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One-dimensional PtO2 at Pt steps: Formation and reaction with CO

Using core-level spectroscopy and density functional theory we show that a one-dimensional (1D) PtO2 oxide structure forms at the steps of the Pt(332) surface after O-2 exposure. The 1D oxide is found to be stable in an oxygen pressure range, where bulk oxides are only metastable, and is therefore argued to be a precursor to the Pt oxidation. As an example of the consequences of such a precursor e

The Quantitative Relationship between Longitudinal and Radial Function in Left, Right and Total Heart Pumping in Humans.

The total heart volume variation (THVV) during systole has been proposed to be caused by radial function of the ventricles, but definitive data for both ventricles have not been presented. Furthermore, the right ventricle (RV) has been suggested to have a greater longitudinal pumping component than the left ventricle (LV). Therefore, we aimed to compare the stroke volume (SV) generated by radial f

Hoxb4-deficient mice undergo normal hematopoietic development but exhibit a mild proliferation defect in hematopoietic stem cells

Enforced expression of Hoxb4 dramatically increases the regeneration of murine hematopoietic stem cells (HSCs) after transplantation and enhances the repopulation ability of human severe combined immunodeficiency (SCID) repopulating cells. Therefore, we asked what physiologic role Hoxb4 has in hematopoiesis. A novel mouse model lacking the entire Hoxb4 gene exhibits significantly reduced cellulari

Apolipoprotein E genotyping in Alzheimer’s disease and frontotemporal dementia

Alzheimer's disease (AD) and frontotemporal dementia (FTD) are characterized by progressive neuronal loss and microvacuolization, although with different distributions of cortical involvement. In contrast to AD there is no amyloid, senile plaques or tangles in FTD. The involvement of chromosome 19 in AD has been associated with apoliprotein E (ApoE) and the epsi4 gene frequency has been related to

Average risks of breast and ovarian cancer associated with BRCA1 or BRCA2 mutations detected in case series unselected for family history: A combined analysis of 22 studies

Germline mutations in BRCA1 and BRCA2 confer high risks of breast and ovarian cancer, but the average magnitude of these risks is uncertain and may depend on the context. Estimates based on multiple-case families may be enriched for mutations of higher risk and/or other familial risk factors, whereas risk estimates from studies based on cases unselected for family history have been imprecise. We p

How to develop strategies for improving musculoskeletal health.

Musculoskelecal conditions are a major cause of morbidity and evidence-based strategies - such as the European Action Towards Better Musculoskeletal Health - have been developed to reduce their incidence and impact on individuals and on society. This issue is based around that report. These strategies are inclusive of all major musculoskeletal conditions with recommendations for prevention and man

Radiative lifetimes of Zn I, II excited states

Radiative lifetimes of excited states of Zn I (3d(10)4sns S-3(1), n = 6-8; 3d(10) 4snd D-3, n = 4-7) and Zn II (3d(10) 4p P-2(1/2.3/2), 4d D-2(3/2,5/2), 3d(10)5S S-2(1/2)) have been measured using a time-resolved laser-induced fluorescence technique. Single- or two-step excitation of atoms and ions produced by laser ablation was employed. The experimental radiative lifetimes have been compared wit

The impact of foreign board membership on firm value

This study examines the effect of foreign (Anglo-American) board membership on corporate performance measured in terms of firm value (Tobin's Q). Using a sample of firms with headquarters in Norway or Sweden the study indicates a significantly higher value for firms that have outsider Anglo-American board member(s), after a variety of firm-specific and corporate governance related factors have bee

Prevalence of hemochromatosis gene (HFE) mutations in Greece

The frequencies of the hereditary hemochromatosis gene (HFE) mutations C282Y and H63D vary between different populations. There are a limited number of reports regarding the frequency of these mutations in populations of southeastern Europe. Two hundred and sixty-four adult individuals of Greek origin were examined for the C282Y and H63D mutations to determine the allele and genotype frequencies.

Long-term assessment of striatal dopamine transporters in parkinsonian patients with intrastriatal embryonic mesencephalic grafts

Purpose: Single-photon emission computed tomography (SPECT) of striatal dopamine transporters (DAT) has been used to demonstrate presynaptic dopaminergic dysfunction and to monitor the progression of Parkinson's disease. In parkinsonian patients who were implanted with embryonic mesencephalic tissue in the striatum, positron emission tomography (PET) has shown an increase in striatal [F-18]dopa up

Nitric oxide gives maximal response after coronary artery bypass surgery

The dose-response to inhalation of nitric oxide (NO) after coronary artery bypass surgery was studied in seven patients with normal preoperative lung function and chest radiograms. During postoperative controlled ventilation with PEEP 5 and 10 cmH2O, the patients inhaled NO in concentrations of 2 to 25 ppm, in random order, for 6 to 10 minutes. Hemodynamic and oximetric data were analyzed before,

Determination of amylose content in different starches using modulated differential scanning calorimetry

A simple calorimetric method for determination of amylose content in starch is reported. Starches were heated in the presence of two common surfactants, viz., sodium dodecyl sulphate (SDS) and cetyltrimethylammonium bromide (CTAB), and the enthalpies of melting of the amylose-surfactant complexes were determined using Modulated Differential Scanning Calorimetry (MDSC). A large number of native sta

Evaluation and characterization of ammoniumpolyphosphate-pentaerythritol-based systems for intumescent coatings

Intumescent coatings are increasingly used as a method of passive fire protection on steel constructions. By forming a carbon network and releasing a blowing agent, the thin intumescent film swells 100-fold at elevated temperatures. The highly insulating foam effectively prevents the load bearing steel from reaching its critical temperature at which it looses its mechanical properties and collapse

The Danish Prostatic Symptom Score (DAN-PSS-1) questionnaire is reliable in stroke patients

Aims: To investigate the test-retest reliability of Danish Prostatic Symptom Score (DAN-PSS-1) questionnaire in a sample of stroke patients. Methods: A prospective study design was used in which the stroke patients were invited to complete a postal self-administrated DAN-PSS-1 questionnaire twice. The questionnaire consists of 12 questions related to lower urinary tract symptoms (LUTS). The partic

Evolution of UV-B regulation and protection in plants

Plants have evolved under the influence of UV-B radiation and have acquired systems for monitoring it and investing appropriate resources for protection against it, i.e., filters, quenchers of radicals and reactive oxygen species, and repair systems. An hypothesis for how plants monitor radiation has been presented.

Reactions of Diacetylene Ligands with Trinuclear Clusters; Cyclization of Diynes with beta-amino moieties on the surface of H2Os3(CO)10

Reactions of [H2Os3(CO)10] with the substituted diynes R-C2-C2-R' (1, R = Ph, R' = CH2NHPh; 2, R = Ph, R' = CH2NHCH2Ph; 3, R = R' = CH2NHPh) afford the clusters [HOs3(CO)10(L)] (L = {-1:2-PhCH2C(H)=C-C(H)=C-NPh} (4), {-1:2-PhCH2C(H)=C-C(H)=C-NCH2Ph} (5), and {-1:1-CH3CC=C-C(H)=C(H)-NPh} (6), which have been characterized by single-crystal X-ray diffraction analyses as well as by various spectrosco