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Scanning tunneling microscopy (STM) and scanning tunneling luminescence were used to correlate the topography with the emission spectra from individual self-assembled, InP quantum dots (QDs). We have investigated in detail how the electric field induced by the STM tip affects the emission from the QDs. This was done when exciting a QD, by altering the bias for constant current, by altering the cur

Uranium atoms activate methane upon ultraviolet excitation to form the methyl uranium hydride CH3-UH, which undergoes alpha-H transfer to produce uranium methylidene dihydride, CH2UH2. This rearrangement most likely occurs on an excited-quintet potential-energy surface and is followed by relaxation in the argon matrix. These simple U + CH4 reaction products are identified through isotopic substitu

Reverse link capacity of a direct-sequence code-division multiple-access (DS-CDMA) system in a multicell environment has been studied recently, and significant capacity improvements due to the use of beamforming have been observed. However, system performance with beamforming will be affected by several impairments, such as direction of arrival estimation errors, array perturbations, mutual coupli

OBJECTIVE: Most parents yearn for a second-trimester ultrasound examination and feel excitement about it, but some also worry about what the examination will show. According to prior research, using only generic instruments or specific questionnaires, anxiety decreases when the ultrasound findings are normal. The aim of this study was to compare parents' worry (Parents' Expectations, Experiences,

A novel traffic flow model based on stochastic microscopic dynamics is introduced and analyzed. Vehicles advance based on the energy profile of their surrounding traffic implementing the "look-ahead" rule and following an underlying asymmetric exclusion process with Arrhenius spin-exchange dynamics. Monte Carlo simulations produce numerical solutions of the microscopic traffic model. Fluctuations

The molar mass and theological properties of an exopolysaccharide (EPS) from Pediococcus damnosus 2.6 were investigated. The molar mass was determined by asymmetrical flow field-flow fractionation coupled with multiangle light scattering and refractive index detection. The EPS was observed to be a flexible chain polymer with a molar mass value of 4 x 10(6) g mol(-1). Heating the sample at 80 degre

An overview of optical techniques for environmental monitoring is presented. Range-resolved measurements of atmospheric pollutants can be performed using the differential absorption lidar technique. Fluorescence lidar allows assessment of vegetation status and also the conditions of the facades of historical buildings. Diode lasers provide particularly realistic schemes for atmospheric gas analysi

The aim of this study was to evaluate the inter- and intra-observer variability and to find differences in diagnostic safety between digital and analog technique in diagnostic zones around hip prostheses. In 80 patients who had had a total hip replacement (THR) for more than 2 years, a conventional image and a digital image were taken. Gruen's model of seven distinct regions of interest was used f

Sediment stratigraphies from three sites, one lake, one overgrown lake, and an exposed section, on the island Tristan da Cunha in the temperate South Atlantic were analysed by means of pollen analysis, total carbon, nitrogen and sulphur content determination, magnetic susceptibility measurements and detailed radiocarbon dating. The aim of these studies was to reconstruct the late Holocene vegetati

We have used time-resolved X-ray diffraction to monitor the resolidification process of molten InSb. Melting was induced by an ultra-short laser pulse and the measurement conducted in a high-repetition-rate multishot experiment. The method gives direct information about the nature of the transient regrowth and permanently damaged layers. It does not rely on models based on surface reflectivity or

Integrin alpha 10 beta 1 is a collagen-binding integrin expressed on chondrocytes. In order to unravel the role of the alpha 10 integrin during development, we generated mice carrying a constitutive deletion of the alpha 10 integrin gene. The mutant mice had a normal lifespan and were fertile but developed a growth retardation of the long bones. Analysis of the skeleton revealed defects in the gro

The intermolecular electrostatic and induction energy of a NEMO potential which includes intramolecular polarization, are compared with a regular NEMO potential and a NEMO potential with configurationally dependent local properties. It is shown that the inclusion of intramolecular polarization improves the description of the intermolecular interactions when using the NEMO potential. (c) 2009 Wiley

The effects of nitrogen ion sputtering and thermal anneal processing on the surface electronic structure of the ternary III-V semiconductor In0.12Ga0.88N have been studied using scanning photoemission microscopy. No phase separation of the material is observed for annealing temperatures up to 650degreesC. However, samples annealed at 700degreesC for 5 h show clear evidence of phase separation. Fur

Objective: To investigate the relationship between memory and intensive care sedation. Design and setting: Prospective cohort study over 18 months in two general intensive care units (ICUs) in district university hospitals. Patients: 313 intubated mechanically ventilated adults admitted for more than 24 h, 250 of whom completed the study. Measurements: Patients (n = 250) were interviewed in the wa

The Gaussian wave model has been successfully used in ocean engineering for more than half a century. It is well understood, and there exists both exact theory and efficient numerical algorithms for calculation of the distribution of safety related wave characteristics, such as crest height and steepness. Its drawback is its lack of realism: it produces waves which are stochastically symmetric, bo

Objective. To search for primary hyperaldosteronism (PHA) among previously known hypertensive patients in primary care, using the aldosterone/renin ratio (ARR), and to evaluate clinical and biochemical characteristics in patients with high or normal ratio. Design. Patient survey study. Setting and subjects. The study population was recruited by written invitation among hypertensive patients in two

Neisseria gonorrhoeae is the causative agent of gonorrhea, a disease that is restricted to humans. Complement forms a key arm of the innate immune system that combats gonococcal infections. N. gonorrhoeae uses its outer membrane porin (Por) molecules to bind the classical pathway of complement down-regulatory protein C4b-binding protein (C4bp) to evade killing by human complement. Strains of N. go

The paper describes briefly the present and future accelerator vacuum systems at MAX-lab, a national laboratory for synchrotron radiation and nuclear physics in Lund, Sweden. The present accelerator systems at MAX-lab, with the 500 MeV MAX I, the 1.5 GeV MAX II, and the 700 MeV MAX III storage rings, contain a variety of different vacuum pumps. In all three storage rings ion pumps and Titanium Sub

Children with specific language impairment (SLI) are often described as having great difficulty with grammatical morphology, but most studies have focused only on these childrens use of verb morphology. In this study, we examined the use of noun phrase (NP) morphology by preschool-age children with SLI who are acquiring Swedish. Relative to typically developing same-age peers and younger peers mat