinical parameters

Wilms tumor is the most frequent renal neoplasm in children, but our understanding of its genetic basis is still limited. We performed cDNA microarray experiments using 63 primary Wilms tumors with the aim of detecting new candidate genes associated with malignancy grade and tumor progression. All tumors had received preoperative chemotherapy as mandated by the SIOP protocol, which sets this study

The influence of dietary fibre source and gender on the postprandial glucose and lipid response in healthy subjects.

BACKGROUND: Consumption of soluble dietary fibre is correlated with decreased postprandial glucose and insulin responses and hence has beneficial effects on the metabolic syndrome. AIM OF THE STUDY: To investigate the effects on postprandial glucose, insulin and triglyceride concentrations of meals enriched with soluble dietary fibres from oats, rye bran, sugar beet fibre or a mixture of these thr