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Picosecond dynamics of laser-induced strain in graphite

We report on the use of grazing-incidence time-resolved x-ray diffraction to investigate the evolution of strain in natural graphite excited by femtosecond-laser pulses in the fluence range of 6-35 mJ/cm(2). Strains corresponding to up to similar to 2.8% c-axis expansion were observed. We show that the experimental data is in good agreement with calculations based on the Thomsen strain model in co

Uttorkningstider och kritiska fukttillstånd: kemisk fuktbindning och alkalitransport

Två helt olika alternativa möjligheter att förkorta torktiderna för byggfukt i betonggolv har undersökts. Den ena möjligheten var att försöka utnyttja de resultat som erhållits i ett antal tidigare projekt där det visat sig att fuktbelastningen på ett mer eller mindre tätt ytskikt under vissa förhållanden varit mycket lägre efter omfördelning av kvarvarande byggfukt än vad man kunde förvänta sig

Microscopic Colitis is Associated with Several Concomitant Diseases.

Microscopic colitis (MC) is a disease with intestinal mucosal inflammation causing diarrhea, affecting predominantly middle-aged women. The etiology is unknown, but increased prevalence of autoimmune diseases in these patients has been described, although not compared with controls or adjusted for confounding factors. The aim of this study was to examine the prevalence of common diseases in patien

Topics in Machining with Industrial Robots and Optimal Control of Vehicles

Two main topics are considered in this thesis: Machining with industrial robots and optimal control of road-vehicles in critical maneuvers. The motivation for research on the first subject is the need for flexible and accurate production processes employing industrial robots as their main component. The challenge to overcome here is to achieve high-accuracy machining solutions, in spite of strong

Geographic Origin as a Determinant of Carotid Artery Intima-Media Thickness and Brachial Artery Flow-Mediated Dilation. The Cardiovascular Risk in Young Finns Study.

Objective - People living in eastern Finland have approximate to 40% higher coronary heart disease mortality rates than western Finns. Whether this is because of genetic or environmental factors is unknown. We examined the effect of geographic family origin on subclinical atherosclerosis among young Finns. Methods and Results - As part of a longitudinal follow-up study, we measured carotid intima-

General and Abdominal Adiposity and Risk of Death in Europe

BACKGROUND Previous studies have relied predominantly on the body-mass index (BMI, the weight in kilograms divided by the square of the height in meters) to assess the association of adiposity with the risk of death, but few have examined whether the distribution of body fat contributes to the prediction of death. METHODS We examined the association of BMI, waist circumference, and waist-to-hip ra

Stability of thiuram disulfides in patch test preparations and formation of asymmetric disulfides

The thiuram mix used in patch testing originally contains 4 compounds. However, chemical analysis of the test preparation revealed that several new compounds are spontaneously formed during storage. The structures of these compounds have been determined and the rate of their formation has been studied in buffer solution at pH 7.4. After a few hours, a large amount of mixed disulfides are formed in

Dephasing and ac oscillations in an open Aharanov-Bohm ring

We have studied the tunneling current in an open ring system enclosing a magnetic flux which may have an ac component. Analytic expressions for the time-averaged tunneling current have been obtained, which suggest two possible experiments to determine the temperature dependence of the dephasing rate. We have also discovered a new phenomenon that with a given dc magnetic flux, the Current is an osc

Neurobehavioral deficits in young adult offspring with heightened risk for psychosis who developed schizophrenia-spectrum disorder

Neurobehavioral deficits in neuromotor function, verbal memory, executive function and attention found in patients with schizophrenia and their relatives have been suggested to be liability indicators or predictors of schizophrenia. It remains uncertain which of these neurobehavioral deficits are components of the illness itself or characteristics associated with genetic risk for it. The purpose o

Energy-momentum tensor for a scalar Casimir apparatus in a weak gravitational field: Neumann conditions

We consider a Casimir apparatus consisting of two perfectly conducting parallel plates, subject to the weak gravitational field of the Earth. The aim of this paper is the calculation of the energy-momentum tensor of this system for a free, real massless scalar field satisfying Neumann boundary conditions on the plates. The small gravity acceleration (considered here as not varying between the two

Changes in the LIS Research Front: Time-Sliced Cocitation Analyses of LIS Journal Articles, 1990–2004

Based on articles published 1990-2004 in 21 LIS journals, a set of co-citation analyses were performed to study changes in research fronts over the last 15 years, where LIS is at now; and to discuss where it is heading. To study research fronts, here defined as current and influential co-cited papers, a citations among documents methodology was applied; and to study changes, the analyses were time

The Charge Capacitance of the Chemical Bond: Application to Bonds Containing Metals

The charge capacitance of metal containing complexes are studied. For molecules with multiple bonding between the metal atoms it is found that the charge capacitance is correlated to the maximum bond order, natural bond order, and to some extent the effective bond order. Furthermore the charge capacitance of some methylidene metal dihydride complexes are studied. These molecules have agostic inter

Relationship between sex pheromone elicited behaviour and response of single olfactory receptor neurones in a wind tunnel

Responses from pheromone-specific receptor neurones in male Agrotis segetum (Denis & Schiffermuller) (Lepidoptera: Noctuidae) were recorded in a laboratory wind tunnel. Stimuli were: (1) rubber septum dispensers loaded with single components or a four-component pheromone blend, (2) excised glands from female A. segetum, (3) constrained A. segetum females with extruded glands. Dose-response cur

Reed warbler orientation: initiation of nocturnal migratory flights in relation to visibility of celestial cues at dusk

We used radiotelemetry to investigate the time of migratory flight initiation relative to available celestial orientation cues and departure direction of a nocturnal passerine migrant, the reed warbler, Acrocephalus scirpaceus, during autumn migration. The study was carried out at Falsterbo, a coastal site in southwest Sweden. The warblers initiated migration from times well after local sunset and

Oncoretroviral gene transfer to NOD/SCID repopulating cells using three different viral envelopes

Background The aim of this study was to investigate gene transfer to human umbilical cord blood (CB) CD34(+)/CD38(low) and NOD/SCID repopulating cells using oncoretroviral vectors and to compare the transduction efficiency using three different viral envelopes. Methods CB cells were transduced on Retronectin using an MSCV-based vector with the gene for GFP (MGIN), which was packaged into three dif

Links between worlds: unraveling migratory connectivity

Migration is the regular seasonal movement of animals from one place to another, often from a breeding site to a nonbreeding site and back. Because the act of migration makes it difficult to follow individuals and populations year round, our understanding of the ecology and evolution of migrating organisms, particularly binds, has been severely impeded. Exciting new advances in satellite telemetry

Importance of the organic aerosol fraction for modeling aerosol hygroscopic growth and activation: a case study in the Amazon Basin

The aerosol in the Amazon basin is dominated throughout the year by organic matter, for the most part soluble in water. In this modeling study, we show how the knowledge of water-soluble organic compounds (WSOC) and the associated physical and chemical properties (e.g. solubility, surface tension, dissociation into ions) affect the hygroscopic growth and activation of the aerosol in this area. The

Fluorescence investigations to classify malignant laryngeal lesions in vivo.

BACKGROUND:: The extent of surgical resection for malignant laryngeal lesions influences voice quality. An instrument to estimate histopathologic grading of dysplasia in vivo may spare normal tissue without increasing the risk of local failure. METHODS: Laryngeal lesions (N = 39; 21 after administration of delta-aminolevulinic acid (ALA)) were investigated with laser-induced fluorescence, and the