A transit timing analysis of seven RISE light curves of the exoplanet system HAT-P-3

We present seven light curves of the exoplanet system HAT-P-3, taken as part of a transit timing programme using the rapid imager to search for exoplanets instrument on the Liverpool Telescope. The light curves are analysed using a Markov chain Monte Carlo algorithm to update the parameters of the system. The inclination is found to be i= 86.75+0.22−0.21 °, the planet-star radius ratio to be Rp/R★= 0.1098+0.0010−0.0012 and the stellar radius to be R★= 0.834+0.018−0.026 R⊙, consistent with previous results but with a significant improvement in the precision. Central transit times and uncertainties for each light curve are also determined, and a residual permutation algorithm is used as an independent check on the errors. The transit times are found to be consistent with a linear ephemeris, and a new ephemeris is calculated as Tc(0) = 245 4856.701 18 ± 0.000 18 HJD and P= 2.899 738 ± 0.000 007 d. Model timing residuals are fitted to the measured timing residuals to place upper mass limits for a hypothetical perturbing planet as a function of the period ratio. These show that we have probed for planets with masses as low as 0.33 and 1.81 M⊕ in the interior and exterior 2:1 resonances, respectively, assuming the planets are initially in circular orbits

The role of single nucleotide polymorphisms in breast cancer metastasis

Our understanding of many aspects of cancer biology has been advanced through the use of modern genetics. These studies have already shown that germ line polymorphisms play a significant role in disease initiation and response to therapy. However, what is less well studied is the role of germ line polymorphisms in cancer progression. Studies in rodents indicate that differential susceptibility to cancer metastasis can be heritable; thus, the search for the genes that control cancer metastasis is underway. Although some provocative studies suggest potential candidates for metastasis regulating genes, the conclusive identification of a specific inherited genetic variant that alters metastatic potential awaits further studies

The transcriptional repressor protein NsrR senses nitric oxide directly via a [2Fe-2S] cluster

The regulatory protein NsrR, a member of the Rrf2 family of transcription repressors, is specifically dedicated to sensing nitric oxide (NO) in a variety of pathogenic and non-pathogenic bacteria. It has been proposed that NO directly modulates NsrR activity by interacting with a predicted [Fe-S] cluster in the NsrR protein, but no experimental evidence has been published to support this hypothesis. Here we report the purification of NsrR from the obligate aerobe Streptomyces coelicolor. We demonstrate using UV-visible, near UV CD and EPR spectroscopy that the protein contains an NO-sensitive [2Fe-2S] cluster when purified from E. coli. Upon exposure of NsrR to NO, the cluster is nitrosylated, which results in the loss of DNA binding activity as detected by bandshift assays. Removal of the [2Fe-2S] cluster to generate apo-NsrR also resulted in loss of DNA binding activity. This is the first demonstration that NsrR contains an NO-sensitive [2Fe-2S] cluster that is required for DNA binding activity

Identifying component modules

A computer-based system for modelling component dependencies and identifying component modules is presented. A variation of the Dependency Structure Matrix (DSM) representation was used to model component dependencies. The system utilises a two-stage approach towards facilitating the identification of a hierarchical modular structure. The first stage calculates a value for a clustering criterion that may be used to group component dependencies together. A Genetic Algorithm is described to optimise the order of the components within the DSM with the focus of minimising the value of the clustering criterion to identify the most significant component groupings (modules) within the product structure. The second stage utilises a 'Module Strength Indicator' (MSI) function to determine a value representative of the degree of modularity of the component groupings. The application of this function to the DSM produces a 'Module Structure Matrix' (MSM) depicting the relative modularity of available component groupings within it. The approach enabled the identification of hierarchical modularity in the product structure without the requirement for any additional domain specific knowledge within the system. The system supports design by providing mechanisms to explicitly represent and utilise component and dependency knowledge to facilitate the nontrivial task of determining near-optimal component modules and representing product modularity

Understanding the decomposition reaction mechanism of chrysanthemic acid: a computational study

<p>Abstract</p> <p>Background</p> <p>Chrysanthemic acid (<b>CHA</b>) is a major product from the photodecomposition of pyrethrin which is an important class of pesticide compounds.</p> <p>In the following paper, Hybrid density functional theory (DFT) calculations of the potential energy surface (PES) for three possible channels decomposition of chrysanthemic acid <b>(</b>cis-trans isomerization, rearrangement and fragmentation) have been carried at the B3LYP/6-311+G** level of theory. DFT was employed to optimize the geometry parameters of the reactants, transition states, intermediates and products based on detailed potential energy surfaces (PES).</p> <p>Results</p> <p>Our results suggest that all three pathways of <b>CHA </b>are endothermic. DFT calculations revealed that the activation barriers for cis-trans isomerization are low, leading to a thermodynamically favorable process than other two pathways. We also investigated the solvent effect on the PES using the polarizable continuum model (PCM). In addition, time-dependent density functional theory (TDDFT) calculations showed that these reactions occur in the ground state rather than in an excited state.</p> <p>Conclusion</p> <p>The rearrangement process seems to be more favorable than the decomposition of <b>CHA </b>to carbene formation. The solvent effect calculations indicated no changes in the shape of the PES with three continua (water, ethanol and cyclohexane), although the solvents tend to stabilize all of the species.</p

Social Stigma and Knowledge of Tuberculosis and HIV among Patients with Both Diseases in Thailand

INTRODUCTION: Disease-related stigma and knowledge are believed to be associated with patients' willingness to seek treatment and adherence to treatment. HIV-associated tuberculosis (TB) presents unique challenges, because TB and HIV are both medically complex and stigmatizing diseases. In Thailand, we assessed knowledge and beliefs about these diseases among HIV-infected TB patients. METHODS: We prospectively interviewed and examined HIV-infected TB patients from three provinces and one national referral hospital in Thailand from 2005-2006. At the beginning of TB treatment, we asked patients standardized questions about TB stigma, TB knowledge, and HIV knowledge. Responses were grouped into scores; scores equal to or greater than the median score of study population were considered high. Multiple logistic regression analysis was used to identify factors associated with scores. RESULTS: Of 769 patients enrolled, 500 (65%) reported high TB stigma, 177 (23%) low TB knowledge, and 379 (49%) low HIV knowledge. Patients reporting high TB stigma were more likely to have taken antibiotics before TB treatment, to have first visited a traditional healer or private provider, to not know that monogamy can reduce the risk of acquiring HIV infection, and to have been hospitalized at enrollment. Patients with low TB knowledge were more likely to have severe TB disease, to be hospitalized at enrollment, to be treated at the national infectious diseases referral hospital, and to have low HIV knowledge. Patients with low HIV knowledge were more likely to know a TB patient and to have low TB knowledge. DISCUSSION: We found that stigma and low disease-specific knowledge were common among HIV-infected TB patients and associated with similar factors. Further research is needed to determine whether reducing stigma and increasing TB and HIV knowledge among the general community and patients reduces diagnostic delay and improves patient outcomes

Effects of Attractiveness and Social Status on Dating Desire in Heterosexual Adolescents: An Experimental Study

The present study examined to what extent adolescent dating desire is based on attractiveness and social status of a potential short-term partner. Further, we tested whether self-perceived mate value moderated the relationship between dating desire and attractiveness of a potential partner. Data were used from a sample of 1,913 adolescents aged 13–18. Participants rated the importance of various characteristics of a potential partner and also participated in an experimental vignette study in which dating desire was measured with either low or high attractive potential partners having either a high or low social status. The results showed that boys rated attractiveness as more important than girls, while social status was rated as relatively unimportant by both sexes. In addition, in the experimental vignette study, it was found that attractiveness was the primary factor for boys’ dating desire. Only when a potential partner was attractive, social status became important for boys’ dating desire. For girls, on the other hand, it appeared that both attractiveness and social status of a potential partner were important for their dating desire. Finally, boys and girls who perceived themselves as having a high mate value showed more dating desire toward an attractive potential partner compared to adolescents who perceived themselves as having a low mate value. The present results extend previous research by showing that attractiveness of a potential partner is important to both adolescent boys and girls, but social status does not strongly affect dating desire during this particular age period

The Tumor Suppressor Gene, RASSF1A, Is Essential for Protection against Inflammation -Induced Injury

10.1371/journal.pone.0075483PLoS ONE810-POLN

Understanding the role of hospice pharmacists: a qualitative study

Background Pharmacists are important members of multidisciplinary teams but, despite surveys of provision, the role of the hospice pharmacist is not well described. Objective To explore the role of the hospice pharmacist and identify barriers and facilitators to the role. Setting Hospices offering in-patient services caring for adults towards the end of life in one geographical area of northern England. Method Pharmacists providing services to hospices were invited to take part in qualitative semi-structured interviews asking about experience, patient contact, team working and barriers and facilitators to the role. These were recorded verbatim and data were analysed thematically using framework analysis. Main outcome measure The hospice pharmacist’s perceptions of their role and barriers and facilitators to it. Results Fifteen pharmacists took part. Two themes and ten subthemes were identified focused on tasks and communication. Practise was varied and time limited the quantity and depth of services carried out but was often spent navigating complex drug supply routes. Participants found methods of communication suited to the hours they spent in the hospice although communication of data was a barrier to effective clinical service provision. Participants identified the need for appropriate training and standards of practice for hospice pharmacists would enable better use of their skills. Conclusion Barriers to the role of hospice pharmacist include time, access to role specific training, access to clinical information and complex medicines supply chains. The role would benefit from definition to ensure that hospices are able to use hospice pharmacists to their greatest potential