Single-Exposure, Single-Mask, Edge-Illumination X-ray Phase-Contrast Imaging Using a 7.8-μm Pixel Pitch Direct Conversion X-ray Detector

Double-mask edge-illumination is a well-reported technique for phase-contrast x-ray imaging. Although phase retrieval using this technique is comparably easier than propagation-based phase-contrast x-ray imaging, edge-illumination can be inefficient in terms of dose efficiency and imaging time when it comes to computed tomography scanning. The illumination curve, which describes the beamlets' intensity profile impinging upon the detector, is a key parameter that contributes to retrieving phase and absorption information. To obtain the illumination curve, multiple exposures are typically required which decreases x-ray dose efficiency and, more importantly, increases imaging time. Moreover, sample motion can negatively impact the image and information retrieval process. In this research, we employ a single mask in conjunction with a 7.8-μm pixel pitch amorphous selenium-CMOS hybrid direct conversion x-ray detector to obtain the beamlets' intensity profile with only a single exposure. We demonstrate how using an ultra-high spatial resolution x-ray detector with a single-mask edge-illumination technique can potentially increase both dose efficiency and imaging time by at least a factor of 1.5X. Moreover, the resulting system using our approach is more compact with a source-to-detector distance of less than 30 cm. Single-exposure imaging can also help mitigate the impact of motion artifacts in the final image

Towards Sustainable Municipal Solid Waste Management in Malaysia

This work is part of the SYNERGORS project (“A Systems Approach to Synergistic Utilisation of Secondary Organic Streams”) funded by the UKRI Natural Environment Research Council (NE/R012938/1) through the UKRI/NERC Industrial Innovation Fellowship Programme (2018-2021). This project was led by Dr Kok Siew Ng at University of Oxford. Website: https://eng.ox.ac.uk/synergorsProject summary report: https://eng.ox.ac.uk/media/10670/synergors-final-report.pdfEXECUTIVE SUMMARY: The increasing amount of municipal solid waste (MSW) generation and the lack of strategic improvements on solid waste management in Malaysia require urgently the attention of the government and the public.It has been estimated that 1.17 kg/capita/day of MSW is generated in Malaysia, 65% of which is household solid waste that has doubled over the past 20 years due to population growth and urbanisation. Without a sufficient waste treatment and recycling infrastructure in place, most of the MSW is destined to continue to be landfilled. Not only it can cause pollution and health hazards, MSW is also one of the major sources of global methane emissions accounting for 11%. As methane is the second largest contributor of global greenhouse gas emissions after carbon dioxide, it is critical that Malaysia develops systemic sound solid waste management as part of its climate actions guided by the Paris agreement. Also, by treating waste as resource, the recent shift in the government strategy to move towards the circular economy should be aligned with SDG 12 targets (Responsible Consumption and Production). Although the quantity of recyclable waste collected tripled between 2018 and 2021, the officially reported recycling rate of 31.5% in 2021 remains questionable as the recycling infrastructure in Malaysia is not yet well established. This points to the significant efforts Malaysia needs to make to move towards a sustainable waste management regime, and to achieve its ambition for reaching a recycling target of 40% by 2025. Malaysia started implementing a plan for moving towards sustainable waste management in the early 1990s. However, the recycling programmes were not well received by the public at that time, and it was only in 2001, that policy goals for sustainable waste management have been included in the regulatory landscape through the 8th Malaysia Plan (2001-2005). In 2005, the National Strategic Plan for Solid Waste Management was developed to guide solid waste policy planning and resource allocation. Two years after, the Solid Waste and Public Cleansing Management Act 2007 (Act 672) was created that came into enforcement in September 2011 in six out of the thirteen states (Perlis, Kedah, Pahang, Negeri Sembilan, Melaka, Johor) and two out of the three federal territories (i.e. Kuala Lumpur and Putrajaya). This partial adoption of the Act has created inconsistency in waste management and planning as well as incomplete waste data gathering. This,has led to ineffective waste management practices, that, in turn, resulted in long-term environmental, economic and social consequences. Even though sustainable waste management goals continue to be included in the recent 12th Malaysia Plan (2021-2025), the lack of public awareness on the importance of source separation of waste and recycling prevents progress in this field. The infrastructure for waste collection and treatment is also insufficient to serve the needs. All these factors have created significant barriers for Malaysia to realise sustainable waste management.UK Natural Environment Research Council (NE/R012938/1

A massive proto-cluster of galaxies at a redshift of z {\approx} 5.3

Massive clusters of galaxies have been found as early as 3.9 Billion years (z=1.62) after the Big Bang containing stars that formed at even earlier epochs. Cosmological simulations using the current cold dark matter paradigm predict these systems should descend from "proto-clusters" - early over-densities of massive galaxies that merge hierarchically to form a cluster. These proto-cluster regions themselves are built-up hierarchically and so are expected to contain extremely massive galaxies which can be observed as luminous quasars and starbursts. However, observational evidence for this scenario is sparse due to the fact that high-redshift proto-clusters are rare and difficult to observe. Here we report a proto-cluster region 1 billion years (z=5.3) after the Big Bang. This cluster of massive galaxies extends over >13 Mega-parsecs, contains a luminous quasar as well as a system rich in molecular gas. These massive galaxies place a lower limit of >4x10^11 solar masses of dark and luminous matter in this region consistent with that expected from cosmological simulations for the earliest galaxy clusters.Comment: Accepted to Nature, 16 Pages, 6 figure

TbUNC119 and Its Binding Protein Complex Are Essential for Propagation, Motility, and Morphogenesis of Trypanosoma brucei Procyclic Form Cells

Flagellum-mediated motility of Trypanosoma brucei is considered to be essential for the parasite to complete stage development in the tsetse fly vector, while the mechanism by which flagellum-mediated motility is controlled are not fully understood. We thus compared T. brucei whole gene products (amino acid sequence) with Caenorhabditis elegans UNC (uncoordinated) proteins, in order to find uncharacterized motility-related T. brucei genes. Through in silico analysis, we found 88 gene products which were highly similar to C. elegans UNC proteins and categorized them as TbCEUN (T. brucei gene products which have high similarity to C. elegans UNC proteins). Approximately two thirds of the 88 TbCEUN gene products were kinesin-related molecules. A gene product highly similar to C. elegans UNC119 protein was designated as TbUNC119. RNAi-mediated depletion of TbUNC119 showed no apparent phenotype. However, knock-down analysis of both TbUNC119 and its binding protein (TbUNC119BP) which was found by yeast two-hybrid analysis showed characteristic phenotypes, including reduced motility, morphological change (extended cell shape), and cellular apoptosis. Based on the observed phenotypes, possible function of the TbUNC119 and TbUNC119BP is discussed

Validation of the Internet Addiction Test in Students at a Pakistani Medical and Dental School

Despite growing concerns over pathological internet usage, studies based on validated psychometric instruments are still lacking in Pakistan. This study aimed to examine the psychometric properties of the Internet Addiction Test (IAT) in a sample of Pakistani students. A total of 522 students of medicine and dentistry completed the questionnaire, which consisted of four sections: (a) demographics, (b) number of hours spent on the Internet per day, (c) English version of the IAT, and (d) the Defense Style Questionnaire-40. Maximum likelihood analysis and principal axis factoring were used to validate the factor structure of the IAT. Convergent and criterion validity were assessed by correlating IAT scores with number of hours spent online and defense styles. Exploratory and confirmatory factor analysis reflected the goodness of fit of a unidimensional structure of the IAT, with a high alpha coefficient. The IAT had good face and convergent validity and no floor and ceiling effects, and was judged easy to read by participants

Institutional and behaviour-change interventions to support COVID-19 public health measures: a review by the Lancet Commission Task Force on public health measures to suppress the pandemic

The Lancet COVID-19 Commission Task Force for Public Health Measures to Suppress the Pandemic was launched to identify critical points for consideration by governments on public health interventions to control coronavirus disease 2019 (COVID-19). Drawing on our review of published studies of data analytics and modelling, evidence synthesis and contextualisation, and behavioural science evidence and theory on public health interventions from a range of sources, we outline evidence for a range of institutional measures and behaviour-change measures. We cite examples of measures adopted by a range of countries, but especially jurisdictions that have, thus far, achieved low numbers of COVID-19 deaths and limited community transmission of severe acute respiratory syndrome coronavirus 2. Finally, we highlight gaps in knowledge where research should be undertaken. As countries consider long-term measures, there is an opportunity to learn, improve the response and prepare for future pandemics

Analysis of coding variants in the betacellulin gene in type 2 diabetes and insulin secretion in African American subjects

BACKGROUND: Betacellulin is a member of the epidermal growth factor family, expressed at the highest levels predominantly in the pancreas and thought to be involved in islet neogenesis and regeneration. Nonsynonymous coding variants were reported to be associated with type 2 diabetes in African American subjects. We tested the hypotheses that these previously identified variants were associated with type 2 diabetes in African Americans ascertained in Arkansas and that they altered insulin secretion in glucose tolerant African American subjects. METHODS: We typed three variants, exon1 Cys7Gly (C7G), exon 2 Leu44Phe (L44F), and exon 4 Leu124Met (L124M), in 188 control subjects and 364 subjects with type 2 diabetes. We tested for altered insulin secretion in 107 subjects who had undergone intravenous glucose tolerance tests to assess insulin sensitivity and insulin secretion. RESULTS: No variant was associated with type 2 diabetes, and no variant altered insulin secretion or insulin sensitivity. However, an effect on lipids was observed for all 3 variants, and variant L124M was associated with obesity measures. CONCLUSION: We were unable to confirm a role for nonsynonymous variants of betacellulin in the propensity to type 2 diabetes or to impaired insulin secretion

Assessing the implementation effectiveness and safety of 1% tenofovir gel provision through family planning services in KwaZulu-Natal, South Africa: study protocol for an open-label randomized controlled trial.

CAPRISA, 2014.Background: The Centre for the AIDS Programme of Research in South Africa (CAPRISA) 004 trial demonstrated a 39% reduction in HIV infection, with a 54% HIV reduction in women who used tenofovir gel consistently. A confirmatory trial is expected to report results in early 2015. In the interim, we have a unique window of opportunity to prepare for and devise effective strategies for the future policy and programmatic scale-up of tenofovir gel provision. One approach is to integrate tenofovir gel provision into family planning (FP) services. The CAPRISA 008 implementation trial provides an opportunity to provide post-trial access to tenofovir gel while generating empiric evidence to assess whether integrating tenofovir gel provision into routine FP services can achieve similar levels of adherence as the CAPRISA 004 trial. Methods/design: This is a two-arm, open-label, randomized controlled non-inferiority trial. A maximum of 700 sexually active, HIV-uninfected women aged 18 years and older who previously participated in an antiretroviral prevention study will be enrolled from an urban and rural site in KwaZulu-Natal, South Africa. The anticipated study duration is 30 months, with active accrual requiring approximately 12 months (following which an open cohort will be maintained) and follow-up continuing for approximately 18 months. At each of the two sites, eligible participants will be randomly assigned to receive tenofovir gel through either FP services (intervention arm) or through the CAPRISA research clinics (control arm). As part of the study intervention, a quality improvement approach will be used to assist the FP services to expand their current services to include tenofovir gel provision. Discussion: This protocol aims to address an important implementation question on whether FP services are able to effectively incorporate tenofovir gel provision for this at-risk group of women in South Africa. Provision of tenofovir gel to the women from the CAPRISA 004 trial meets the ethical obligation for post-trial access, and helps identify a potential avenue for future scale-up of microbicides within the public health system of South Africa. Trial registration: This trial was registered with the South Africa Department of Health (reference: DOH-27-0812-4129) and ClinicalTrials.gov (reference: NCT01691768) on 05 July 2012

Utilisation of an operative difficulty grading scale for laparoscopic cholecystectomy

Background A reliable system for grading operative difficulty of laparoscopic cholecystectomy would standardise description of findings and reporting of outcomes. The aim of this study was to validate a difficulty grading system (Nassar scale), testing its applicability and consistency in two large prospective datasets. Methods Patient and disease-related variables and 30-day outcomes were identified in two prospective cholecystectomy databases: the multi-centre prospective cohort of 8820 patients from the recent CholeS Study and the single-surgeon series containing 4089 patients. Operative data and patient outcomes were correlated with Nassar operative difficultly scale, using Kendall’s tau for dichotomous variables, or Jonckheere–Terpstra tests for continuous variables. A ROC curve analysis was performed, to quantify the predictive accuracy of the scale for each outcome, with continuous outcomes dichotomised, prior to analysis. Results A higher operative difficulty grade was consistently associated with worse outcomes for the patients in both the reference and CholeS cohorts. The median length of stay increased from 0 to 4 days, and the 30-day complication rate from 7.6 to 24.4% as the difficulty grade increased from 1 to 4/5 (both p < 0.001). In the CholeS cohort, a higher difficulty grade was found to be most strongly associated with conversion to open and 30-day mortality (AUROC = 0.903, 0.822, respectively). On multivariable analysis, the Nassar operative difficultly scale was found to be a significant independent predictor of operative duration, conversion to open surgery, 30-day complications and 30-day reintervention (all p < 0.001). Conclusion We have shown that an operative difficulty scale can standardise the description of operative findings by multiple grades of surgeons to facilitate audit, training assessment and research. It provides a tool for reporting operative findings, disease severity and technical difficulty and can be utilised in future research to reliably compare outcomes according to case mix and intra-operative difficulty

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO