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Metalorganic vapor phase epitaxy-grown GaP/GaAs/GaP and GaAsP/GaAs/GaAsP n-type resonant tunnelling diodes

We have studied GaP/GaAs/GaP and GaAsxP1-x/GaAs/GaAsxP1-x double-barrier resonant tunnelling diodes grown by metalorganic vapor phase epitaxy. We find that GaP tensile strained barriers in GaP/GaAs/GaP diodes may be grown with a barrier thickness below the critical thickness of about 12 monolayers. However, a corrugation of the strained barrier is observed by transmission electron microscopy. This

The origins of modern proteomes

Distributions of phylogenetically related protein domains (fold superfamilies), or FSFs, among the three Superkingdoms (trichotomy) are assessed. Very nearly 900 of the 1200 FSFs of the trichotomy are shared by two or three Superkingdoms. Parsimony analysis of FSF distributions suggests that the FSF complement of the last common ancestor to the trichotomy was more like that of modern eukaryotes th

Interaction between hydrogen peroxide and titanium: a possible role in the biocompatibility of titanium

Hydroxyl radicals formed from hydrogen peroxide during an inflammatory response are potent agents for cellular deterioration. The behaviour of implanted material in terms of its ability to sustain or stop free radical formation may be therefore very important. In vitro studies of titanium which is known to be biocompatible and osseointegrates into human bone were carried out. In our model studies,

Cytochrome P450 3A4 is the major enzyme responsible for the metabolism of laquinimod, a novel immunomodulator

In the present study, the involvement of cytochrome P450 enzyme( s) in the primary metabolism of laquinimod, a new orally active immunomodulator, has been investigated in human liver microsomes. Hydroxylated and dealkylated metabolites were formed. The metabolite formation exhibited single enzyme Michaelis-Menten kinetics with apparent K-M in the range of 0.09 to 1.9 mM and V-max from 22 to 120 pm

Higher education policy, enrollment, and income inequality

Objective. The objective of this article is to examine whether public expenditure on higher education has an effect on income inequality by increasing enrollment. Methods. Combining data from the World Bank Development Indicators with data from the World Income Inequality Database version 2, we study the relation between government education expenditure and enrollment rates, as well as the relatio

A dinoflagellate cyst record of Holocene climate and hydrological changes along the southeastern Swedish Baltic coast

A high-resolution, well-dated dinoflagellate cyst record from a lagoon of the southeastern Swedish Baltic Sea reveals climate and hydrological changes during the Holocene. Marine dinoflagellate cysts occurred initially at about 8600 cal yr BP, indicating the onset of the Littorina transgression in the southeastern Swedish lowland associated with global sea level rise, and thus the opening of the D

Increased blood-brain barrier permeability of morphine in a patient with severe brain lesions as determined by microdialysis

Intracerebral microdialysis was utilised to obtain information regarding how morphine is transported across the blood-brain barrier (BBB). In a patient with a severe brain injury, we measured simultaneously unbound extracellular fluid (ECF) concentrations of morphine in human brain and in subcutaneous fat tissue, which were compared to morphine levels in arterial blood. This report shows an increa

Spatial and Temporal Distribution of Sucrose Synthase in the Radish Hypocotyl in Relation to Thickening Growth

Sucrose synthase (SuSy) is a key enzyme in the development of storage root of radish. Clarification of its spatial and temporal expression during the thickening growth of radish hypocotyl, which later develops into storage root, was carried out immunologically using light microscopy. Sequential harvests at 3, 7, 11 and 13 d after sowing (DAS) were performed on two radish cultivars having different

Parameter estimation for fractional dispersion model for rivers

The fractional dispersion model for natural rivers, extended by including a first order reaction term, contains four parameters. In order to estimate these parameters a fractional Laplace transform-based method is developed in this paper. Based on 76 dye test data measured in natural streams, the new parameter estimation method shows that the fractional dispersion operator parameter F is the contr

Configurations, construals and change: Expressions of DEGREE

This article challenges the widespread view that DEGREE is a grammatical phenomenon characteristic of certain types of word classes and, instead, argues that DEGREE is pervasive in language and may be associated with most meanings. The main aim of the article is to discuss the results of a number of corpus investigations and experiments of DEGREE meanings in general and of the modification of DEGR

Solubilization and location of phenethylalcohol, benzaldehyde, and limonene in lamellar liquid crystal formed with block copolymer and water

Three fragrances, phenethylalcohol, benzaldehyde, and limonene (that differ in their polarity), were solubilized in lamellar liquid Crystal Using the polyethylene oxide-polypropylene oxide-polyethylene oxide, (EO27PO61EO27), P-104 triblock copolymer, and water. The interlayer spacing of the lamellar liquid crystal were established Using small angle X-ray scattering (SAXS). The SAXS data are used t

Integrated assessment of soil chemical status. 1. Integration of existing models and derivation of a regional database for Switzerland

A regional soil acidification model was developed by integration and adaptation of existing models. The regional model consists of the dynamic multi-layer soil chemistry model SAFE, its steady-state version INITSAFE, the atmospheric deposition and nutrient uptake reconstruction model MAKEDEP, and a routine with empirical relations concerning depth-dependent parameters. A scheme for the extraction

Metabolomic and proteomic analysis of a clonal insulin-producing beta-cell line (INS-1 832/13).

Metabolites generated from fuel metabolism in pancreatic beta-cells control exocytosis of insulin, a process which fails in type 2 diabetes. To identify and quantify these metabolites, global and unbiased analysis of cellular metabolism is required. To this end, polar metabolites, extracted from the clonal 832/13 beta-cell line cultured at 2.8 and 16.7 mM glucose for 48 h, were derivatized followe

Dynamics of proton migration and dissociation in core-excited ethyne probed by multiple ion momentum imaging

The study focuses on the rapid geometry change in ethyne, excited near the carbon 1s edge. Core excitation and ionization leads to population of dicationic states in ethyne. We study three competing dissociation pathways associated with deprotonation in the linear ethyne molecule, and two cases of rapid proton migration. We investigate the alignment of the molecule in the excited state, and find s