990 research outputs found

    Confirming Bank Liability in Letter of Credit Transactions: Whose Bank Is It Anyway?

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    Context. The abundance of deuterated molecules in a star-forming region is sensitive to the environment in which they are formed. Deuteration fractions, in other words the ratio of a species containing D to its hydrogenated counterpart, therefore provide a powerful tool for studying the physical and chemical evolution of a star-forming system. While local low-mass star-forming regions show very high deuteration ratios, much lower fractions are observed towards Orion and the Galactic centre. Astration of deuterium has been suggested as a possible cause for low deuteration in the Galactic centre. Aims. We derive methanol deuteration fractions at a number of locations towards the high-mass star-forming region NGC 6334I, located at a mean distance of 1.3 kpc, and discuss how these can shed light on the conditions prevailing during its formation. Methods. We use high sensitivity, high spatial and spectral resolution observations obtained with the Atacama Large Millimeter/ submillimeter Array to study transitions of the less abundant, optically thin, methanol-isotopologues: 13CH3OH, CH318OH, CH2DOH and CH3OD, detected towards NGC 6334I. Assuming local thermodynamic equilibrium (LTE) and excitation temperatures of ~120–330 K, we derive column densities for each of the species and use these to infer CH2DOH/CH3OH and CH3OD/CH3OH fractions. Results. We derive column densities in a range of (0.8–8.3) × 1017 cm−2 for 13CH3OH, (0.13–3.4) × 1017 cm−2 for CH318OH, (0.03–1.63) × 1017 cm−2 for CH2DOH and (0.15–5.5) × 1017 cm−2 for CH3OD in a ~1″ beam. Interestingly, the column densities of CH3OD are consistently higher than those of CH2DOH throughout the region by factors of 2–15. We calculate the CH2DOH to CH3OH and CH3OD to CH3OH ratios for each of the sampled locations in NGC 6334I. These values range from 0.03% to 0.34% for CH2DOH and from 0.27% to 1.07% for CH3OD if we use the 13C isotope of methanol as a standard; using the 18 O-methanol as a standard, decreases the ratios by factors of between two and three. Conclusions. All regions studied in this work show CH2DOH/CH3OH as well as CH2DOH/CH3OD values that are considerably lower than those derived towards low-mass star-forming regions and slightly lower than those derived for the high-mass star-forming regions in Orion and the Galactic centre. The low ratios indicate a grain surface temperature during formation ~30 K, for which the efficiency of the formation of deuterated species is significantly reduced. Therefore, astration of deuterium in the Galactic centre cannot be the explanation for its low deuteration ratio but rather the high temperatures characterising the region

    Collaboration: protocol for a systematic review with individual participant data meta-analysis of behavioural interventions for the prevention of early childhood obesity.

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    Introduction Behavioural interventions in early life appear to show some effect in reducing childhood overweight and obesity. However, uncertainty remains regarding their overall effectiveness, and whether effectiveness differs among key subgroups. These evidence gaps have prompted an increase in very early childhood obesity prevention trials worldwide. Combining the individual participant data (IPD) from these trials will enhance statistical power to determine overall effectiveness and enable examination of individual and trial-level subgroups. We present a protocol for a systematic review with IPD meta- analysis to evaluate the effectiveness of obesity prevention interventions commencing antenatally or in the first year after birth, and to explore whether there are differential effects among key subgroups. Methods and analysis Systematic searches of Medline, Embase, Cochrane Central Register of Controlled Trials, Cumulative Index to Nursing and Allied Health Literature (CINAHL), PsycInfo and trial registries for all ongoing and completed randomised controlled trials evaluating behavioural interventions for the prevention of early childhood obesity have been completed up to March 2021 and will be updated annually to include additional trials. Eligible trialists will be asked to share their IPD; if unavailable, aggregate data will be used where possible. An IPD meta-analysis and a nested prospective meta- analysis will be performed using methodologies recommended by the Cochrane Collaboration. The primary outcome will be body mass index z-score at age 24±6 months using WHO Growth Standards, and effect differences will be explored among prespecified individual and trial-level subgroups. Secondary outcomes include other child weight-related measures, infant feeding, dietary intake, physical activity, sedentary behaviours, sleep, parenting measures and adverse events. 73) and Flinders University Social and Behavioural Research Ethics Committee (HREC CIA2133- 1). Results will be Department. eminated via publications, presentations and media releases

    Unpacking the behavioural components and delivery features of early childhood obesity prevention interventions in the TOPCHILD Collaboration: a systematic review and intervention coding protocol.

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    Introduction: Little is known about how early (eg, commencing antenatally or in the first 12 months after birth) obesity prevention interventions seek to change behaviour and which components are or are not effective. This study aims to (1) characterise early obesity prevention interventions in terms of target behaviours, delivery features and behaviour change techniques (BCTs), (2) explore similarities and differences in BCTs used to target behaviours and (3) explore effectiveness of intervention components in preventing childhood obesity. Methods and analysis: Annual comprehensive systematic searches will be performed in Epub Ahead of Print/MEDLINE, Embase, Cochrane (CENTRAL), CINAHL, PsycINFO, as well as clinical trial registries. Eligible randomised controlled trials of behavioural interventions to prevent childhood obesity commencing antenatally or in the first year after birth will be invited to join the Transforming Obesity in CHILDren Collaboration. Standard ontologies will be used to code target behaviours, delivery features and BCTs in both published and unpublished intervention materials provided by trialists. Narrative syntheses will be performed to summarise intervention components and compare applied BCTs by types of target behaviours. Exploratory analyses will be undertaken to assess effectiveness of intervention components. Ethics and dissemination: The study has been approved by The University of Sydney Human Research Ethics Committee (project no. 2020/273) and Flinders University Social and Behavioural Research Ethics Committee (project no. HREC CIA2133-1). The study's findings will be disseminated through peer-reviewed publications, conference presentations and targeted communication with key stakeholders

    Hamiltonian Structures for the Ostrovsky-Vakhnenko Equation

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    We obtain a bi-Hamiltonian formulation for the Ostrovsky-Vakhnenko equation using its higher order symmetry and a new transformation to the Caudrey-Dodd-Gibbon-Sawada-Kotera equation. Central to this derivation is the relation between Hamiltonian structures when dependent and independent variables are transformed.Comment: 13 page

    Efficiency of the dynamical mechanism

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    The most extreme starbursts occur in galaxy mergers, and it is now acknowledged that dynamical triggering has a primary importance in star formation. This triggering is due partly to the enhanced velocity dispersion provided by gravitational instabilities, such as density waves and bars, but mainly to the radial gas flows they drive, allowing large amounts of gas to condense towards nuclear regions in a small time scale. Numerical simulations with several gas phases, taking into account the feedback to regulate star formation, have explored the various processes, using recipes like the Schmidt law, moderated by the gas instability criterion. May be the most fundamental parameter in starbursts is the availability of gas: this sheds light on the amount of external gas accretion in galaxy evolution. The detailed mechanisms governing gas infall in the inner parts of galaxy disks are discussed.Comment: 6 pages, 3 figures, to be published in "Starbursts - From 30 Doradus to Lyman break galaxies", ed. R. de Grijs and R. Gonzalez-Delgad

    Building Capacity in a Rural North Carolina Community to Address Prostate Health Using a Lay Health Advisor Model

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    Background. Prostate cancer is a critical concern for African Americans in North Carolina (NC), and innovative strategies are needed to help rural African American men maximize their prostate health. Engaging the community in research affords opportunities to build capacity for teaching and raising awareness. Approach and Strategies. A community steering committee of academicians, community partners, religious leaders, and other stakeholders modified a curriculum on prostate health and screening to include interactive knowledge- and skill-building activities. This curriculum was then used to train 15 African American lay health advisors, dubbed Prostate Cancer Ambassadors, in a rural NC community. Over the 2-day training, Ambassadors achieved statistically significant improvements in knowledge of prostate health and maintained confidence in teaching. The Ambassadors, in turn, used their personal networks to share their knowledge with over 1,000 individuals in their community. Finally, the Ambassadors became researchers, implementing a prostate health survey in local churches. Discussion and Conclusions. It is feasible to use community engagement models for raising awareness of prostate health in NC African American communities. Mobilizing community coalitions to develop curricula ensures that the curricula meet the communities’ needs, and training lay health advisors to deliver curricula helps secure community buy-in for the information

    Prostate Cancer Ambassadors: Enhancing a Theory-Informed Training Program for Informed Decision-Making

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    BACKGROUND Longer lifespans conferred by antiretroviral therapy result in more time exposed to cancer risk for people living with HIV/AIDS (PLWHA). Given limited diversity in AIDS Malignancy Consortium (AMC) clinical trials, there is need for new approaches to educate PLWHA in order to improve awareness and participation in AMC trials. METHODS With input from a community advisory board, Project ACCRUE (AMC Clinical Trials at Carolina Ramp Up Enrollment) conducted a key informant interview with service providers; online organizational surveys of AMC trial awareness and resource needs; and "lunch and learn" educational sessions, including pre- and post-intervention knowledge assessments. RESULTS Providers indicated that transportation, mistrust of the medical community, and affordability were barriers to trial participation, while printed educational materials could facilitate trial recruitment. Providers indicated that their clients had concerns about participating in trials, but also recognized several benefits of participation including access to medical personnel and treatment, receipt of monetary incentives, and a feeling of satisfaction from helping others. In lunch and learn sessions, use of an audience response system to collect questionnaire data improved scores on knowledge-based items [S(55) = 460; P < .0001] compared to a pencil and paper test [S(20) = 12.5; P = .6541]. LIMITATIONS Generalizability may have been compromised by the small sample size. Long-term recall was not measured, and the short retest interval may have impacted post-intervention assessments. CONCLUSIONS Service providers recognize the benefits of working with researchers to educate patients about HIV-related cancers and participation in clinical trials. Lunch and learn sessions improved knowledge and perceptions about clinical trials for PLWHA

    Prostate Cancer Ambassadors: Process and Outcomes of a Prostate Cancer Informed Decision-Making Training Program

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    African American men bear a higher burden of prostate cancer than Caucasian men, but knowledge about how to make an informed decision about prostate cancer screening is limited. A lay health advisor model was used to train “Prostate Cancer Ambassadors” on prostate cancer risk and symptoms, how to make an informed decision for prostate-specific antigen screening, and how to deliver the information to members of their community. Training consisted of two, 6-hour interactive sessions and was implemented in three predominantly African American communities over an 8-month period between 2013 and 2014. Following training, Ambassadors committed to contacting at least 10 people within 3 months using a toolkit composed of wallet-sized informational cards for distribution, a slide presentation, and a flip chart. Thirty-two Ambassadors were trained, with more than half being females (59%) and half reporting a family history of prostate cancer. Prostate cancer knowledge improved significantly among Ambassadors (p ≀.0001). Self-efficacy improved significantly for performing outreach tasks (p <.0001), and among women in helping a loved one with making an informed decision (p =.005). There was also an improvement in collective efficacy in team members (p =.0003). Twenty-nine of the Ambassadors fulfilled their commitment to reach at least 10 people (average number of contacts per Ambassador was 11). In total, 355 individuals were reached with the prostate cancer information. The Ambassador training program proved successful in training Ambassadors to reach communities about prostate cancer and how to make an informed decision about screening

    Project ACCRUE: Exploring Options to Increase Awareness of AIDS Malignancy Consortium Clinical Trials in North Carolina

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    BACKGROUND Longer lifespans conferred by antiretroviral therapy result in more time exposed to cancer risk for people living with HIV/AIDS (PLWHA). Given limited diversity in AIDS Malignancy Consortium (AMC) clinical trials, there is need for new approaches to educate PLWHA in order to improve awareness and participation in AMC trials. METHODS With input from a community advisory board, Project ACCRUE (AMC Clinical Trials at Carolina Ramp Up Enrollment) conducted a key informant interview with service providers; online organizational surveys of AMC trial awareness and resource needs; and "lunch and learn" educational sessions, including pre- and post-intervention knowledge assessments. RESULTS Providers indicated that transportation, mistrust of the medical community, and affordability were barriers to trial participation, while printed educational materials could facilitate trial recruitment. Providers indicated that their clients had concerns about participating in trials, but also recognized several benefits of participation including access to medical personnel and treatment, receipt of monetary incentives, and a feeling of satisfaction from helping others. In lunch and learn sessions, use of an audience response system to collect questionnaire data improved scores on knowledge-based items [S(55) = 460; P < .0001] compared to a pencil and paper test [S(20) = 12.5; P = .6541].LIMITATIONS Generalizability may have been compromised by the small sample size. Long-term recall was not measured, and the short retest interval may have impacted post-intervention assessments. CONCLUSIONS Service providers recognize the benefits of working with researchers to educate patients about HIV-related cancers and participation in clinical trials. Lunch and learn sessions improved knowledge and perceptions about clinical trials for PLWHA

    Can cartilage loss be detected in knee osteoarthritis (OA) patients with 3–6 months' observation using advanced image analysis of 3T MRI?

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    SummaryPurposePrior investigations of magnetic resonance imaging (MRI) biomarkers of cartilage loss in knee osteoarthritis (OA) suggest that trials of interventions which affect this biomarker with adequate statistical power would require large clinical studies of 1–2 years duration. We hypothesized that smaller, shorter duration, “Proof of Concept” (PoC) studies might be achievable by: (1) selecting a population at high risk of rapid medial tibio-femoral (TF) progression, in conjunction with; (2) high-field MRI (3T), and; (3) using advanced image analysis. The primary outcome was the cartilage thickness in the central medial femur.MethodsMulti-centre, non-randomized, observational cohort study at four sites in the US. Eligible participants were females with knee pain, a body mass index (BMI)≄25kg/m2, symptomatic radiographic evidence of medial TF OA, and varus mal-alignment. The 29 participants had a mean age of 62 years, mean BMI of 36kg/m2, with eight index knees graded as Kellgren–Lawrence (K&L)=2 and 21 as K&L=3. Eligible participants had four MRI scans of one knee: two MRIs (1 week apart) were acquired as a baseline with follow-up MRI at 3 and 6 months. A trained operator, blind to time-point but not subject, manually segmented the cartilage from the Dual Echo Steady State water excitation MR images. Anatomically corresponding regions of interest were identified on each image by using a three-dimensional statistical shape model of the endosteal bone surface, and the cartilage thickness (with areas denuded of cartilage included as having zero thickness – ThCtAB) within each region was calculated. The percentage change from baseline at 3 and 6 months was assessed using a log-scale analysis of variance (ANOVA) model including baseline as a covariate. The primary outcome was the change in cartilage thickness within the aspect of central medial femoral condyle exposed within the meniscal window (w) during articulation, neglecting cartilage edges [nuclear (n)] (nwcMF·ThCtAB), with changes in other regions considered as secondary endpoints.ResultsAnatomical mal-alignment ranged from −1.9° to 6.3°, with mean 0.9°. With one exception, no changes in ThCtAB were detected at the 5% level for any of the regions of interest on the TF joint at 3 or 6 months of follow-up. The change in the primary variable (nwcMF·ThCtAB) from (mean) baseline at 3 months from the log-scale ANOVA model was −2.1% [95% confidence interval (CI) (−4.4%, +0.2%)]. The change over 6 months was 0.0% [95% CI (−2.7%, +2.8%)]. The 95% CI for the change from baseline did not include zero for the cartilage thickness within the meniscal window of the lateral tibia (wLT·ThCtAB) at 6 month follow-up (−1.5%, 95% CI [−2.9, −0.2]), but was not significant at the 5% level after correction for multiple comparisons.ConclusionsThe small inconsistent compartment changes, and the relatively high variabilities in cartilage thickness changes seen over time in this study, provide no additional confidence for a 3- or 6-month PoC study using a patient population selected on the basis of risk for rapid progression with the MRI acquisition and analyses employed
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