8,399 research outputs found

    Description of the proton and neutron radiative capture reactions in the Gamow shell model

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    We formulate the Gamow shell model (GSM) in coupled-channel (CC) representation for the description of proton/neutron radiative capture reactions and present the first application of this new formalism for the calculation of cross-sections in mirror reactions 7Be(p,gamma)8B and 7Li(n,gamma)8Li. The GSM-CC formalism is applied to a translationally-invariant Hamiltonian with an effective finite-range two-body interaction. Reactions channels are built by GSM wave functions for the ground state 3/2- and the first excited state 1/2- of 7Be/7Li and the proton/neutron wave function expanded in different partial waves

    Gamow shell model description of radiative capture reactions 6^6Li(p,γ)(p,\gamma)7^7Be and 6^6Li(n,γ)(n,\gamma)7^7Li

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    According to standard stellar evolution, lithium abundance is believed to be a useful indicator of the stellar age. However, many evolved stars like red giants show huge fluctuations around expected theoretical abundances that are not yet fully understood. The better knowledge of nuclear reactions that contribute to the creation and destruction of lithium can help to solve this puzzle. In this work we apply the Gamow shell model (GSM) formulated in the coupled-channel representation (GSM-CC) to investigate the mirror radiative capture reactions 6^6Li(p,γ)(p,\gamma)7^7Be and 6^6Li(n,γ)(n,\gamma)7^7Li. The cross-sections are calculated using a translationally invariant Hamiltonian with the finite-range interaction which is adjusted to reproduce spectra, binding energies and one-nucleon separation energies in 67^{6-7}Li, 7^7Be. All relevant E1E1, M1M1, and E2E2 transitions from the initial continuum states to the final bound states J=3/21J={3/2}_1^- and J=1/2J={1/2}^- of 7^7Li and 7^7Be are included. We demonstrate that the ss-wave radiative capture of proton (neutron) to the first excited state Jπ=1/21+J^{\pi}=1/2_1^+ of 7^7Be (7^7Li) is crucial and increases the total astrophysical SS-factor by about 40 \%.Comment: arXiv admin note: text overlap with arXiv:1502.0163

    Cytogenetic characterization of Taphronota thaelephora Stal. 1873. (Orthoptera: Pyrgomorphidae) from Cameroon. II. Description of mitotic chromosomes

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    Taphronota thaelephora Stal. 1873 is generating a lot of interest for biological and cytogenetic studies because it has demonstrated the potential for a future veritable pest in Cameroon. The lack of previouslyestablished karyotype for the species has necessitated this study. Testes from five adult individuals collected from Balepa - Mbouda in the West Region of Cameroon and treated with 1% colchicine were analyzed usingthe Lactic-Propionic Orcein squash technique. Mitotic metaphase chromosomes were measured directly from the microscope and pictures taken with the help of the Lietz photomicroscope. Pictures were processed with the Microsoft Office Picture Manager. The species revealed the standard Pyrgomorphidae karyotype of 2n‰= 19 acrocentric chromosomes. Mean length of the chromosomes ranged from 8.10}1.7 to 3.75}0.0 ƒÊm. Analysis of Relative Chromosome Lengths (RCL) revealed three distinct size groups of long, medium and short. The karyotype of T. thaelephora was made up of 2 pairs of long chromosomes (2LL) and the X-chromosome, 6 pairs of medium chromosomes (6MM) and 1 pair of short chromosomes (1SS). The mean lengths of the long, medium and short sized chromosomes were 7.2 ƒÊm, 4.8 ƒÊm and 3.51 ƒÊm respectively. The X-chromosome was the shortest of the large chromosomes with a mean length of 6.75 ƒÊm

    The association between seeking financial compensation and injury recovery following motor vehicle related orthopaedic trauma

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    © 2016 The Author(s). Background: Motor vehicle related moderate-severe orthopaedic trauma has a major impact on the burden of injury. In Australia, all states and territories provide access to financial compensation following injury in a motor vehicle crash. The aim of this study was to investigate the influence of seeking financial compensation (i.e., making a claim) on injury recovery following motor vehicle related moderate-severe orthopaedic trauma. Methods: Patients admitted with upper/lower extremity fractures after a motor vehicle crash were recruited from two trauma hospitals. Baseline data were collected in person by written questionnaire within two weeks of injury. Follow up data were collected by a mailed written questionnaire at six, 12 and 24 months. Additional (demographic/injury-related) information was collected from hospital databases, all other measures were self-reported. Outcomes were: Short Form-36 Version 2.0 (SF36v2), Physical/Mental Component Scores (PCS/MCS); Post Traumatic Stress Disorder (PTSD) Checklist Civilian Version (PCL-C); and Global Rating of Change (GRC) scale. Analysis involved descriptive statistics and linear mixed models to examine the effect of compensation status on injury recovery over time. Results: There were 452 study participants. Baseline characteristics showed: mean age 40 years (17.1 Standard Deviation [SD]); 75 % male; 74 % worked pre-injury; 67 % in excellent-very good pre-injury health; 56 % sustained serious injuries, Injury Severity Score (ISS) 9-15; 61 % had a low-middle range household income. Overall, after controlling for possible confounders, the compensable group had poorer recovery compared to the non-compensable group for PCS (-2.97 Mean Difference (MD), 95 % CI -4.73, -1.22); MCS (-3.44 MD, 95 % CI -5. 62, -1.26); PCL-C (3.42MD, 95 % CI 0.87, 5.99); and GRC (-0.66MD, 95 % CI -1.15, -0.17). Injury recovery over time for all participants showed: PCS improved from 6-12 and 12-24 months; MCS and GRC improved from 6-12 months; and PCL-C did not significantly improve from 6-12 and 12-24 months. Injury recovery over time continued for compensable and non-compensable groups but compensable participants had poorer scores at each time period, especially MCS and PCL-C. Conclusions: Making a claim was associated with poor injury recovery following motor vehicle related orthopaedic trauma, mainly for mental health. Irrespective of claim status, the majority had poor injury recovery, especially for mental health

    Haematological Indices and Blood Urea Nitrogen of Yankasa Ram Lambs Fed Urea, Poultry Droppings and or Urea Treated Pennisetum pedicellatum (Kyasuwa Grass)

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    A study was conducted to evaluate the haematological indices and blood urea nitrogen (BUN) of Yankasa ram lambs fed urea and/or poultry droppings treated Kyasuwa (Pennisetum pedicellatum). There were no significant differences (P>0.05) between control treatment (K) and other treatment means observed in the values of packed cell volume (PCV), neutrophils, lymphocytes, eosinophils and basophils. Treatments KU and KPD are significantly different (P < 0.05) from the rest of the treatments in which treatment KPD had the highest value WBC. Blood urea nitrogen from all the treatments were not significantly different (P>0.05) from each other. No ill-health was encountered as a result of feeding treated Kyasuwa with urea and or poultry droppings

    Predictors of return to work following motor vehicle related orthopaedic trauma

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    © 2016 Murgatroyd et al. Background: Work disability following motor vehicle related orthopaedic trauma is a significant contributor to the burden of injury and disease. Early identification of predictors for return to work (RTW) is essential for developing effective interventions to prevent work disability. The study aim was to determine the predictors (including compensation related factors) of time to RTW following motor vehicle related orthopaedic trauma. Methods: Admitted patients were recruited prospectively from two trauma hospitals with upper and/or lower extremity fractures following a motor vehicle crash. Baseline and follow up data were collected by written questionnaire. For baseline, this occurred in person within 2 weeks of injury. For follow up, this occurred by mail at six, 12 and 24 months. Additional demographic and injury-related information was retrieved from hospital databases. Analysis involved: descriptive statistics; logrank test to detect survival distributions of categorical variables; and Cox proportional hazards regression models for risks of time to RTW using baseline characteristic and compensation related variables (at 6 months). Results: Of 452 study participants 334 (74 %) were working pre-injury: results are based on this subset. Baseline characteristics were mean age 36 years (13.9 Standard Deviation [SD]), 80 % male; 72 % self-assessed very good-excellent pre-injury health, 83 % household income > AU$40,000 (Australian Dollar). Follow up data was available for 233 (70 %), 210 (63 %), and 182 (54 %) participants at six, 12 and 24 months respectively. Significant risks of a longer time to RTW were greater injury severity, as measured by the New Injury Severity Score (NISS) (Hazards Rate Ratio [HRR] = 0.54, 95 % CI 0.35-0.82); and lower occupational skill levels (HRR = 0.53, 95 % CI 0.34-0.83). Significant risks of a shorter time to RTW were: recovery expectations for usual activities within 90 days (HRR = 2.10, 95 % CI 1.49-2.95); full-time pre-injury work hours (HRR = 1.99, 95 % CI 1.26-3.14); and very good self-assessed pre-injury health status (HRR = 1.41, 95 % CI 0.98-2.02). Legal representation (analysed at six months only) was not associated with time to RTW. At each time period, there were 146 (63 %), 149 (71 %), and 137 (76 %) working participants. Conclusions: A longer time to RTW was associated with greater injury severity and lower occupational skill levels; while a shorter time to RTW was associated with recovery expectations for usual activities within 90 days, full-time pre-injury work hours, and very good self-assessed pre-injury health status. Our findings reinforce existing research. There is an opportunity to trial interventions that address potentially modifiable factors. The issues surrounding legal representation are complex and require further research

    Prevention of the development of psychological distress following a motor vehicle crash: Study protocol for a randomized controlled trial

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    © 2016 Guest et al. Background: It is estimated that up to 50 % of motor vehicle crash survivors develop significant psychological distress, such as depressive mood and anxiety, within 6 months of the crash. Associated impacts include loss of employment, delayed return to work, financial and familial stress, and increased medical and compensation costs. The major aim of this research is to investigate the efficacy of interventions for preventing the development of psychological distress following a motor vehicle crash. The efficacy of two brief interventions will be examined: a cognitive behaviour therapy (CBT) programme, targeting mood and anxiety, and a lifestyle programme, targeting sleep, diet and physical activity. Methods/design: This is a randomized, controlled multisite study. Participants include at least 180 adults injured in a motor vehicle crash who have entered a compensation process. Research will compare outcomes in three groups randomly assigned to: one group of 60 adults, who receive a brief email-delivered CBT programme, with one session every 2 weeks for 10 weeks and telephone contact every 2 weeks; a second group of 60 adults, who receive a brief email-delivered lifestyle intervention involving one session every 2 weeks for 10 weeks with telephone contact; and an active waiting-list control group of 60 adults who are provided claims processing-related reading material along with telephone contact every 2 weeks for 10 weeks. Participants will be recruited within 12 weeks of the motor vehicle crash, and will be comprehensively assessed before and after treatment, and 6 and 12 months post-injury. Assuming an α probability level of 0.05 and a power of 80 %, at least 180 participants will be recruited. The primary outcome measure is the presence and severity of psychological distress or disorder. Secondary outcome measures include assessment of self-efficacy, resilience employment status, social activity and support, lifestyle and physical health factors, along with process outcome measures of treatment acceptability, feasibility and generalizability. Discussion: This study will determine whether brief email-delivered interventions distributed soon after the injury and entry into the claims process can be effective in preventing the development of psychological distress. Trial registration: ANZCTR, ACTRN12615000326594. Registered on 9 April 2015

    The role of stethoscopes in the transmission of hospital infections

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    Stethoscopes are one of the most commonly used medical devices and have been reported to be potential sources of hospital acquired infections. In this study, we aimed to find out the bacterial contamination of stethoscopes used by health-care staff. Swab samples were taken from the surface of the diaphragm of the stethoscopes used by health personnel in four hospitals including three secondline and one third-line health care institution in Turkey. The samples were inoculated onto bacteriological and mycological media. For identification of the microorganisms, conventional methods and Vitek2 (Biomérieux) were performed. Swab samples were taken from 121 stethoscopes. We found bacterial and fungal contamination on 92 (76%) of the stethoscopes. 15 out 90 (16.3%) had potential pathogens including methicillin susceptible Staphylococcus aureus (5), methicillin resistance Staphylococcus aureus (4), Escherichia coli (3), Acinetobacter baumannii, Acinetobacter haemolyticus and Enterococcus spp. Of the 121 health-care persons, only 61 regularly cleaned their stethoscopes by various disinfectants. The statistical difference between the two groups in terms of pathogen and microorganism isolation was not determined (p>0.05). Although stethoscopes are uncritical medical devices, they could contain pathogen microorganisms and they might be a potential source of hospital acquired infections.Key words: Stethoscopes, hospital infections, Staphylococcus aureus
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