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Vertical wrap-gated nanowire transistors

We present a process for fabricating a field-effect transistor based on vertically standing InAs nanowires and demonstrate initial device characteristics. The wires are grown by chemical beam epitaxy at lithographically defined locations. Wrap gates are formed around the base of the wires through a number of deposition and etch steps. The fabrication is based on standard III - V processing and inc

Assessment of the impacts of climate change and weather extremes on boreal forests in northern Europe, focusing on Norway spruce

The boreal and boreo-nemoral forests in Europe, which occur in northern and northeastern Europe, are dominated by 2 coniferous species, Norway spruce Picea abies (L.) Karst. being economically the most important one. Forestry is of major economic importance in this region. Forestry planning and climate change scenarios are based on similar (long-term) timescales, i.e. between 70 and 120 yr. Within

Curli, fibrous surface proteins of Escherichia coli, interact with major histocompatibility complex class I molecules

Curli are thin, coiled fibers expressed on the surface of Escherichia coli that bind several matrix and plasma proteins such as fibronectin, laminin, plasminogen, tissue plasminogen activator, and H-kininogen. In this work, we examined the interactions between curli-expressing E. coli and human major histocompatibility complex class I (MHC-I) and class II (MHC-II) molecules. Curliated E. coli was

Neck muscle vibration alters visually-perceived roll after unilateral vestibular loss

Unilateral sternocleidomastoid muscle vibration was applied to 21 normal and six unilateral vestibular deafferented (uVD) human subjects at head erect and during 30 degrees left and right whole body roll-tilt. In normal subjects, neck vibration had no effect upon the settings of a visual bar to subjective visual horizontal (SVH) in any roll-tilt condition. In uVD subjects settings to SVH were sign

Spin-polarized electron tunneling across a Si delta-doped GaMnAs/n-GaAs interface

We study the spin-polarized tunneling of electrons from the valence band of GaMnAs into the conduction band of n-type GaAs with Si delta-doping at the interface. The injection of spin-polarized electrons is detected as circular polarized emission from a GaInAs/GaAs quantum well light emitting diode, corresponding to magneto-optical Kerr effect loops. The angular momentum selection rules are simpli

Mechanical reliability of the Jarvik 2000 Heart - Discussion

Background. Device failure is a limitation of permanent mechanical circulatory support. We studied the mechanical reliability of the Jarvik 2000 Heart, an axial flow pump with ceramic bearings designed to provide more than 10 years' durability. Methods. The Jarvik 2000 Heart was implanted in 102 patients between April 2000 and December 2004. Eighty-three pumps with an abdominal driveline were impl

Fractional moving blood volume measurement using power Doppler ultrasound as an estimation of fetal organ blood perfusion

Fractional moving blood volume (FMBV) estimated using power Doppler ultrasound (PDU) is a sensitive technique to detect slow blood movement. However, several factors as; depth, attenuation and blood characteristics can affect the PDU signals. The aim of this study was to standardized and validate the FMBV measurement compensating for the factors that can affect the final results, in order to accur

Ballistic imaging of the near field in a diesel spray

We have developed an optical technique called ballistic imaging to view breakup of the near-field of an atomizing spray. In this paper, we describe the successful use of a time-gated ballistic imaging instrument to obtain single-shot images of core region breakup in a transient, single hole atomizing diesel fuel spray issuing into one atmosphere. We present a sequence of images taken at the nozzle

CYP1A1 and GSTM1 polymorphisms affect urinary 1-hydroxypyrene levels after PAH exposure

Certain human biotransformation enzymes have been implicated in the formation and scavenging of the ultimate reactive metabolites, the diolepoxides, from polycyclic aromatic hydrocarbons (PAHs). In the present study, performed on aluminum smelter workers, we have analyzed airborne PAH, the pyrene metabolite 1-hydroxypyrene (1-OHP) in urine, and genotypes for biotransformation enzymes involved in P

Green chemistry in perspective - models for GC activities and GC policy and knowledge areas

This article presents two new models that give a perspective on green chemistry (GC). The first model is a classification model of different green chemistry activities, while the second model concerns green chemistry policy and knowledge areas (green chemistry principles, industrial biotechnology and "the green sector"). A broad view of green chemistry is used, where all activities with the aim of

The effect of eight weeks of exercise on knee adduction moment in early knee osteoarthritis - a pilot study.

Objective: Reduced muscle function, causing greater knee joint load, is a potentially modifiable risk factor of knee osteoarthritis (OA). Exercise is an important treatment of knee CA, but the effect on joint load has not been determined. The aim of this study was to investigate the effect of exercise on knee adduction moment during one-leg rise and gait. Design: Patients below age 65 with early s

Speed regulation by in-car active accelerator pedal – Effects on driver behaviour

The long term effects of driving with an active accelerator pedal (AAP) on driver behaviour was studied by using an in car observation method. The AAP produced a counterforce in the accelerator pedal when the speed limit was reached, it could however be overridden by pressing the accelerator pedal harder. Twenty-eight drivers were studied when driving without the AAP and then when driving with the

Beneficial effect from a cognitive training programme on children with acquired brain injuries demonstrated in a controlled study

Primary objective: To test the effectiveness of a cognitive training programme in children and adolescents with attention and memory deficits after acquired brain injury (ABI). Research design: Randomized controlled study. Participants: Thirty-eight children with ABI, 9 - 16 years of age. Methods and procedures: The treatment group trained with the cognitive programme for 30 minutes per day intera

Influence of prior Cd2+ exposure on the uptake of Cd2+ and other elements in the phytochelatin-deficient mutant, cad1-3, of Arabidopsis thaliana

In order to test the potential effect of prior exposure to different Cd concentrations on Cd uptake and accumulation, plants of Arabidopsis thaliana, including a phytochelatin-deficient mutant, cad1-3, and the wild type, were compared. For Cd uptake experiments, plants were grown for 1 week in nutrient solution containing different Cd concentrations (0, 0.05, 0.1, 0.25, 0.5, and 1.0 muM Cd(NO3)(2)