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Development and Application of a ReaxFF Reactive Force Field for Oxidative Dehydrogenation on Vanadium Oxide Catalysts

We have developed a new ReaxFF reactive force field to describe accurately reactions of hydrocarbons with vanadium oxide catalysts. The ReaxFF force field parameters have been fit to a large quantum mechanics (QM) training set containing over 700 structures and energetics related to bond dissociations, angle and dihedral distortions, and reactions between hydrocarbons and vanadium oxide clusters.

Effects of atmospheric dispersion on the PSF background level

Atmospheric dispersion represents a relatively overlooked problem in connection with the ultimate quality of ELT images corrected by adaptive optics (AO). The aim of this paper is to evaluate the contribution from atmospheric dispersion to the background level of the point-spread function (PSF). Since proper suppression of this level is important for the prospects for direct exo-planet observation

Associations between CB-153 and p,p'-DDE and hormone levels in serum in middle-aged and elderly men.

Background: Animal and epidemiologic data indicate that exposure to persistent organochlorine pollutants (POPs) may disrupt the hypothalamus-pituitary-thyroid (HPT) and the hypothalamus-pituitary-gonadal (HPG) axes. We have assessed whether the POP-biomarkers 2,2'4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethene (p,p'-DDE) affect thyrotropin (TSH), thyroid hormo

CART in the enteric nervous system.

The expression, distribution, origin, projections, chemical coding and functions of cocaine and amphetamine-regulated transcript (CART) in the gastro-intestinal tract are reviewed. CART is extensively expressed in the enteric nervous system. Except from being a possible modulator of NO induced intestinal relaxation CART does not seem to play any pivotal role in intestinal motility. Accumulating ev

Encouraging outlook for recovery of a once severely exploited marine megaherbivore

Aim To critically review the status of the green sea turtle (Chelonia mydas) using the best available scientific studies as there is a prevailing view that this species is globally endangered and its marine ecosystem functions compromised. Location Ogasawara (Japan), Hawaii (USA), Great Barrier Reef (Australia), Florida (USA), Tortuguero (Costa Rica). Methods We compiled seasonal nesting activity

Effect of mutant alpha-synuclein on dopamine homeostasis in a new human mesencephalic cell line.

Mutations in alpha-synuclein have been linked to rare, autosomal dominant forms of Parkinsons disease. Despite its ubiquitous expression, mutant alpha-synuclein primarily leads to the loss of dopamine-producing neurons in the substantia nigra. Alpha-synuclein is a presynaptic nerve terminal protein of unknown function, though some studies suggest it is important for synapse formation and maintenan

Octreotide scintigraphy and Chromogranin A do not predict clinical response in patients with octreotide acetate-treated hormone-refractory prostate cancer

In this pilot study, the predictive value of Octreotide scintigraphy (Octreoscan) and/or Chromogranin-A (CgA) was investigated in patients with hormone-refractory prostate cancer treated with Octreotide acetate. In total, 20 patients with progressive disease and bone metastases entered the trial. At baseline Octreoscan, CgA, PSA, alkaline phosphates (ALP) and two self-administered questionnaires (

Changes in the carbon cycle during the last deglaciation as indicated by the comparison of Be-10 and C-14 records

The variations in atmospheric radiocarbon (C-14) concentration during the last 50 000 years can be attributed to changes in the C-14 production rate (due to changes in solar activity, the geomagnetic field and/or interstellar galactic cosmic ray flux) and to changes in the global carbon cycle. The relative contributions of these processes is the subject of current debate. Although the discrepancie

Decolorization of the textile dyes Reactive Red 2 and Reactive Blue 4 using Bjerkandera sp Strain BOL 13 in a continuous rotating biological contactor reactor

The decolorization of two different textile dyes, Reactive Red 2 and Reactive Blue 4, was studied in batch as well as continuous experiments using Bjerkandera sp. Strain BOL 13. The batch experiments were performed to study the decolorization of the dyes separately as well as in a mixture. The results from the experiments showed that the fungus decolorized both dyes. The absorbance was measured at

In-situ SEM study of fatigue crack growth behaviour in IN718

Fatigue crack growth experiments on Inconel 718 have been performed in a scanning electron microscope at room temperature. The investigated cracks were approximately 1-3 mm long and the samples used were thin 10 mm wide plates. The crack opening stress was found to vary significantly, even in the Paris region, for a constant stress ratio. Crack growth was predominantly found to be either growth on

A multidimensional multispecies continuum model for heterogeneous biofilm development

We propose a multidimensional continuum model for heterogeneous growth of biofilm systems with multiple species and multiple substrates. The new model provides a deterministic framework for the study of the interactions between several species and their effects on biofilm heterogeneity. It consists of a system of partial differential equations derived on the basis of conservation laws and reaction

Scotopic colour vision in nocturnal hawkmoths

Humans are colour-blind at night, and it has been assumed that this is true of all animals. But colour vision is as useful for discriminating objects1 at night as it is during the day. Here we show, through behavioural experiments, that the nocturnal hawkmoth Deilephila elpenor uses colour vision to discriminate coloured stimuli at intensities corresponding to dim starlight (0.0001 cd m-2). It can

The experience of Middle Eastern men living in Sweden of maternal and child health care and fatherhood: focus-group discussions and content analysis.

Objective To describe how men from the Middle East experience Swedish maternity and child health care. An integral part of the aim of this study has also been to describe the experiences of men from the Middle East when becoming and being a father in Sweden. Design, setting and participants an exploratory, qualitative study using focus-group discussions and individual interviews, with a semi-st

Systemic lupus international collaborating clinics renal activity/response exercise - Development of a renal activity score and renal response index

Objective. To develop a measure of renal activity in systemic lupus erythematosus and use it to develop a renal response index. Methods. Abstracted data from the medical records of 215 patients with lupus nephritis were sent to 8 nephrologists and 29 rheumatologists for rating. Seven nephrologists and 22 rheumatologists completed the ratings. Each physician rated each patient visit with respect to

On the wings of physics

Some of Maurice Jacob's contributions to the European physics community are described, by giving examples of his great achievements. I have come to the conclusion that his success depended on his far-reaching vision, his ability to define the goals and to find realistic solutions for realizing them. He was a trustworthy partner in negotiations due to his outstanding breath of knowledge, his high s

Breast cancer incidence in ex-smokers in relation to body mass index, weight gain and blood lipid levels

According to several studies breast cancer is more common among former smokers. This study explores whether this association has any relationship with anthropometric measurements or blood lipid levels. The 2082 ex-smokers (mean age 49.9 years) in the Malmo Preventive Cohort were followed for an average of 13.3 years using official cancer registries. This yielded 93 incident breast cancer cases. Oe