Axion particle production in a laser-induced dynamical spacetime

Abstract We consider the dynamics of a charged particle (e.g., an electron) oscillating in a laser field in flat spacetime and describe it in terms of the variable mass metric. By applying Einstein's equivalence principle, we show that, after representing the electron motion in a time-dependent manner, the variable mass metric takes the form of the Friedmann–Lemaître–Robertson–Walker metric. We quantize a pseudo-scalar field in this spacetime and derive the production rate of electrically neutral, spinless particles. We show that this approach can provide an alternative experimental method to axion searches

Admissible evidence in the court of development evaluation? : the impact of CARE's SHOUHARDO Project on child stunting in Bangladesh

Along with the rise of the development effectiveness movement of the last few decades, experimental impact evaluation methods – randomised controlled trials and quasiexperimental techniques – have emerged as a dominant force. While the increased use of these methods has contributed to improved understanding of what works and whether specific projects have been successful, their ‘gold standard’ status threatens to exclude a large body of evidence from the development effectiveness dialogue. In this paper we conduct an evaluation of the impact on child stunting of CARE’s SHOUHARDO project in Bangladesh, the first large-scale project to use the rights-based, livelihoods approach to address malnutrition. In line with calls for a more balanced view of what constitutes rigor and scientific evidence, and for the use of more diversified and holistic methods in impact evaluations, we employ a mixed-methods approach. The results from multiple data sources and methods, including both non-experimental and quasi-experimental, are triangulated to arrive at the conclusions. We find that the project had an extraordinarily large impact on stunting among children 6–24 months old – on the order of a 4.5 percentage point reduction per year. We demonstrate that one reason the project reduced stunting by so much was because, consistent with the rights-based, livelihoods approach, it relied on both direct nutrition interventions and those that addressed underlying structural causes including poor sanitation, poverty, and deeply-entrenched inequalities in power between women and men. These findings have important policy implications given the slow progress in reducing malnutrition globally and that the widely-supported Scaling Up Nutrition initiative aimed at stepping up efforts to do so is in urgent need of guidance on how to integrate structural cause interventions with the direct nutrition interventions that are the initiative’s main focus. The evaluation also adds to the evidence that targeting the poor, rather than employing universal coverage, can help to accelerate reductions in child malnutrition. The paper concludes that, given the valuable policy lessons generated, the experience of the SHOUHARDO project merits solid standing in the knowledge bank of development effectiveness. More broadly, it illustrates how rigorous and informative evaluation of complex, multi-intervention projects can be undertaken even in the absence of the randomisation, nonproject control groups and/or panel data required by the experimental methods. Keywords: development effectiveness; impact evaluation; experimental methods; child malnutrition; Bangladesh

Investigating Master-Slave Architecture for Underwater Wireless Sensor Network.

A significant increase has been observed in the use of Underwater Wireless Sensor Networks (UWSNs) over the last few decades. However, there exist several associated challenges with UWSNs, mainly due to the nodes' mobility, increased propagation delay, limited bandwidth, packet duplication, void holes, and Doppler/multi-path effects. To address these challenges, we propose a protocol named "An Efficient Routing Protocol based on Master-Slave Architecture for Underwater Wireless Sensor Network (ERPMSA-UWSN)" that significantly contributes to optimizing energy consumption and data packet's long-term survival. We adopt an innovative approach based on the master-slave architecture, which results in limiting the forwarders of the data packet by restricting the transmission through master nodes only. In this protocol, we suppress nodes from data packet reception except the master nodes. We perform extensive simulation and demonstrate that our proposed protocol is delay-tolerant and energy-efficient. We achieve an improvement of 13% on energy tax and 4.8% on Packet Delivery Ratio (PDR), over the state-of-the-art protocol

Determination of Histidine and Related Compounds in Rumen Fluid by Liquid Chromatography

A liquid chromatographic procedure was developed for quantitative determination of histidine (His), histidinol (HDL), histamine (HTM), urocanic acid (URA), imidazolepyruvic acid (ImPA), imidazoleacetic acid (ImAA), and imidazolelactic acid (ImLA) in rumen fluid. The method is based on direct injection analysis by UV absorbance detection at 220 nm. The separation was performed under 2 different chromatographic conditions on a LiChrospher 100 NH 2 column. In the first chromatographic system, the mobile phase used for isocratic elution was 67 mM potassium phosphate buffer (monobasic and dibasic) pH 6.45-90% acetonitrile in water (21 + 79); in the second system, an acetonitrile gradient in 63 mM potassium phosphate buffer (monobasic) pH 3.0, obtained by addition of 60 mM phosphoric acid, was used. Analyses of both systems were completed within 32 and 25 min, respectively. The limits of detection of these compounds were (mM): His, 2.8; HDL, 3.7; HTM, 4.0; URA, 0.75; ImPA, 4.7; ImAA, 1.2; and ImLA, 1.3. Recovery of these compounds added to rumen fluid was 97.4-103.0% within a 1-day study and 95.4-99.0% on different day studies. Detectable levels of His were found in the deproteinized rumen fluid of goats, with average concentrations of 16.10, 10.43, 11.14, and 13.62 mM in the rumen fluid collected before the morning feeding and 2, 4, and 6 h after feeding, respectively. HDL, HTM, URA, ImPA, ImAA, and ImLA were not detected in the rumen fluid before and after feeding. Trp, Phe, and Tyr were also identified in the rumen fluid, with average concentrations of 8.25, 29.04, and 12.6 mM, respectively, before the morning feeding

Exposure risk analysis of COVID-19 for a ride-sharing motorbike taxi

A dominant mode of transmission for the respiratory disease COVID-19 is via airborne virus-carrying aerosols. As national lockdowns are lifted and people begin to travel once again, an assessment of the risk associated with different forms of public transportation is required. This paper assesses the risk of transmission in the context of a ride-sharing motorbike taxi—a popular choice of paratransit in South and South-East Asia and Sub-Saharan Africa. Fluid dynamics plays a significant role in understanding the fate of droplets ejected from a susceptible individual during a respiratory event, such as coughing. Numerical simulations are employed here using an Eulerian–Lagrangian approach for particles and the Reynolds-averaged Navier–Stokes method for the background air flow. The driver is assumed to be exhaling virus laden droplets, which are transported toward the passenger by the background flow. A single cough is simulated for particle sizes 1, 10, 50 μm, with motorbike speeds 1, 5, 15 m/s. It has been shown that small and large particles pose different types of risk. Depending on the motorbike speed, large particles may deposit onto the passenger, while smaller particles travel between the riders and may be inhaled by the passenger. To reduce risk of transmission to the passenger, a shield is placed between the riders. The shield not only acts as a barrier to block particles, but also alters the flow field around the riders, pushing particles away from the passenger. The findings of this paper therefore support the addition of a shield potentially making the journey safer

Does Cataract Surgery Alleviate Poverty? Evidence from a Multi-Centre Intervention Study Conducted in Kenya, the Philippines and Bangladesh

BACKGROUND: Poverty and blindness are believed to be intimately linked, but empirical data supporting this purported relationship are sparse. The objective of this study is to assess whether there is a reduction in poverty after cataract surgery among visually impaired cases. METHODOLOGY/PRINCIPAL FINDINGS: A multi-centre intervention study was conducted in three countries (Kenya, Philippines, Bangladesh). Poverty data (household per capita expenditure--PCE, asset ownership and self-rated wealth) were collected from cases aged ≥50 years who were visually impaired due to cataract (visual acuity<6/24 in the better eye) and age-sex matched controls with normal vision. Cases were offered free/subsidised cataract surgery. Approximately one year later participants were re-interviewed about poverty. 466 cases and 436 controls were examined at both baseline and follow-up (Follow up rate: 78% for cases, 81% for controls), of which 263 cases had undergone cataract surgery ("operated cases"). At baseline, operated cases were poorer compared to controls in terms of PCE (Kenya: $22 versus £35 p = 0.02, Bangladesh:$16 vs $24 p = 0.004, Philippines:$24 vs 32 p = 0.0007), assets and self-rated wealth. By follow-up PCE had increased significantly among operated cases in each of the three settings to the level of controls (Kenya: $30 versus £36 p = 0.49, Bangladesh:$23 vs $23 p = 0.20, Philippines:$45 vs $36 p = 0.68). There were smaller increases in self-rated wealth and no changes in assets. Changes in PCE were apparent in different socio-demographic and ocular groups. The largest PCE increases were apparent among the cases that were poorest at baseline. CONCLUSIONS/SIGNIFICANCE: This study showed that cataract surgery can contribute to poverty alleviation, particularly among the most vulnerable members of society. This study highlights the need for increased provision of cataract surgery to poor people and shows that a focus on blindness may help to alleviate poverty and achieve the Millennium Development Goals

Yoda1 and phosphatidylserine exposure in red cells from patients with sickle cell anaemia

Abstract: Phosphatidylserine (PS) exposure is increased in red cells from sickle cell anaemia (SCA) patients. Externalised PS is prothrombotic and attractive to phagocytes and activated endothelial cells and thus contributes to the anaemic and ischaemic complications of SCA. The mechanism of PS exposure remains uncertain but it can follow increased intracellular Ca2+ concentration ([Ca2+]i). Normally, [Ca2+]i is maintained at very low levels but in sickle cells, Ca2+ permeability is increased, especially following deoxygenation and sickling, mediated by a pathway sometimes called Psickle. The molecular identity of Psickle is also unclear but recent work has implicated the mechanosensitive channel, PIEZO1. We used Yoda1, an PIEZO1 agonist, to investigate its role in sickle cells. Yoda1 caused an increase in [Ca2+]i and PS exposure, which was inhibited by its antagonist Dooku1 and the PIEZO1 inhibitor GsMTx4, consistent with functional PIEZO1. However, PS exposure did not necessitate an increase in [Ca2+]i. Two PKC inhibitors were also tested, chelerytherine chloride and calphostin C. Both reduced PS exposure whilst chelerytherine chloride also reduced Yoda1-induced increases in [Ca2+]i. Findings are therefore consistent with the presence of PIEZO1 in sickle cells, able to mediate Ca2+ entry but that PKC was also involved in both Ca2+ entry and PS exposure

The Pesticide Risk Beliefs Inventory: A Quantitative Instrument for the Assessment of Beliefs about Pesticide Risks

Recent media attention has focused on the risks that agricultural pesticides pose to the environment and human health; thus, these topics provide focal areas for scientists and science educators to enhance public understanding of basic toxicology concepts. This study details the development of a quantitative inventory to gauge pesticide risk beliefs. The goal of the inventory was to characterize misconceptions and knowledge gaps, as well as expert-like beliefs, concerning pesticide risk. This study describes the development and field testing of the Pesticide Risk Beliefs Inventory with an important target audience: pesticide educators in a southeastern U.S. state. The 19-item, Likert-type inventory was found to be psychometrically sound with a Cronbach’s alpha of 0.780 and to be a valuable tool in capturing pesticide educators’ beliefs about pesticide risk, assessing beliefs in four key categories. The Pesticide Risk Beliefs Inventory could be useful in exploring beliefs about pesticide risks and in guiding efforts to address misconceptions held by a variety of formal and informal science learners, educators, practitioners, the agricultural labor force, and the general public

Young British Pakistani Muslim women’s involvement in higher education

YesThis article explores the implications for identity through presenting a detailed analysis of how three British Pakistani women narrated their involvement in higher education. The increased participation of British South Asian women in higher education has been hailed a major success story and is said to have enabled them to forge alternative, more empowering gender identities in comparison to previous generations. Drawing on generative narrative interviews conducted with three young women, we explore the under-researched area of Pakistani Muslim women in higher education. The central plotlines for their stories are respectively higher education as an escape from conforming to the ‘good Muslim woman’; becoming an educated mother; and Muslim women can ‘have it all’. Although the women narrated freedom to choose, their stories were complex. Through analysis of personal ‘I’ and social ‘We’ self-narration, we discuss the different ways in which they drew on agency and fashioned it within social and structural constraints of gender, class and religion. Thus higher education is a context that both enables and constrains negotiations of identity