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Observations and simulations of some divergent-light halos

We deal with some halos generated by the divergent light from a nearby source. After discussing how the divergent light transforms some halo features, we give an outline of a method of handling the simulation of a divergent-light halo. The simulation method is then successfully tested on some well-documented halo observations. We also present a "simulation atlas" that shows halos produced by cryst

The geometric design of micromachined silicon sieve electrodes influences functional nerve regeneration

A neural interface could be used to control a limb prosthesis. Such an interface can be created by facilitating axonal regeneration through a sieve electrode and then register nerve signals intended to control the prosthesis. A key question is how to design the electrodes to ensure the best possible regeneration. Our previous studies have indicated that regeneration can be achieved using electrode

g-factor and exchange energy in a few-electron lateral InGaAs quantum dot

We report on the measurements of the g-factor and the exchange Interaction of electrons in a few-electron lateral quantum dot formed in an InGaAs/InP semiconductor heterostructure. The spin filling sequence of the electron states in the dot is determined by magnetotransport measurements and parallel spin filling configurations are Identified The measured g-factor (for a magnetic field applied para

rd1 Mouse Retina Shows Imbalance in Cellular Distribution and Levels of TIMP-1/MMP-9, TIMP-2/MMP-2 and Sulfated Glycosaminoglycans.

Background: The rd1 mouse retina displays fast degeneration of photoreceptors resulting in a depletion of almost all rod photoreceptors by postnatal day 21 (PN21). To evaluate the role of proteinases in the pathophysiology of this animal model of retinitis pigmentosa, C3H rd1 and congenic wild-type (wt) mice retinas were analyzed. Material and Methods: The cellular localization and levels of prote

Last interglacial atmospheric CO2 changes from stomatal index data and their relation to climate variations

A high-resolution atmospheric CO2 reconstruction based on stomatal index data obtained from Betula and Quercus leaf fragments extracted from the Danish Hollerup lake sediment section provides a unique insight into last interglacial CO2 dynamics. According to pollen stratigraphic correlations the CO2 record covers the first c. 7400 years of the Eemian, as palaeobotanically defined in northwestern E

Oxytocin levels in the posterior pituitary and in the heart are modified by voluntary wheel running

We hypothesized that voluntary wheel running results in increased secretion of oxytocin, a peptide involved in the stress response. An additional hypothesis was that prolonged exercise affects oxytocin levels in the heart, which is in line with the potential role of oxytocin in cardiovascular functions. Voluntary wheel running lasted 3 weeks and daily running distances increased progressively reac

Chemiluminescence sensor for local equivalence ratio of reacting mixtures of fuel and air (FLAMESEEK)

This paper describes a Cassegrain optics-based chemiluminescence sensor (CS) for measurements in gas turbine combustors. The chemiluminescence sensor measures the equivalence ratio of reacting fuel and air mixtures, and can identify the flame location, in partially premixed flames. It has the potential for monitoring the degree of premixedness of reacting fuel and air in industrial gas turbine com

Patient-reported impact of urinary incontinence - Results from treatment seeking women in 14 European countries

Objectives: To describe the patient-reported impact of urinary incontinence (UI) in treatment-seeking women in Europe. Design: PURE was a non-interventional, observational study, which aimed to describe the direct costs of treatment for European women seeking treatment for UI. A secondary Study objective was to describe the impact of UI on health-related quality of life (HRQoL) by UI subtype and s

Coevolution of the domains of cytoplasmic tyrosine kinases

Many signaling molecules are multidomain proteins that have other domains in addition to the catalytic kinase domain. Protein tyrosine kinases almost without exception contain Src homology 2 (SH2) and/or SH3 domains that can interact with other signaling proteins. Here, we studied evolution of the tyrosine kinases containing SH2 and/or SH3 and kinase domains. The three domains seem to have duplica

Surface forces mediated by charged polymers: Effects of intrinsic chain stiffness

The strength and range of surface forces in a system consisting of charged polymers with variable intramolecular stiffness confined between two charged planar surfaces have been investigated by Monte Carlo simulations. The negatively charged surfaces are neutralized by polymers carrying charges of opposite sign. Introducing the intermediate intrinsic stiffness of the chains gives rise to a weaker,

Exact-exchange kernel of time-dependent density functional theory: Frequency dependence and photoabsorption spectra of atoms

In this work we have calculated excitation energies and photoionization cross sections of Be and Ne in the exact-exchange (EXX) approximation of time-dependent density functional theory (TDDFT). The main focus has been on the frequency dependence of the EXX kernel and on how it affects the spectrum as compared to the corresponding adiabatic approximation. We show that for some discrete excitation

Economic evaluation of preconcentration in production of ethanol from dilute sugar solutions

The economic feasibility of preconcentrating dilute sugar solutions prior to fermentation is investigated. Two methods, evaporation and reverse osmosis, are compared. A computer program to determine the optimal preconcentration conditions for glucose solutions of 1.5–16 wt% has been developed. It was used to compute the fractional cost for labor and maintenance, preconcentration, fermentation, and

Cell therapy for Parkinson's disease: problems and prospects.

Cell replacement therapy in Parkinson's disease (PD) has so far been based on the use of primary dopaminergic (DA) neuroblasts obtained from the brain of aborted human fetuses. Clinical trials show that intrastriatal DA neuron transplants can give substantial symptomatic relief in advanced PD patients. Two recent NIH-sponsored placebo-controlled trials, however, have given disappointing results an

The FERRUM project: experimentally determined metastable lifetimes and transition probabilities for forbidden [Ti II] lines observed in eta Carinae

In the spectrum of an emission-line region ejected from the massive star Eta Carinae, called the strontium filament (SrF), forbidden lines from many elements, in particular [Sr II] and [Ti II], are observed. These lines are strong in this specific region and valuable for plasma diagnostics. Forbidden lines are not easily produced in laboratory light sources and the atomic parameters for these line

Helicobacter pylori infection in children in Estonia: Decreasing seroprevalence during the 11-year period of profound socioeconomic changes

Background. The prevalence of Helicobacter pylori infection is inversely associated with socioeconomic conditions in childhood. In Estonia, a high prevalence of H. pylori infection has been observed among children born in 1987 and earlier. Since 1991, after the dissolution of the USSR, profound social and economic changes have taken place in the country. The aim of the study was to evaluate change

Are neuronal markers and neocortical graft-host interface influenced by housing conditions in rats with cortical infarct cavity?

The aim was to study if exposure to an enriched environment influenced graft-host interface and neuronal markers in neocortical grafts implanted in cortical infarct cavities 3 weeks after distal ligation of the middle cerebral artery in adult hypertensive rats. Half the rats were exposed to an enriched environment for 2 h daily 5 days a week starting 1 week after the arterial ligation. The brain w