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Nanowire growth and dopants studied by cross-sectional scanning tunnelling microscopy

Using a crystalline embedding scheme it has recently become possible to study free-standing III - V nanowires with cross-sectional scanning tunnelling microscopy (XSTM). In the present paper we discuss how this novel method can be used for direct atomically resolved imaging of the interior of nanowires. We will focus in particular on two areas where this method provides unique possibilities. First

Seasonal photoreactivity of dissolved organic matter from lakes with contrasting humic content

We studied seasonal variability in photodegradation of dissolved organic carbon (DOC) resulting from artificial ultraviolet-A (UV-A) and UV-B irradiation. Water samples were taken approximately monthly from the surface layers of two oligotrophic lakes with contrasting humic content, situated in southern Sweden. Lake water was filter-sterilized (0.2 μm) and exposed to artificial UV radiation in qua

The challenge of managing patients with polyarteritis nodosa.

Purpose of review In this short review we focus on the problems faced by clinicians caused by the changing definitions of polyarteritis nodosa. Recent findings the term polyarteritis nodosa has been used for more than 100 years as a diagnostic term for patients with systemic vasculitis, however, specific vasculitides have been singled out like branches being chopped off a tree. Now, so little is l

Suppression of limbic motor seizures by electrical stimulation in thalamic reticular nucleus

Kindling is a model of temporal lobe epilepsy in which repeated electrical stimulations in limbic areas lead to progressive increase of seizure susceptibility, culminating in generalized convulsions and the establishment of a permanent epileptic syndrome. We studied here the effect of stimulations in the thalamic reticular nucleus (TRN) on. the development of seizures and hippocampal hyperexcitabi

The MoviText method: Efficient pre-optical reading training in persons with central visual field loss

The MoviText method has been developed and tested on individuals with absolute central scotomas as a pre-optical reading training method. The ZoomText computer screen magnification software with its DocReader feature has been used in reading training to show the effect of moving the text during reading. The user reads with his or her selected eccentric angleviewing in order to acquire the new ecce

Up-regulation of thromboxane A(2) receptor expression by lipid soluble smoking particles through post-transcriptional mechanisms.

Atherosclerosis is a key factor in vascular disease, and cigarette smoking is a well-known risk factor that may induce an inflammatory response and enhance plaque formation in arteries. Thromboxane (Tx) is one key inflammatory mediator involved in the pathogenesis of cardiovascular disease. The present study was designed to test if lipid soluble smoking particles (DSP) enhance TxA(2) receptor (TP)

Complex surface reconstructions solved by ab initio molecular dynamics

Complex surface reconstructions and surface oxides, in particular, often exhibit complicated atomic arrangements, which are difficult to resolve with traditional experimental methods, such as low energy electron diffraction (LEED), surface X-ray diffraction (SXRD) or scanning tunnelling microscopy (STM) alone. Therefore, ab initio density functional calculations are used as a supplement to the exp

Comparison between human and automated electrocardiographic waveform measurements for calculating the Anderson-Wilkins acuteness score in patients with acute myocardial infarction

The Anderson-Wilkins (AW) electrocardiographic (ECG) acuteness score complements time from pain onset in prognostic stratification of patients with acute myocardial infarction (AMI). However, for the AW acuteness score to be of practical use in the acute situation, it must be an integral component of a commercial automated ECG analysis program. The objective of this study was to determine the conc

Revision of the willow catkin flies, genus Egle Robineau-Desvoidy (Diptera: Anthomyiidae), in Europe and neighbouring areas

Egle Robineau-Desvoidy is a modest-sized genus of small blackish anthomyiids with a Holarctic and northern Oriental distribution. They are univoltine, interacting closely with the host plants of their seed-feeding larvae, mainly species of willow (Salix), but also poplar (Populus) and false tamarisk (Myricaria) support some species. Summaries are given of adult and larval habits based on published

Biodegradation and biocompatability of a calcium sulphate-hydroxyapatite bone substitute.

An injectable material consisting of calcium sulphate mixed with hydroxyapatite was investigated as a possible alternative to autograft in the restoration of bone defects. The material was studied both in vitro in simulated body fluid (SBF) and in vivo when implanted in rat muscles and into the proximal tibiae of rabbits. Variation in the strength and weight of the material during ageing in SBF wa

Why are small seeds dispersed through animal guts: large numbers or seed size per se?

Long-distance dispersal of seeds is an important process in metapopulation dynamics and in plant migrations, but at the same time extremely difficult to observe or quantify directly. If seed dispersal ability were related to attributes of seeds or motherplants, long-distance seed dispersal would be predictable by indirect approximation using easy-to-measure traits. Seed size has been suggested to

Specific conditions for enhancement of lipoprotein lipase activity by platelets

Homogenates of human blood platelets, but not of red blood cells, have been found to stimulate lipoprotein lipase activity only when assayed against an emulsified triglyceride substrate sonicated for a short period of time. The degree of stimulation was inversely related to the time of sonication of the substrate. Using chylomicrons as substrate no stimulation of lipoprotein lipase activity by pla

Preferential Interface Nucleation: An Expansion of the VLS Growth Mechanism for Nanowires

A review and expansion of the fundamental processes of the vapor-liquid-solid (VLS) growth mechanism for nanowires is presented. Although the focus is on nanowires, most of the concepts may be applicable to whiskers, nanotubes, and other unidirectional growth. Important concepts in the VLS mechanism such as preferred deposition, supersaturation, and nucleation are examined. Nanowire growth is feas

Isidiate entities in the Teloschistales and their ecological and evolutionary significance.

Thirteen isidiate taxa in the Teloschistales are briefly discussed, i.e. Letrouitia corallina (Müll. Arg.) Hafellner, L. leprolyta (Nyl.) Hafellner, Caloplaca bassiae (Ach.) Zahlbr., C. granulosa (Müll. Arg.) Jatta, C. herbidella (Hue) H. Magn., C. isidiigera Vězda, C. isidiosa (Vainio) Zahlbr., C. littorea Tavares, C. namibensis Kärnef., C. ochraceofulva (Müll. Arg.) Jatta, C. verruculifera (Vain

A geochronological and geochemical study of rocks from Gjelsvikfjella, Dronning Maud Land, Antarctica - implications for Mesoproterozoic correlations and assembly of Gondwana

The Jutulsessen nunataks (72degrees00'S; 2degrees30'E), Gjelsvikfjella, Dronning Maud Land (DML), consist mainly of migmatites of two types. A heterogeneous banded amphibolite facies gneisses; and a more homogeneous part. In the more homogeneous part, partial melts form along axial planes to tight folds. Numerous pegmatitic dykes occur in both migmatites. The homogeneous part of the migmatite has

Migratory birds use head scans to detect the direction of the Earth’s magnetic field

Night-migratory songbirds are known to use a magnetic compass [[13]], but how do they detect the reference direction provided by the geomagnetic field, and where is the sensory organ located? The most prominent characteristic of geomagnetic sensory input, whether based on visual patterns [[47]] or magnetite-mediated forces [[8, 9]], is the predicted symmetry around the north-south or east-west mag