2,203 research outputs found

    Fate of mercury in tree litter during decomposition

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    We performed a controlled laboratory litter incubation study to assess changes in dry mass, carbon (C) mass and concentration, mercury (Hg) mass and concentration, and stoichiometric relations between elements during decomposition. Twenty-five surface litter samples each, collected from four forest stands, were placed in incubation jars open to the atmosphere, and were harvested sequentially at 0, 3, 6, 12, and 18 months. Using a mass balance approach, we observed significant mass losses of Hg during decomposition (5 to 23 % of initial mass after 18 months), which we attribute to gaseous losses of Hg to the atmosphere through a gas-permeable filter covering incubation jars. Percentage mass losses of Hg generally were less than observed dry mass and C mass losses (48 to 63 % Hg loss per unit dry mass loss), although one litter type showed similar losses. A field control study using the same litter types exposed at the original collection locations for one year showed that field litter samples were enriched in Hg concentrations by 8 to 64 % compared to samples incubated for the same time period in the laboratory, indicating strong additional sorption of Hg in the field likely from atmospheric deposition. Solubility of Hg, assessed by exposure of litter to water upon harvest, was very low (<0.22 ng Hg g<sup>−1</sup> dry mass) and decreased with increasing stage of decomposition for all litter types. Our results indicate potentially large gaseous emissions, or re-emissions, of Hg originally associated with plant litter upon decomposition. Results also suggest that Hg accumulation in litter and surface layers in the field is driven mainly by additional sorption of Hg, with minor contributions from "internal" accumulation due to preferential loss of C over Hg. Litter types showed highly species-specific differences in Hg levels during decomposition suggesting that emissions, retention, and sorption of Hg are dependent on litter type

    Innovative Techniques for 60-GHz On-Chip Antennas on CMOS Substrate

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    The 60-GHz band has a 7-GHz of bandwidth enabling high data rate wireless communication. Also, it has a short wavelength allowing for passive devices integration into a chip, that is, fully integrated system-on-chip (SOC) is possible. This chapter features the design, implementation, and measurements of 60-GHz on-chip antennas (OCAs) on complementary-metal-oxide-semiconductor (CMOS) technology. OCAs are the primary barrier for the SOC solution due to their limited performance. This degraded performance comes from the low resistivity and the high permittivity of the CMOS substrate. We present here two innovative techniques to improve the CMOS OCAs’ performance. The first method utilizes artificial magnetic conductors to shield the OCA electromagnetically from the CMOS substrate. The second methodology employs the PN-junction properties to create a high resistivity layer. Both approaches target the mitigation of the losses of the CMOS substrate; hence, the radiation performance characteristics of the OCAs are enhanced

    Counselling-based psychosocial intervention to improve the mental health of abused pregnant women: A protocol for randomised controlled feasibility trial in a tertiary hospital in eastern Nepal

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    © 2019 Author(s). Published by BMJ. Introduction The strong correlation between domestic and family violence (DFV) and mental health has been well documented in studies. Pregnancy is a period when both DFV and mental distress tend to occur and/or accentuate. Although limited, available evidence from developed countries has shown continual support and education as psychological first aid that can reduce DFV and improve mental health. However, there is significantly less number of studies from resource-constrained countries; thus, there continues to be a substantial gap in knowledge and awareness regarding effective interventions for DFV. Methods and analysis A two-arm randomised trial with a nested qualitative study has been planned to assess feasibility and treatment effect estimates of a counselling-based psychosocial intervention among pregnant women with a history of abuse. A total of 140 pregnant women who meet the inclusion criteria will be recruited into the study. Block randomisation will be used to allocate women equally into two groups. The intervention group will receive a counselling session, an information booklet and continuous support by a researcher, while women in the control group will receive contact information of local support services. Feasibility measures, such as rates of recruitment, consent and retention, will be calculated. Qualitative interviews with participants and healthcare providers will explore the acceptability and usability of the intervention. Outcome measures, such as psychological distress, quality of life, social support and self-efficacy, will be measured at baseline, 4 weeks postintervention and 6 weeks postpartum. Ethics and dissemination This study has obtained ethical approval from the Griffith University Human Research Ethics Committee, the Nepal Health Research Council and the Institutional Review Board of a tertiary hospital in Dharan, Nepal. The findings will be disseminated via peer-reviewed publications and conference presentations and will be used to inform a future multicentre trial

    'We don't see because we don't ask': Qualitative exploration of service users' and health professionals' views regarding a psychosocial intervention targeting pregnant women experiencing domestic and family violence.

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    INTRODUCTION:Given the relative recency of Domestic and Family Violence (DFV) management as a field of endeavour, it is not surprising that interventions for addressing DFV is still in its infancy in developing countries. In order to maximise the success of an intervention, it is important to know which aspects of the intervention are considered important and helpful by service providers and service users. This study, therefore, examined the acceptability of an antenatal-based psychosocial intervention targeting DFV in Nepal and explored suggestions for improving the program in future. MATERIALS AND METHODS:Intervention participants and health care providers (HCPs) were interviewed using semi-structured interviews. Data were audio-recorded and thematic analysis was used to analyse the data. Final codes and themes were identified using an iterative review process among the research team. RESULTS:Themes emerging from the data were grouped into domains including perceptions towards DFV, impact of the intervention on women's lives and recommendations for improving the program. DFV was recognised as a significant problem requiring urgent attention for its prevention and control. Intervention participants expressed that they felt safe to share their feelings during the counselling session and got opportunity to learn new skills to cope with DFV. The majority of the participants recommended multiple counselling sessions and a continued provision of the service ensuring the intervention's accessibility by a large number of women. DISCUSSION:This is the first study to document the perspectives of women and HCPs regarding an antenatal-based intervention targeting psychosocial consequences of DFV in Nepal. There was a clear consensus around the need to engage, support and empower victims of DFV and the intervention was well received by the participants. Ensuring good mental health and wellbeing among victims of DFV requires work across individual, organisational and community levels

    Development and Validation of an Information Booklet Aimed at Promoting Mental Health for Pregnant Women with a History of Abuse.

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    BACKGROUND:Mental health needs of victims of domestic and family violence are often overlooked. A booklet was designed to help women update their knowledge and skills in effective coping with domestic and family violence and support them in developing effective stress reduction and problem management techniques. In addition, this booklet is believed to serve as a reference for further use. This paper describes the development process and validation of the information booklet. This booklet was used during an intervention trial conducted in Nepal to educate abused pregnant women. METHODS:This methodological study involved three stages: bibliographical survey, development of the booklet, and validation by specialists in the relevant fields and representatives of the target audiences. A total of eight experts, currently working in the field of domestic violence and/or midwifery, and 15 representatives of the target participants were involved in the validation process. A minimum Content Validity Index of 0.78 was considered for content validation, and minimum agreement of 75% for face validation. RESULTS:The booklet presented a global Content Validity Index of 0.92. The overall level of agreement within the target participants was 86.3%, which was higher than the minimum recommended level. Both subject experts and participants positively evaluated the adequacy, coverage and readability of contents of the booklet. CONCLUSIONS:The booklet was validated using content and face validity. This validated booklet is expected to be an effective tool for communication that would help pregnant women cope better with domestic and family violence and adopt strategies to remain emotionally healthy

    SOCIO-PSYCHOLOGICAL STUDY AMONG INJECTABLE DRUG USERS IN KATHMANDU VALLEY

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    On the background of ever increasing HIV transmission in our community through various routes, the psychosocial factors related with intravenous drug abuse has become necessary to be studied. Aim of the study was to assess the Socio-psychological factors that influence people to use drugs, especially to use Injectable drugs. We enrolled a sample of 393 Intravenous drug users, all male, in the Kathmandu Valley. Participants were administered a semi structured proforma to assess the psychosocial issues related with the drug intravenous drug abuse. Mean age of the sample was 27.76+ 4.86 years. Majority were single, unemployed, Hindu and by caste Newars, with education more than high school (SLC or more). The first psychoactive substance use by most of them was cannabis. The most frequently used psychoactive substance was injection Buprenorphine (Tidigesic), which was followed by mixture of various substances (opiates, benzodiazepines, antihistamines) and Diacetyl morphine (Brown sugar). Factors associated with the start of the drugs were for enjoyment, friend’s pressure and to alleviate mental tension. Many accepted Injectable drug use contributing to problems in mental, marital, social, economic and legal aspects of their life. Despite knowing the harms caused by the drugs majority persist on its use. A needle exchange programme has been viewed positively by many. Key words: buprenorphin, needle sharing, needle replacement, HIV transmission

    Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

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    This paper presents measurements of the W+μ+νW^+ \rightarrow \mu^+\nu and WμνW^- \rightarrow \mu^-\nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

    Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector

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    A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV
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