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Spin current diode based on an electron waveguide with spin-orbit interaction

We propose a spin current diode which can work even in a small applied bias condition (the linear-response regime). The prototypal device consists of a hornlike electron waveguide with Rashba spin-orbit interaction, which is connected to two leads with different widths. It is demonstrated that when electrons are incident from the narrow lead, the generated spin conductance fluctuates around a cons

Ion-pair hollow-fiber liquid-phase microextraction of the quaternary ammonium surfactant dicocodimethylammonium chloride

A two-phase hollow-fiber (HF) liquid-phase microextraction (LPME) method was developed for determination of a quaternary ammonium compound surfactant, dicocodimethylammonium chloride, in aqueous samples. The porous HF was fixed on a metal rod support and was impregnated with approximately 6.6 mu L of organic extractant, which was immobilized in the HF pores. Surfactant extraction was facilitated b

Dissociative H2O adsorption on the Si (100) 2× 1 and Ge (100) 2× 1 surfaces

Core-level spectroscopy and valence band photoelectron spectroscopy were used to study H2O adsorption on the Si(100) and Ge(100) surfaces. We find that H2O dissociates into H and OH on both surfaces at 300 K. The H and OH are adsorbed in on top positions on the surface. The OH group is tilted with respect to the surface normal on the Si(100) surface. We consider two possible interpretations for th

Intraperitoneal 5-fluorouracil in the management of colorectal liver cancer

Twenty-five patients with colorectal liver metastases had a subcutaneous portal connection with a peritoneal catheter implanted for the intraperitoneal (i.p.) administration of 5-fluorouracil (5-FU). In five patients, the malignant disease rapidly progressed and the implanted catheter system was never used. Among the remaining 20 patients, seven patients had i.p. 5-FU as adjuvant treatment followi

Alkaline sphingomyelinase activity is decreased in human colorectal carcinoma

BACKGROUND: The metabolism of sphingomyelin generates important signals regulating cell proliferation and apoptosis. Previous studies found that the administration of colon carcinoma carcinogen was associated with an accumulation of membrane sphingomyelin, and that dietary sphingomyelin inhibited promotion of experimental colon carcinoma in mice, indicating that the abnormal metabolism of sphingom

Marked upregulation of cholesterol 25-hydroxylase expression by lipopolysaccharide

During screening of genes upregulated by lipopolysaccharide (LPS; endotoxin) treatment of bone marrow-derived mouse macrophages, it was unexpectedly found that cholesterol 25-hydroxylase (Ch25h) was strongly upregulated. Treatment of macrophages with 10 ng/ml of LPS for 2 h resulted in a 35-fold increase in the expression of Ch25h. In contrast, LPS treatment did not increase the expression of Cyp2

Magnetostriction, elastic moduli, and coupling factors of composite Terfenol-D

Recently it was discovered that composites of Terfenol-D alloys with an insulating binder produce very large magnetostrictions. Resistivities of these composites reach high values, making them attractive for high-frequency applications which require small eddy current losses. In this paper the magnetostriction, magnetization, and Young's moduli measurements made under constant magnetic field condi

Superior underwater vision in a human population of sea gypsies

Humans are poorly adapted for underwater vision. In air, the curved corneal surface accounts for two-thirds of the eye's refractive power, and this is lost when air is replaced by water [1]. Despite this, some tribes of sea gypsies in Southeast Asia live off the sea, and the children collect food from the sea floor without the use of visual aids [2]. This is a remarkable feat when one considers th

Modelling of an electric IR heater at transient and steady state conditions Part I: model and validation

A model for an electric infrared (IR) heater has been developed. The model includes non-grey radiative heat transfer between the different parts of the IR heater, as well as conduction in reflector material and convective cooling of surfaces. The geometry is simplified into one dimension. Using IR module voltage, as the only input, the model predicts the temperature of heater components and coolin

Von Willebrand's disease: clinical management

The aim of treatment of von Willebrand's disease (VWD) is to correct the dual defect of haemostasis, i.e. the abnormal platelet adhesion due to reduced and/or dysfunctional von Willebrand factor (VWF) and the abnormal coagulation expressed by low levels of factor VIII (FVIII). Desmopressin (DDAVP) is the treatment of choice for type 1 VWD because it can induce release of normal VWF from cellular c

Deaths rise in good economic times: evidence from the OECD.

This study uses aggregate data for 23 Organization for Economic Cooperation and Development (OECD) countries over the 1960-1997 period to examine the relationship between macroeconomic conditions and deaths. The main finding is that total mortality and deaths from several common causes rise when labor markets strengthen. For instance, controlling for year effects, location fixed-effects (FE), coun

Self-diffusion NMR studies of the host-guest interaction between beta-cyclodextrin and alkyltrimethylammonium bromide surfactants

Diffusion measurements by nuclear magnetic resonance (NMR) spectroscopy were used to investigate the host-guest association between beta-cyclodextrin (CD) and alkyltrimethylammonium bromide surfactants with different chain lengths, ranging from 6 up to 16 carbons. The scope and limitations of the method in the study of formation of inclusion complexes are discussed. The influences of the presence

Excited state properties of the chromophore of the asFP595 chromoprotein: 2D and 3D theoretical analyses

The ground and excited state properties (e.g., the intramolecular charge and energy transfer, and electron-hole coherence) of the chromophore of the asFP595 chromoprotein from Anemonia sulcata in the neutral and anionic forms are theoretically studied with quantum chemistry methods. The ground-state properties of the asFP595 in the neutral and anionic forms, such as the alternations of the bond le

Sex differences in lung vulnerability to tobacco smoking

Studies have indicated that females are more vulnerable to the deleterious effect of tobacco smoking than males. The current study aimed to investigate the associations between tobacco smoking and reported respiratory symptoms, self-rated health, and lung function by sex. In 1995-1997 65,225 subjects aged greater than or equal to 20 yrs (71% of invited) attended for screening within the Nord-Trond

Identification of surface epitopes of human coagulation factor Va that are important for interaction with activated protein C and heparin

Inactivation of factor Va (FVa) by activated protein C (APC) is a key reaction in the down- regulation of thrombin formation. FVa inactivation by APC is correlated with a loss of FXa cofactor activity as a result of three proteolytic cleavages in the FVa heavy chain at Arg(306), Arg(506), and Arg(679). Recently, we have shown that heparin specifically inhibits the APC- mediated cleavage at Arg(506

A latest Llandovery to latest Ludlow high-resolution biostratigraphy based on the Silurian of Gotland - a summary

A succession of 26 conodont zones and 63 successive subzones and conodont faunas have been identified in the exposed latest Landovery to latest Ludlow strata of Gotland, Sweden. All zones, and several of the subzones and faunas, have been identified elsewhere on Baltica as well as on other palaeocontinents, indicating that this zonation serves well as the standard zonation for calcareous successio