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Age-related increase in wall stress of the human abdominal aorta: An in vivo study

Background: The regulation of wall stress in the abdominal aorta (AA) of humans might be of specific interest, because the AA is the most common site for aneurysm formation in which wall stress seems to be an important pathophysiological factor. We studied the age-related changes in wall stress of the AA in healthy subjects, with the common carotid artery (CCA) as a comparison. Methods. A total of

An Improved Procedure for the Synthesis of Bicyclo[2.2.2]octane- 2,6-dione

Conjugate addition of Meldrum's acid to 2-cyclohexenone followed by direct cyclization in PPA/acetic acid constitutes a shorter, more reproducible and higher yielding route to bicyclo[2.2.2]octane-2,6-dione than previous methods. The crude dione could be used as substrate for the baker's yeast reduction to (IR, 4S, 6S)-bicyclo[2.2.2]octane-6-ol-2-one.

Substance P relaxes rat bronchial smooth muscle via epithelial prostanoid synthesis

BACKGROUND: Substance P is present in bronchial nerve fibres. The physiological actions of substance P are mediated via tachykinin NK(1) receptors. Immunochemical studies have demonstrated tachykinin NK(1) receptors in the rat airway epithelium. OBJECTIVE: To elucidate how epithelial tachykinin NK(1) receptors affect smooth muscle response to substance P. METHODS: Contractile response of isolated

Towards ILBC speech coding at lower rates through a new formulation of the start state search

The Internet Low Bit-rate Coder (iLBC) has emerged as a candidate for Voice over Internet Protocol (VoIP) applications. By avoiding the inter-frame coding dependencies endemic to many speech coders such as those based on Code Excited Linear Prediction, iLBC is able to achieve superior robustness to packet loss. In addition to robustness to packet loss, a VoIP codec should possess the agility to ad

Local changes in cerebral energy metabolism due to brain retraction during routine neurosurgical procedures

Patients and Interventions. Tissue damage caused by brain retraction was evaluated utilizing intracerebral microdialysis in six patients operated on subfrontally for pituitary adenoma. The microdialysis probes (membrane length 10 mm, cut-off 20 kDalton) were placed in cerebral cortex beneath the brain retractor and perfused with Ringer solution at 0.3 mul/min. The microdialysis vials were changed

Replicated host-race formation in bogus yucca moths: genetic and ecological divergence of Prodoxus quinquepunctellus on yucca hosts

Goal: Assess host-race formation in certain moths by examining their genetic and ecological differentiation. Organisms: Stalk-feeding moths, Prodoxus quinquepunctellus, collected from sympatric populations of Yucca elata and Y rostrata in west Texas, USA. Results: Moths on the two yuccas differed significantly in mtDNA haplotype frequencies, emergence time, wing dot number, body size, and ovipos

Cartilage oligomeric matrix protein and thrombospondin 1. Purification from articular cartilage, electron microscopic structure, and chondrocyte binding

Cartilage oligomeric matrix protein (COMP) and thrombospondin 1 (TSP1) were purified in a native form from normal bovine articular cartilage. The key step in the purification scheme was selective extraction with EDTA-containing buffer. Final separation of these two molecules was achieved by heparin affinity chromatography. Particles viewed by electron microscopy after rotary shadowing and negative

Studies of vector tomography

Popular Abstract in Swedish Bakgrunden till den här avhandlingen är att man vill utveckla en ny mammografimetod, som utnyttjar ultraljud. När en tunn stråle av kontinuerligt ultraljud träffar en partikel, till exempel en blodkropp, som rör sig, så uppstår en reflektion. Frekvensen av den reflekterade signalen är inte densamma som för den utsända. Signalen har fått ett så kallat Dopplerskift, där fThe motivation to study the kind of problems appearing in this thesis has been ultrasound measurements of flows, from which velocity spectra along lines can be determined. These velocity spectra can mathematically be described by a new non-linear transform, here called the Doppler Spectral Transform (DST). The Doppler spectral transform has a very rich theory, into which some steps are taken here

Amino acid supplementation improves heterologous protein production by Saccharomyces cerevisiae in defined medium

Supplementation of a chemically defined medium with amino acids or succinate to improve heterologous xylanase production by a prototrophic Saccharomyces cerevisiae transformant was investigated. The corresponding xylanase production during growth on ethanol in batch culture and in glucose-limited chemostat culture were quantified, as the native ADH2 promoter regulating xylanase expression was dere

Agostic interaction in the methylidene metal dihydride complexes H2MCH2 (M = Y, Zr, Nb, Mo, Ru, Th, or U)

Multiconfigurational quantum chemical methods (complete active space self-consistent field (CASSCF)/second-order perturbation theory (CASPT2)) have been used to study the agostic interaction between the metal atom and H(C) in the methylidene metal dihydride complexes H2MCH2, where M is a second row transition metal or the actinide atoms Th or U. The geometry of some of these complexes is highly ir

An improved numerical method of calculating the striation thinning in static mixers

An improved method of calculating the rate of striation thinning for laminar flow in a static mixer has been developed. The shapes of the objects studied are reconstructed using elliptic Fourier descriptors, allowing discrimination between true changes in shape and noise due to discretization errors. The method also allows one to choose the level of complexity in the objects to be reconstructed wh

Effect of additives on swelling of covalent DNA gels

The volumetric response of polymer gels on cosolute addition depends on the interaction of the polymer with the cosolute and can be used as a simple and sensitive way of elucidating these interactions. Here we report on DNA networks, prepared by crosslinking double-stranded DNA with ethylene glycol diglycidyl ether (EGDE); these have been investigated with respect to their swelling in aqueous solu

Operator Interaction and Optimization in Control Systems

The two themes of this thesis are operator interaction and optimization, primarily with application to complex plants in the process industry. Four important aspects that should be considered in the control system design for such plants are identified; safety, performance, operator interaction and operator acceptance. In particular, operator acceptance is considered as an aspect of major importanc

Rashba effect at magnetic metal surfaces

Exchange-split two-dimensional electronic states at the magnetic Gd(0001) surface change their energy dispersion upon magnetization reversal owing to the Rashba effect. The Rashba parameter is found to be substantially enhanced and to change sign when an epitaxial metal-oxide surface layer is formed. The experimental observations are quantitatively described by ab initio calculations giving a deta

Glycemic and risk factor control in type 1 diabetes - Results from 13,612 patients in a national diabetes register

OBJECTIVE - This study was designed to investigate the clinical characteristics of a large type 1 diabetic population and to evaluate the degree of fulfillment of recently updated treatment goals. RESEARCH DESIGN AND METHODS - The Swedish National Diabetes Register was initiated in 1996 as a tool for quality assurance in diabetes care. A1C levels, treatment, and risk factors were analyzed in two c

Effects of long-term treatment with estrogen and progesterone on in vitro muscle responses of the female rabbit urinary bladder and urethra to autonomic drugs and nerve stimulation

Ovariectomized virginal rabbits were treated with either estrogen or progesterone for 4 to 6 months. In vitro responses of muscle strips of the bladder and circular urethra were examined. Estrogen resulted in bladder contractions in response to noradrenaline and phenylephrine, whereas these agonists were without effect or evoked weak relaxations in castrated animals (and normals). Estrogen also ca