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A new understanding of au-assisted growth of III-V semiconductor nanowires

Semiconductor nanowires of III-V materials have generated much interest in recent years. However, the growth mechanisms by which these structures form are not well understood. The so-called vapor-liquid-solid (VLS) mechanism has often been proposed for III-V systems, with a chemically inert, liquid metal particle (typically Au) acting as a physical catalyst. We assert here that An is, in fact, not

More pronounced salt dependence and higher reactivity for platination of the hairpin r(CGCGUUGUUCGCG) compared with d(CGCGTTGTTCGCG)

The DNA interference pathways exhibited by cisplatin and related anticancer active metal complexes have been extensively studied. Much less is known to what extent RNA interaction pathways may operate in parallel, and perhaps contribute to both antineoplastic activity and toxicity. The present study was designed with the aim of comparing the reactivity of two model systems comprising RNA and DNA h

Country of birth, instrumental activities of daily living, self-rated health and mortality: a Swedish population-based survey of people aged 55-74.

There is scant knowledge of the effects of country of birth on the health of individuals in the years prior to and after retirement. The aim of this study was to consider country of birth in relation to health status, instrumental activities of daily living (IADL) and all-cause mortality when adjusted for socioeconomic status (SES). Cross-sectional data were collected between 1986 and 1991 on 8959

Genetic Variation in Brain-Derived Neurotrophic Factor Is Associated with Serotonin Transporter but Not Serotonin-1A Receptor Availability in Men

Background: The serotonergic system, including the serotonin transporter (5-HTT), which is the target of many antidepressants, seems to be influenced by brain-derived neurotrophic factor (BDNF). Methods: Positron emission tomography (PET) was used to address, in 25 and 53 healthy volunteers, respectively, the possible association between six polymorphisms in the gene encoding BDNF and the availabi

Economic evaluation of enzymatic hydrolysis of phenol-pretreated wheat straw

Experimental data from the enzymatic hydrolysis of phenol-pretreated Swedish wheat straw have been used to evaluate the cost fractions of capital and utility, enzyme, and raw material. Two different raw material prices and varying enzyme prices have been used. The evaluation is based on an empirical model for the enzymatic hydrolysis and a computer program where utility and equipment, enzyme, and

Time-dependent radiative transfer in magneto-optical traps

We investigate radiation-imprisonment (RI) phenomena in a system of cold atoms trapped in magneto-optical traps (MOTs) when cooling lasers are switched off for a short period. The problem is formulated within the framework of the Streater-Cooper-Sandle equation that belongs to the Markov class and accounts for photon frequency redistribution in multiple scattering processes. On the basis of a semi

Continuous versus intermittent tamoxifen versus intermittent/alternated tamoxifen and medroxyprogesterone acetate as first line endocrine treatment in advanced breast cancer: An EORTC phase III study (10863)

Background: Continuous ligand depletion of endocrine responsive tumours may enhance resistance to therapy. Intermittent treatment with tamoxifen (T) was considered to mimic (incomplete) ligand depletion and reintroduction. Furthermore it was postulated that alternating tamoxifen with a non-cross resistant endocrine modality could (further) postpone hormone resistance. Patients and methods: Postmen

Two-dimensional conformation-dependent electrophoresis (2D-CDE) to separate DNA fragments containing unmatched bulge from complex DNA samples

DNA fragments containing mispaired and modified bases, bulges, lesions and specific sequences have altered conformation. Methods for separating complex samples of DNA fragments based on conformation but independent of length have many applications, including (i) separation of mismatched or unmatched DNA fragments from those perfectly matched; (ii) simultaneous, diagnostic, mismatch scanning of mul

Long-term repeatability of winter basal metabolic rate and mass in a wild passerine

P>Basal metabolic rate (BMR) is an important trait in the study of energy management of an individual, especially in small wintering passerines from the north which have one of the highest energy turnover rates in vertebrates. Laboratory studies have shown the trait to be repeatable and heritable, despite its plastic nature. However there is currently a lack of empirical data from wild passerine p

EGF-stimulated migration in ovarian cancer cells is associated with decreased internalization, increased surface expression, and increased shedding of the urokinase plasminogen activator receptor.

Objectives. The EGFR is expressed in malignant ovarian tumor tissue, and tissue content of EGFR has been directly associated with poor prognosis in patients with ovarian cancer. The uPA system plays a role in pericellular proteolysis, cell migration, invasion, and is over-expressed in ovarian cancer. This study explored the effects of EGF on uPAR expression in the ovarian cancer cell line OVCAR-3.

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Purpose: Lymph node status is one of the most important prognostic factors in muscle-invasive bladder cancer. The extent of lymphadenectomy performed in conjunction with cystectomy and the question as to whether this is a staging or therapeutic intervention are matters of discussion. The aim of this study was to evaluate the sentinel node (SN) concept and to correlate findings with tumour status i

Improving emergency response capability : an approach for strengthening learning from emergency response evaluations

The objectives of this study are to develop and demonstrate an approach to improve emergency response capability by strengthening individual and organisational learning from the evaluations of specific emergency responses. An approach was developed based on theories of individual and organisational learning. It was applied to evaluations of three instances of emergency response in the city of Malm

Truncated galectin-3 inhibits tumor growth and metastasis in orthotopic nude mouse model of human breast cancer

Purpose: The goal of this research was to evaluate a potential therapeutic agent for breast cancer based on galectin-3 that has been implicated in tumorigenicity and metastasis of breast cancer. The hypothesis was that therapy with NH2-terminally truncated form of galectin-3 (galectin-3C) will be efficacious for reduction in tumor growth and for inhibition of metastases. Experimental Design: Recom

Contact-free measurements and numerical analyses of the strain distribution in the joint area of steel-to-timber dowel joints

Two different dowel-type joints of differing size were loaded in tension parallel to the grain. The strain distribution in the joint area was studied using a contact-free measurement system. The results were compared with those of numerical analysis. The measurement system was found to be a valuable complement to traditional measurement techniques and also to numerical analyses performed in parame

Dissociation of water on oxygen-covered Rh{111}

The adsorption of water and coadsorption with oxygen on Rh{111} under ultrahigh vacuum conditions was studied using synchrotron-based photoemission and photoabsorption spectroscopy. Water adsorbs intact on the clean surface at temperatures below 154 K. Irradiation with x-rays, however, induces fast dissociation and the formation of a mixed OH+H2O layer indicating that the partially dissociated lay

Proteomic variation is as large within as between strawberry varieties

in search for a strawberry (Fragaria ananassa) with low allergen content, we determined the proteomic variation within and between different varieties. Proteomics data were generated by DIGE and proteins identified with MALDI-MS/MS. The amount of the strawberry allergen Fra a 1 varied between different strawberry varieties (CV = 39%). The variation was at the same level, or even slightly larger, d

Allozyme diversity and genetic structure of marginal and central populations of Corylus avellana L. (Betulaceae) in Europe

Corylus avellana L. (hazel, Betulaceae) is a long-lived, widespread shrub in Europe, having its northern range margin in Fennoscandia and a postglacial history involving range-expansion from refugial areas in southern Europe. In this study, we tested for a relationship between marginality and low within-population genetic diversity by assessing patterns of variation at 14 putatively neutral allozy

Induces vasodilatation of rat mesenteric artery in vitro mainly by inhibiting receptor-mediated Ca2+-influx and Ca2+-release

The purpose of this study was to investigate the effect of atropine on peripheral vasodilation and the mechanisms involved. The isometric tension of rat mesenteric artery rings was recorded in vitro on a myograph. The results showed that atropine, at concentrations greater than 1 mu M, relaxed the noradrenalin (NA)-precontracted rat mesenteric artery in a concentration-dependent manner. Atropine-i

Morphological plastic responses to water depth and wave exposure in an aquatic plant (Myriophyllum spicatum)

1 We investigated morphological responses of the submerged macrophyte Myriophyllum spicatum L. to water depth and wave exposure when grown in the same substrate at two sites in two eutrophic lakes. Periphyton production was 4-8 times higher at sheltered than at wave-exposed sites and its influence was further investigated in a glasshouse experiment. Morphological responses in both experiments were