Effect of ultrasonic processing on a direct chill cast AA6082 aluminium alloy

For many years now, ultrasonic melt treatment (UST) has proven itself to promote grain refinement in aluminium alloys. The current work presents cavitation-aided grain refinement obtained on commercial AA6082 DC-cast billets. Grain refinement was achieved while applying UST in the crucible away from the sump, prior to casting. Since in high strength alloys, Zr and Ti are commonly present as alloying elements for anti-recrystallization and corrosion resistance properties, their as well as UST parameters influence on the microstructure are studied and presented. Primary Al3(Zr1-x-y ,Tix , Siy) intermetallics were found in the centre of the α-Al grains. This suggests that UST may have forced the nucleation and refinement of primary intermetallics influencing the subsequent solidification process when Al3(Zr1-x-y , Tix , Siy) act as nucleation sites

Altering the Microstructure Morphology by Ultrasound Melt Processing during 6XXX Aluminium DC-Casting

EPSRC (UK

Development and testing the feasibility of a sports-based mental health promotion intervention in Nepal: a protocol for a pilot cluster-randomised controlled trial

Background: Mental wellbeing encompasses life satisfaction, social connectedness, agency and resilience. In adolescence, mental wellbeing reduces sexual health risk behaviours, substance use and violence; improves educational outcomes; and protects mental health in adulthood. Mental health promotion seeks to improve mental wellbeing and can include activities to engage participants in sport. However, few high-quality trials of mental health promotion interventions have been conducted with adolescents, especially in low- and middle-income countries. We sought to address this gap by testing SMART (Sports-based Mental heAlth pRomotion for adolescenTs) in a pilot cluster-randomised controlled trial (cRCT) in Bardiya, Nepal. // Methods: The objectives of the trial are to assess the acceptability and feasibility of SMART, test trial procedures, explore outcome distributions in intervention and control clusters and calculate the total annual cost of the intervention and unit cost per adolescent. The trial design is a parallel-group, two-arm superiority pilot cRCT with a 1:1 allocation ratio and two cross-sectional census surveys with adolescents aged 12–19, one pre-intervention (baseline) and one post-intervention (endline). The study area is four communities of approximately 1000 population (166 adolescents per community). Each community represents one cluster. SMART comprises twice weekly football, martial arts and dance coaching, open to all adolescents in the community, led by local sports coaches who have received psychosocial training. Sports melas (festivals) and theatre performances will raise community awareness about SMART, mental health and the benefits of sport. Adolescents in control clusters will participate in sport as usual. In baseline and endline surveys, we will measure mental wellbeing, self-esteem, self-efficacy, emotion regulation, social support, depression, anxiety and functional impairment. Using observation checklists, unstructured observation and attendance registers from coaching sessions, and minutes of meetings between coaches and supervisors, we will assess intervention fidelity, exposure and reach. In focus group discussions and interviews with coaches, teachers, caregivers and adolescents, we will explore intervention acceptability and mechanisms of change. Intervention costs will be captured from monthly project accounts, timesheets and discussions with staff members. // Discussion: Findings will identify elements of the intervention and trial procedures requiring revision prior to a full cRCT to evaluate the effectiveness of SMART

Survey instruments used in clinical and epidemiological research on waterpipe tobacco smoking: a systematic review

<p>Abstract</p> <p>Background</p> <p>The primary objective was to systematically review the medical literature for instruments validated for use in epidemiological and clinical research on waterpipe smoking.</p> <p>Methods</p> <p>We searched the following databases: MEDLINE, EMBASE, and ISI the Web of Science. We selected studies using a two-stage duplicate and independent screening process. We included papers reporting on the development and/or validation of survey instruments to measure waterpipe tobacco consumption or related concepts. Two reviewers used a standardized and pilot tested data abstraction form to collect data from each eligible study using a duplicate and independent screening process. We also determined the percentage of observational studies assessing the health effects of waterpipe tobacco smoking and the percentage of studies of prevalence of waterpipe tobacco smoking that have used validated survey instruments.</p> <p>Results</p> <p>We identified a total of five survey instruments. One instrument was designed to measure knowledge, attitudes, and waterpipe use among pregnant women and was shown to have internal consistency and content validity. Three instruments were designed to measure waterpipe tobacco consumption, two of which were reported to have face validity. The fifth instrument was designed to measure waterpipe dependence and was rigorously developed and validated. One of the studies of prevalence and none of the studies of health effects of waterpipe smoking used validated instruments.</p> <p>Conclusions</p> <p>A number of instruments for measuring the use of and dependence on waterpipe smoking exist. Future research should study content validity and cross cultural adaptation of these instruments.</p

Public health benefits of shifting from inpatient to outpatient TB care in Eastern Europe: optimising TB investments in Belarus, the Republic of Moldova, and Romania

Background: High rates of drug-resistant tuberculosis (DR TB) continue to threaten public health, especially in Eastern Europe. Costs for treating DR TB are substantially higher than treating drug-susceptible TB, and higher yet if DR TB services are delivered in hospital. Therefore, countries are encouraged to transition from inpatient to ambulatory-focused TB care, which has been shown to have non-inferior health outcomes. / Methods: Allocative efficiency analyses were conducted for three countries in Eastern Europe, Belarus, the Republic of Moldova, and Romania to minimise a combination of active TB cases, prevalence of active TB, and TB-related deaths by 2035. These mathematical optimisations were carried out using Optima TB, a dynamical compartmental model of TB transmission. The focus of this study was to project the health and financial gains that could be realised if TB service delivery shifted from hospital to ambulatory-based care. / Findings: These analyses show that transitioning from inpatient to ambulatory TB care could reduce treatment costs by 5%−31% or almost 35 million US dollars across these three countries without affecting the quality of care. Improved TB outcomes could be achieved without additional spending by reinvesting these potential savings in cost-effective prevention and diagnosis interventions. / Conclusions: National governments should examine barriers delaying the adoption of outpatient DR TB care and consider the lost opportunities caused by delays in switching to more efficient and effective treatment modes

Public health benefits of shifting from hospital-focused to ambulatory TB care in Eastern Europe: Optimising TB investments in Belarus, the Republic of Moldova, and Romania

High rates of drug-resistant tuberculosis (DR-TB) continue to threaten public health, especially in Eastern Europe. Costs for treating DR-TB are substantially higher than treating drug-susceptible TB, and higher yet if DR-TB services are delivered in hospital. The WHO recommends that multidrug-resistant (MDR) TB be treated using mainly ambulatory care, shown to have non-inferior health outcomes, however, there has been a delay to transition away from hospital-focused MDR-TB care in certain Eastern European countries. Allocative efficiency analyses were conducted for three countries in Eastern Europe, Belarus, the Republic of Moldova, and Romania, to minimise a combination of TB incidence, prevalence, and mortality by 2035. A primary focus of these studies was to determine the health benefits and financial savings that could be realised if DR-TB service delivery shifted from hospital-focused to ambulatory care. Here we provide a comprehensive assessment of findings from these studies to demonstrate the collective benefit of transitioning from hospital-focused to ambulatory TB care, and to address common regional considerations. We highlight that transitioning from hospital-focused to ambulatory TB care could reduce treatment costs by 20% in Romania, 24% in Moldova, and by as much as 40% in Belarus or almost 35 million US dollars across these three countries by 2035 without affecting quality of care. Improved TB outcomes could be achieved, however, without additional spending by reinvesting these savings in higher-impact TB diagnosis and more efficacious DR-TB treatment regimens. We found commonalities in the large portion of TB cases treated in hospital across these three regional countries, and similar obstacles to transitioning to ambulatory care. National governments in the Eastern European region should examine barriers delaying adoption of ambulatory DR-TB care and consider lost opportunities caused by delays in switching to more efficient treatment modes

Rapid expression and purification of the hepatitis delta virus antigen using the methylotropic yeast Pichia pastoris

Objective: Patients with dual hepatitis B (HBV) and hepatitis D (HDV) virus infection are at an increased risk of progression to liver cirrhosis and hepatocellular carcinoma than patients with a single viral infection. Treatment of viral hepatitis due to dual HBV/HDV infection represents a challenge. Currently there is no vaccine against HDV. Recombinant production of HDV antigen (HDAg) is the first step towards a potential vaccine candidate and the development of assays for HDV detection. Results: This study demonstrates the expression of one HDAg isoform, S-HDAg, in Pichia pastoris. A recombinant vector carrying a tagged gene encoding S-HDAg under the control of the methanol-inducible promoter AOX1 was designed and integrated into P. pastoris X33. The protein, which was purified using a Ni2+ affinity column and eluted at 100-150 mM imidazole, has potential as a recombinant antigen for further study

Accurate detection of spontaneous seizures using a generalized linear model with external validation

Objective Seizure detection is a major facet of electroencephalography (EEG) analysis in neurocritical care, epilepsy diagnosis and management, and the instantiation of novel therapies such as closed-loop stimulation or optogenetic control of seizures. It is also of increased importance in high-throughput, robust, and reproducible pre-clinical research. However, seizure detectors are not widely relied upon in either clinical or research settings due to limited validation. In this study, we create a high-performance seizure-detection approach, validated in multiple data sets, with the intention that such a system could be available to users for multiple purposes. Methods We introduce a generalized linear model trained on 141 EEG signal features for classification of seizures in continuous EEG for two data sets. In the first (Focal Epilepsy) data set consisting of 16 rats with focal epilepsy, we collected 1012 spontaneous seizures over 3 months of 24/7 recording. We trained a generalized linear model on the 141 features representing 20 feature classes, including univariate and multivariate, linear and nonlinear, time, and frequency domains. We tested performance on multiple hold-out test data sets. We then used the trained model in a second (Multifocal Epilepsy) data set consisting of 96 rats with 2883 spontaneous multifocal seizures. Results From the Focal Epilepsy data set, we built a pooled classifier with an Area Under the Receiver Operating Characteristic (AUROC) of 0.995 and leave-one-out classifiers with an AUROC of 0.962. We validated our method within the independently constructed Multifocal Epilepsy data set, resulting in a pooled AUROC of 0.963. We separately validated a model trained exclusively on the Focal Epilepsy data set and tested on the held-out Multifocal Epilepsy data set with an AUROC of 0.890. Latency to detection was under 5 seconds for over 80% of seizures and under 12 seconds for over 99% of seizures. Significance This method achieves the highest performance published for seizure detection on multiple independent data sets. This method of seizure detection can be applied to automated EEG analysis pipelines as well as closed loop interventional approaches, and can be especially useful in the setting of research using animals in which there is an increased need for standardization and high-throughput analysis of large number of seizures

Controlled ultraviolet (UV) photoinitiated fabrication of monolithic porous layer open tubular (monoPLOT) capillary columns for chromatographic applications

An automated column fabrication technique that is based on a ultraviolet (UV) light-emitting diode (LED) array oven, and provides precisely controlled "in-capillary" ultraviolet (UV) initiated polymerization at 365 nm, is presented for the production of open tubular monolithic porous polymer layer capillary (monoPLOT) columns of varying length, inner diameter (ID), and porous layer thickness. The developed approach allows the preparation of columns of varying length, because of an automated capillary delivery approach, with precisely controlled and uniform layer thickness and monolith morphology, from controlled UV power and exposure time. The relationships between direct exposure times, intensity, and layer thickness were determined, as were the effects of capillary delivery rate (indirect exposure rate), and multiple exposures on the layer thickness and axial distribution. Layer thickness measurements were taken by scanning electron microscopy (SEM), with the longitudinal homogeneity of the stationary phase confirmed using scanning capacitively coupled contactless conductivity detection (sC(4)D). The new automated UV polymerization technique presented in this work allows the fabrication of monoPLOT columns with a very high column-to-column production reproducibility, displaying a longitudinal phase thickness variation within ±0.8% RSD (relative standard deviation)