987 research outputs found

    Synthesis and structures of polyiodide radical cation salts of donors combining tetrathiafulvalene with multiple thiophene or oligo-thiophene substituents

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    A series of TTF and EDT-TTF derived donors bearing thiophene, bithiophene and terthiophene side chains is described, from which a group of six radical cation salts with polyiodide ions were formed and structurally characterised. Typically, they contain complex networks of pentaiodide or triiodide anions or both, in some cases including further iodine, with networks of eight, ten, twelve or sixteen iodine atoms. Donor monocations form face-to-face pairs, but tetrakis-substituted donors are slipped along their main axis so the donor side chains can wrap around each other

    Chiral molecular conductor with an insulator-metal transition close to room temperature

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    Materials exhibiting both chirality and conductivity do not exist in nature and very few examples have been synthesised. We report here the synthesis of a chiral molecular metal which remains metallic down to at least 4.2K. This material also exhibits room-temperature switching capabilities with a transition upon cooling below 10°C

    Analysis of stellar spectra with 3D and NLTE models

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    Models of radiation transport in stellar atmospheres are the hinge of modern astrophysics. Our knowledge of stars, stellar populations, and galaxies is only as good as the theoretical models, which are used for the interpretation of their observed spectra, photometric magnitudes, and spectral energy distributions. I describe recent advances in the field of stellar atmosphere modelling for late-type stars. Various aspects of radiation transport with 1D hydrostatic, LTE, NLTE, and 3D radiative-hydrodynamical models are briefly reviewed.Comment: 21 pages, accepted for publication as a chapter in "Determination of Atmospheric Parameters of B, A, F and G Type Stars", Springer (2014), eds. E. Niemczura, B. Smalley, W. Pyc

    Young women's use of a microbicide surrogate: The complex influence of relationship characteristics and perceived male partners' evaluations

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    This is the post-print version of the article. The official published version can be found at the link below.Currently in clinical trials, vaginal microbicides are proposed as a female-initiated method of sexually transmitted infection prevention. Much of microbicide acceptability research has been conducted outside of the United States and frequently without consideration of the social interaction between sex partners, ignoring the complex gender and power structures often inherent in young women’s (heterosexual) relationships. Accordingly, the purpose of this study was to build on existing microbicide research by exploring the role of male partners and relationship characteristics on young women’s use of a microbicide surrogate, an inert vaginal moisturizer (VM), in a large city in the United States. Individual semi-structured interviews were conducted with 40 young women (18–23 years old; 85% African American; 47.5% mothers) following use of the VM during coital events for a 4 week period. Overall, the results indicated that relationship dynamics and perceptions of male partners influenced VM evaluation. These two factors suggest that relationship context will need to be considered in the promotion of vaginal microbicides. The findings offer insights into how future acceptability and use of microbicides will be influenced by gendered power dynamics. The results also underscore the importance of incorporating men into microbicide promotion efforts while encouraging a dialogue that focuses attention on power inequities that can exist in heterosexual relationships. Detailed understanding of these issues is essential for successful microbicide acceptability, social marketing, education, and use.This study was funded by a grant from National Institutes of Health (NIHU19AI 31494) as well as research awards to the first author: Friends of the Kinsey Institute Research Grant Award, Indiana University’s School of HPER Graduate Student Grant-in-Aid of Research Award, William L. Yarber Sexual Health Fellowship, and the Indiana University Graduate and Professional Student Organization Research Grant

    Multiple breath washout in bronchiectasis clinical trials: is it feasible?

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    BACKDGROUND: Evaluation of multiple breath washout (MBW) set-up including staff training, certification and central “over-reading” for data quality control is essential to determine the feasibility of MBW in future bronchiectasis studies. AIMS: To assess the outcomes of a MBW training, certification and central over-reading programme. METHODS: MBW training and certification was conducted in European sites collecting lung clearance index (LCI) data in the BronchUK Clinimetrics and/or i-BEST-1 studies. The blended training programme included the use of an eLearning tool and a 1-day face-to-face session. Sites submitted MBW data to trained central over-readers who determined validity and quality. RESULTS: Thirteen training days were delivered to 56 participants from 22 sites. Of 22 sites, 18 (82%) were MBW naïve. Participant knowledge and confidence increased significantly (p<0.001). By the end of the study recruitment, 15 of 22 sites (68%) had completed certification with a mean (range) time since training of 6.2 (3–14) months. In the BronchUK Clinimetrics study, 468 of 589 (79%) tests met the quality criteria following central over-reading, compared with 137 of 236 (58%) tests in the i-BEST-1 study. CONCLUSIONS: LCI is feasible in a bronchiectasis multicentre clinical trial setting; however, consideration of site experience in terms of training as well as assessment of skill drift and the need for re-training may be important to reduce time to certification and optimise data quality. Longer times to certification, a higher percentage of naïve sites and patients with worse lung function may have contributed to the lower success rate in the i-BEST-1 study

    Practice belief scales among private general dental practitioners

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    The document attached has been archived with permission from the Australian Dental Association (8th Jan 2008). An external link to the publisher’s copy is included.Background: Practice beliefs have been related to service rate variation. The aims of this study were to replicate practice belief scales in Australia and investigate associations with dentist and practice characteristics and services. Method: A random sample of Australian dentists completed mailed questionnaires (response rate 60.3 per cent). Results: Private general practitioners (n=345) provided service data from a typical day. Eight practice belief items were recorded on a five-point Likert scale, yielding four factor-based scales. Approximately 85 per cent of responses were on the agreement side of the midpoint for the scales of Information giving and Patient influence, 45 per cent for Preventive orientation and approximately 10 per cent for Controlling active disease rather than developing better preventive advice. Capital city dentists had higher agreement with the Preventive orientation scale, while males and older dentists showed less disagreement with the Controlling active disease item (Mann-Whitney, Kruskal-Wallis P<0.05). Those agreeing with the scales (that is scores ≤ the median) showed (Poisson regression P<0.05): a higher rate of crown and bridge, a rate ratio (RR) of 1.31, but lower rates of extraction (RR=0.76) and prosthodontic services (RR=0.64) for the Information giving scale; a higher rate of restorative (RR=1.22) and total services per visit (RR=1.06) for the Preventive orientation scale; a higher rate of preventive services (RR=1.14), but a lower rate of crown and bridge services (0.78) for the Patient influence scale; and higher rates of crown and bridge (RR=1.40) and prosthodontic (RR=1.59) but lower rates of periodontic (RR=0.60) and extraction services (RR=0.62) for the Controlling active disease item. Conclusions: These findings confirm the factor structure of practice beliefs and demonstrate small to moderate associations with variation in service rates.DS Brennan and AJ Spence

    Unusual Regulation of a Leaderless Operon Involved in the Catabolism of Dimethylsulfoniopropionate in Rhodobacter sphaeroides

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    Rhodobacter sphaeroides strain 2.4.1 is a widely studied bacterium that has recently been shown to cleave the abundant marine anti-stress molecule dimethylsulfoniopropionate (DMSP) into acrylate plus gaseous dimethyl sulfide. It does so by using a lyase encoded by dddL, the promoter-distal gene of a three-gene operon, acuR-acuI-dddL. Transcription of the operon was enhanced when cells were pre-grown with the substrate DMSP, but this induction is indirect, and requires the conversion of DMSP to the product acrylate, the bona fide co-inducer. This regulation is mediated by the product of the promoter-proximal gene acuR, a transcriptional regulator in the TetR family. AcuR represses the operon in the absence of acrylate, but this is relieved by the presence of the co-inducer. Another unusual regulatory feature is that the acuR-acuI-dddL mRNA transcript is leaderless, such that acuR lacks a Shine-Dalgarno ribosomal binding site and 5′-UTR, and is translated at a lower level compared to the downstream genes. This regulatory unit may be quite widespread in bacteria, since several other taxonomically diverse lineages have adjacent acuR-like and acuI-like genes; these operons also have no 5′ leader sequences or ribosomal binding sites and their predicted cis-acting regulatory sequences resemble those of R. sphaeroides acuR-acuI-dddL

    A qualitative study of health care professionals' views and experiences of paediatric advance care planning

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    Background Good end-of-life care planning is vital to ensure optimal care is provided for patients and their families. Two key factors are open and honest advance care planning conversations between the patient (where possible), family, and health care professionals, focusing on exploring what their future wishes are; and the development of an advance care plan document. However, in paediatric and neonatal settings, there has been little research to demonstrate how advance care planning conversations take place. This study explored health care professionals’ views and experiences of paediatric advance care planning in hospitals, community settings and hospices. MethodsA qualitative methodology was employed using purposive sampling of health care professionals involved in the end-of-life care for children aged 0–18 years known to the hospital palliative care team, and had died at least three months before, but less than 18 months prior to the study. Ethics committee approval was obtained for the study. Located in the North of England, the study involved three hospitals, a children’s hospice, and community services. Data were collected using semi-structured, digitally recorded, telephone interviews. All interviews were transcribed verbatim and subjected to thematic analysis. ResultsTwenty-one health care professionals participated, including generalist paediatric staff as well as specialist palliative care staff.Two themes were generated from the study: The timing of planning conversations, including waiting for the relationship with the family to form; the introduction of parallel planning; avoiding a crisis situation. Secondly, supporting effective conversations around advance care planning, including where to have the conversation; introducing the conversation; and how to approach the topic encompassing the value of advance care planning and documentation for families. Conclusion The timing of when to start the advance care planning conversations remains an issue for health care professionals. The value of doing it in stages and considering the environment where the conversations are held was noted. Timely planning was seen as vital to avoid difficult conversations at a crisis point and for co-ordination of care. Good advance care planning is to provide the best person-centred care for the child and experience for the family

    Cyber Stalking, Cyber Harassment and Adult Mental Health: A Systematic Review

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    As Internet use increases, there is a growing risk of online harms, including cyber stalking and cyber harassment. However, there has been limited research investigating the impact of such online harms upon adults’ well-being. This paper engages in a systematic literature review concerning the mental health impact of online stalking and harassment for adult victims to further understand their experiences and the effects these have on their lives. Our research utilised the PRISMA technique to review papers published in eight online databases. A total of 1,204 articles were extracted, and ultimately 43 articles analysed. Forty-two of the reviewed articles reported that victims of cyber stalking and/or harassment experienced a multitude of harmful and detrimental consequences for their mental health including depression, anxiety, suicidal ideation and panic attacks. Victims recounted the lack of support they received from the criminal justice system, and their subsequent distrust of technology post abuse. Only one study found no relationship between cyber abuse victimisation and the well-being dimensions they examined. Our research highlights the need to devise practical solutions to tackle and minimise this victimisation. Furthermore, it underlines the necessity for adult education concerning safer technology use, as well as for researchers to be transparent regarding the platforms that victims have been abused on so we can better infer where and how exactly individuals need support to interact safely online
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