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Imaging atomic structure in metal nanoparticles using high-resolution cryo-TEM

It has been shown, by imaging gold (200) planes, that it is possible to achieve better than 0.20-nm structural resolution in cryo-transmission electron microscopy (cryo-TEM). This has been done using commercially available cryo equipment and using a 300-kV field emission gun (FEG) TEM. The images of 15-nm gold particles embedded in amorphous frozen water clearly show the (111) planes (separated by

Effects of nitrous oxide on human regional cerebral blood flow and isolated pial arteries

BACKGROUND: Results from previous studies on the effect of nitrous oxide (N2O) on the cerebral circulation are conflicting. Early reports claim N2O to have no effect whereas recent findings demonstrate a cerebral cortical vasodilatation during N2O inhalation, but the regional cerebral blood flow (CBF) in the subcortical structures is unknown. METHODS: Regional CBF was measured three-dimensionally

Excited-state charge transfer dynamics in systems of aromatic adsorbates on TiO2 studied with resonant core techniques

Resonant core spectroscopies are applied to a study of the excited electron transfer dynamics on a low-femtosecond time scale in systems of aromatic molecules (isonicotinic acid and bi-isonicotinic acid) adsorbed on a rutile TiO2(110) semiconductor surface. Depending on which adsorbate state is excited, the electron is either localized on the adsorbate in an excitonic effect, or delocalizes rapidl

Parameters of the diffusion leaky integrate-and-fire neuronal model for a slowly fluctuating signal

Stochastic leaky integrate-and-fire (LIF) neuronal models are common theoretical tools for studying properties of real neuronal systems. Experimental data of frequently sampled membrane potential measurements between spikes show that the assumption of constant parameter values is not realistic and that some (random) fluctuations are occurring. In this article, we extend the stochastic LIF model, a

Quantitative adsorption and local structures of Gallium(III) at the water-alpha-FeOOH interface

The adsorption of Ga(III) at the water-alpha-FeOOH (goethite) interface has been investigated by means of quantitative adsorption experiments, extended X-ray absorption fine structure (EXAFS) spectroscopy, and surface complexation modeling. Under the conditions studied, pH range 3-11 and surface coverages of 0.9-3.2 mu mol/m(2), Ga(III) was found to adsorb strongly to alpha-FeOOH, and the surface

Streptococcal beta protein has separate binding sites for human factor H and IgA-Fc.

The group B streptococcus (GBS) is the most important cause of life-threatening bacterial infections in newborn infants. Protective immunity to GBS infection is elicited by several surface proteins, one of which, the beta protein, is known to bind human IgA-Fc. Here, we show that the beta protein also binds human factor H (FH), a negative regulator of complement activation. Absorption experiments

Tor: A case study of a boy between the ages of three and eight

Longitudinal data are presented on a boy between the ages ofthree and eight. At age three he received a diagnosis oflanguage impairment and at age six a diagnosis of high-functioning autism. Results are presented from extensive assessments at four points in time, including interviews with his mother and teachers. The results indicate that the boy s core problem was poor language comprehension, esp

Lithium Coordination and Mobility in Gel Electrolytes Based on an Acrylate Polymer with Ethylene Oxide Side Chains.

Multinuclear NMR has been used to investigate the structure and mobility of a series of polymer gel electrolytes. The co-polymers used as matrixes in the gels have acrylate backbones and side chains of ethylene oxide, where the length of the side chains has been varied, while the ratio of acrylate to ethylene oxide has been kept constant. The electrolyte is a mixture of lithium perchlorate and two

Endometrial expression of vasopressin, oxytocin and their receptors in patients with primary dysmenorrhoea and healthy volunteers at ovulation.

OBJECTIVE: To investigate gene expressions for neurohypophyseal and ovarian hormones as well as their receptors in the endometrium of women with primary dysmenorrhoea and healthy subjects at ovulation. STUDY DESIGN: A group of eight women with moderate to severe dysmenorrhoea and eight healthy subjects were compared in parallel between 18 and 35 years of age, regularly menstruating, non-overweight

High-resolution Late Silurian correlations between Gotland, Sweden and the Broken River region, NE Australia: Lithologies, conodonts and isotopes

High-resolution correlations, partly with a precision better than 10 ka, are achieved between late Ludfordian sequences on Gotland, Sweden (on Baltica), and a section (COG) through the Coral Gardens Formation along the Broken River, northeastern Australia (on Gondwana), despite these sections having been on different palaeocontinents facing different oceans. The interval is characterised by rapid,

13C NMR isotopomer analysis reveals a connection between pyruvate cycling and glucose-stimulated insulin secretion (GSIS)

Cellular metabolism of glucose is required for stimulation of insulin secretion from pancreatic beta cells, but the precise metabolic coupling factors involved in this process are not known. In an effort to better understand mechanisms of fuel-mediated insulin secretion, we have adapted 13C NMR and isotopomer methods to measure influx of metabolic fuels into the tricarboxylic acid (TCA) cycle in i

Biogas as a resource-efficient vehicle fuel

There are currently strong incentives for increased use of renewable fuels in the transport sector worldwide. However, some bioethanol and biodiesel production routes have limitations with regard to resource efficiency and reduction of greenhouse gases. More efficient biofuel systems are those based on lignocelluloses and novel conversion technologies. A complementary strategy to these is to incre

Eye evolution: the blurry beginning.

Recent work on the expression of retinal transcription factors and other molecular cues delivers interesting but partly contradictory information on the early phases of eye evolution.

Nigrostriatal {alpha}-synucleinopathy induced by viral vector-mediated overexpression of human {alpha}-synuclein: A new primate model of Parkinson's disease.

We used a high-titer recombinant adeno-associated virus (rAAV) vector to express WT or mutant human alpha -synuclein in the substantia nigra of adult marmosets. The alpha -synuclein protein was expressed in 90-95% of all nigral dopamine neurons and distributed by anterograde transport throughout their axonal and dendritic projections. The transduced neurons developed severe neuronal pathology, inc

On two numerical methods for homogenization of Maxwell's equations

When the wavelength is much larger than the typical scale of the microstructure in a material, it is possible to define effective or homogenized material coefficients. The classical way of determination of the homogenized coefficients consists of solving an elliptic problem in a unit cell. This method and the Floquet-Bloch method, where an eigenvalue problem is solved, are numerically compared wit

Low-Complexity Binary Morphology Architectures with Flat Rectangular Structure Elements

This article describes and evaluates algorithms and their hardware architectures for binary morphological erosion and dilation. In particular, a fast stall-free low-complexity architecture is proposed that takes advantage of the morphological duality principle and structuring element (SE) decomposition. The design is intended to be used as a hardware accelerator in real-time embedded processing ap

Two-dimensional oxide on Pd(111).

The oxidation of Pd(111) leads to an incommensurate surface oxide, which was studied by the use of scanning tunneling microscopy, surface x-ray diffraction, high resolution core level spectroscopy, and density functional calculations. A combination of these methods reveals a two-dimensional structure having no resemblance to bulk oxides of Pd. Our study also demonstrates how the atomic arrangement

Long-term outcome of meniscectomy: symptoms, function, and performance tests in patients with or without radiographic osteoarthritis compared to matched controls

OBJECTIVE: To describe the long-term influence of meniscectomy on pain, functional limitations, and muscular performance. To assess the effects of radiographic osteoarthritis (OA), gender and age on these outcomes in patients with meniscectomy. DESIGN: 159 subjects (35 women), mean age 53 years, were examined 19 (17-22) years after open meniscectomy. Self-reported symptoms and function were assess