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The objective of this study is to compare aneuploidy rates between three distinct areas of the human trophectoderm: mural, polar and a region in between these two locations termed the ‘mid’ trophectoderm. This is a cohort study on in vitro fertilization (IVF) patients undergoing comprehensive chromosome screening at the blastocyst stage at a private IVF clinic. All embryos underwent assisted hatching on day 3 with blastocyst biopsy and comprehensive chromosome screening. Biopsied blastocysts were divided into three groups depending on which area (polar, mid, or mural) of the trophectoderm was protruding from the zona pellucida and biopsied. Aneuploidy rates were significantly higher with cells from the polar region of the trophectoderm (56.2%) compared with cells removed from the mural region of the trophectoderm (30.0%; P = 0.0243). A comparison of all three areas combined also showed a decreasing trend, but this did not reach clinical significance, polar (56.2%), mid (47.4%) and mural trophectoderm (30.0%; P = 0.1859). The non-concordance demonstrated between polar and mural trophectoderm can be attributed to biological occurrences including chromosomal mosaicism or procedural differences between embryologists.
The RemoveDEBRIS mission has been the first mission to successfully demonstrate, in-orbit, a series of technologies that can be used for the active removal of space debris. The mission started late in 2014 and was sponsored by a grant from the EC that saw a consortium led by the Surrey Space Centre to develop the mission, from concept to in-orbit demonstrations, that terminated in March 2019. Technologies for the capture of large space debris, like a net and a harpoon, have been successfully tested together with hardware and software to retrieve data on non-cooperative target debris kinematics from observations carried out with on board cameras. The final demonstration consisted of the deployment of a drag-sail to increase the drag of the satellite to accelerate its demise.
We show that the isomorphism problems for left distributive algebras, racks, quandles and kei are as complex as possible in the sense of Borel reducibility. These algebraic structures are important for their connections with the theory of knots, links and braids. In particular, Joyce showed that a quandle can be associated with any knot, and this serves as a complete invariant for tame knots. However, such a classification of tame knots heuristically seemed to be unsatisfactory, due to the apparent difficulty of the quandle isomorphism problem. Our result confirms this view, showing that, from a set-theoretic perspective, classifying tame knots by quandles replaces one problem with (a special case of) a much harder problem.
Social movements have increasingly incorporated legal strategies into their repertoires of contention. Yet, both sociolegal and social movement scholarship lack a systematic and theoretically coherent way to conceptualize legal mobilization. In fact, scholars disagree (sometimes in fundamental ways) about what constitutes legal mobilization, which has resulted in conceptual slippage around how the term is used. This article proposes a more self-conscious approach that will facilitate the aggregation of findings across studies. To do so, it sets forth a systematic conceptualization of legal mobilization and situates it within a typology of uses of the law. It also contextualizes the typology with respect to emerging literatures within social movement and sociolegal scholarship and proposes areas for further research that would benefit from a more rigorous conceptualization of legal mobilization.
Dietary Zn has significant impacts on the growth and development of breeding rams. The objectives of this study were to evaluate the effects of dietary Zn source and concentration on serum Zn concentration, growth performance, wool traits and reproductive performance in rams. Forty-four Targhee rams (14 months; 68 ± 18 kg BW) were used in an 84-day completely randomized design and were fed one of three pelleted dietary treatments: (1) a control without fortified Zn (CON; n = 15; ~1 × NRC); (2) a diet fortified with a Zn amino acid complex (ZnAA; n = 14; ~2 × NRC) and (3) a diet fortified with ZnSO4 (ZnSO4; n = 15; ~2 × NRC). Growth and wool characteristics measured throughout the course of the study were BW, average daily gain (ADG), dry matter intake (DMI), feed efficiency (G : F), longissimus dorsi muscle depth (LMD), back fat (BF), wool staple length (SL) and average fibre diameter (AFD). Blood was collected from each ram at four time periods to quantify serum Zn and testosterone concentrations. Semen was collected 1 to 2 days after the trial was completed. There were no differences in BW (P = 0.45), DMI (P = 0.18), LMD (P = 0.48), BF (P = 0.47) and AFD (P = 0.9) among treatment groups. ZnSO4 had greater (P ≤ 0.03) serum Zn concentrations compared with ZnAA and CON treatments. Rams consuming ZnAA had greater (P ≤ 0.03) ADG than ZnSO4 and CON. There tended to be differences among groups for G : F (P = 0.06), with ZnAA being numerically greater than ZnSO4 and CON. Wool staple length regrowth was greater (P < 0.001) in ZnSO4 and tended to be longer (P = 0.06) in ZnAA treatment group compared with CON. No differences were observed among treatments in scrotal circumference, testosterone, spermatozoa concentration within ram semen, % motility, % live sperm and % sperm abnormalities (P ≥ 0.23). Results indicated beneficial effects of feeding increased Zn concentrations to developing Targhee rams, although Zn source elicited differential responses in performance characteristics measured.
We have observed the G23 field of the Galaxy AndMass Assembly (GAMA) survey using the Australian Square Kilometre Array Pathfinder (ASKAP) in its commissioning phase to validate the performance of the telescope and to characterise the detected galaxy populations. This observation covers ~48 deg2 with synthesised beam of 32.7 arcsec by 17.8 arcsec at 936MHz, and ~39 deg2 with synthesised beam of 15.8 arcsec by 12.0 arcsec at 1320MHz. At both frequencies, the root-mean-square (r.m.s.) noise is ~0.1 mJy/beam. We combine these radio observations with the GAMA galaxy data, which includes spectroscopy of galaxies that are i-band selected with a magnitude limit of 19.2. Wide-field Infrared Survey Explorer (WISE) infrared (IR) photometry is used to determine which galaxies host an active galactic nucleus (AGN). In properties including source counts, mass distributions, and IR versus radio luminosity relation, the ASKAP-detected radio sources behave as expected. Radio galaxies have higher stellar mass and luminosity in IR, optical, and UV than other galaxies. We apply optical and IR AGN diagnostics and find that they disagree for ~30% of the galaxies in our sample. We suggest possible causes for the disagreement. Some cases can be explained by optical extinction of the AGN, but for more than half of the cases we do not find a clear explanation. Radio sources aremore likely (~6%) to have an AGN than radio quiet galaxies (~1%), but the majority of AGN are not detected in radio at this sensitivity.
A national need is to prepare for and respond to accidental or intentional disasters categorized as chemical, biological, radiological, nuclear, or explosive (CBRNE). These incidents require specific subject-matter expertise, yet have commonalities. We identify 7 core elements comprising CBRNE science that require integration for effective preparedness planning and public health and medical response and recovery. These core elements are (1) basic and clinical sciences, (2) modeling and systems management, (3) planning, (4) response and incident management, (5) recovery and resilience, (6) lessons learned, and (7) continuous improvement. A key feature is the ability of relevant subject matter experts to integrate information into response operations. We propose the CBRNE medical operations science support expert as a professional who (1) understands that CBRNE incidents require an integrated systems approach, (2) understands the key functions and contributions of CBRNE science practitioners, (3) helps direct strategic and tactical CBRNE planning and responses through first-hand experience, and (4) provides advice to senior decision-makers managing response activities. Recognition of both CBRNE science as a distinct competency and the establishment of the CBRNE medical operations science support expert informs the public of the enormous progress made, broadcasts opportunities for new talent, and enhances the sophistication and analytic expertise of senior managers planning for and responding to CBRNE incidents.
Shiga toxin-producing Escherichia coli (STEC) infection can cause serious illness including haemolytic uraemic syndrome. The role of socio-economic status (SES) in differential clinical presentation and exposure to potential risk factors amongst STEC cases has not previously been reported in England. We conducted an observational study using a dataset of all STEC cases identified in England, 2010–2015. Odds ratios for clinical characteristics of cases and foodborne, waterborne and environmental risk factors were estimated using logistic regression, stratified by SES, adjusting for baseline demographic factors. Incidence was higher in the highest SES group compared to the lowest (RR 1.54, 95% CI 1.19–2.00). Odds of Accident and Emergency attendance (OR 1.35, 95% CI 1.10–1.75) and hospitalisation (OR 1.71, 95% CI 1.36–2.15) because of illness were higher in the most disadvantaged compared to the least, suggesting potential lower ascertainment of milder cases or delayed care-seeking behaviour in disadvantaged groups. Advantaged individuals were significantly more likely to report salad/fruit/vegetable/herb consumption (OR 1.59, 95% CI 1.16–2.17), non-UK or UK travel (OR 1.76, 95% CI 1.40–2.27; OR 1.85, 95% CI 1.35–2.56) and environmental exposures (walking in a paddock, OR 1.82, 95% CI 1.22–2.70; soil contact, OR 1.52, 95% CI 2.13–1.09) suggesting other unmeasured risks, such as person-to-person transmission, could be more important in the most disadvantaged group.
To describe the relationship between adherence to distinct dietary patterns and nutrition literacy.
We identified distinct dietary patterns using principal covariates regression (PCovR) and principal components analysis (PCA) from the Diet History Questionnaire II. Nutrition literacy was assessed using the Nutrition Literacy Assessment Instrument (NLit). Cross-sectional relationships between dietary pattern adherence and global and domain-specific NLit scores were tested by multiple linear regression. Mean differences in diet pattern adherence among three predefined nutrition literacy performance categories were tested by ANOVA.
Metropolitan Kansas City, USA.
Adults (n 386) with at least one of four diet-related diseases.
Three diet patterns of interest were derived: a PCovR prudent pattern and PCA-derived Western and Mediterranean patterns. After controlling for age, sex, BMI, race, household income, education level and diabetes status, PCovR prudent pattern adherence positively related to global NLit score (P < 0·001, β = 0·36), indicating more intake of prudent diet foods with improved nutrition literacy. Validating the PCovR findings, PCA Western pattern adherence inversely related to global NLit (P = 0·003, β = −0·13) while PCA Mediterranean pattern positively related to global NLit (P = 0·02, β = 0·12). Using predefined cut points, those with poor nutrition literacy consumed more foods associated with the Western diet (fried foods, sugar-sweetened beverages, red meat, processed foods) while those with good nutrition literacy consumed more foods associated with prudent and Mediterranean diets (vegetables, olive oil, nuts).
Nutrition literacy predicted adherence to healthy/unhealthy diet patterns. These findings warrant future research to determine if improving nutrition literacy effectively improves eating patterns.
Introduction: Unplanned return visits to the pediatric emergency department contribute to overcrowding and are used as a quality measure. They have not been well characterized in the literature making it difficult to design interventions to reduce unnecessary return visits. The aim of this study was to understand the reasons for return from the caregiver and physician perspective. Methods: This was a cross sectional survey performed on a convenience sample of unplanned return visits within 72 hours at the IWK Health Centre ED between February and October 2016. Exclusion criteria were: planned return visit, admission during the index visit, or triaged as Canadian Triage and Acuity Score (CTAS) 1 on return visit. Caregiver and physician surveys were developed based on themes identified in published literature. The caregiver was approached to complete a survey after triage and the most responsible physician from the return visit was asked to complete a survey immediately after discharge of the patient from their care. Demographic and clinical data were collected from the ED record from the index and return visits. The primary outcome measure was most important reason for return from the caregiver perspective. Results: There were 461 return visits during the study period and 67 caregivers (14.5%) were included in the final analysis. The response rate for the physician survey was 71%. Caregivers and physicians reported that the most important reason for return was a perceived progression of illness requiring reassessment (79.1% and 66.7% respectively). The majority of caregivers had a family physician on record (95%) but a minority attempted to access their family physician (19.4%) or a walk-in clinic (11.9%). Of those who contacted their family physician only 3 (23%) were offered an appointment within 48 hours and of those who did not contact their family physician 21 (38.2%) stated they would not be able to get an appointment in a reasonable amount of time. Despite this 97% would have trusted their family physician to manage their child's illness. Physicians surveyed stated that the return visit was necessary in 64.6% of cases. Conclusion: Caregivers returned to the ED due to a perceived progression of disease. While some cases may have been appropriate for management in a primary care setting, perceived difficulty with timely access was a barrier. Improved caregiver education about the natural history of disease and the urgency of follow up may reduce return ED visits.
To assess trends of mortality attributable to child and maternal undernutrition (CMU), overweight/obesity and dietary risks of non-communicable diseases (NCD) in sub-Saharan Africa (SSA) using data from the Global Burden of Disease (GBD) Study 2015.
For each risk factor, a systematic review of data was used to compute the exposure level and the effect size. A Bayesian hierarchical meta-regression analysis was used to estimate the exposure level of the risk factors by age, sex, geography and year. The burden of all-cause mortality attributable to CMU, fourteen dietary risk factors (eight diets, five nutrients and fibre intake) and overweight/obesity was estimated.
All age groups and both sexes.
In 2015, CMU, overweight/obesity and dietary risks of NCD accounted for 826204 (95 % uncertainty interval (UI) 737346, 923789), 266768 (95 % UI 189051, 353096) and 558578 (95 % UI 453433, 680197) deaths, respectively, representing 10·3 % (95 % UI 9·1, 11·6 %), 3·3 % (95 % UI 2·4, 4·4 %) and 7·0 % (95 % UI 5·8, 8·3 %) of all-cause mortality. While the age-standardized proportion of all-cause mortality accounted for by CMU decreased by 55·2 % between 1990 and 2015 in SSA, it increased by 63·3 and 17·2 % for overweight/obesity and dietary risks of NCD, respectively.
The increasing burden of diet- and obesity-related diseases and the reduction of mortality attributable to CMU indicate that SSA is undergoing a rapid nutritional transition. To tackle the impact in SSA, interventions and international development agendas should also target dietary risks associated with NCD and overweight/obesity.
Recovery Colleges are opening internationally. The evaluation focus has been on outcomes for Recovery College students who use mental health services. However, benefits may also arise for: staff who attend or co-deliver courses; the mental health and social care service hosting the Recovery College; and wider society. A theory-based change model characterising how Recovery Colleges impact at these higher levels is needed for formal evaluation of their impact, and to inform future Recovery College development. The aim of this study was to develop a stratified theory identifying candidate mechanisms of action and outcomes (impact) for Recovery Colleges at staff, services and societal levels.
Inductive thematic analysis of 44 publications identified in a systematised review was supplemented by collaborative analysis involving a lived experience advisory panel to develop a preliminary theoretical framework. This was refined through semi-structured interviews with 33 Recovery College stakeholders (service user students, peer/non-peer trainers, managers, community partners, clinicians) in three sites in England.
Candidate mechanisms of action and outcomes were identified at staff, services and societal levels. At the staff level, experiencing new relationships may change attitudes and associated professional practice. Identified outcomes for staff included: experiencing and valuing co-production; changed perceptions of service users; and increased passion and job motivation. At the services level, Recovery Colleges often develop somewhat separately from their host system, reducing the reach of the college into the host organisation but allowing development of an alternative culture giving experiential learning opportunities to staff around co-production and the role of a peer workforce. At the societal level, partnering with community-based agencies gave other members of the public opportunities for learning alongside people with mental health problems and enabled community agencies to work with people they might not have otherwise. Recovery Colleges also gave opportunities to beneficially impact on community attitudes.
This study is the first to characterise the mechanisms of action and impact of Recovery Colleges on mental health staff, mental health and social care services, and wider society. The findings suggest that a certain distance is needed in the relationship between the Recovery College and its host organisation if a genuine cultural alternative is to be created. Different strategies are needed depending on what level of impact is intended, and this study can inform decision-making about mechanisms to prioritise. Future research into Recovery Colleges should include contextual evaluation of these higher level impacts, and investigate effectiveness and harms.
Limited evidence exists to guide chest tube management following cardiac surgery in children. We assessed chest tube practice variation by surveying paediatric heart centres to prepare for a multi-site quality improvement project. We summarised management strategies highlighting variability in criteria for chest tube removal between and within centres. This lack of standardisation provides an opportunity for quality improvement.
We study the numbers of involutions and their relation to Frobenius–Schur indicators in the groups
. Our point of view for this study comes from two motivations. The first is the conjecture that a finite simple group
is strongly real (all elements are conjugate to their inverses by an involution) if and only if it is totally orthogonal (all Frobenius–Schur indicators are 1), and we observe this holds for all finite simple groups
other than the groups
even. We prove computationally that for small
this statement indeed holds for these groups by equating their character degree sums with the number of involutions. We also prove a result on a certain twisted indicator for the groups
odd. Our second motivation is to continue the work of Fulman, Guralnick, and Stanton on generating functions and asymptotics for involutions in classical groups. We extend their work by finding generating functions for the numbers of involutions in
, and we use these to compute the asymptotic behavior for the number of involutions in these groups when
is fixed and
An unexpected increase in gastroenteritis cases was reported by healthcare workers on the KwaZulu-Natal Coast, South Africa, January 2017 with >600 cases seen over a 3-week period. A case–control study was conducted to identify the source and risk factors associated with the outbreak so as to recommend control and prevention measures. Record review identified cases and controls and structured-telephonic interviews were conducted to obtain exposure history. Stool specimens were collected from 20 cases along with environmental samples and both screened for enteric pathogens. A total of 126 cases and 62 controls were included in the analysis. The odds of developing gastroenteritis were 6.0 times greater among holiday makers than residents (95% confidence interval (CI) 2.0–17.7). Swimming in the lagoon increased the odds of developing gastroenteritis by 3.3 times (95% CI 1.06–10.38). Lagoon water samples tested positive for norovirus (NoV) GI.6, GII.3 and GII.6, astrovirus and rotavirus. Eleven (55%) stool specimens were positive for NoV with eight genotyped as GI.1 (n = 2), GI.5 (n = 3), GI.6 (n = 2), and GI.7 (n = 1). A reported sewage contamination event impacting the lagoon was the likely source with person-to-person spread perpetuating the outbreak. Restriction to swimming in the lagoon was apparently ineffective at preventing the outbreak, possibly due to inadequate enforcement, communication and signage strategies.
The interaction between droplet dispersion and evaporation in an acetone spray evaporating under ambient conditions is experimentally studied with an aim to understand the physics behind the spatial correlation between the local vapour mass fraction and droplets. The influence of gas-phase turbulence and droplet–gas slip velocity of such correlations is examined, while the focus is on the consequence of droplet clustering on collective evaporation of droplet clouds. Simultaneous and planar measurements of droplet size, velocity and number density, and vapour mass fraction around the droplets, were obtained by combining the interferometric laser imaging for droplet sizing and planar laser induced fluorescence techniques (Sahu et al., Exp. Fluids, vol. 55, 1673, 2014b, pp. 1–21). Comparison with droplet measurements in a non-evaporating water spray under the same flow conditions showed that droplet evaporation leads to higher fluctuations of droplet number density and velocity relative to the respective mean values. While the mean droplet–gas slip velocity was found to be negligibly small, the vaporization Damköhler number (
) was approximately ‘one’, which means the droplet evaporation time and the characteristic time scale of large eddies are of the same order. Thus, the influence of the convective effect on droplet evaporation is not expected to be significant in comparison to the instantaneous fluctuations of slip velocity, which refers to the direct effect of turbulence. An overall linearly increasing trend was observed in the scatter plot of the instantaneous values of droplet number density (
) and vapour mass fraction (
). Accordingly, the correlation coefficient of fluctuations of vapour mass fraction and droplet number density (
) was relatively high (
) implying moderately high correlation. However, considerable spread of the
scatter plot along both coordinates demonstrated the influence on droplet evaporation due to turbulent droplet dispersion, which leads to droplet clustering. The presence of droplet clustering was confirmed by the measurement of spatial correlation coefficient of the fluctuations of droplet number density for different size classes (
) and the radial distribution function (RDF) of the droplets. Also, the tendency of the droplets to form clusters was higher for the acetone spray than the water spray, indicating that droplet evaporation promoted droplet grouping in the spray. The instantaneous group evaporation number (
) was evaluated from the measured length scale of droplet clusters (by the RDF) and the average droplet size and spacing in instantaneous clusters. The mean value of
suggests an internal group evaporation mode of the droplet clouds near the spray centre, while single droplet evaporation prevails near the spray boundary. However, the large fluctuations in the magnitude of instantaneous values of
at all measurement locations implied temporal variations in the mode of droplet cloud evaporation.
This paper revisits the problem of forces on obstacle arrays in combined waves, an in-line steady current and structural dynamic motions. The intended application is the design and re-assessment of dynamically responding offshore platforms. Planar grids of perforated plates are moved in forced motion on three scales through otherwise stationary water. A new analytical wave–current–structure blockage model is developed by building on the existing wave–current blockage model presented by Santo et al. (J. Fluid Mech., vol. 739, 2014b, pp. 143–178) using a similar set of experiments but with forced motion on two scales. The new model, which is an improved Morison relative-velocity formulation, is tested against the experimental data for a range of structural to wave oscillation frequency ratios,
, 2.5 and 3. For relatively small current speed (
) and oscillatory structural velocity (
) compared with the oscillatory wave velocity (
), the drag force time history on grids is well approximated by a summation of the wave drag and the current drag components independently, without a
cross-term, consistent with the previous model. The wave drag component contains an additional
contribution, while the current drag component may or may not contain an additional
contribution depending on
. The measured drag force is observed to be asymmetric in time due to biasing from the mean flow. This is supported by numerical simulation using a porous block as a numerical model of the grids, although the simulated force asymmetry is weaker. All these effects can be sufficiently accounted for in the analytical model. The new model is shown to fit the variation of the experimental forces and force harmonics in time well for a wide range of cases, requiring only calibration of the Morison type drag and inertia coefficients. In contrast, the industry-standard version of the Morison relative-velocity formulation cannot reproduce the variation of the measured force in time, so present practice should be regarded as inadequate for combined steady, low frequency and high frequency motion acting on obstacle arrays.
A model of a High Voltage CMOS (HV-CMOS) Monolithic Active Pixel Sensor (MAPS) has been modelled using Technology Computer Aided Design (TCAD). The model has incorporated both the active region and the on-pixel readout circuits which were comprised of a source follower amplifier and an integrated charge amplifier. The simulation has examined the electrical characteristics and response output of a HV-CMOS MAPS sensor using typical dimensions, levels of doping in the structural layers and bias conditions for this sensor. The performance of two alternate designs of amplifier have been examined as a function of the operating parameters. The response of the sensor to the incidence of Minimum Ionizing Particles (MIPs) at different energies has been included in the model.