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The Murchison Widefield Array is a low-frequency Square Kilometre Array precursor located at the Murchison Radio-astronomy Observatory in Western Australia. Primarily designed as an imaging telescope, but with a flexible signal path, the capabilities of this telescope have recently been extended to include off-line incoherent and tied-array beam formation using recorded antenna voltages. This has provided the capability for high-time and frequency resolution observations, including a pulsar science program. This paper describes the algorithms and pipeline that we have developed to form the tied-array beam products from the summation of calibrated signals of the antenna elements, and presents example polarimetric profiles for PSRs J0437-4715 and J1900-2600 at 185 MHz.
We apply two methods to estimate the 21-cm bispectrum from data taken within the Epoch of Reionisation (EoR) project of the Murchison Widefield Array (MWA). Using data acquired with the Phase II compact array allows a direct bispectrum estimate to be undertaken on the multiple redundantly spaced triangles of antenna tiles, as well as an estimate based on data gridded to the uv-plane. The direct and gridded bispectrum estimators are applied to 21 h of high-band (167–197 MHz; z = 6.2–7.5) data from the 2016 and 2017 observing seasons. Analytic predictions for the bispectrum bias and variance for point-source foregrounds are derived. We compare the output of these approaches, the foreground contribution to the signal, and future prospects for measuring the bispectra with redundant and non-redundant arrays. We find that some triangle configurations yield bispectrum estimates that are consistent with the expected noise level after 10 h, while equilateral configurations are strongly foreground-dominated. Careful choice of triangle configurations may be made to reduce foreground bias that hinders power spectrum estimators, and the 21-cm bispectrum may be accessible in less time than the 21-cm power spectrum for some wave modes, with detections in hundreds of hours.
Dietary quality (DQ), as assessed by the Alternative Healthy Eating Index for Pregnancy (AHEI-P), and conception and pregnancy outcomes were evaluated.
In this prospective cohort study on couples planning their first pregnancy. Cox proportional hazards regression assessed the relationship between AHEI-P score and clinical pregnancy, live birth and pregnancy loss.
Participants were recruited from the Northeast region of the USA.
Participants: Healthy, nulliparous couples (females, n 132; males, n 131; one male did not enrol).
There were eighty clinical pregnancies, of which sixty-nine resulted in live births and eleven were pregnancy losses. Mean (sd) female AHEI-P was 71·0 (13·7). Of those who achieved pregnancy, those in the highest tertile of AHEI-P had the greatest proportion of clinical pregnancies; however, this association was not statistically significant (P = 0·41). When the time it took to conceive was considered, females with the highest AHEI-P scores were 20 % and 14 % more likely to achieve clinical pregnancy (model 1: hazard ratio (HR) = 1·20; 95 % CI 0·66, 2·17) and live birth (model 1: HR = 1·14; 95 % CI 0·59, 2·20), respectively. Likelihood of achieving clinical pregnancy and live birth increased when the fully adjusted model, including male AHEI-P score, was examined (clinical pregnancy model 4: HR = 1·55; 95 % CI 0·71, 3·39; live birth model 4: HR = 1·36; 95 % CI 0·59, 3·13).
The present study is the first to examine AHEI-P score and achievement of clinical pregnancy. DQ was not significantly related to pregnancy outcomes, even after adjustments for covariates.
Despite the magnitude and protracted nature of the Rohingya refugee situation, there is limited information on the culture, mental health and psychosocial wellbeing of this group. This paper, drawing on a report commissioned by the United Nations High Commissioner for Refugees (UNHCR), aims to provide a comprehensive synthesis of the literature on mental health and psychosocial wellbeing of Rohingya refugees, including an examination of associated cultural factors. The ultimate objective is to assist humanitarian actors and agencies in providing culturally relevant Mental Health and Psychosocial Support (MHPSS) for Rohingya refugees displaced to Bangladesh and other neighbouring countries.
We conducted a systematic search across multiple sources of information with reference to the contextual, social, economic, cultural, mental health and health-related factors amongst Rohingya refugees living in the Asia-Pacific and other regions. The search covered online databases of diverse disciplines (e.g. medicine, psychology, anthropology), grey literature, as well as unpublished reports from non-profit organisations and United Nations agencies published until 2018.
The legacy of prolonged exposure to conflict and persecution compounded by protracted conditions of deprivations and displacement is likely to increase the refugees' vulnerability to wide array of mental health problems including posttraumatic stress disorder, anxiety, depression and suicidal ideation. High rates of sexual and gender-based violence, lack of privacy and safe spaces and limited access to integrated psychosocial and mental health support remain issues of concern within the emergency operation in Bangladesh. Another challenge is the limited understanding amongst the MHPSS personnel in Bangladesh and elsewhere of the language, culture and help-seeking behaviour of Rohingya refugees. While the Rohingya language has a considerable vocabulary for emotional and behavioural problems, there is limited correspondence between these Rohingya terms and western concepts of mental disorders. This hampers the provision of culturally sensitive and contextually relevant MHPSS services to these refugees.
The knowledge about the culture, context, migration history, idioms of distress, help-seeking behaviour and traditional healing methods, obtained from diverse sources can be applied in the design and delivery of culturally appropriate interventions. Attention to past exposure to traumatic events and losses need to be paired with attention for ongoing stressors and issues related to worries about the future. It is important to design MHPSS interventions in ways that mobilise the individual and collective strengths of Rohingya refugees and build on their resilience.
The transient force exerted by a low-speed liquid droplet impinging onto a flat rigid surface is investigated experimentally. The measurements employ a high-sensitivity piezo-electric sensor, along with a high-speed camera, and cover four decades in droplet Reynolds number and greater than two decades in Weber number. Across these ranges, the peak of individual force profiles span from 3 mN to over 1300 mN. Once normalised, the force–time profiles support the existence of an inertially dominated self-similar regime. Within this regime, previous numerical and theoretical studies predict a
dependence of impact normal force during the initial pre-peak rise. While our measurements confirm this finding, they also indicate that, after the peak force the profiles exhibit an exponential decay. This long-time decay law suggests treatment of the momentum transport from the droplet using a lumped model. An observed linear dependence between the force and force decay rate supports this approach. The reason for the efficacy of treating this system via a lumped model apparently connects to the physics right at the surface that limit the rate of momentum transport from the droplet to the surface. This is explored by estimating the momentum transfer by solely using the deforming droplet shape, but under the condition of negligible momentum gradients within the droplet. The short- and long-time solutions are combined and the resulting model equation is shown to accurately cover the entire force–time profile.
After five positive randomized controlled trials showed benefit of mechanical thrombectomy in the management of acute ischemic stroke with emergent large-vessel occlusion, a multi-society meeting was organized during the 17th Congress of the World Federation of Interventional and Therapeutic Neuroradiology in October 2017 in Budapest, Hungary. This multi-society meeting was dedicated to establish standards of practice in acute ischemic stroke intervention aiming for a consensus on the minimum requirements for centers providing such treatment. In an ideal situation, all patients would be treated at a center offering a full spectrum of neuroendovascular care (a level 1 center). However, for geographical reasons, some patients are unable to reach such a center in a reasonable period of time. With this in mind, the group paid special attention to define recommendations on the prerequisites of organizing stroke centers providing medical thrombectomy for acute ischemic stroke, but not for other neurovascular diseases (level 2 centers). Finally, some centers will have a stroke unit and offer intravenous thrombolysis, but not any endovascular stroke therapy (level 3 centers). Together, these level 1, 2, and 3 centers form a complete stroke system of care. The multi-society group provides recommendations and a framework for the development of medical thrombectomy services worldwide.
The ability to prcbe the structure of a polymer during deformation is of considerable technological interest as it lends an insight into the mechanisms involved in polymer processing. The behaviour of Liquid Crystalline Polymers (LCP's) during shear flow has generated much experimental interest by virtue of their unusual behaviour compared to that of simpler polymeric melts. The theory developed by Doi attempts to explain the observed phenomena in terms of considering interactions of rigid-rods Exact solutions to the Doi theory have been compared to experimental procedures using lyotropic LCP systems. Although much of the available data relates to mechanical measurements, the comparisons with quantitative structural data can provide useful insight.
The diffractometer employs dual fixed detectors and a moving, vertically mounted X-ray tube. Lattice strain is measured in two specimen directions simultaneously. The drive has three concentric shafts; the outer driven by a cone drive worm and gear; a middle fixed shaft supporting the detectors and an inner shaft geared in a 1:2 ratio carrying the specimen mount. Scanning angles are measured to an accuracy of ±0.001°. A large range of specimen sizes can be accommodated.
As a result of interest stemming from shock wave studies carried out at Lawrence Livermore Laboratory, we have developed a capability to conduct x-ray diffraction studies in submicrosecond time intervals. This involves the use of a low impedance flash x-ray device. While there are many applications to which these techniques can be put, our first experiments deal with samples undergoing shock wave compression. These particular experiments are conducted by synchronizing a 40 to 50 nsec flash x-ray device to a shock front which is produced by the detonation of a high explosive placed in contact with a sample. Diffracted radiation is usually recorded on very sensitive film protected by a blast cassette. Thus far we have subjected lithium fluoride, aluminum, and carbon to pressures in the range of 100 to 300 kbar. Either powder or single crystal samples can be used. The principal difficulties of this experiment are the lack of sufficient intensity and the synchronization of the x-ray pulse to the shock front.
A computerized systetn, consisting of a fluorescence x-ray source (Philips), an Si (Li) detector (Ortec), and a mini Computer (Xerox) is currentiy in operation at The University of Texas M. D. Anderson Hospital and Tumor Institute, Experimentel Pathology Section, for the analysis of trace elements in biological specimens. The elements of interest are Fe, Cu, and Zn for possible significance in the detection and study of cancer. The detection system is being used for comparatively routine analysis of these elements, which are present in blood serum in the ppM range. With appropriate sample preparation techniques, using 1 ml of serum, the limit of detectability for these elements is estimated to be 100 ppB (1 in 107). Further refinement is possible, and research in this direction continues.
To determine the effectiveness and ease of use of an electronic reminder device in reducing urinary catheterization duration.
A randomized controlled trial with a cross-sectional anonymous online survey and focus group.
Ten wards in an Australian hospital.
All hospitalized patients with a urinary catheter.
An electronic reminder system, the CATH TAG, applied to urinary catheter bags to prompt removal of urinary catheters.
Catheterization duration and perceptions of nurses about the ease of use.
A Cox proportional hazards model was used to assess the rate of removal of catheters. A phenomenological approach underpinned data collection and analysis methods associated with the focus group.
In total, 1,167 patients with a urinary catheter were included. The mean durations in control and intervention phases were 5.51 days (95% confidence interval [CI], 4.9–6.2) and 5.08 days (95% CI, 4.6–5.6), respectively. For patients who had a CATH TAG applied, the hazard ratio (HR) was 1.02 (95% CI, 0.91–1.14; P = .75). A subgroup analysis excluded patients in an intensive care unit (ICU), and the use of the CATH TAG was associated with a 23% decrease in the mean, from 5.00 days (95% CI, 4.44–5.56) to 3.84 days (95% CI, 3.47–4.21). Overall, 82 nurses completed a survey and 5 nurses participated in a focus group. Responses regarding the device were largely positive, and benefits for patient care were identified.
The CATH TAG did not reduce the duration of catheterization, but potential benefits in patients outside the ICU were identified. Electronic reminders may be useful to aid prompt removal of urinary catheters in the non-ICU hospital setting.
The US Agency for Healthcare Research and Quality (AHRQ) Evidence-based Practice Center (EPC) program sponsors the development of systematic reviews to inform clinical policy and practice. The EPC program sought to better understand how health systems identify and use this evidence.
Representatives from eleven EPCs, the EPC Scientific Resource Center, and AHRQ developed a semi-structured interview script to query a diverse group of nine Key Informants (KIs) involved in health system quality, safety and process improvement about how they identify and use evidence. Interviews were transcribed and qualitatively summarized into key themes.
All KIs reported that their organizations have either centralized quality, safety, and process improvement functions within their system, or they have partnerships with other organizations to conduct this work. There was variation in how evidence was identified, with larger health systems having medical librarians and central bureaus to gather and disseminate information and smaller systems having local chief medical officers or individual clinicians do this work. KIs generally prefer guidelines, especially those with treatment algorithms, because they are actionable. They like systematic reviews because they efficiently condense study results and reconcile conflicting data. They prefer information from systematic reviews to be presented as short digestible summaries with the full report available on demand. KIs preferred systematic reviews from reputable entities and those without commercial bias. Some of the challenges KIs reported include how to resolve conflicting evidence, the generalizability of evidence to local needs, determining whether the evidence is up-to-date, and the length of time required to generate reviews. The topics of greatest interest included predictive analytics, high-value care, advance care planning, and care coordination. To increase awareness of AHRQ EPC reviews, KIs suggest alerting people at multiple levels in a health-system when new evidence reports are available and making reports easier to find in common search engines.
Systematic reviews are valued by health system leaders. To be most useful they should be easy to locate and available in different formats targeted to the needs of different audiences.
We sought to explore factors associated with depressive symptom severity among older persons (≥60 years of age) and to compare the depressive symptoms commonly experienced by older elderly (≥75 years) with those commonly experienced by younger elderly (<75 years).
Secondary analysis was conducted on data from a nationally representative survey.
Four parishes in Jamaica.
A total of 2,943 older community dwellers participated.
The survey included the Zung Self-rating Depression Scale (ZSDS), the Mini Mental State Examination (MMSE), and items on age, sex, and educational level. Linear regression analysis was used to determine the association between ZSDS score and: age, sex, MMSE score, and educational level. Logistic regression analysis was used to determine, for each ZSDS item, whether particular responses were more associated with older or younger elderly.
Higher ZSDS scores were associated with increasing age (B = 0.13, p < 0.001), lower MMSE score (B = −0.42, p < 0.001), the female sex (B = 3.52, p < 0.001), and lower educational level (B = −1.27, p < 0.001). The ZSDS items that were endorsed significantly more (p < 0.05) by older elderly related to negative evaluations about their functionality and value. Hopelessness was also more prominent among the older elderly. The items that were endorsed significantly more (p < 0.05) by the younger elderly had less of a focus.
Among older persons, increasing age was associated with marginally higher levels of depressive symptoms. Female gender, cognitive deficits, preoccupations about value and functionality, and feelings of hopelessness may serve as useful screening parameters.
The north-west European population of Bewick’s Swan Cygnus columbianus bewickii declined by 38% between 1995 and 2010 and is listed as ‘Endangered’ on the European Red List of birds. Here, we combined information on food resources within the landscape with long-term data on swan numbers, habitat use, behaviour and two complementary measures of body condition, to examine whether changes in food type and availability have influenced the Bewick’s Swan’s use of their main wintering site in the UK, the Ouse Washes and surrounding fens. Maximum number of Bewick’s Swans rose from 620 in winter 1958/59 to a high of 7,491 in winter 2004/05, before falling to 1,073 birds in winter 2013/14. Between winters 1958/59 and 2014/15 the Ouse Washes supported between 0.5 and 37.9 % of the total population wintering in north-west Europe (mean ± 95 % CI = 18.1 ± 2.4 %). Swans fed on agricultural crops, shifting from post-harvest remains of root crops (e.g. sugar beet and potatoes) in November and December to winter-sown cereals (e.g. wheat) in January and February. Inter-annual variation in the area cultivated for these crops did not result in changes in the peak numbers of swans occurring on the Ouse Washes. Behavioural and body condition data indicated that food supplies on the Ouse Washes and surrounding fens remain adequate to allow the birds to gain and maintain good body condition throughout winter with no increase in foraging effort. Our findings suggest that the recent decline in numbers of Bewick’s Swans at this internationally important site was not linked to inadequate food resources.
The present study aimed to determine the relationship among food insecurity, social support and mental well-being in sub-Saharan Africa, a region presenting the highest prevalence of severe food insecurity and a critical scarcity of mental health care.
Food insecurity was measured using the Food Insecurity Experience Scale (FIES). Social support was assessed using dichotomous indicators of perceived, foreign perceived, received, given, integrative and emotional support. The Negative and Positive Experience Indices (NEI and PEI) were used as indicators of mental well-being. Multilevel mixed-effect linear models were applied to examine the associations between mental well-being and food security status, social support and their interaction, respectively, accounting for random effects at country level and covariates.
Nationally representative adults surveyed through Gallup World Poll between 2014 and 2016 in thirty-nine sub-Saharan African countries (n 102 235).
The prevalence of severe food insecurity was 39 %. The prevalence of social support ranged from 30 to 72 % by type. In the pooled analysis using the adjusted model, food insecurity was dose-responsively associated with increased NEI and decreased PEI. Perceived, integrative and emotional support were associated with lower NEI and higher PEI. The differences in NEI and PEI between people with and without social support were the greatest among the most severely food insecure.
Both food insecurity and lack of social support constitute sources of vulnerability to poor mental well-being. Social support appears to modify the relationship between food security and mental well-being among those most affected by food insecurity in sub-Saharan Africa.