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Effect of aspect ratio on entropy generation in a rectangular cavity with differentially heated vertical walls

In the present study, entropy generation in rectangular cavities with the same area but different aspect ratios is numerically investigated. The vertical walls of the cavities are at different constant temperatures while the horizontal walls are adiabatic. Heat transfer between vertical walls occurs by laminar natural convection. Based on the obtained dimensionless velocity and temperature values,

Time-dependent reproductive decisions in the blue tit

Many breeding attempts in birds do not result in any fledged young due to predation on eggs or young. Consequently, the influence of time constraints on reproductive decisions are integrated parts of the reproductive behaviour of birds breeding within short, seasonal climate zones. In this study. I mimicked nest predation by removing blue tit (Parus caeruleus) clutches shortly after completion. Ar

In vitro studies of the pharmacodynamics of teicoplanin against Staphylococcus aureus, Staphylococcus epidermidis and Enterococcus faecium

Objective To investigate the basic pharmacodynamic properties of teicoplanin in vitro for Staphylococcus aureus, Staphylococcus epidermidis and Enterococcus faecium. Methods The following experiments were performed: (1) bacterial killing by teicoplanin at different concentrations; (2) bacterial killing by teicoplanin at 8 x MIC against the same strains with inocula of 5x10(3), 5x10(5) and 5x10(7)

Ecological half-time of radiocesium from Chernobyl debris and from nuclear weapons fallout as measured in a group of subjects from the south of Sweden

From 1960 to 1980 and between 1987 and 1994 the whole-body content of 17Cs, and when possible also 134Cs, was measured in a group of subjects living in the city of Lund, Sweden (55.7 degrees N, 13.2 degrees E). The results have been analyzed to estimate the effective ecological half-time of fallout radiocesium in humans living in the area. The Lund area (The Province of Skane) was subjected to a d

Toward a stem cell gene therapy for breast cancer

Current approaches for treatment of late-stage breast cancer rarely result in a long-term cure. In part this is due to tumor stroma that prevents access of systemically or intratumorally applied therapeutics. We propose a stem cell gene therapy approach for controlled tumor stroma degradation that uses the pathophysiologic process of recruitment of inflammatory cells into the tumor. This approach

Water activity and substrate concentration effects on lipase activity.

Catalytic activity of lipases (from Rhizopus arrhizus, Canadida rugosa, and Pseudomonas sp. was studied in organic media, mainly diisopropyl ether. The effect of water activity (a(w)) on V(max) showed that the enzyme activity in general increased with increasing amounts of water for the three enzymes. This was shown both for esterification and hydrolysis reactions catalyzed by R. arrhizus lipase.

Isozyme evidence of relationships within Sphagnum sect. Acutifolia (Sphagnaceae, Bryophyta).

Ten enzyme systems coding for 13 putative loci were studied in 12 European species of Sphagnum sect. Acutifolia (peat mosses). On average seven plants from each of 73 collections made throughout N Europe were analysed. Despite complex morphological variation, all species expressed unique allele combinations. Principal components and cluster analyses based on allele frequencies showed that sect. Ac

A theoretical model of parents' experiences of threat of preterm birth in Sweden.

Objective: to gain a deeper understanding of both parents' experiences during the mother's stay in hospital for threat of an early delivery and eventual preterm birth. Design: explanatory design with separate interviews for mothers and fathers using the grounded theory method. Setting: University Hospital in southern Sweden. Participants: 17 mothers and six fathers, who had experienced a thr

Evidence for the existence of the [202]3/2 deformed band in mirror nuclei Mg-25 and Al-25

After 50 years of its prediction, the highest-lying [2 0 2]3/2 orbit among the six Nilsson single-particle orbits originating from the sd shells in prolately deformed nuclei and the rotational band on this orbit were identified. The band members were observed in Al-25 at excitation energies of 6-7.5 MeV in a high-resolution Mg-25(He-3,t) charge-exchange reaction at 0degrees having a strong selecti

Simulation of soil chemistry and nutrient availability in a forested ecosytem of southern Quebec. Part II. Application of the SAFE model

The dynamic soil model SAFE was calibrated and validated in a small hardwood forest of southern Quebec as a function of its ability to reproduce current soil chemistry and similar pre-industrial soil conditions despite the difference in forest history. SAFE was relatively accurate for reproducing soil chemistry, but comparison of pre-industrial soil conditions between unburned and burned stands ca

Risk factors for local recurrence after breast-conserving surgery

Background: It is not clear whether risk factors for local recurrence after breast-conserving surgery differ in women having surgery for in situ or invasive cancer. Furthermore, the Nottingham Prognostic Index (NPI) and Nottingham Histological Grade (NHG) have been little studied as determinants of local recurrence risk. Method: In a case-control study (491 cases and 1098 controls) nested within a

Quantitative single photon emission tomography: verification for sources in an elliptical water phantom

Accurate absorbed dose calculations are important for a proper dose planning in internal radionuclide therapy. The activity distribution must be measured and the target volume defined. This can be done with single photon emission tomography (SPET) if proper attenuation and scatter correction are employed. This study investigated the calculation of the activity and the volume of different spherical

YjbH is a novel negative effector of the disulphide stress regulator,Spx, in Bacillus subtilis.

In the soil bacterium Bacillus subtilis Spx is a key regulator that controls expression, positively or negatively, of several genes in response to certain oxidative stresses that lead to the formation of unwanted disulphide bonds. Here we characterized the yjbH gene and show that it encodes a novel effector of Spx. The yjbH gene is part of the yjbIH operon that encodes a truncated haemoglobin (Yjb

Peer-group support intervention improves the psychosocial well-being of AIDS orphans: Cluster randomized trial

Accumulating evidence suggests that AIDS orphanhood status is accompanied by increased levels of psychological distress such as anxiety, depression, intense guilt, shame, and anger. However, few studies have examined the possible reduction of psychological distress in AIDS orphans through the help of interventions that promote well-being. The objective of the study was to evaluate the effects of a

Mental disorders and DSM-IV paedophilia in 185 subjects convicted of sexual child abuse

The objective of this study was to explore how sexual child abusers who meet the DSM-IV criteria for paedophilia differ from those who do not. We studied DSM-IV disorders and paedophilic interests in all cases of sexual child abuse referred to forensic psychiatric investigation in Sweden between 1993 and 1997 (n = 185). Frequency and severity of other mental disorders did not differ between subjec

Associations between malaria and MHC genes in a migratory songbird

Malaria parasites are a widespread and species-rich group infecting many wild populations of mammals, birds and reptiles. Studies on humans have demonstrated that genetic factors play a key role in the susceptibility and outcome of malaria infections. Until the present study, it has not been examined whether genetic variation in hosts is important for the outcome of malaria infections in natural a

Biological record of added manganese in seawater: a new efficient tool to mark in vivo growth lines in the oyster species Crassostrea gigas

The biological response of increased manganese in seawater was tested experimentally with the oyster species Crassostrea gigas by adding, once per day, a fixed quantity of MnCl2 to the container where the oysters were living. Uptake of Mn2+ in the shell was traced with cathodoluminescence and quantified with a high spatial resolution proton microprobe. The daily addition of MnCl2 resulted in the v

Pressure-induced protein unfolding in the ternary system AOT-octane-water is different from that in bulk water

In a cellular environment, the presence of macromolecular cosolutes and membrane interfaces can influence the folding-unfolding behavior of proteins. Here we report on the pressure stability of alpha-chymotrypsin in the ternary system bis(2-ethylhexyl)sodium sulfosuccinate-octane-water using FTIR spectroscopy. The ternary system forms anionic reverse micelles which mimic cellular conditions. We fi