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C2-Symmetric Macrocyclic Carbohydrate/Amino Acid Hybrids through Copper(I)-Catalyzed Formation of 1,2,3-Triazoles

An efficient method was developed for the preparation of macrocyclic carbohydrate/amino acid hybrids by macrocyclization with copper(I)-catalyzed 1,2,3-triazole formation. Methyl 2-amino-6-azido-3,4-di-O-benzoyl-2,6-dideoxy--D-glucopyranoside was prepared and coupled to two different N-propiolyl dipeptides (propiolyl-Tyr-Tyr-OH and propiolyl-Arg(Mtr)-Tyr-OH) to obtain bifunctional molecules carryi

A traditional agroforestry system under threat: an analysis of the gum arabic market and cultivation in the Sudan

The main aim of this study is to review the environmental and socioeconomic sustainability of the gum arabic farming system in central Sudan. A further aim is to analyse some of the main factors influencing production in recent decades in order to understand the future trade potential and consequently the smallholder livelihood. The study shows that end-user imports of gum arabic have increased du

Role of chromoendoscopy in colon cancer surveillance in inflammatory bowel disease.

Inflammation in the intestine is a well-known risk factor for neoplastic changes in the mucosa. In fact, it has been shown that long-standing ulcerative colitis and colonic Crohn's disease have a significantly increased risk for developing colorectal cancer, although the estimates vary widely between studies. Conventional colonoscopy is effective in detecting polypoid changes in the mucosa. Howeve

Diesel fuel jet lift-off stabilization in the presence of laser-induced plasma ignition

The mechanisms affecting lift-off stabilization at diesel conditions were investigated by laser-igniting a diesel fuel jet upstream of its natural lift-off position. Single-nozzle fuel sprays penetrating into all optically accessible constant-volume chamber were ignited using laser-induced plasma formation both prior to natural autoignition or after a quasi-steady lift-off length was established.

Four modes of adhesion are used during Helicobacter pylori binding to human mucins in the oral and gastric niches

Background: Helicobacter pylori causes peptic ulcer disease and gastric cancer, and the oral cavity is likely to serve as a reservoir for this pathogen. We investigated the binding of H. pylori to the mucins covering the mucosal surfaces in the niches along the oral to gastric infection route and during gastric disease and modeled the outcome of these interactions. Materials and Methods: A panel o

Species-specificity of Neisseria gonorrhoeae infection: Do human complement regulators contribute?

Neisseria gonorrhoeae is the causative agent of gonorrhea, a disease restricted to humans. Complement forms a key arm of the innate immune system that combats gonococcal infections. N. gonorrhoeae uses its outer membrane porin (Por) molecules to bind complement clown-regulatory proteins, C4b-binding protein (C4BP) and factor H (M), to evade killing by human complement. In addition, sialylation of

Regulation of tissue factor-induced signaling by endogenous and recombinant tissue factor pathway inhibitor 1

Tissue factor (TF) triggers upstream coagulation signaling via the activation of protease-activated receptors (PARs) of relevance for inflammation and angiogenesis. TF pathway inhibitor 1 (TFPI-1) is the physiologic inhibitor of TF-initiated coagulation, but its role in regulating TF signaling is poorly understood. Here, we demonstrate that endogenous, endothelial cell-expressed TFPI-1 controls TF

A Long-Term Perspective on Person-Environment Fit and ADL Dependence Among Older Swedish Adults.

Purpose: This study described person–environment (P–E) fit and activities of daily living (ADLs) among older adults, and it explored the relationship between P–E fit and ADL dependence, testing Lawton's docility hypothesis at two points in time. Design and Methods: From a random sample of individuals aged 75–84 living in a Swedish municipality, 72 persons were available for baseline and follow-up

Energy transport in one-dimensional thermoelectric systems

The efficiency of thermoelectric power generators and the coefficient of performance of thermoelectric refrigerators increase rapidly in the region of small ZT, and then level off to a flat curve in the region of large ZT, where ZT is the figure of merit. Therefore, simply because one-dimensional thermoelectric materials have high ZT predicted theoretically does not imply that efficient thermoelec

Surface integrated dipole arrays with tapered resistive edge sheets

The performance of antenna arrays can be severely degraded by edge diffraction and reflections of surface waves from the edges. Here, it is shown that tapered resistive sheets can reduce the edge diffraction for surface integrated dipole arrays. It is observed that the monostatic RCS and the oscillations in the induced voltages of the receiving antenna are reduced.

Humoral immune response to citrullinated collagen type II determinants in early rheumatoid arthritis

Collagen type II (CII) is a relevant joint-specific autoantigen in the pathogenesis of rheumatoid arthritis (RA). Whereas the reasons for the breakage of self tolerance to this major cartilage component are still enigmatic, T cell responses to glycosylated CII determinants in RA patients indicate that post-translational modifications play a role. Since the conversion of arginine into citrulline by

Role of eicosanoids in airflow obstruction and airway plasma exudation induced by trimellitic anhydride-conjugate in guinea-pigs 3 and 8 weeks after sensitization

Trimellitic anhydride (TMA) is a low molecular weight chemical which can cause occupational asthma. We studied the role of eicosanoids in airway responses to TMA at different times after sensitization in actively sensitized guinea-pigs. Sensitization was performed by two intradermal injections of free TMA (0.1 ml of 0.3% TMA in corn oil). At 3 and 8 weeks after sensitization, the guinea-pigs were

Breast reductions: what to do with all the tissue specimens?

In order to find some guidelines for adequate examination of the often very large amount of tissue removed at reduction mammoplasties, a thorough macro- and microscopic study of a total of 400 specimens from 200 consecutive cases of bilateral breast reductions was done. The majority of patients were younger than 30 years of age. In these cases no abnormalities were found and a thorough macroscopic

Analytical approach for the Lucas-Washburn equation

Porous media can be characterized by studying the kinetics of liquid rise within the pore spaces. Although porous media generally have a complex structure, they can be modeled as a single, vertical capillary or as an assembly of such capillaries. The main difficulties lie in separately estimating the effective mean radius of the capillaries and the contact angle between the liquid and the pore. In

Ectomycorrhizal mycelial species composition in apatite amended and non-amended mesh bags buried in a phosphorus-poor spruce forest.

We studied the effect of apatite amendment on ectomycorrhizal (EM) mycelial biomass production and species composition in a phosphorus-poor spruce forest using sand-filled mesh bags. Control and apatite-amended bags were buried in pairs in the lower part of the organic horizon for one growth season. DNA extraction, PCR of the ITS region, cloning and random sequencing were used to examine the funga

Career concerns, contracts, and effort distortions

A two-period, career-concerns model with symmetric information but uncertainty about each worker's ability is analyzed. Contracts are unobservable, but incomes are observable. It is shown that effort is distorted upward by contracts being unobservable and that the distortion depends positively on turnover.

Cerebral blood volume (CBV) in humans during normo- and hypocapnia: influence of nitrous oxide (N(2)O)

BACKGROUND: It is generally argued that variations in cerebral blood flow create concomitant changes in the cerebral blood volume (CBV). Because nitrous oxide (N(2)O) inhalation both increases cerebral blood flow and may increase intracranial pressure, it is reasonable to assume that N(2)O acts as a general vasodilatator in cerebral vessels both on the arterial and on the venous side. The aim of t

No association of the IRS1 and PAX4 genes with type I diabetes

To reassess earlier suggested type I diabetes (T1D) associations of the insulin receptor substrate 1 (IRS1) and the paired domain 4 gene (PAX4) genes, the Type I Diabetes Genetics Consortium (T1DGC) evaluated single-nucleotide polymorphisms (SNPs) covering the two genomic regions. Sixteen SNPs were evaluated for IRS1 and 10 for PAX4. Both genes are biological candidate genes for T1D. Genotyping wa