Non-axisymmetric Magnetorotational Instabilities in Cylindrical Taylor-Couette Flow

We study the stability of cylindrical Taylor-Couette flow in the presence of azimuthal magnetic fields, and show that one obtains non-axisymmetric magnetorotational instabilities, having azimuthal wavenumber m=1. For Omega_o/Omega_i only slightly greater than the Rayleigh value (r_i/r_o)^2, the critical Reynolds and Hartmann numbers are Re_c ~ 10^3 and Ha_c ~ 10^2, independent of the magnetic Prandtl number Pm. These values are sufficiently small that it should be possible to obtain these instabilities in the PROMISE experimental facility.Comment: final version as accepted by Phys Rev Let

Level of awareness, attitude and perception about human papilloma virus vaccine among University of Mauritius students

The rising number of HPV infections is of global concern. Hence, this study helps to assess awareness, attitude, and perception regarding the HPV vaccine among young people of various fields and both genders as they are equally susceptible to the infection. These are essential to prevent complications like cervical cancer. A cross- sectional quantitative study was carried out, involving online questionnaires in English, French and Kreol Morisien languages distributed on various student platforms. There was randomization of data. Participation was entirely voluntary. 58% of respondents have heard of HPV infection. Female gender and Health Sciences students were more aware of HPV infection. 68.5% of respondents reported that they think the vaccine is safe and 77 % of participants are willing to be vaccinated against HPV post the survey. Awareness about HPV infection and vaccines is relatively high among girls and Health Sciences students. Public health efforts to educate students on HPV and cervical cancer should be strengthened to help curb the rising incidence in Mauritius. Therefore, stakeholders should be proactive to address vaccine hesitancy and increase awareness of vaccine safety. Boys should also be included in the National Immunization Programme to enhance the primary prevention of HPV infection. (Afr J Reprod Health 2022; 26[12]: 41-48). Le nombre croissant d'infections au VPH est une préoccupation mondiale. Par conséquent, cette étude aide à évaluer la sensibilisation, l'attitude et la perception concernant le vaccin contre le VPH chez les jeunes de divers domaines et des deux sexes, car ils sont également sensibles à l'infection. Ceux-ci sont essentiels pour prévenir les complications comme le cancer du col de l'utérus. Une étude quantitative transversale a été réalisée, impliquant des questionnaires en ligne en langues anglaise, française et créole morisienne distribués sur différentes plateformes étudiantes. Il y a eu une randomisation des données. La participation était entièrement volontaire. 58% des répondants ont entendu parler de l'infection au VPH. Les étudiantes et étudiants en sciences de la santé étaient plus conscients de l'infection au VPH. 68,5 % des répondants ont déclaré qu'ils pensaient que le vaccin était sûr et 77 % des participants étaient disposés à se faire vacciner contre le VPH après l'enquête. La sensibilisation à l'infection au VPH et aux vaccins est relativement élevée chez les filles et les étudiants en sciences de la santé. Les efforts de santé publique pour éduquer les étudiants sur le VPH et le cancer du col de l'utérus devraient être renforcés pour aider à freiner l'augmentation de l'incidence à Maurice. Par conséquent, les parties prenantes doivent être proactives pour lutter contre la réticence à la vaccination et accroître la sensibilisation à la sécurité des vaccins. Les garçons devraient également être inclus dans le programme national de vaccination afin d'améliorer la prévention primaire de l'infection par le VPH. (Afr J Reprod Health 2022; 26[12]: 41-48)

Workshop Report: Is Mathematics Inclusive or Exclusive? Putting colour, culture and context in the curriculum

The workshop, “Is Mathematics Inclusive or Exclusive?  Putting colour, culture and context in the curriculum†was held in January 2022 with the goal of supporting a national discussion around race and the mathematics curriculum in UK higher education.  This report summarises the talks and discussion, which related to racial and ethnic inclusion in the history of mathematics, race and culture in mathematics education, and ethics and inclusion in mathematics.   It concludes with a proposal of actions for individuals, departments and institutions and the mathematics community in UK higher education to move work on this area forward

Single Platinum Atoms Electrocatalysts: Oxygen Reduction and Hydrogen Oxidation Reactions

Atomically dispersed catalyst consisting of Pt atoms arranged in a c(2 × 2) array on RuO2(110) substrate was prepared. A large interatomic distance of Pt atoms in a c(2 × 2) phase precludes the reactants to interact with more than one Pt atoms. A strong bond of Pt atoms with RuO2 prevents agglomeration of Pt atoms to form 2D-islands or 3D-clusters. Activities of single Pt atom catalyst for the oxygen reduction and hydrogen oxidation reactions were determined and compared with those of bulk Pt. It has lower catalytic activity for the oxygen reduction reaction and similar activity for hydrogen oxidation reaction compared to Pt(111). This was explained by a large calculated up-shift of the d-band center of Pt atoms and larger Pt-Pt interatomic distance than that of Pt(111). This information is of considerable interest for further development of electrocatalysis. This work is licensed under a Creative Commons Attribution 4.0 International License

Adverse clinical outcomes associated with a low dose and a high dose of aspirin following percutaneous coronary intervention: a systematic review and meta-analysis

BACKGROUND: Guidelines from the American Heart Association/American College of Cardiology recommend a higher dosage of aspirin daily following Percutaneous Coronary Intervention (PCI), whereas guidelines from the European Society of Cardiology recommend a lower dosage. This study aimed to compare the adverse clinical outcomes associated with a low dose and a high dose of aspirin following PCI. METHODS: Electronic databases were searched for studies comparing a low dose with a high dose aspirin following PCI. Adverse clinical outcomes were considered as the endpoints in this study. We calculated Odds Ratios (OR) with 95 % Confidence Intervals (CIs) for categorical variables. The pooled analyses were performed with RevMan 5.3 software. RESULTS: A total number of 25,083 patients were included. Results from this analysis showed that the combination of Cardiovascular (CV) death/Myocardial Infarction (MI) or stroke was not significantly different between a low and high dose of aspirin with OR: 1.08, 95 % CI: 0.98–1.18; P = 0.11. Mortality and MI were also not significantly different between these two treatment regimens following PCI with OR: 0.95, 95 % CI: 0.74–1.23; P = 0.71 and OR: 1.17, 95 % CI: 0.97–1.41; P = 0.09 respectively. However, a high dose of aspirin was associated with a significantly higher rate of Major Adverse Cardiac Events (MACEs) with OR: 1.20, 95 % CI: 1.02–1.41; P = 0.03. Thrombolysis In Myocardial Infarction (TIMI) defined minor bleeding was also significantly higher with a high dose aspirin with OR: 1.22, 95 % CI: 1.02–1.47; P = 0.03. When Stent thrombosis (ST) was compared, no significant difference was found with OR: 1.28, 95 % CI: 0.59–2.58; P = 0.53. Even if TIMI defined major bleeding favored a low dose of aspirin, with OR: 1.42, 95 % CI: 0.95–2.13; P = 0.09, or even if major bleeding was insignificantly higher with a high dose aspirin, with OR: 1.78, 95 % CI: 1.01–3.13; P = 0.05; I(2) = 94 %, higher levels of heterogeneity observed in these subgroups could not be considered significant to any extent. CONCLUSION: According to the results of this analysis, a high dose of aspirin following PCI was not associated with any significantly higher rate of CV death/MI/stroke, mortality or MI. However, MACEs significantly favored a low dose of aspirin. In addition, TIMI defined minor bleeding was significantly higher with a high dose of aspirin whereas the results for the major bleeding outcomes were not statistically significant. However, due to limited data availability and since the subgroups analyzing major bleeding were highly heterogeneous, further studies are recommended to completely solve this issue

A systematic review of the effects of prolonged cow-calf contact on behavior, welfare, and productivity

Separation of calves from cows within hours or days of birth is common on dairy farms. Stakeholders have conflicting perspectives on whether this is harmful or beneficial for the animals’ welfare and production. Our objective was to critically evaluate the scientific evidence for both acute and long-term effects of early separation versus an extended period of cow-calf contact. The outcomes investigated were the behavior, welfare (excluding physical health) and performance (milk yield and growth, respectively) of dairy cows and calves. Primary research papers were found through targeted Web of Science searches, the reference lists of recent reviews for each topic, and the reference lists of papers identified from these sources. Studies were included if they were published in English, the full text was accessible, and they compared treatments with and without contact between dairy cows and calves for a specified period. Early separation (within 24 h post-partum) was found to reduce acute distress responses of cows and calves. However, longer cow-calf contact typically had positive longer-term effects on calves, promoting more normal social behavior, reducing abnormal behavior and sometimes reducing responses to stressors. In terms of productivity, allowing cows to nurse calves generally decreased the volume of milk available for sale during the nursing period, but there was no consistent evidence of reduced milk production over a longer period. Allowing a prolonged period of nursing increased calf weight gains during the milk-feeding period. In summary, extended cow-calf contact aggravates the acute distress responses and reduces the amount of saleable milk while the calves are suckling, but can have positive effects on behaviors relevant to welfare in the longer term and benefit calf growth. The strength of these conclusions is limited, however, given that relatively few studies address most of these effects and that experimental design including timing of contact and observations are often inconsistent across studies. Few studies presented indicators of long-term welfare effects other than abnormal and social behavior of the calves

Bleeding outcomes associated with rivaroxaban and dabigatran in patients treated for atrial fibrillation: a systematic review and meta-analysis

Abstract Background Warfarin is commonly used as a secondary prevention of stroke in patients with atrial fibrillation (AF). However, limitations have been observed even with the use of this medication. Recently, several newer direct oral anticoagulants (DOACs) have been approved for use by the food and drug administrations. Unfortunately, these newer drugs have seldom been compared directly with each other. Therefore, this study aimed to compare the bleeding events associated with rivaroxaban and dabigatran in patients treated for non-valvular AF. Methods EMBASE, Medline (National Library of Medicine) and the Cochrane Central Registry of Controlled Trials were searched for studies comparing rivaroxaban with dabigatran using the terms \u2018rivaroxaban, dabigatran and atrial fibrillation\u2019. Primary endpoints were: any bleeding outcomes, intracranial bleeding and gastro-intestinal (GI) bleeding. Secondary outcomes included stroke/systemic embolism (SE)/transient ischemic attack (TIA), venous thromboembolism and mortality. Odds ratios (OR) with 95% confidence intervals (CIs) were calculated. The pooled analyses were carried out with RevMan 5.3 software. All the authors had full access to the data and approved the manuscript as written. Results A total number of 4895 patients were included. This analysis showed that rivaroxaban was not associated with a significantly higher bleeding event when compared to dabigatran (OR: 1.28, 95% CI: 0.95\u20131.72; P \u2009=\u20090.11). GI bleeding was similarly manifested between these two DOACs (OR: 0.98, 95% CI: 0.43\u20132.25; P \u2009=\u20090.97). Even if intracranial bleeding was higher with the use of rivaroxaban, (OR: 2.18, 95% CI: 0.51\u20139.25; P \u2009=\u20090.29), the result was not statistically significant. Moreover, stroke/SE/TIA and venous thromboembolism were also not significantly different (OR: 0.81, 95% CI: 0.53\u20131.23; P \u2009=\u20090.32) and (OR: 2.06, 95% CI: 0.73\u20135.82; P \u2009=\u20090.17) respectively. However, even if mortality favored dabigatran (OR: 1.42, 95% CI: 0.99\u20132.06; P \u2009=\u20090.06), this result only approached statistical significance. Conclusion Head to head comparison showed that rivaroxaban was not associated with significantly higher bleeding events compared to dabigatran. Intracranial bleeding, GI bleeding, stroke/SE/TIA, venous thromboembolism and mortality were also not significantly different between these two DOACs. However, due to the ..

Clinical Study Effectiveness of Green Tea in a Randomized Human Cohort: Relevance to Diabetes and Its Complications

Epidemiological studies have argued that green tea could mitigate diabetes and its complications. This study investigated the phytophenolic profile of Mauritian green tea and its antioxidant propensity. The effect of green tea on the risk factors: waist-hip ratio, glucose level, arterial pressure, antioxidant status, and alanine aminotransferase (ALT) in prediabetics was assessed. The experimental group consumed 3 cups of green tea daily for 14 weeks followed by a 2-week washout period. The control group followed a water regimen. Green tea contained high level of phenolics related to its antioxidant power. Green tea suppressed waisthip ratio of women from a significant increase and suppressed mean arterial pressure of men and women from a significant decrease after week 14. It reduced ALT level in women by 13.0% ( < 0.1) while increasing the antioxidant potential of men and women sera by 2.7% ( < 0.1) and 5.1% ( < 0.1). The study timescale may have been too short to enable demonstration of effects on fasting plasma glucose and HbA1c outcomes. Green tea regimen could form part of a healthy lifestyle that might ameliorate features of metabolic syndrome and subsequent risks for diabetes and its complications. This trial is registered with ClinicalTrials.gov NCT01248143

Surface and internal tides above sea-floor topography

Waves of long spatial scale (meaning wavelengths of hundreds or thousands of kilometres) and long time scale (meaning periods of hours or days) are important in a range of dynamical phenomena in the ocean. For example, these waves are fundamental to the dynamics of ocean tides, which are the focus of this study. Here we are concerned with both barotropic waves and internal waves, and the forcing of internal waves of tidal frequency (internal tides) by barotropic tides. After an introduction to the background and physical significance of this subject, the governing equations for long barotropic linear waves are set out and the underlying assumptions are discussed. We then turn to the issue of coastally-trapped barotropic waves, and review some simple solutions for the three main classes of such waves (the Kelvin wave, edge waves, and topographic Rossby waves). Detailed solutions are derived for these waves above a simple step topography, based upon an analytically derived dispersion relation, and these solutions are compared with numerical solutions above a smooth topography. A detailed solution is also derived for a family of topographic Rossby waves above a smooth slope in an unbounded domain, and the frequencies of these waves are shown to be in good agreement with the frequencies determined by numerical solutions with a coastline. Throughout, there is a focus on waves of tidal period. A simple solution of internal tide generation is also presented, in a two-layer fluid with a step topography (and no background rotation or coastline). Explicit analytical expressions are derived for the outgoing internal wave energy fluxes in this model, and are compared with estimates of energy fluxes in the real ocean