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Density of configurational states from first-principles calculations: The phase diagram of Al-Na surface alloys

The structural phases of AlxNa1-x surface alloys have been investigated theoretically and experimentally. We describe the system using a lattice gas Hamiltonian, determined from density functional theory together with Monte Carlo (MC) calculations. The obtained phase diagram reproduces the experiment on a quantitative level. From calculation of the (configurational) density of states by recently i

On the efficiency of antennas

The fundamental limits of the power efficiency of an antenna are explored. The antenna is confined in a sphere and all of the currents are assumed to run in a material with a conductivity that is a function of the radial coordinate. The analysis is based on the expansion of the electromagnetic fields in terms of vector spherical harmonics. Explicit expressions for the limits of efficiency are deri

Reporting leaders and followers among trajectories of moving point objects

Widespread availability of location aware devices (such as GPS receivers) promotes capture of detailed movement trajectories of people, animals, vehicles and other moving objects, opening new options for a better understanding of the processes involved. In this paper we investigate spatio-temporal movement patterns in large tracking data sets. We present a natural definition of the pattern 'one ob

Effects of l-arginine on cerebral blood flow, microvascular permeability, number of perfused capillaries, and brain water content in the traumatized mouse brain.

It is has been suggested that decreased production of the vasodilatory and anti-aggregative substance NO (nitric oxide) may result in lower cerebral blood flow (CBF) in injured areas of the traumatized brain. The NO-precursor L-arginine has been shown to counteract CBF decreases early after trauma, but microcirculatory and more long-term effects on CBF of L-arginine have not been investigated. In

Subcritical water extraction and beta-glucosidase-catalyzed hydrolysis of quercetin glycosides in onion waste

Onion waste is a renewable raw material, rich in different molecular species of the antioxidant quercetin. To utilize this resource, an environmentally sustainable procedure has been developed, using pressurized hot water to extract the quercetin species, followed by biocatalytic conversion of the quercetin glycosides to quercetin and carbohydrates. Two different recombinantly expressed thermostab

Functional imaging of the frontal lobes in organic dementia. Regional cerebral blood flow findings in normals, in patients with frontotemporal dementia and in patients with Alzheimer's disease, performing a word fluency test

Patterns of functional cortical activation were studied by means of regional cerebral blood flow measurements, performed during rest and during a word fluency task in normal subjects (n = 22), in patients with Alzheimer's disease (n = 17), and in patients with frontotemporal dementia (n = 15). Although all groups showed a significant activation of the Broca's area during word production, the activ

Organization of the ferret lateral cervical nucleus and cervicothalamic tract.

To elucidate the organization of the ferret spinocervicothalamic pathway (SCTP), we examined the lateral cervical nucleus (LCN) and the termination of the cervicothalamic tract (CTY) in this species. In thionin-stained sections, the ferret LCN appeared as an easily delineated column of cells in the dorsolateral funiculus from about mid-C3 to the rostral end of C1, with most cells located in the C1

Mannan-penicillin G acylase neoglycoproteins and their potential applications in biotechnology

Mannan-penicillin G acylase neoglycoproteins were prepared by the conjugation of Saccharomyces cerevisiae mannan with enzyme penicillin G acylase using the reductive amination method. Eight neoglycoproteins preparations were obtained after gel chromatography. The preparations contained from 42 to 67% (w/w) saccharides and their molar masses varied from 283 to over 1000 kDa. Significant biospecific

Improving goniometer accuracy by compensating for individual transducer characteristics

Flexible goniometers are useful for direct movement measurements. Crosstalk due to rotation between the endblocks is well known. However, even without any rotation, some crosstalk can occur. The objective of this study was to elucidate the effect of, and compensate for, the inherent crosstalk in biaxial goniometers, with specific relevance for applications with one dominating movement direction. S

Characterization of microbial activity in soil by use of isothermal microcalorimetry

Isothermal microcalorimetry is now established as a useful technique for the characterization of the microbial activity in soil. A brief summary of publications from this field and of instruments used in such work is presented. Several experimental parameters that can form important sources for systematic errors are discussed and it is suggested that further method work is made in this area. In mo

Hierarchical models of anticipation

Several architectural patterns have been proposed for the purpose of modeling autonomous robots. They do, however, lack support on anticipatory behavior. Anticipatory systems typically consist of hierarchical levels of units with similar structures but with different semantics. Close mapping between units of a reference system and components of software models put high demands on component indepen

Effects of nonionic monomeric and dimeric contrast media on the twitching reaction of the rat. Importance of osmolality and electrolyte content

RATIONALE AND OBJECTIVES. The authors established a rat model of the twitching reaction to contrast media in striated muscle and investigated the influence of nonionic contrast medium on the twitching reaction regarding the nonionic dimer iodixanol compared with the monomer iohexol and the dimer iotrolan. The authors also studied the influences from the electrolyte additions of iodixanol. METHODS.

Ferrous sulphate gel dosimetry and MRI for proton beam dose measurements

Ferrous sulphate gel dosimetry has the potential for measurement of absorbed dose distributions in proton therapy. The chemical properties of the gel are altered according to the radiation dose and these changes can be evaluated in three dimensions using MRI. The purpose of this work was to investigate the properties of a ferrous gel used with clinical proton beams. The gel was irradiated with bot

Aerodynamics, evolution and ecology of avian flight

Animal flight poses intriguing questions about biological adaptation, from how flight could have evolved to the morphological and physiological designs that enable flight to occur. Aerodynamic theory provides ecologists with a useful tool for understanding the basic physics of flight, but analysing flapping flight aerodynamics in birds is difficult, with interesting physiological complications. Re

Isolated soft tissue cleft lip: The influence on the nasal cavity and supernumerary laterals

Objective: The purpose of this investigation was to estimate the vertical deviation of the nasal floor and to register dental disturbances (i.e., hypo- and hyperdontia) in patients with an isolated soft tissue cleft lip. Design: Thirty patients with isolated cleft lips were randomly selected from the files of the Department of Maxillo-Facial Surgery and Jaw Orthopedics. As a matched control group,

Adsorption of Intact Cubic Liquid Crystalline Nanoparticles on Hydrophilic Surfaces: Lateral Organization, Interfacial Stability, Layer Structure, and Interaction Mechanism

Liquid crystalline cubic phase nanoparticles (known as Cubosome), based on glycerol monooleate and stabilized by a nonionic block copolymer (Pluronic F-127), adsorb intact on hydrophilic silica in the presence of an electrolyte, except at high pH. To characterize the nature of the interaction, four techniques were applied in situ: fluorescence microscopy, quartz crystal microbalance with dissipati

Vaccination technique, PPD reaction and BCG scarring in a cohort of children born in Guinea-Bissau 2000-2002

The rates of positive tuberculin skin test (TST) reactions and BCG scarring after BCG vaccination vary between studies and populations. Tuberculin reactivity and BCG scarring may be related to better child survival in low-income countries. We therefore studied determinants for TST reaction and scarring in Guinea-Bissau. In a cohort of children born in suburban Bissau from March 2000 to July 2002,