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Analysis of contact stresses due to combined bending and sliding of high performance fibres

Analytical formulas for the estimation of pressure and shear stresses due to friction on bent surfaces during the handling of fibers in the manufacture of industrial textiles and composites have been derived using the drive belt formula and Hertz contact stress relations. Experimentally measured at low speed, the forces and coefficients of friction give shear stresses in the same range as for the

A novel blood group B subgroup: serological and genetic studies

A discrepancy in the ABO blood groups between a newborn child and her parents was identified. Serological and DNA investigative techniques were performed. A weak variant of B (B-w) was detected on the erythrocytes of the child, her grandmother and great-uncle. Adsorption-elution studies showed that their erythrocytes adsorb and yield anti-B on elution. The B-w antigenic strength of the A(1)B(w) ce

Acute rotational trauma to the knee: poor agreement between clinical assessment and magnetic resonance imaging findings.

To determine the incidence of anterior cruciate ligament (ACL) injuries in the general population; the pathology associated with a knee sprain verified by magnetic resonance imaging (MRI); and the agreement between clinical findings and MRI.Materials and methods: Inclusion criterion was an acute rotational trauma to the knee associated with effusion. One hundred and fifty-nine consecutive patients

A Detailed Modeling Study for Primary Reference Fuels and Fuel Mixtures and Their Use in Engineering Applications

The aim of this work is to generate detailed and simplified kinetic models for the oxidation of the Primary Reference Fuels (PRF) n-heptane, iso-octane and their mixtures, with low numbers of species and reactions. These mechanisms are consistent in terms of the choice of kinetic parameters for the different reaction classes. The further aim is to validate the kinetic models for a wide range of di

Bladder cancer, a two phased disease?

The processes of intraepithelial migration, intraluminal seeding, and field cancerization as models for initiation, spread, and recurrences of urothelial cell carcinoma (UCC) are reviewed in light of recent molecular investigations. The accumulated molecular data on synchronous and metachronous tumors indicate that the majority of recurrent and multiple tumors are monoclonal. Molecular data has al

Wideband diversity in multipath channels with nonuniform power dispersion profiles

The focus of this paper is to derive the symbol error probability (SEP) of a Rake receiver with a limited number of fingers that track the strongest multipath components in a frequency-selective Rayleigh fading channel. We develop an analytical framework that allows the computation of the SEP for nonuniform power dispersion profiles (PDPs) and spreading bandwidth. By transforming the physical Rake

Smoking particles enhance endothelin A and endothelin B receptor-mediated contractions by enhancing translation in rat bronchi.

Background Smoking is known to cause chronic inflammatory changes in the bronchi and to contribute to airway hyper-reactivity, such as in bronchial asthma. To study the effect of smoking on the endothelin system in rat airways, bronchial segments were exposed to DMSO-soluble smoking particles (DSP) from cigarette smoke, to nicotine and to DMSO, respectively. Methods Isolated rat bronchial segment

Bose-Einstein correlations in the Lund model

By providing the Lund Model fragmentation process with a quantum-mechanical framework we extend the results of previous work to situations where there are very many identical bosons. We investigate the features of the weight distributions in some detail and in particular exhibit three-particle BE-correlations, the influence on the rho-spectrum and the difference between charged and neutral pion co

State of protochlorophyll and chlorophyll in corn roots

The protochlorophyll(ide) present in primary roots of dark-grown corn (Zea mays) seedlings has an in vivo absorption maximum at 634 nm. Red light converts the pigment to chlorophyll(ide) a with an absorption maximum at 675 nm.

The influence of multiple introduced predators on a littoral pond community

In a replicated field experiment we studied the effects of natural densities of two exotic consumers, the predatory and herbivorous signal crayfish (Pacifastacus leniusculus) and the predatory rainbow trout (Oncorhynchus mykiss), on multiple trophic levels of a pond community. The goals were to: (1) determine the individual and combined effects of predators on macroinvertebrates, macrophytes, and

5-(2 '-oxoheptadecyl)-resorcinol and 5-(2 '-oxononadecyl)-resorcinol, cytotoxic metabolites from a wood-inhabiting basidiomycete

5-(2'-oxoheptadecyl)-resorcinol (1) and 5-(2'-oxononadecyl)-resorcinol (2) were isolated from fermentations of an imperfect basidiomycete. The structures of the compounds were determined by spectroscopic techniques. Both compounds exhibit cytotoxic effects against the human colon tumor cell lines COLO-320, DLD-1 and HT-29 and the human promyeloid leukemia cell line HL-60, the human leukemia T cell

Supersensitivity in rat micro-arteries after short-term denervation

Contractile responses to phenylephrine and high-K+ were investigated in vitro in microvascular preparations from the rat medial plantar artery, a branch from the saphenous artery, obtained after short-term denervation in vivo. Two groups of animals were studied: (1) animals undergoing surgical resection of the saphenous nerve, and (2) animals undergoing surgical resection of both the sciatic and s

Impairment of bone turnover in elderly women with hip fracture

Hip fracture is one of the most severe consequences of osteoporosis affecting aged women. However, abnormalities of bone turnover responsible for bone loss in this condition have not been clearly defined. To further evaluate the bone metabolic status of women sustaining hip fracture, we have prospectively measured serum osteocalcin as a marker of bone formation and urinary excretion of pyridinolin

Failure of transdifferentiation of adult hematopoietic stem cells into neurons.

Previous studies of bone marrow-derived stem cell transdifferentiation into neurons have not involved purified cell populations and determined their exact phenotype prior to differentiation. The present study investigates whether highly purified mouse adult hematopoietic stem cells (HSCs), characterized by lineage marker depletion and expression of the cell surface markers Sca1 and c-Kit (Lin(-)Sc

Quality of life in the elderly population: an example exploring interrelationships among subjective well-being, ADL dependence, and housing accessibility.

During recent decades, research on quality of life has gained increasing interest. In gerontology, the assessment of objective as well as subjective dimensions is recommendable, and the most innovative research will involve the study of the interrelationships of several components. In empirical research objective environmental factors have rarely been explored. The aim of this study was to explore