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The degradation effect boron doped and oxygen-rich crystalline silicon materials suffer from under illumination can be neutralized in hydrogenated silicon by the application of a regeneration process consisting of a combination of slightly elevated temperature and carrier injection. In this paper, the influence of variations in short high temperature steps on the kinetics of the regeneration process is investigated. It is found that hotter and longer firing steps allowing an effective hydrogenation from a hydrogen-rich silicon nitride passivation layer result in an acceleration of the regeneration process. Additionally, a fast cool down from high temperature to around 550 °C seems to be crucial for a fast regeneration process. It is suggested that high cooling rates suppress hydrogen effusion from the silicon bulk in a temperature range where the hydrogenated passivation layer cannot release hydrogen in considerable amounts. Thus, the hydrogen content of the silicon bulk after the complete high temperature step can be increased resulting in a faster regeneration process. Hence, the data presented here back up the theory that the regeneration process might be a hydrogen passivation of boron-oxygen related defects. [ABSTRACT FROM AUTHOR]

Background and purpose: Neuroinflammation has been proposed as part of the pathogenesis of post‐concussion symptoms (PCS), but the inflammatory response of the human brain to mild traumatic brain injury (mTBI) remains unknown. We hypothesized that a neuroinflammatory response is present in mTBI at 1–2 weeks post‐injury and persists in patients with PCS. Methods: We scanned 14 patients with mTBI without signs of structural damage at 1–2 weeks and 3–4 months post‐injury and 22 healthy controls once using the single photon emission computed tomography tracer 123I‐CLINDE, which visualizes translocator protein (TSPO), a protein upregulated in active immune cells. PCS was defined as three or more persisting symptoms from the Rivermead Post Concussion Symptoms Questionnaire at 3 months post‐injury. Results: Across brain regions, patients had significantly higher 123I‐CLINDE binding to TSPO than healthy controls, both at 1–2 weeks after the injury in all patients (P = 0.011) and at 3–4 months in the seven patients with PCS (P = 0.006) and in the six patients with good recovery (P = 0.018). When the nine brain regions were tested separately and results were corrected for multiple comparisons, no individual region differed significantly, but all estimated parameters indicated increased 123I‐CLINDE binding to TSPO, ranging from 2% to 19% in all patients at 1–2 weeks, 13% to 27% in patients with PCS at 3–4 months and −9% to 17% in patients with good recovery at 3–4 months. Conclusions: Neuroinflammation was present in mTBI at 1–2 weeks post‐injury and persisted at 3–4 months post‐injury with a tendency to be most pronounced in patients with PCS. [ABSTRACT FROM AUTHOR]

Rapid HIV testing may circumvent the practical barriers to HIV testing in several settings. User preference of the testing kits available has been relatively underexplored. We examined healthcare provider (HCP) ratings of two validated rapid testing kits in clinical practice. From 1 July to 1 December 2012 we prospectively recruited HCPs (clinic nurses) from three outpatient clinics linked to Lausanne University Hospital, Lausanne, Switzerland. The HCPs had experience in taking blood samples but varying experience in rapid HIV testing. Participating HCPs performed rapid HIV testing using Determine™ Combo (DETE) or INSTI™ (INSTI), according to a predefined randomization sequence, and rated practical aspects of each test using a Likert scale. Seventeen HCPs of 23 approached (74%) were eligible and agreed to participate, performing a total of 336 HIV tests. Globally, the testing procedure was rated as easy or very easy by 97% (DETE) to 99% (INSTI) of tests performed. Among experienced HCPs, DETE was rated easier than INSTI for kit storage (p < 0.001) and blood collection ( P = 0.012) while INSTI was rated easier than DETE for blood application ( P = 0.001) and test interpretation ( P = 0.005). Among less experienced HCPs, both tests performed equally with the exception of test interpretation ( P < 0.001) and overall ease of use ( P = 0.05) in favour of INSTI. Of all HCPs, 94% stated they would recommend INSTI over DETE based on the time to result, ease of test interpretation and overall ease of use. Rapid HIV testing was considered easy to perform, even by inexperienced nursing staff. Whilst both tests were considered easy to use, the HCPs in this study preferred INSTI to DETE overall, due to rapid time to result, ease of test interpretation and general ease of use. [ABSTRACT FROM AUTHOR]

Rhodococcus equi is a facultative intracellular bacterium causing severe pyogranulomatous pneumonia, ulcerative enterocolitis, and mesenteric lymphadenopathy in foals aged less than 6 months. Less frequently, this pathogen affects various other species, such as pigs, cattle, cats, and even humans. Although rhodococcosis is treated with a combination of antimicrobial agents, resistance is developed in some cases, and thus, antimicrobial susceptibility must be monitored and managed. Considering these limitations of the current therapy and unavailability of a vaccine to prevent the disease, research is particularly focused on the development of an effective vaccine against rhodococcosis. Most vaccines undergoing development utilize the virulence-associated protein (Vap) A antigen, which was identified previously as a key virulence factor of R. equi. Nevertheless, other proteins, such as VapG, present in most virulent R. equi strains, are also encoded by vap genes located on the R. equi bacterial virulence plasmid. In the present study, we evaluated the effect of VapG immunization on the survival of R. equi-challenged mice. We used attenuated Salmonella as a carrier for VapG (Salmonella-vapGC), a procedure previously adopted to develop a VapA-based vaccine. We observed that vaccination with Salmonella-vapGC induced both an increased IFN-g, IL-12, and TNF-a production, and a decreased bacterial burden in organs of the R. equi-challenged mice. Nevertheless, SalmonellavapG C vaccination protected only 50% of the mice challenged with a lethal dose of R. equi. Interestingly, we observed an increased frequency of B cells in the spleen of Salmonella-vapGC-vaccinated mice and showed that Salmonella-vapGC-vaccinated R. equi-challenged B-cell-knockout mice did not reduce the bacterial burden. Given these results, we discussed the potential role of the humoral immune response induced by Salmonella-vapGC vaccination in conferring protection against R. equi infection, as well as the employment of VapG antigen for obtaining hyperimmune plasma to prevent rhodoccocosis in young foals. [ABSTRACT FROM AUTHOR]

The suspension plasma spraying (SPS) process has been developed to permit the feeding of sub-micrometer-sized powder into the plasma plume. In contrast to electron beam-physical vapor deposition and plasma spray-physical vapor deposition, SPS enables the cost-efficient deposition of columnar-structured coatings. Due to their strain tolerance, these coatings play an important role in the field of thermal barrier coatings (TBCs). In addition to the cost-efficient process, attention was turned to the TBC material. Nowadays, yttria partially stabilized zirconia (YSZ) is used as standard TBC material. However, its long-term application at temperatures higher than 1200 °C is problematic. At these high temperatures, phase transitions and sintering effects lead to the degradation of the TBC system. To overcome those deficits of YSZ, Mg-Al-spinel was chosen as TBC material. Even though it has a lower melting point (~2135 °C) and a higher thermal conductivity (~2.5 W/m/K) than YSZ, Mg-Al-spinel provides phase stability at high temperatures in contrast to YSZ. The Mg-Al-spinel deposition by SPS resulted in columnar-structured coatings, which have been tested for their thermal cycling lifetime. Furthermore, the influence of substrate cooling during the spraying process on thermal cycling behavior, phase composition, and stoichiometry of the Mg-Al-spinel has been investigated. [ABSTRACT FROM AUTHOR]

Introduction: Olivine is one of the major minerals in chondritic meteorites and occurs in all chondritic components, including amoeboid olivine aggregates (AOAs), forsterite-bearing Type B (FoB) Ca,Al-rich inclusions (CAIs), chondrules, and matrices (e.g., [1-4]). As a result, olivines could preserve chemical and isotopic characteristics of their formation environments. There are significant variations in oxygen isotopic compositions of chondritic olivine. Forsteritic olivine in AOAs and FoB-CAIs has solar-like 16O-rich compositions (D17O ~ -23±2‰); the former condensed from an 16O-rich gas of ~solar composition, whereas the latter crystallized from remelted condensates in an isotopic similar gaseous reservoir. Olivine phenocrysts in chondrules are significantly 16O-depleted compared to CAIs and AOAs: D17O ranges from ~ -7 to +3‰. Only rare relict olivines in chondrules have CAI/AOA-like 16O-rich compositions; these grains most likely represent fragments of CAIs and AOAs incompletely melted during chondrule formation (e.g., [5]). Olivine in matrices of weakly metamorphosed meteorites is extremely fine-grained (<100 nm) and has predominantly forsteritic composition. In metamorphosed chondrites, matrix olivines are coarse-grained (up to 10 μm) and enriched in FeO. Due to small grain sizes, oxygen isotopic compositions of matrix olivines are poorly known. Mapping of matrices of Vigarano [6] and Kakangari [7] using isotope microscopes (secondary ion mass-spectrometer (SIMS) plus SCAPS detector) revealed the presence of 16O-rich olivine grains. While most matrix olivines in Vigarano have 16O-poor compositions, nearly half of olivines measured in Kakangari matrix are 16O-rich. Here, we present for the first time new lithologies largely composed of 16O- and Fe-rich olivine. We attempt to address the question of whether these 16O-rich olivine grains were formed by condensation in the solar nebula or by a secondary process during the evolution of the parent body. Mineralogical characteristics of these unusual olivines, as well as in-situ measured oxygen-isotope compositions of different phases are reported in detail. Samples and analytical methods: The new lithologies occur as large clasts in two different ordinary chondrites: Northwest Africa 5206 (LL3) and Northwest Africa 6925 (L3) Scanning electron microscopy (SEM) and electron microprobe analysis (EMPA) were performed at the University of Münster. Two electron-transparent lamellae from one clast were prepared using a Zeiss CrossBeam 340 focused ion beam system (FIB). Subsequent transmission electron microscope (TEM) analyses were performed using an aberration-corrected Thermo Scientific "Themis" (300 kV). In-situ oxygen isotope analyses in olivine were carried out using SIMS at both the University of Heidelberg (Cameca ims-1280 HR) and the University of Hawai'i (Cameca ims-1280). In-situ trace and rare earth element (REE) concentrations were measured by inductively coupled mass spectrometry by laser ablation (LA-ICP-MS). Results and discussion: The lithologies consist mainly of FeO-rich olivine (Fa~34) ranging from a few up to ~20µm, hydrous amphiboles (intergrowth of tremolite and cummingtonite), phyllosilicates, and some Fe-Ni metal and Fe-Ni sulfides. FeO-rich olivine represents the major phase (~60 vol.%) forming the matrix, and commonly occurs as rounded objects (enclosing amphiboles), similar to donut-shaped AOAs with metal or sulfide inside. In addition, fragments of 2 POP chondrules (16O-poor) were found in both clasts. The clasts show flat CI-normalized REE patterns (~1.4 x CI). Oxygen-isotopic compositions in FeO-rich olivine grains plot along ~slope-1 line in 3O-isotope diagram, ranging from ~-25 to ~3? in D17O; by far most olivines have ?17O ~-24?, consistent with typical CAIs and AOAs. Some olivines have positive D17O values similar to chondrules in ordinary and R chondrites. The others have intermediate D17O values. The 16O-rich and 16O-depleted olivines have similar Fa contents (~34 mol%). The 16O-rich olivines are texturally and isotopically similar to olivines in AOAs and most likely condensed directly in the early solar nebula at high temperatures. Subsequently they accreted together with less 16O-rich olivines and water ices (as indicated by abundant hydrated phases), and experienced Fe-Mg interexchange during fluid-assisted thermal metamorphism in an asteroidal setting but largely escaped from O-isotope equilibration. The extremely high proportion of 16O-rich condensates in the clasts may suggest their early accretion either in the inner or outer disk. Bulk Cr and Ti isotopic compositions of the clasts may help to understand their genetic relationship to carbonaceous or noncarbonaceous meteorites. This work is in progress. [ABSTRACT FROM AUTHOR]

Introduction: Meteorites carry the cosmological information and history of the first particles formed, evolved, and accreted into larger planetesimals. Refractory inclusions [Ca,Al-rich inclusions (CAIs) and amoeboid olivine aggregates (AOAs)] are considered to be the oldest components [1] and are embedded together with chondrules, metals, and sulfides within matrix materials of chondrites. The connection between CAIs and chondrules has been insufficiently clarified until today. Ebert and Bischoff [2] showed that Na-Al-rich chondrules, a variety of Al-rich chondrules [3,4], have volatility controlled bulk rare earth element (REE) patterns, similar to CAIs [5]. Ebert and Bischoff suggested that CAIs or CAI-like material were a main part of the precursor material for Al-rich chondrules. However, the Al-rich chondrules in ordinary chondrites (OCs) show no enrichment in 50Ti, which is in contrast to Al-rich chondrules from CO chondrites and CAIs from carbonaceous and ordinary chondrites [6]. They concluded that a refractory precursor - similar in mineralogy, but different in their 50Ti - was part of the precursor of these chondrules in OCs. To gain more information about the origin of the Al-rich chondrule's precursor, additional mineralogical, petrological, and oxygen isotopic investigations on Al-rich chondrules from unequilibrated OCs and the CO3.1 chondrite Dar al Gani (DaG) 083 were performed. Results: 17 Al-rich chondrules from unequilibrated OCs and 4 Al-rich chondrules from DaG 083 were investigated. The Al-rich chondrules consist of olivine, low- and high-Ca pyroxenes, and, occasionally, spinel phenocrysts embedded in Na-rich mesostasis. In one chondrule, hibonite is also present. Al-rich chondrules from OCs have heterogeneous oxygen isotopic compositions with Δ17O values ranging from -4.5 to +5.8‰, but no 16O-enriched (Δ17O < -20 ‰) relict grains are found (Fig. 1). Their O-isotope heterogeneity is mineralogically controlled: chondrules glassy mesostasis is 16O-depleted compared to chondrule phenocrysts, which themselves have a homogeneous O-isotope composition within an individual chondrule. The Al-rich chondrules from the CO3.1 chondrite DaG 083 have a heterogeneous O-isotope composition with Δ17O ranging from -24.6 to -0.3 ‰. Discussion and Conclusions: The vast majority of the investigated Al-rich chondrules have heterogeneous O-isotopic compositions: Chondrule glasses are 16O-depleted compared to chondrule phenocrysts. The 17O values of chondrule glasses in unequilibrated OCs approach those of aqueously-formed fayalite and magnetite, ~ +5‰ [7]. We infer that the chondrule glasses experienced O-isotopic exchange with an aqueous fluid on the OC parent asteroids. One Alrich chondrule from DaG 083 contains relict spinel grains with a Δ17O value of -24.3±1.3‰, indicative of 16O-rich precursor refractory material, similar to CAIs and AOAs. No relict grains were present within Al-rich chondrules from OCs. However, embedded phenocrysts prevent totally equilibration with the surrounding gas during chondrule formation and are still 16O-enriched with Δ17O values ranging from -4.5 to -1.3‰. Therefore, the OC region cannot be the formation region of the Al-rich chondrule precursor material. The relict grain, in an Al-rich chondrule from the CO3 chondrite, with a similar O-isotopic composition as CAIs/AOAs [8] and the in general 16O-enriched phenocrysts in Al-rich chondrules from OCs and the CO clearly show the present of refractory material similar to CAIs/AOAs, which were part of the Al-rich chondrule's precursor materials. [ABSTRACT FROM AUTHOR]

Introduction: Ca,Al-rich inclusions (CAIs) are the oldest solids formed in our solar system ~4.567 Ga, most likely close to the proto Sun [1], providing a window for examining the earliest isotopic reservoir(s) in this region and how that reservoir(s) evolved through time. The vast majority of CAIs in unmetamorphosed carbonaceous chondrites (petrologic types 1-3.0) have uniform Δ17O whithin individual CAIs, but show inter-CAI variations from -40‰ to -5‰, suggesting variable O-isotope composition of the nebular gas in the CAI-forming region [e.g., 2]. Here, we reevaluate previous data [3] with new investigations from a unique and well-rounded Zn-rich CAI from the CO3.1 carbonaceous chondrite Dar al Gani (DaG) 083 (Fig. 1a). Results: The CAI core consists of finegrained Zn-hercynite (7.4 wt% ZnO). The core is surrounded by a double-layered rim of grossite and spinel with tiny inclusions of perovskite. The rim is surrounded by a wrinkled layer of Ca-pyroxene with minor melilite. The CAI has a heterogeneous O-isotopic composition (Figs. 1c,d): Ca-pyroxene is the most 16O-rich mineral (Δ17O ~ -23‰). Spinel is 16O-depleted relative to the pyroxene (Δ17O ~ -14‰). Zn-hercynite, grossite, and melilite have similar 16O-poor compositions within uncertainties (Δ17O ~ -3±2‰). The rare earth elements (REEs) have been measured in Znhercynite and grossite (Fig. 1b). Compared to CI, Gd is up to 35‰ enriched, whereas Ce is strongly depleted in both minerals. This kind of pattern is known for HAL-type refractory inclusions [4]. However, the enrichment of light REEs with a smooth decrease in the heavy REEs that is characteristic to other HAL-type objects is not clear in the DaG 083 CAI. In addition, a depletion of Sm, Eu, Ho, and Er to their neighboring elements is observed Discussion and Conclusions: The DaG 083 CAI studied is not only a remarkable sample because of its texture and mineralogy but also by its O-isotopic composition and extraordinary REE-pattern. The REE patterns suggests the CAI formed under variable redox conditions. Under oxidizing conditions, Ce and Pr become volatile, which could be responsible for the large depletion of Ce. However, Eu, Sm, Ho, and Er are also depleted and these four elements become volatile under reducing conditions. Therefore, the CAI underwent either two heating events under different oxygen fugacity or a single heating with evolving fO2 [5]. The CAI was still within the CAI formation region close to the proto Sun as indicated by the outermost Ca-pyroxene having solar-like 16O-rich composition. Melilite, grossite, and the Zn-hercynite are depleted in 16O. Their Δ17O values are similar to that of an aqueous fluid on the CO parent asteroid (Δ17O ~ -1‰) inferred from O-isotope composition of aqueously formed magnetite and fayalite [6,7]. We infer that these minerals experienced post-crystallization O-isotope exchange with the fluid [8]. Zn-rich hercynite most likely formed by replacement of krotite and/or grossite during aqueous alteration [e.g. CaAl2O4(s) + xZn(aq) + (1-x)Fe(aq) = (Fe,Zn)Al2O4(s) + Ca(aq); the origin of Zn will be part of future investigations]. The Mg-rich composition of the spinel rim suggests that the alteration occurred at low temperature that prevented significant Fe-Mg interexchange in it. Spinel and Ca-pyroxene are resistant to O-isotope exchange by parent body alteration. Therefore, the intermediate O-isotopic composition of spinel is primary and provides a clear evidence for variations in O-isotopic composition of nebular gas in the CAI-formation region.. [ABSTRACT FROM AUTHOR]

Aim The purpose of this study was to determine the effect of eccentric muscle damage on muscle activation patterns and intermuscular coherence during a fatiguing isometric contraction involving the elbow flexor muscles. Methods Ten young subjects participated in three experimental sessions that involved the performance of maximum voluntary contractions ( MVCs), a constant-force task at 30% MVC, and a fatiguing isometric contraction at 30% MVC. The three sessions were performed before, 2 h after and 2 days after eccentric exercise to induce muscle damage in elbow flexor muscles. Task performance was quantified with electromyography ( EMG) from the elbow flexor (biceps brachii, brachialis and brachioradialis) and extensor (triceps brachii) muscles, M-wave amplitude of biceps brachii, elbow flexor force fluctuations and endurance time of a fatiguing contraction. Intermuscular coherence during the fatiguing contraction was quantified from the rectified surface EMGs between muscle pairs. Results Eccentric exercise resulted in several indicators of muscle damage, such as a prolonged decline in muscle strength and an increase in muscle soreness 2 days after exercise. A 29% reduction in endurance time was observed 2 h after eccentric muscle damage, which returned to baseline 2 days later. The reduced endurance time 2 h after muscle damage was accompanied by an increase in EMG- EMG coherence between biceps brachii and brachialis muscles, which was observed at the end of the fatiguing contraction. Conclusion These findings suggest that eccentric muscle damage produces a decrease in endurance time that is accompanied by an increase in intermuscular coherence in the presence of fatigue. [ABSTRACT FROM AUTHOR]

We describe the design of the Sunrise Filter Imager (SuFI) and the Image Stabilization and Light Distribution (ISLiD) unit onboard the Sunrise balloon borne solar observatory. This contribution provides the necessary information which is relevant to understand the instruments' working principles, the relevant technical data, and the necessary information about calibration issues directly related to the science data. [ABSTRACT FROM AUTHOR]

Ab initio calculations of the superconducting properties have been performed for zirconium and hafnium nitrides at normal and high pressures. The results for ZrN are in good agreement with the existing data of the tunnel experiments and measurements of the pressure derivative of the critical temperature T c. It has been shown that the decrease in T c under compression occurs due primarily to an increase in the phonon frequencies. [ABSTRACT FROM AUTHOR]

We report ab initio linear-response calculations of the phonon spectra and the electron-phonon interaction for several transition metal carbides and nitrides in a NaCl-type structure. For NbC, the kinetic, optical, and superconducting properties are calculated in detail at various pressures and the normal-pressure results are found to agree well with the experiment. Factors accounting for the relatively low critical temperatures T c in transition metal compounds with light elements are considered and the possible ways of increasing T c are discussed. [ABSTRACT FROM AUTHOR]

A brief review is given on the studies of ferroelectricity in perovskites. Early phenomenological theories of displacement-type ferroelectrics are considered. Two markedly different approaches based on density-functional theory are described. In one approach, the electron density of crystal is determined as a sum of Bloch functions. In the other, it is constructed as a superposition of the electron densities of individual ions. The latter approach gives a microscopic justification for the old phenomenological theories. We show that some phenomena in perovskites, which seemingly are of the order-disorder origin, can be explained by quasi-one-dimensional peculiarities of lattice dynamics. [ABSTRACT FROM AUTHOR]

Background: All organisms living under aerobic atmosphere have powerful mechanisms that confer their macromolecules protection against oxygen reactive species. Microorganisms have developed biomolecule-protecting systems in response to starvation and/or oxidative stress, such as DNA biocrystallization with Dps (DNA-binding protein from starved cells). Dps is a protein that is produced in large amounts when the bacterial cell faces harm, which results in DNA protection. In this work, we evaluated the glycosylation in the Dps extracted from Salmonella enterica serovar Typhimurium. This Dps was purified from the crude extract as an 18-kDa protein, by means of affinity chromatography on an immobilized jacalin column. Results: The N-terminal sequencing of the jacalin-bound protein revealed 100% identity with the Dps of S. enterica serovar Typhimurium. Methyl-alpha-galactopyranoside inhibited the binding of Dps to jacalin in an enzyme-linked lectin assay, suggesting that the carbohydrate recognition domain (CRD) of jacalin is involved in the interaction with Dps. Furthermore, monosaccharide compositional analysis showed that Dps contained mannose, glucose, and an unknown sugar residue. Finally, jacalin-binding Dps was detected in larger amounts during the bacterial earlier growth periods, whereas high detection of total Dps was verified throughout the bacterial growth period. Conclusion: Taken together, these results indicate that Dps undergoes post-translational modifications in the pre- and early stationary phases of bacterial growth. There is also evidence that a small mannose-containing oligosaccharide is linked to this bacterial protein. [ABSTRACT FROM AUTHOR]

Aims: To isolate bacteria capable of cleaving aliphatic carbon–sulfur bonds as potential biological upgrading catalysts for the reduction of molecular weight and viscosity in heavy crude oil. Methods and Results: Thirty-one bacterial strains isolated from enrichment cultures were able to biotransform model compounds representing the aliphatic sulfide bridges found in asphaltenes. Using gas chromatography and mass spectrometry, three types of attack were identified: alkyl chain degradation, allowing use as a carbon source; nonspecific sulfur oxidation; and sulfur-specific oxidation and carbon–sulfur bond cleavage, allowing use as a sulfur source. Di- n-octyl sulfide degradation produced octylthio- and octylsulfonyl-alkanoic acids, consistent with terminal oxidation followed by β-oxidation reactions. Utilization of dibenzyl sulfide or 1,4-dithiane as a sulfur source was regulated by sulfate, indicating a sulfur-specific activity rather than nonspecific oxidation. Finally, several isolates were also able to use dibenzothiophene as a sulfur source, and this was the preferred organic sulfur substrate for one isolate. Conclusions: The use of commercially available alkyl sulfides in enrichment cultures gave isolates that followed a range of metabolic pathways, not just sulfur-specific attack. Significance and Impact of the Study: These results give new insight into biodegradation of organosulfur compounds from petroleum and for biotreatment of such compounds in chemical munitions. [ABSTRACT FROM AUTHOR]

Aim. This paper reports a study examining the direct effects of perceived stress, perceived availability of and satisfaction with social support, and self-efficacy, and examines the intermediary roles of perceived threat (perceived susceptibility x perceived severity), benefits, and barriers on alcohol behaviour, smoking behaviour, physical activity and nutrition behaviour, general safety behaviour and sun-protective behaviour in college students.Background. Health behaviours formed during young adulthood may have a sustaining impact on health across later life. Entering college can be an exciting, yet stressful event for many adolescents and young adults as they face trying to adapt to changes in academic workloads, support networks, and their new environment. Coupled with these changes and new-found responsibilities, they have greater freedom and control over their lifestyles than ever before. However, researchers have shown globally that many college students engage in various risky health behaviours.Method. A cross-sectional sample of 161 college students enrolled in an introductory psychology course completed self-report questionnaires regarding stress; social support; self-efficacy; and components of the Health Belief Model including perceived threat, perceived benefits, perceived barriers; and common health behaviours. Step-wise multiple regression analysis was conducted and significant predictors were retained as modifiers in the path analysis.Findings. Self-efficacy significantly predicted alcohol and smoking behaviour, physical activity and nutrition protective behaviour, general safety protective behaviour and sun-protective behaviour. Under high-perceived threat, self-efficacy was mediated by perceived barriers for binge drinking and moderated by perceived barriers for physical activity and nutrition behaviours. In addition, under high-perceived threat, self-efficacy was moderated by perceived threat for alcohol use at 30 days and 6 months. Under low threat, self-efficacy was mediated by perceived barriers for smoking behaviour and general safety protective behaviours.Conclusions. Future health promotion programmes with college students must use interventions that maximize self-efficacy and ultimately reduce barriers to adopting a healthy lifestyle. [ABSTRACT FROM AUTHOR]

Abinitio calculations of the superconducting properties have been performed for niobium carbide (NbC) at normal pressure and upon a 15 and 30% compression. Factors accounting for the relatively low values of the transition temperature Tc in transition metal carbides are considered and the possible ways of increasing this parameter are discussed. © 2004 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

: This study aimed to investigate the effectiveness of a one-week triple therapy with esomeprazole, clarithromycin and metronidazole for eradication of Helicobacter pylori infection in the absence of antimicrobial resistance. : Patients testing positive for H. pylori susceptible to metronidazole and clarithromycin ( E-test) were randomized to receive a one-week regimen with either esomeprazole 2 × 20 mg or omeprazole 2 × 20 mg in combination with clarithromycin 2 × 250 mg and metronidazole 2 × 400 mg. Follow-up endoscopy with histology and culture and/or rapid urease test was performed 4–8 weeks after the end of treatment. : Eighty patients were randomized. Helicobacter pylori infection was cured in 38/39 patients of the esomeprazole group and 31/33 patients of the omeprazole group (per protocol 97.4% (95% confidence interval [CI], 86.2–99.9), 93.7% (95% CI, 79.2–99.2), P = 0.59); intention-to-treat 90.4% (95% CI: 77.4–97.3), 81.6% (95% CI: 65.7–92.3), respectively. No major side effects occurred. Minor side effects occurred in eight (20%) and six (23%) patients during esomeprazole and omeprazole therapy, respectively. Post-treatment susceptibility testing revealed resistance to both metronidazole and clarithromycin in two of the three patients who failed. : We conclude that esomeprazole, clarithromycin and metronidazole as one-week triple therapy is effective for eradication of H. pylori in the absence of antimicrobial resistance. [ABSTRACT FROM AUTHOR]

The ability of the psychological resistance factors Sense of Coherence (SOC) and dispositional Optimism (LOT-R) to predict physical symptom reporting (PILL), psychological wellbeing (MHI-5) and perceived general health (SF-36®), over and above demographic variables (age, race, gender) and the 'Big Five' personality dimensions (NEO-FFI®) was explored in a sample of 202 undergraduate students. Hierarchical regression analyses identified race, Neuroticism, and Extraversion as significant predictors of physical symptom reporting. Neuroticism, Sense of Coherence and Optimism were identified as significant predictors of psychological wellbeing. Only Sense of Coherence was a significant predictor of perceived general health. Coping was tested as a mediator using structural equation modeling. Avoidance coping, but not approach coping, mediated the relationship between Sense of Coherence and psychological wellbeing and general health. Coping did not mediate the relationship between Neuroticism and/or race and physical symptom reporting. The hypothesis that Sense of Coherence contributes uniquely to perceived health was supported. [ABSTRACT FROM AUTHOR]

Neuronal nicotinic acetylcholine receptors (nAChRs) play a significant role in sympathetic transmission in the superior cervical ganglia (SCG), with most of the signal carried by a nAChR containing an α3 subunit. Work has shown that transection of the postganglionic nerves (axotomy) of the SCG results in a decrease in mRNA transcripts for α3, α5, α7 and β4 and in protein expression of α7 and β4. To evaluate effects of axotomy on α3 protein in the SCG, quantitative immunoblotting was used to demonstrate a dramatic decrease (> 80%) in the levels of this subunit 4 days after axotomy. Similarly, immunocytochemistry showed a marked decline in the number and the intensity of stained neurons for the α3 subunit as well as tyrosine hydroxylase. Ganglia explanted into culture for 4 days also showed a substantial decrease in α3 subunit protein. This decrease was partially prevented by the addition of nerve growth factor (NGF) to the culture medium at the time of explantation. Additionally, this decrease was reversed by the addition of NGF to the culture medium following 4 days in culture in the absence of NGF. These findings suggest that the loss of α3 subunit contributes to the reported decrease in ganglionic synaptic transmission that follows axotomy, and that NGF plays an important role in regulating the expression of α3-containing nAChRs in the SCG. [ABSTRACT FROM AUTHOR]

Animal studies that compare antibiotics have used only a limited number of doses administered at intervals chosen without regard for their pharmacodynamic effects or pharmacokinetic profiles. We compared the relative efficacy and potency of three β-lactams and two aminoglycosides in lung and thigh-infection models in neutropenic mice by defining the maximum attainable antimicrobial effect at 24 h (Emax) and the total dose required to reach 50% of maximum effect (P50) at several dosing intervals. For β-lactams, Emaxs were similar, whereas Psos increased 10- to 50-fold with longer intervals in both models. Aminoglycosides were significantly more bactericidal in the lung than in the thigh, and dosing interval had little impact on Psos in either model. Recognizing the variable impact of dosing interval on efficacy for different classes of antibiotics is mandatory for the proper design and interpretation of comparative trials. [ABSTRACT FROM PUBLISHER]

Current antimicrobial dosing regimens are designed to maintain active drug levels for most of the dosing interval and are based on 40-y-old observations. With use of numerous multiple-dosing regimens in an animal model, this study is the first to successfully minimize the interdependence between pharmacokinetic parameters and thereby determine, by stepwise multivariate regression analysis, that the time that serum levels exceeded the minimum inhibitory concentration (MIC) was the most significant parameter determining efficacy for β-lactams and erythromycin against various pathogens, whereas the log area under the curve was the major parameter for aminoglycosides. Optimal dosing intervals were no greater than the time that serum levels exceeded the MIC plus the duration of the postantibiotic effect. Careful application of these concepts should allow other investigators to use more optimally dosed regimens than those previously used in preclinical trials and to design studies to improve on current dosing regimens for humans. [ABSTRACT FROM PUBLISHER]

A murine thigh-infection model was used to determine the effect of certain host- and drug-related factors on the duration of the in-vivo postantibiotic effect (PAE) observed with aminoglycosides against Gram-negative bacilli. The role of neutrophils (PMNs), pharmacokinetics and variation among species and strains were studied. PAEs were quantitated after a single injection of gentamicin or amikacin. PAEs were several hours longer in normal mice than in neutropenic mice, in mice with renal impairment than in those with normal renal function, and with strains of Klebsiella pneumoniae than with strains of Escherichia coli, Serratia marcescens and Enterobacter cloacae. Among the 15 strains of Enterobacteriaceae studied, the duration of the in-vivo PAE did not correlate with MIC, duration of in-vitro PAE, and extent of in-vivo bactericidal activity. We conclude that prolonged PAEs are consistently observed in vivo with aminoglycosides against Enterobacteriaceae, and that this duration is enhanced in the presence of PMNs and by pharmacokinetic properties simulating those observed in humans. [ABSTRACT FROM AUTHOR]

Lactate dehydrogenase activities were measured along two sinusoidal paths ( 1) between small portal tracts and central veins and ( 2) between regions of adjoining septal branches and central veins in the livers of male Wistar rats, using a Lowry technique. The established profiles of enzyme activity provide further support of functional heterogeneity of liver sinusoids and their abutting hepatocytes related to morphological differences of the sinusoidal bed. Within the hepatocytes a pronounced heterogeneity in enzyme activity was recorded surrounding small portal tracts and central veins. The lowest values of activity were determined in those cells located in close proximity to the vessels, which emphasizes their exceptional morphological and functional position. [ABSTRACT FROM AUTHOR]

Iron doping of InP and GaInAsP(λ[sub g]=1.05 μm) layers grown by metalorganic molecular beam epitaxy was studied using elemental source material in combination with a conventional effusion cell. This study was aimed at the creation of semi-insulating optical waveguides under growth conditions compatible with selective area growth. Secondary ion mass spectroscopy measurements revealed a reproducible and homogeneous incorporation behavior of the iron dopant in the materials investigated. Resistivities in excess of 10[sup 9] Ω cm were obtained for both compositions at medium doping levels. GaInAsP/InP waveguide structures grown at 485 °C—the minimum temperature necessary for selective deposition—exhibited averaged resistivities of 5×10[sup 7] Ω cm in combination with optical losses of 2.5±0.5 dB/cm. © 1998 American Institute of Physics. [ABSTRACT FROM AUTHOR]

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Background & Aim: Esomeprazole-based triple therapy with clarithromycin and amoxicillin has recently been shown to be effective for H. pylori eradication. The aim of this study was to determine the efficacy of a 7-day triple therapy with esomeprazole, clarithromycin and metronidazole for eradication of H. pylori in the absence of antimicrobial resistance. Patients & Methods: Patients infected with H. pylori sensitive to metronidazole and clarithromycin (E-Test) were randomized to one-week triple therapy with either esomeprazole 2 × 20 mg, clarithromycin 2 × 250 mg and metronidazole 2 × 400 mg, (ECM), or omeprazole 2 × 20 mg, clarithromycin 2 × 250 mg and metronidazole 2 × 400 mg (OCM). Control endoscopy with histology and culture and/or rapid urease test was performed 4 to 8 weeks after the end of treatment. Results: 76 patients were randomized. So far, 63 patients returned to control examinations and were analyzed (23 females, 27 peptic ulcer disease, median age 43 years). All 63 patients completed their therapy as scheduled. There were no major side effects leading to discontinuation of treatment. Minor side effects occurred in 8 (23.5%) and 4 (13.8%) patients during ECM and OCM therapy, respectively. So far, 33 of 34 patients of the ECM group (97%) and 27 of 29 patients of the OCM group (93%) were cured of H. pylori infection. Post-treatment antimicrobial susceptibility testing showed resistance to both metronidazole and clarithroymcin in 2 of 3 patients. Conclusion: Our preliminary data suggest a high efficacy of esomeprazole-based triple therapy with clarithromycin and metronidazole for eradication of H. pylori in the absence of antimicrobial resistance. [ABSTRACT FROM AUTHOR]

Background: Luteolin, a plant derived flavonoid, exerts a variety of pharmacological activities and anti-oxidant properties associated with its capacity to scavenge oxygen and nitrogen species. Luteolin also shows potent anti-inflammatory activities by inhibiting nuclear factor kappa B (NFkB) signaling in immune cells. To better understand the immuno-modulatory effects of this important flavonoid, we performed a genome-wide expression analysis in pro-inflammatory challenged microglia treated with luteolin and conducted a phenotypic and functional characterization.Methods: Resting and LPS-activated BV-2 microglia were treated with luteolin in various concentrations and mRNA levels of pro-inflammatory markers were determined. DNA microarray experiments and bioinformatic data mining were performed to capture global transcriptomic changes following luteolin stimulation of microglia. Extensive qRT-PCR analyses were carried out for an independent confirmation of newly identified luteolin-regulated transcripts. The activation state of luteolin-treated microglia was assessed by morphological characterization. Microglia-mediated neurotoxicity was assessed by quantifying secreted nitric oxide levels and apoptosis of 661W photoreceptors cultured in microglia-conditioned medium.Results: Luteolin dose-dependently suppressed pro-inflammatory marker expression in LPS-activated microglia and triggered global changes in the microglial transcriptome with more than 50 differentially expressed transcripts. Pro-inflammatory and pro-apoptotic gene expression was effectively blocked by luteolin. In contrast, mRNA levels of genes related to anti-oxidant metabolism, phagocytic uptake, ramification, and chemotaxis were significantly induced. Luteolin treatment had a major effect on microglial morphology leading to ramification of formerly amoeboid cells associated with the formation of long filopodia. When co-incubated with luteolin, LPS-activated microglia showed strongly reduced NO secretion and significantly decreased neurotoxicity on 661W photoreceptor cultures.Conclusions: Our findings confirm the inhibitory effects of luteolin on pro-inflammatory cytokine expression in microglia. Moreover, our transcriptomic data suggest that this flavonoid is a potent modulator of microglial activation and affects several signaling pathways leading to a unique phenotype with anti-inflammatory, anti-oxidative, and neuroprotective characteristics. With the identification of several novel luteolin-regulated genes, our findings provide a molecular basis to understand the versatile effects of luteolin on microglial homeostasis. The data also suggest that luteolin could be a promising candidate to develop immuno-modulatory and neuroprotective therapies for the treatment of neurodegenerative disorders. [ABSTRACT FROM AUTHOR]