The effect of an isothermal atmosphere on the propagation of three-dimensional waves in a thermally stratified accretion disk

We extend our analysis of the three-dimensional response of a vertically polytropic disk to tidal forcing at Lindblad resonances by including the effects of a disk atmosphere. The atmosphere is modeled as an isothermal layer that joins smoothly on to an underlying polytropic layer. The launched wave progressively enters the atmosphere as it propagates away from the resonance. The wave never propagates vertically, however, and the wave energy rises to a (finite) characteristic height in the atmosphere. The increase of wave amplitude associated with this process of wave channeling is reduced by the effect of the atmosphere. For waves of large azimuthal mode number m generated by giant planets embedded in a disk, the increase in wave amplitude is still substantial enough to be likely to dissipate the wave energy by shocks for even modest optical depths (tau greater than about 10) over a radial distance of a few times the disk thickness. For low-m waves generated in circumstellar disks in binary stars, the effects of wave channeling are less important and the level of wave nonlinearity increases by less than a factor of 10 in going from the disk edge to the disk center. For circumbinary disks, the effects of wave channeling remain important, even for modest values of optical depth.Comment: 11 pages, 4 figures, submitted to the Astrophysical Journa

Predicting facebook users online privacy protection: Risk, trust, norm focus theory, and the theory of planned behavior

Journal ArticleThis is an Accepted Manuscript of an article published by Taylor & Francis in The Journal of Social Psychology on 21 April 2014, available online: http://wwww.tandfonline.com/10.1080/00224545.2014.914881The present research adopts an extended theory of the planned behavior model that included descriptive norms, risk, and trust to investigate online privacy protection in Facebook users. Facebook users (N = 119) completed a questionnaire assessing their attitude, subjective injunctive norm, subjective descriptive norm, perceived behavioral control, implicit perceived risk, trust of other Facebook users, and intentions toward protecting their privacy online. Behavior was measured indirectly 2 weeks after the study. The data show partial support for the theory of planned behavior and strong support for the independence of subjective injunctive and descriptive norms. Risk also uniquely predicted intentions over and above the theory of planned behavior, but there were no unique effects of trust on intentions, nor of risk or trust on behavior. Implications are discussed. © Copyright © Taylor & Francis Group, LLC

Disruption of Escherichia coli Nissle 1917 K5 Capsule Biosynthesis, through Loss of Distinct kfi genes, Modulates Interaction with Intestinal Epithelial Cells and Impact on Cell Health

Escherichia coli Nissle 1917 (EcN) is among the best characterised probiotics, with a proven clinical impact in a range of conditions. Despite this, the mechanisms underlying these "probiotic effects" are not clearly defined. Here we applied random transposon mutagenesis to identify genes relevant to the interaction of EcN with intestinal epithelial cells. This demonstrated mutants disrupted in the kfiB gene, of the K5 capsule biosynthesis cluster, to be significantly enhanced in attachment to Caco-2 cells. However, this phenotype was distinct from that previously reported for EcN K5 deficient mutants (kfiC null mutants), prompting us to explore further the role of kfiB in EcN:Caco-2 interaction. Isogenic mutants with deletions in kfiB (EcNΔkfiB), or the more extensively characterised K5 capsule biosynthesis gene kfiC (EcNΔkfiC), were both shown to be capsule deficient, but displayed divergent phenotypes with regard to impact on Caco-2 cells. Compared with EcNΔkfiC and the EcN wild-type, EcNΔkfiB exhibited significantly greater attachment to Caco-2 cells, as well as apoptotic and cytotoxic effects. In contrast, EcNΔkfiC was comparable to the wild-type in these assays, but was shown to induce significantly greater COX-2 expression in Caco-2 cells. Distinct differences were also apparent in the pervading cell morphology and cellular aggregation between mutants. Overall, these observations reinforce the importance of the EcN K5 capsule in host-EcN interactions, but demonstrate that loss of distinct genes in the K5 pathway can modulate the impact of EcN on epithelial cell health

Assessment of low-dose cisplatin as a model of nausea and emesis in beagle dogs, potential for repeated administration

Cisplatin is a highly emetogenic cancer chemotherapy agent, which is often used to induce nausea and emesis in animal models. The cytotoxic properties of cisplatin also cause adverse events that negatively impact on animal welfare preventing repeated administration of cisplatin. In this study, we assessed whether a low (subclinical) dose of cisplatin could be utilized as a model of nausea and emesis in the dog while decreasing the severity of adverse events to allow repeated administration. The emetic, nausea-like behavior and potential biomarker response to both the clinical dose (70 mg/m2) and low dose (15 mg/m2) of cisplatin was assessed. Plasma creatinine concentrations and granulocyte counts were used to assess adverse effects on the kidneys and bone marrow, respectively. Nausea-like behavior and emesis was induced by both doses of cisplatin, but the latency to onset was greater in the low-dose group. No significant change in plasma creatinine was detected for either dose groups. Granulocytes were significantly reduced compared with baseline (P = 0.000) following the clinical, but not the low-dose cisplatin group. Tolerability of repeated administration was assessed with 4 administrations of an 18 mg/m2 dose cisplatin. Plasma creatinine did not change significantly. Cumulative effects on the granulocytes occurred, they were significantly decreased (P = 0.03) from baseline at 3 weeks following cisplatin for the 4th administration only. Our results suggest that subclinical doses (15 and 18 mg/m2) of cisplatin induce nausea-like behavior and emesis but have reduced adverse effects compared with the clinical dose allowing for repeated administration in crossover studies

Disappearance of Transverse Flow in Central Collisions for Heavier Nuclei

For the first time, mass dependence of balance energy only for heavier systems has been studied. Our results are in excellent agreement with the data which allow us to predict the balance energy of U+U, for the first time, around 37-39 MeV/nucleon. Also our results indicate a hard equation of state along with nucleon-nucleon cross-section around 40 mb.Comment: 4 pages, 3 figures, submitted to Phys. Rev. Let

The copy number variant involving part of the \u3b17 nicotinic receptor gene contains a polymorphic inversion.

The \u3b17 nicotinic acetylcholine receptor gene (CHRNA7) is located at 15q13\u2013q14 in a region that is strongly linked to the P50 sensory gating deficit, an endophenotype of schizophrenia and bipolar disorder. Part of the gene is a copy number variant, due to a duplication of exons 5\u201310 and 3\u2032 sequence in CHRFAM7A, which is present in many but not all humans. Maps of this region show that the two genes are in opposite orientation in the individual mainly represented in the public access human DNA sequence database (Build 36), suggesting that an inversion had occurred since the duplication. We have used fluorescent in situ hybridization to investigate this putative inversion. Analysis of interphase chromosomes in 12 individuals confirms the occurrence of an inversion and indicates that CHRFAM7A exists in both orientations with similar frequency. We showed that the 2\u2009bp deletion polymorphism in exon 6 of CHRFAM7A is in strong linkage disequilibrium with the inversion polymorphism (r2=0.82, CI 0.53\u20131.00, P=0.00003), which can therefore be used as a surrogate marker. Previous associations of endophenotypes of schizophrenia with the 2\u2009bp deletion might therefore be due to the orientation of the duplicon containing CHRFAM7A

A single nucleotide polymorphism in the Bax gene promoter affects transcription and influences retinal ganglion cell death

Pro-apoptotic Bax is essential for RGC (retinal ganglion cell) death. Gene dosage experiments in mice, yielding a single wild-type Bax allele, indicated that genetic background was able to influence the cell death phenotype. DBA/2JBax+/− mice exhibited complete resistance to nerve damage after 2 weeks (similar to Bax−/− mice), but 129B6Bax+/− mice exhibited significant cell loss (similar to wild-type mice). The different cell death phenotype was associated with the level of Bax expression, where 129B6 neurons had twice the level of endogenous Bax mRNA and protein as DBA/2J neurons. Sequence analysis of the Bax promoters between these strains revealed a single nucleotide polymorphism (T129B6 to CDBA/2J) at position −515. A 1.5- to 2.5-fold increase in transcriptional activity was observed from the 129B6 promoter in transient transfection assays in a variety of cell types, including RGC5 cells derived from rat RGCs. Since this polymorphism occurred in a p53 half-site, we investigated the requirement of p53 for the differential transcriptional activity. Differential transcriptional activity from either 129B6 or DBA/2J Bax promoters were unaffected in p53−/− cells, and addition of exogenous p53 had no further effect on this difference, thus a role for p53 was excluded. Competitive electrophoretic mobility-shift assays identified two DNA–protein complexes that interacted with the polymorphic region. Those forming Complex 1 bound with higher affinity to the 129B6 polymorphic site, suggesting that these proteins probably comprised a transcriptional activator complex. These studies implicated quantitative expression of the Bax gene as playing a possible role in neuronal susceptibility to damaging stimuli

Fertility Desire and Intention of People Living with HIV/AIDS in Tanzania: A call for Restructuring Care and Treatment Services.

Scaling up of antiretroviral therapy (ART) is currently underway in sub-Saharan Africa including, Tanzania, increasing survival of people living with HIV/AIDS (PLWHA). Programmes pay little attention to PLWHA's reproductive health needs. Information on fertility desire and intention would assist in the integration of sexual and reproductive health in routine care and treatment clinics. A cross-sectional study of all PLWHA aged 15--49 residing in Kahe ward in rural Kilimanjaro Tanzania was conducted. Participants were recruited from the community and a local counselling centre located in the ward. Data on socio-demographic, medical and reproductive characteristics were collected through face-to-face interviews. Data were entered and analysed using STATA statistical software. A total of 410 PLWHA with a mean age of 34.2 and constituting 264 (64.4%) females participated. Fifty-one per cent reported to be married/cohabiting, 73.9% lived with their partners and 60.5% were sexually active. The rate of unprotected sex was 69.0% with 12.5% of women reporting to be pregnant at the time of the survey. Further biological children were desired by 37.1% of the participants and lifetime fertility intention was 2.4 children. Increased fertility desire was associated with living and having sex with a partner, HIV disclosure, good perceived health status and CD4 count >=200 cells for both sexes. Reduced desire was associated with havingmore than 2 children among females, divorce or separation, and having a child with the current partner among both males and females. Fertility desire and intention of PLWHA was substantially high though lower than that of the general population in Tanzania. Practice of unprotected sexual intercourse with higher pregnancy rate was observed. Fertility desire was determined by individual perceived health and socio-family related factors. With increasing ART coverage and subsequent improved quality of life of PLWHA, these findings underscore the importance of integrating reproductive health services in the routine care and treatment of HIV/AIDS worldwide. The results also highlight a group of PLWHA with potentially high desire for children who need to be targeted during care

The feasibility of using pedometers and brief advice to increase activity in sedentary older women:a pilot study

Background: People over the age of 70 carry the greatest burden of chronic disease, disability and health care use. Participation in physical activity is crucial for health, and walking accounts for much of the physical activity undertaken by sedentary individuals. Pedometers are a useful motivational tool to encourage increased walking and they are cheap and easy to use. The aim of this pilot study was to evaluate the feasibility of the use of pedometers plus a theory-based intervention to assist sedentary older women to accumulate increasing amounts of physical activity, mainly through walking. Methods: Female participants over the age of 70 were recruited from primary care and randomised to receive either pedometer plus a theory-based intervention or a theory-based intervention alone. The theory-based intervention consisted of motivational techniques, goal-setting, barrier identification and self-monitoring with pedometers and daily diaries. The pedometer group were further randomised to one of three target groups: a 10%, 15% or 20% monthly increase in step count to assess the achievability and acceptability of a range of targets. The primary outcome was change in daily activity levels measured by accelerometry. Secondary outcome measures were lower limb function, health related quality of life, anxiety and depression. Results: 54 participants were recruited into the study, with an average age of 76. There were 9 drop outs, 45 completing the study. All participants in the pedometer group found the pedometers easy to use and there was good compliance with diary keeping (96% in the pedometer group and 83% in the theory-based intervention alone group). There was a strong correlation (0.78) between accelerometry and pedometer step counts i.e. indicating that walking was the main physical activity amongst participants. There was a greater increase in activity (accelerometry) amongst those in the 20% target pedometer group compared to the other groups, although not reaching statistical significance (p = 0.192). Conclusion: We have demonstrated that it is feasible to use pedometers and provide theory-based advice to community dwelling sedentary older women to increase physical activity levels and a larger study is planned to investigate this further.Publisher PDFPeer reviewe

How much do health care providers value a community-based asthma care program? – a survey to collect their opinions on the utilities of and barriers to its uptake

<p>Abstract</p> <p>Background</p> <p>A comprehensive asthma care program (ACP) based on Canadian Asthma Consensus Guidelines was implemented in 8 primary care sites in Ontario, Canada. A survey was distributed to health care providers' (HCPs) to collect their opinions on the utilities of and barriers to the uptake of the ACP.</p> <p>Methods</p> <p>A 39-item self-administered survey was mailed to 184 HCPs and support staff involved in delivering the ACP at the end of implementation. The items were presented in mixed formats with most items requiring responses on a five-point Likert scale. Distributions of responses were analyzed and compared across types of HCPs and sites.</p> <p>Results</p> <p>Of the 184 surveys distributed, 108 (59%) were returned, and of that, 83 were completed by HCPs who had clinical contact with the patients. Overall, 95% of the HCPs considered the ACP useful for improving asthma care management. Most HCPs favored using the asthma care map (72%), believed it decreased uncertainties and variations in patient management (91%), and considered it a convenient and reliable source of information (86%). The most commonly reported barrier was time required to complete the asthma care map. Over half of the HCPs reported challenges to using spirometry, while almost 40% identified barriers to using the asthma action plan.</p> <p>Conclusion</p> <p>Contrary to the notion that physicians believe that guidelines foster cookbook medicine, our study showed that HCPs believed that the ACP offered an effective and reliable approach for enhancing asthma care and management in primary care.</p