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Decoherence and current fluctuations in tunneling through coupled quantum dots

The electronic transport through two coupled quantum dots in series can be described either in a fully coherent approach (e.g. density matrix description or nonequilibrium Green's functions) or in a simple sequential tunneling treatment (Pauli master equation with Fermi's Golden rule for coupling between the quantum dots). It turns out that both descriptions provide the same average current for no

Dispersion of atrial repolarization in patients with paroxysmal atrial fibrillation

To study the role of the dispersion of atrial repolarization (DAR) in the genesis of atrial fibrillation (AF), monophasic action potentials (MAP) were recorded simultaneously from a catheter at the high lateral right atrium (HLRA) and a catheter moving around the high, middle and low lateral right atrium (RA) the high, anterior and posterior septal RA and the RA appendage in 15 patients with parox

Redox signalling in chloroplasts and mitochondria: genomic and biochemical evidence for two-component regulatory systems in bioenergetic organelles

Redox chemistry is central to the primary functions of chloroplasts and mitochondria, that is, to energy conversion in photosynthesis and respiration. However, these bioenergetic organelles always contain very small, specialized genetic systems, relics of their bacterial origin. At huge cost, organellar genomes contain, typically, a mere 0.1% of the genetic information in a eukaryotic cell. There

Challenges Associated with Scaling up Artemisinin Combination Therapy in Sub-Saharan Africa A Review Article

Malaria is the leading cause of morbidity and mortality in Sub-Saharan Africa. One key strategic intervention is provision of early diagnosis and prompt effective treatment. A major setback has been the development of drug resistance to commonly used antimalarials. To overcome this, most countries in Sub-Saharan Africa have adopted Artemisinin Combination Therapy (ACT) as a first line treatment fo

A functional polymorphism in the SULT1A1 gene (G638A) is associated with risk of lung cancer in relation to tobacco smoking

Sulfotransferase 1A1, an important member of sulfotransferase superfamily, is involved in the biotransformation of many compounds including tobacco carcinogens. A single nucleotide polymorphism (G638A) in the sulfotransferase 1A1 (SULT1A1) gene causes Arg213His amino acid change and consequently results in significantly reduced enzyme activity and thermostability. We thus hypothesized that the var

Uptake and intracellular transportation of a bacterial surface protein in lymphoid cells.

Some strains of the human pathogen Streptococcus pyogenes express a surface protein called protein H, which is released from the streptococcal surface by a cysteine proteinase produced by the bacteria. Here, we find that soluble protein H binds to the surface of lymphocytes and granulocytes, and that the molecule is taken up by lymphocytes and transported to the perinuclear region. The translocati

The influence of fat stores on magnetic orientation in day-migrating Chaffinch, Fringilla coelebs

Earlier experimental studies have demonstrated the ability of day-migrating birds to perform migration under overcast skies, thereby indicating use of cues other than solar. The orientation behaviour of the chaffinch, a diurnal migrant, was investigated in orientation cage experiments during the autumn migration period. The aim of our experiments was to examine the relationship between different o

Acute leukaemia and malignant lymphoma patients’ experiences of disease, treatment and nursing care during the active treatment phase: an explorative study.

Five acute leukaemia or highly malignant lymphoma patients at a hospital in southern Sweden were interviewed about their daily living problems, their coping strategies and their opinions about the nursing care they received during the active phase of their treatment. In addition the EORTC QLQ-C30, the Global Life Quality and the Sense of Coherence scales were administered. The data were analysed f

Monoamine transporters in human endometrium and decidua.

BACKGROUND Monoamines play important roles in decidualization, implantation, immune modulation and inflammation. Furthermore, monoamines are potent vasoactive mediators that regulate blood flow and capillary permeability. Regulation of the uterine blood flow is important both during menstruation and pregnancy. Adequate monoamine concentrations are essential for a proper implantation and physiologi

A common variant in PNPLA3, which encodes adiponutrin, is associated with liver fat content in humans

It has recently been suggested that the rs738409 G allele in PNPLA3, which encodes adiponutrin, is strongly associated with increased liver fat content in three different ethnic groups. The aims of the present study were as follows: (1) to try to replicate these findings in European individuals with quantitative measures of hepatic fat content; (2) to study whether the polymorphism influences hepa

Transport Processes in Responding Lipid Membranes: A Possible Mechanism for the pH Gradient in the Stratum Corneum

The “acidic mantle” of the skin surface has been related to several essential functions of the skin, although the origin of the acidity is still obscure. In this paper, we investigate how different transport processes can influence the local proton concentration inside a membrane consisting of oriented lipid bilayers. This system is chosen as a simple model of the extracellular lipids in the upper

Characterization of type I procollagen N-proteinase from fetal bovine tendon and skin. Purification of the 500-kilodalton form of the enzyme from bovine tendon

Procollagen N-proteinase (EC 3.4.24.14) is the enzyme that specifically cleaves the NH2-terminal propeptides from type I procollagen. Two forms of N-proteinase with apparent molecular sizes of 300 and 500 kDa were found in partially purified preparations from fetal bovine tendon extracts. The 500-kDa form of enzyme was purified 16,000-fold with a recovery of 8% from the extracts of the tendons by

Covalently Linked Ruthenium(II)-Manganese(II) Complexes: Distance Dependence of Quenching and Electron Transfer

Continuing our development of artificial models for photosystem II in green plants, a series of compounds have been prepared in which a Ru(bpy)32+ photosensitizer is covalently linked to a manganese(II) electron donor. In addition to a trispicolylamine ligand, two other manganese ligands, dipicolylamine and aminodiacetic acid, have been introduced in order to study ligands that are appropriate for

Induction of ID2 expression by hypoxia-inducible factor-1: ARole in dedifferentiation of hypoxic neuroblastoma cells.

ID (inhibitor of differentiation/DNA binding) proteins, frequently deregulated in advanced human malignancies, can participate in multiple fundamental traits of cancer, such as block of differentiation, increased proliferation, tissue invasiveness, and angiogenesis. We have previously demonstrated that hypoxia decreases expression of neuronal marker genes in neuroblastoma, but induces genes expres

Chromosome ends in Chironomus tentans do not have long single-stranded overhangs characterizing canonical telomeres.

Single-stranded overhangs of the G-rich strand belong to the conserved features of telomeres composed of short telomeric repeats. These structures are thought to be essential for the maintenance of proper telomeric structure and function and the mechanism of their generation is telomerase-independent. We have examined the presence of single-stranded overhangs in Chironomus tentans, a dipteran inse

Improved fast correlation attacks on stream ciphers via convolutional codes

This paper describes new methods for fast correlation attacks, based on the theory of convolutional codes. They can be applied to arbitrary LFSR feedback polynomials, in opposite to the previous methods, which mainly focus on feedback polynomials of low weight. The results improve significantly the few previous results for this general case, and are in many cases comparable with corresponding resu

The home environment and quality of life-related outcomes in advanced old age: findings of the ENABLE-AGE project

With the present research, we further exploited the potential of the ENABLE-AGE Project, more precisely the Swedish and German data. We hypothesised that the magnitude of accessibility problems (MAP) in the home environment and external housing-related control beliefs (HCB) play a substantial role for a range of outcomes related to quality of life. Our sample at T1 consisted of 847 single-living a

Neutrophils and keratinocytes in innate immunity--cooperative actions to provide antimicrobial defense at the right time and place

The human neutrophil is a professional phagocyte of fundamental importance for defense against microorganisms, as witnessed by the life-threatening infections occurring in patients with neutropenia or with defects that result in decreased microbicidal activity of the neutrophil. Likewise, the skin and mucosal surfaces provide important barriers against infections. Traditionally, these major defens