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Adaptive algorithms for constructing convex hulls and triangulations of polygonal chains

We study some fundamental computational geometry problems with the goal to exploit structure in input data that is given as a sequence C = (p(1), p(2), . . . ,p(n)) of points that are "almost sorted" in the sense that the polygonal chain they define has a possibly small number, k, of self-intersections, or the chain can be partitioned into a small number, X, of simple subchains. We give results th

Neutrophil recruitment, chemokine receptors, and resistance to mucosal infection

Neutrophil migration to infected mucosal sites involves a series of complex interactions with molecules in the lamina propria and at the epithelial barrier. Much attention has focussed on the vascular compartment and endothelial cells, but less is known about the molecular determinants of neutrophil behavior in the periphery. We have studied urinary tract infections (UTIs) to determine the events

Fluorescent leukotriene B-4: potential applications

Leukotriene B-4 (LTB4) is a potent lipid mediator of inflammation that acts primarily via a seven-transmembrane-spanning, G-protein-coupled receptor denoted BLT1. Here, we describe the synthesis and characterization of fluorescent analogs of LTB4 that are easy to produce, inexpensive, and without the disadvantages of a radioligand. Fluorescent LTB4 is useful for labeling LTB4 receptors for which n

Purification, characterization, and expression of rat intestinal alkaline sphingomyelinase.

Intestinal alkaline sphingomyelinase (SMase) has physiological roles in the digestion of sphingomyelin (SM) and clinical implications in colonic carcinogenesis. In the present work, the enzyme from rat has been purified 1,589-fold with 11% recovery by elution of the intestine with bile salt, precipitation of the proteins by acetone, and several types of chromatographies. Its molecular mass was 58

A metal binding site in the catalytic subunit of anaerobic ribonucleotide reductase.

A Zn(Cys)4 center has been found in the C-terminal region of the crystal structure of the anaerobic class III ribonucleotide reductase (RNR) from bacteriophage T4. The metal center is structurally related to the zinc ribbon motif and to rubredoxin and rubrerythrin. Mutant enzymes of the homologous RNR from Escherichia coli, in which the coordinating cysteines, conserved in almost all known class I

Severe inbreeding depression in a wild wolf (Canis lupus) population

The difficulty of obtaining pedigrees for wild populations has hampered the possibility of demonstrating inbreeding depression in nature. In a small, naturally restored, wild population of grey wolves in Scandinavia, founded in 1983, we constructed a pedigree for 24 of the 28 breeding pairs established in the period 1983-2002. Ancestry for the breeding animals was determined through a combination

Time to extinction in relation to mating system and type of density regulation in populations with two sexes

1. Population viability models usually consider only the female segment of the population. However, random variation in sex ratio as well as the mating system may also affect variation in fitness among females. Here we develop population models incorporating demographic stochasticity in both sexes. Furthermore, we consider the effects on the estimated time to extinction and whether density regulat

BAL fluid derived fibroblasts differ from biopsy derived fibroblasts in systemic sclerosis.

Growth of fibroblasts from bronchoalveolar lavage fluid (BALF) in patients with systemic sclerosis (SSc) has previously been described. The purpose of the present study was to characterise fibroblasts from BALF and bronchial biopsies from SSc patients with alveolitis and from controls, to analyse fibroblast proliferation, migration, stress fibres and proteoglycan production. BALF and bronchial bio

Influence of adhesins on the interaction of Escherichia coli with human phagocytes

The fitness between bacterial adhesins and target cell receptors, determining bacterial adherence to epithelial cells in urinary tract infections, was shown to influence also the interaction with human polymorphonuclear leukocytes (PMNL). Two sets of homogenic strains, constructed to express either, both, or none of the globotetraosylceramide-sensitive (GS) adhesins specific for globoseries glycol

Effects of duration of type 2 diabetes mellitus on insulin secretion.

Objective: To gain insight into the effects of duration of type 2 diabetes on insulin secretion in patients with type 2 diabetes mellitus. Methods: C-peptide concentrations were measured every 2 years before and after intravenous injection of 1 mg of glucagon in 89 patients with type 2 diabetes (51 men and 38 women) as part of the Rochester Diabetic Neuropathy Study in those subjects who particip

Permian plant macrofossils from Fossilryggen, Vestfjella, Dronning Maud Land

A low diversity plant macrofossil assemblage described from the northern section of Fossiryggen, Vestfiella, Dronning Maud Land, Antarctica, is dominated by matted leaf impressions of Glossopteris sp. cf. G communis Feistmantel and Glossopteris sp. cf. G spatulata Pant A Singh, and in situ finely branched Vertebraria indica Royle rootlets. Equisetalean stems, rhizomes and leaf whorls (Pkyllotheca

Estrogen receptor beta expression is associated with tamoxifen response in ER alpha-negative breast carcinoma

PURPOSE: Endocrine therapies, such as tamoxifen, are commonly given to most patients with estrogen receptor (ERalpha)-positive breast carcinoma but are not indicated for persons with ERalpha-negative cancer. The factors responsible for response to tamoxifen in 5% to 10% of patients with ERalpha-negative tumors are not clear. The aim of the present study was to elucidate the biology and prognostic

A description of health care provision and access to treatment for women with urinary incontinence in Europe - A five-country comparison

Background: Female urinary incontinence is a prevalent condition, but only about one-third of women seek treatment. Objectives: To describe the health care provision for women with urinary incontinence from a European perspective, selecting France, Germany, Spain, Sweden, and the United Kingdom as examples, and to investigate whether specific barriers for treatment exist. Methods: Available health

The Streptomyces rubiginosus xylose isomerase is missfolded when expressed in Saccharomyces cerevisiae.

The Streptomyces rubiginosus xylA gene was cloned and expressed in Saccharomyces cerevisiae. No xylose isomerase activity could be detected. The produced xylose isomerase protein was insoluble and could only be recovered from cell lysates by extraction with the detergent sodium dodecyl-sulfate. In contrast, expression of the xylA gene from Thermus thermophilus in the same host strain resulted in s

The precarious practice of forensic psychiatric risk assessments

The development of forensic psychiatric risk assessments is discussed from a clinical point of view using the example of Sweden. A central task in forensic psychiatry has traditionally been to identify dangerous, mentally disordered subjects considered to be prone to commit violent acts. Over time, "dangerousness" has been reworded into "risk". Nevertheless, such assessments have generally been ba

Fast correlation attacks based on turbo code techniques

This paper describes new methods for fast correlation attacks on stream ciphers, based on techniques used for constructing and decoding the by now famous turbo codes. The proposed algorithm consists of two parts, a preprocessing part and a decoding part. The preprocessing part identifies several parallel convolutional codes, embedded in the code generated by the LFSR, all sharing the same informat

NMR diffusometry and conductometry study of the host-guest association between beta-cyclodextrin and dodecane 1,12-bis(trimethylammonium bromide)

Surfactants form association complexes with cyclodextrins. In the present investigation we have used NMR-diffusometry and electrical conductivity to follow the interactions which take place between ss-cyclodextrm and a bolaform surfactant: dodecane 1, 1 2-bis(trimethylammonium bromide). Both H-1 NMR self-diffusion and conductometry data indicate the formation of a 1: 1 inclusion complex. Assuming