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Skin of the Cretaceous mosasaur Plotosaurus: implications for aquatic adaptations in giant marine reptiles.

The physical nature of water and the environment it presents to an organism have long been recognized as important constraints on aquatic adaptation and evolution. Little is known about the dermal cover of mosasauroids (a group of secondarily aquatic reptiles that occupied a wide array of predatory niches in the Cretaceous marine ecosystems 92-65 Myr ago), a lack of information that has hindered i

A new mass conservation approach to the study of CO2 advection in an alpine forest

A new method is proposed for the computation of CO2 Net Ecosystem Exchange (NEE) and its components in a forest ecosystem. Advective flux is estimated by taking into account the air mass conservation principle. For this purpose, wind and dry air density values on the surface of the control volume are first corrected and then the advective flux is estimated on the surface of the control volume. Tur

Recombinant human albumin as protein source in culture media used for IVF: a prospective randomized study

Oocytes obtained from 85 women undergoing IVF/intracytoplasmic sperm injection (ICSI) treatment were randomly selected for culture in media containing either human serum albumin (HSA), (n = 42) or recombinant human albumin (rHA), (n = 43). At the time of transfer, the two embryos with the overall best morphology were selected on day 2, 3 or 5. Comparable rates of fertilization, cleavage, blastocys

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.

Metastable levels in Sc II: lifetime measurements and calculations

The lifetime of the metastable level 3d(21)G(4) in a singly charged scandium has been experimentally investigated at the ion storage ring CRYRING. A laser probing technique has been used for the studies. We also report calculated lifetimes and transition rates for 10 metastable levels in Sc II, including the 3d(21)G(4) state, by calculations using configuration interaction wave functions. The life

Quantitative analysis of the generation of different striatal neuronal subtypes in the adult brain following excitotoxic injury.

Recent findings in adult rodents have provided evidence for the formation of new striatal neurons from subventricular zone (SVZ) precursors following stroke. Little is known about which factors determine the magnitude of striatal neurogenesis in the damaged brain. Here we studied striatal neurogenesis following an excitotoxic lesion to the adult rat striatum induced by intrastriatal quinolinic aci

Long-term cognitive functional limitations post stroke: objective assessment compared with self-evaluations and spouse reports.

This study was part of a Swedish interdisciplinary research project targeting accessibility problems in public transport for people with cognitive functional limitations (CFLs). The objective was to describe and compare different assessment perspectives of long-term CFLs among community citizens having had CFLs in the acute stroke phase but with moderate physical limitations. Eighty-four participa

Cryo-fracture TEM: direct imaging of a random mesh phase.

A novel and a simple method that allows direct imaging of viscous samples by cryo-TEM (cryo-transmission electron microscopy) is presented. A fracture on the vitrified sample is created in a controlled way. In the fracture, some edges are thin enough to allow direct imaging in transmission mode. The method was used to directly image a nonionic surfactant lamellar phase where a random mesh structur

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