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A new constraint for gamma-ray burst progenitor mass

Recent comparative observations of long-duration gamma-ray bursts (LGRBs) and core collapse supernova (cc SN) host galaxies demonstrate that these two, highly energetic transient events are distributed very differently upon their hosts. LGRBs are much more concentrated on their host galaxy light than cc SN. Here we explore the suggestion that this differing distribution reflects different progenit

Fiber optic system for in vivo real-time determination of tissue optical properties from steady-state diffuse reflectance measurements

We present a versatile and compact fiber optic probe for real-time determination of the absorption and the reduced scattering coefficients from spatially resolved continuous wave diffuse reflectance measurements. The probe collects the diffuse reflectance at six distances in the range 0.6 - 7.8 mm at four arbitrary wavelengths, which were 660, 785, 805, and 974 nm in these experiments. The maximum

Decreased levels of intrathecal interleukin 1 receptor antagonist in Alzheimer's disease

A growing body of evidence points out the potential role of inflammatory mechanisms in the pathophysiology of brain damage in dementia. In previous studies, we have demonstrated intrathecal production of the proinflammatory cytokine tumor necrosis factor (TNF)alpha in patients with Alzheimer's disease (AD). The aim of the present study was to investigate the downstream products of TNF-alpha expres

Path generation issues for survivable network design

Link dimensioning and routing problems in resilient network design are considered. Reliable network operation is ensured by means of flow restoration which is performed on preselected protection (backup) paths that can absorb traffic overflows from failed primary paths. Backup and primary flows use separated link capacities, and can be split among many paths. In the paper, two restoration models a

The Demand-control-support model and health among women and men in similar occupations

The aim of the study was to investigate the main and the interaction effects of the demand-control-support (DCS) model on women’s and men’s health in a Swedish telecom company. According to the DCS model, work that is characterized by high demands, low decision latitude, and low support decreases health and well-being. Furthermore, control and support are assumed to interact in protecting against

Assessment of radical scavenging capacity of Agrimonia extracts isolated by supercritical carbon dioxide

The results on the extraction of natural compounds from Agrimonia eupatoria and Agrimonia procera by using supercritical carbon dioxide (SC-CO2) are presented. Two agrimony species were extracted in laboratory scale equipment at various parameters and it was found that in case of A. eupatoria the increase in extraction pressure and the addition of a co-solvent ethanol remarkably increases the yiel

Formation of new chromosomes as a virulence mechanism in yeast Candida glabrata.

In eukaryotes, the number and rough organization of chromosomes is well preserved within isolates of the same species. Novel chromosomes and loss of chromosomes are infrequent and usually associated with pathological events. Here, we analyzed 40 pathogenic isolates of a haploid and asexual yeast, Candida glabrata, for their genome structure and stability. This organism has recently become the seco

Physics with Ge-Miniball Arrays

For the measurement of rare gamma decays with low gamma-ray multiplicities (M-gamma < 15) dedicated Ge-detector arrays are being developed. They are optimized with respect to the full-energy peak efficiency rather than the resolving power. These so-called miniball arrays will pre dominantly be used at radioactive ion beam facilities. The detector arrays will have a high granularity using segmented

Inter-ocular interference and circadian regulation of the chick electroretinogram

Illumination of a chick’s eye allows light to pass through to the retina of the contralateral eye. Electroretinographic (ERG) recording employing the scalp or comb as a reference results in shorter implicit time, higher amplitude and lower sensitivity during the day than during the night in a light:dark (LD) cycle and in constant darkness (DD). ERG recordings employing the contralateral eye as ref

Neuroendocrine cells and nerves in the prostate of the guinea pig: effects of peripheral denervation and castration

BACKGROUND: Neuroendocrine (NE) cells and nerves in the prostate gland are thought to play a central role in the regulation of growth, cellular differentiation and homeostasis of secretory activity. The objective of this experimental study was to describe the effects of peripheral denervation and castration on NE cells and nerves in the guinea pig prostate. METHODS: Guinea pigs underwent sham-oper

A novel cell force sensor for quantification of traction during cell spreading and contact guidance

In this work, we present a ridged, microfabricated, force sensor that can be used to investigate mechanical interactions between cells exhibiting contact guidance and the underlying cell culture substrate, and a proof-of-function evaluation of the force sensor performance. The substrates contain arrays of vertical pillars between solid ridges that were microfabricated in silicon wafers using photo

alpha(1)-Antitrypsin, old dog, new tricks - alpha 1-Antitrypsin exerts in vitro anti-inflammatory activity in human monocytes by elevatin cAMP

Regulation of serine protease activity is considered to be the sole mechanism for the function of alpha(1)-antitrypsin (AAT). However, recent reports of the anti-inflammatory effects of AAT are hard to reconcile with this classical mechanism. We discovered that two key activities of AAT in vitro, namely inhibition of endotoxin-stimulated tumor necrosis factor-a and enhancement of interleukin-10 in

Multidose pharmacokinetics of factor IX: implications for dosing in prophylaxis

The aim of this study was to investigate the use of single-dose pharmacokinetic data for factor IX (FIX) to predict multidose pharmacokinetics and explore their use for pharmacokinetic dosing in prophylactic treatment of haemophilia B. Eight patients with severe haemophilia B were enrolled. Using single-dose pharmacokinetic data for each patient, plasma factor IX procoagulant activity (FIX:C) curv

Rheological behavior of amylopectin and beta-lactoglobulin phase-segregated aqueous system

The rheological behavior of amylopectin-beta-lactoglobulin-water system in the region of incompatibility was studied by performing constant shear rate and oscillatory measurements. Phase-segregated samples were prepared at concentrations that laid over the binodal and tie-lines. The results were interpreted in terms of the isostress and isostrain blending laws. For this purpose the bases of Takaya

Monitor – Biology

The hottest developments in the fields of cancer research, neuroscience, genomics and proteomics, anti-virals and more, with a pick of the key research papers in these areas.

Compaction of DNA by gemini surfactants: Effects of surfactant architecture

The interaction between bacteriophage T4 DNA and cationic gemini surfactants was studied by the use of fluorescence microscopy. Upon addition of surfactant, DNA undergoes a transition from random coil to globule, with an intermediate coexistence region. The state behavior of a DNA-gemini surfactant system was found to depend on spacer length, valency, head group size, and tail length. A series of

Modeling diesel spray ignition using detailed chemistry with a progress variable approach

In this work, a progress variable approach is used to model diesel spray ignition with detailed chemistry. The flow field and the detailed chemistry are coupled using the flamelet assumption. A flamelet progress variable is transported by the computational fluid dynamics (CFD) code. The progress variable source term is obtained from an unsteady flamelet library that is evaluated in each grid cell.