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2-Butyne on Si(001) at room temperature: An XPS and NEXAFS study

We present here a study of the adsorption of 2-butyne (CH3-C equivalent to C-CH3) on the Si(0 01)-2 x 1 silicon surface at room temperature using synchrotron radiation photoemission spectroscopy (XPS) and X-ray absorption spectroscopy (NEXAFS). In particular, the Si2p and C1s core levels were followed by real-time photoemission (measuring while dosing). The intensity of the Si2p surface state comp

Genetic Effects on Old-Age Cognitive Functioning: A Population-Based Study

Associations between genotypes and cognitive outcomes may provide clues as to which mechanisms cause individual differences in old-age cognitive performance. We investigated the effects of five polymorphisms on cognitive functioning in a population-based sample of 2,694 persons without dementia (60-102 years). A structural equation model (SEM) was fit to the cognitive data, yielding five specific

Variation and control of growth-form in the moss Hylocomium splendens

The moss Hylocomium splendens has both sympodial and monopodial forms of growth. One aim of this study was to document the growth-form of shoots from different populations. A further aim was to discover the extent to which genetic or environmental factors determine whether monopodial or sympodial growth-form is predominant in a population. Switching between growth-forms within shoots occurs in mos

The influence of neuropeptide Y and norepinephrine on ovulation in the rat ovary

Neuropeptide Y (NPY) was measured in tissue extracts from ovaries of rats treated with pregnant mare serum gonadotropin (PMSG). The extracted NPY-immunoreactive material was identical to synthetic human NPY with regard to size and hydrophobicity as evaluated by gel filtration and high performance liquid chromatography. The concentration of NPY was related to the estrous cycle and a maximum was obs

Gas diffusion electrodes and membrane electrode assemblies based on a sulfonated polysulfone for high-temperature PEMFC

Membrane electrode assemblies (MEAs) with a sulfonated polysulfone (sPSU) as the proton-conducting phase were fuel cell evaluated at varying temperatures in over-humidified conditions. The sPSU was prepared by a direct polycondensation involving a commercially available sulfonated naphthalene diol monomer. The gas diffusion electrodes (GDEs) and MEAs were successfully fabricated and a thorough mor

A syndrome of joint laxity and impaired tendon integrity in lumican- and fibromodulin-deficient mice

Lumican and fibromodulin regulate the assembly of collagens into higher order fibrils in connective tissues. Here, we show that mice deficient in both of these proteoglycans manifest several clinical features of Ehlers-Danlos syndrome. The Lum(-/-)Fmod(-/-) mice are smaller than their wild type littermates and display gait abnormality, joint laxity, and age-dependent osteoarthritis. Misaligned kne

Further reflections on the performative experiences of artefacts for everyday use

The article may be seen as a sequel to my paper delivered at a conference on art historical subjectivity and methodology in Stockholm 1999, initiated by Margaretha Rossholm Lagerlöf. – Now I will try to move that analysis a little step further by discussing some problems concerning the more explicit performative effects and experiences of everyday technical objects and their occasionally strange v

An improved capillary model for describing the microstructure characteristics, fluid hydrodynamics and breakthrough performance of proteins in cryogel beds.

A capillary-based model modified for characterization of monolithic cryogels is presented with key parameters like the pore size distribution, the tortuosity and the skeleton thickness employed for describing the porous structure characteristics of a cryogel matrix. Laminar flow, liquid dispersion and mass transfer in each capillary are considered and the model is solved numerically by the finite

Equalising sensor energy and maximizing sensor network lifespan using RETT

Lately, sensor networks have received much attention in the research community. One of the aims of these networks is to make them self-configuring and self-healing so that they can be easily deployed and self-sufficient. A fundamental limitation with sensor networks is their limited life span because of their battery operation. To that end, much research has been carried out to maximize the life s

New improved tests for cointegration with structural breaks

This article proposes Lagrange multiplier-based tests for the null hypothesis of no cointegration. The tests are general enough to allow for heteroskedastic and serially correlated errors, deterministic trends, and a structural break of unknown timing in both the intercept and slope. The limiting distributions of the test statistics are derived, and are found to be invariant not only with respect

Decreased levels of soluble receptor for advanced glycation end products in patients with rheumatoid arthritis indicating deficient inflammatory control

The receptor for advanced glycation end products ( RAGE) is a member of the immunoglobulin superfamily being expressed as a cell surface molecule and binding a variety of ligands. One of these ligands is high-mobility group box chromosomal protein 1, a potent proinflammatory cytokine, expression of which is increased in synovial tissue and in synovial fluid of rheumatoid arthritis (RA) patients. T

Anatomy of the inferior interatrial route in humans

Aims To explore the morphology of the proximal coronary sinus (CS) and the surrounding tissues in order to identify possible routes for interatrial conduction. Method Specimens containing interatrial septum and proximal CS were taken from 21 necropsied hearts and sliced into 10-mu m thick parallel histological sections in 1-mm steps starting from the valve plane, up to the atrial. roof (40-80 sect

The natural history of small duct primary sclerosing cholangitis

Background & Aims: The long-term prognosis of patients with small-duct primary sclerosing cholangitis (PSC) remains incompletely characterized. We aimed at determining the natural history and long-term outcomes of a large number of patients with small-duct PSC. Methods: Data from 83 patients with well-characterized small-duct PSC from several medical institutions in Europe and the United State

Full counting statistics of multiple Andreev reflections in incoherent diffusive superconducting junctions

We present a theory for the full distribution of current fluctuations in incoherent diffusive superconducting junctions, subjected to a voltage bias. This theory of full counting statistics of incoherent multiple Andreev reflections is valid for an arbitrary applied voltage. We present a detailed discussion of the properties of the first four cumulants as well as the low and high voltage regimes o

Designing simultaneous saccharification and fermentation for improved xylose conversion by a recombinant strain of Saccharomyces cerevisiae.

Wheat straw is an abundant agricultural residue which can be used as a raw material for bioethanol production. Due to the high xylan content in wheat straw, fermentation of both xylose and glucose is crucial to meet desired overall yields of ethanol. In the present work a recombinant xylose fermenting strain of Saccharomyces cerevisiae, TMB3400, cultivated aerobically on wheat straw hydrolysate, w