Strains and pseudo-magnetic fields in circular graphene rings

We demonstrate that circular graphene ring under a shear stress displays strong pseudo-magnetic fields. We calculate the pseudo-magnetic field both from continuum elasticity theory as well as molecular dynamics simulations. Stable wrinkles are induced by shear deformations and lead to enhancement of the pseudo-magnetic field. The strong pseudo-magnetic field found here can be observed by imaging graphene flake at the atomic level e.g. through scanning tunneling microscope.Comment: 11 pages, 8 figures. (Appendixes A and B are added) To appear in Phys. Rev.

Topological electric current from time-dependent elastic deformations in graphene

We show the possibility of inducing an edge charge current by applying time-dependent strain in gapped graphene samples preserving time reversal symmetry. We demonstrate that this edge current has the same origin as the valley Hall response known to exist in the system.Comment: 5 pages, 3 figures, Accepted for publication in Phys. Rev.

Migration health research and policy in south and south-east Asia: mapping the gaps and advancing a collaborative agenda

Migrant health has been the subject of various international agreements in recent years. In parallel, there has been a growth in academic research in this area. However, this increase in focus at international level has not necessarily strengthened the capacity to drive evidence-informed national policy and action in many low- and middle-income countries. The Migration Health South Asia (MiHSA) network aims to challenge some of the barriers to progress in the region. Examples include the bias towards institutions in high-income countries for research funding and agenda-setting and the overall lack of policy-focused research in the region. MiHSA will engage researchers, funders and policy-makers in collectively identifying the most pressing, yet feasible, research questions that could help strengthen migrant and refugee health relevant to the region’s national contexts. In addition, policies and provisions for different migrant populations in the region will be reviewed from the health and rights perspectives, to identify opportunities to strategically align research agendas with the questions being asked by policy-makers. The convergence of migration policy with other areas such as health and labour at global level has created a growing imperative for policy-makers in the region to engage in cross-sector dialogue to align priorities and coordinate responses. Such responses must go beyond narrow public health interventions and embrace rights-based approaches to address the complex patterns of migration in the region, as well as migrants’ precarity, vulnerabilities and agency

Comparative energy, exergy, economic, and environmental (4E) analysis and optimization of two high-temperature Kalina cycles integrated with thermoelectric generators for waste heat recovery from a diesel engine

High-temperature Kalina cycles are among the efficient approaches to recovering waste heat. However, high-temperature Kalina cycles are characterized by complex layouts, lower efficiency, and higher cost. This work aims at conducting a comparative thermodynamic, economic, and environmental assessment of two different configurations of the high-temperature Kalina cycle. Thermoelectric generators, as the simple and developing heat recovery modules for electricity generation, have been embedded in the condensers of the simple High-temperature Kalina cycle, thereby proposing the enhanced thermal performance of the Kalina cycles. A parametric optimization approach was adopted to optimize the net power output and the location of pinch points of condensers. The results indicate that thermoelectric generators can improve the total power capacity of High-temperature Kalina cycles by about 0.29–0.82 kW. Meanwhile, the economic feasibility of this integration has also been investigated. The first enhanced Kalina cycle has energy and exergy efficiencies of 32 % and 63.23 %, respectively. As an economic parameter, the net present values of these cycles are 84.56, 84.77, 86.63, and 86.84 k$ for standard Kalina cycle configuration 1, enhanced Kalina cycle configuration 1, standard Kalina cycle configuration 2, and enhanced Kalina cycle configuration 2, respectively. In addition, the environmental assessment reveals that 15.55, 15.85, 15.54, and 15.84 lit/hr diesel fuel would be saved by operating the waste heat recovery cycles, respectively. Finally, a parametric study has been carried out to study the influences of variations of different parameters on the performance criteria of all four cycles

Risk of Nosocomial Transmission of Nipah Virus in a Bangladesh Hospital

We conducted a seroprevalence study and exposure survey of healthcare workers to assess the risk of nosocomial transmission of Nipah virus during an outbreak in Bangladesh in 2004. No evidence of recent Nipah virus infection was detected despite substantial exposures and minimal use of personal protective equipmen

Lessons learnt from easing COVID-19 restrictions: an analysis of countries and regions in Asia Pacific and Europe.

The COVID-19 pandemic is an unprecedented global crisis. Many countries have implemented restrictions on population movement to slow the spread of severe acute respiratory syndrome coronavirus 2 and prevent health systems from becoming overwhelmed; some have instituted full or partial lockdowns. However, lockdowns and other extreme restrictions cannot be sustained for the long term in the hope that there will be an effective vaccine or treatment for COVID-19. Governments worldwide now face the common challenge of easing lockdowns and restrictions while balancing various health, social, and economic concerns. To facilitate cross-country learning, this Health Policy paper uses an adapted framework to examine the approaches taken by nine high-income countries and regions that have started to ease COVID-19 restrictions: five in the Asia Pacific region (ie, Hong Kong [Special Administrative Region], Japan, New Zealand, Singapore, and South Korea) and four in Europe (ie, Germany, Norway, Spain, and the UK). This comparative analysis presents important lessons to be learnt from the experiences of these countries and regions. Although the future of the virus is unknown at present, countries should continue to share their experiences, shield populations who are at risk, and suppress transmission to save lives

Epidemiological and virological characteristics of influenza viruses circulating in Cambodia from 2009 to 2011

Background: The Cambodian National Influenza Center (NIC) monitored and characterized circulating influenza strains from 2009 to 2011. Methodology/Principal Findings: Sentinel and study sites collected nasopharyngeal specimens for diagnostic detection, virus isolation, antigenic characterization, sequencing and antiviral susceptibility analysis from patients who fulfilled case definitions for influenza-like illness, acute lower respiratory infections and event-based surveillance. Each year in Cambodia, influenza viruses were detected mainly from June to November, during the rainy season. Antigenic analysis show that A/H1N1pdm09 isolates belonged to the A/California/7/2009-like group. Circulating A/H3N2 strains were A/Brisbane/10/2007-like in 2009 before drifting to A/Perth/16/2009-like in 2010 and 2011. The Cambodian influenza B isolates from 2009 to 2011 all belonged to the B/Victoria lineage represented by the vaccine strains B/Brisbane/60/2008 and B/Malaysia/2506/2004. Sequences of the M2 gene obtained from representative 2009–2011 A/H3N2 and A/H1N1pdm09 strains all contained the S31N mutation associated with adamantanes resistance except for one A/H1N1pdm09 strain isolated in 2011 that lacked this mutation. No reduction in the susceptibility to neuraminidase inhibitors was observed among the influenza viruses circulating from 2009 to 2011. Phylogenetic analysis revealed that A/H3N2 strains clustered each year to a distinct group while most A/H1N1pdm09 isolates belonged to the S203T clade. Conclusions/Significance: In Cambodia, from 2009 to 2011, influenza activity occurred throughout the year with peak seasonality during the rainy season from June to November. Seasonal influenza epidemics were due to multiple genetically distinct viruses, even though all of the isolates were antigenically similar to the reference vaccine strains. The drug susceptibility profile of Cambodian influenza strains revealed that neuraminidase inhibitors would be the drug of choice for influenza treatment and chemoprophylaxis in Cambodia, as adamantanes are no longer expected to be effective

Influenza activity in Cambodia during 2006-2008

<p>Abstract</p> <p>Background</p> <p>There is little information about influenza disease among the Cambodian population. To better understand the dynamics of influenza in Cambodia, the Cambodian National Influenza Center (NIC) was established in August 2006. To continuously monitor influenza activity, a hospital based sentinel surveillance system for ILI (influenza like illness) with a weekly reporting and sampling scheme was established in five sites in 2006. In addition, hospital based surveillance of acute lower respiratory infection (ALRI) cases was established in 2 sites.</p> <p>Methods</p> <p>The sentinel sites collect weekly epidemiological data on ILI patients fulfilling the case definition, and take naso-pharyngeal specimens from a defined number of cases per week. The samples are tested in the Virology Unit at the Institut Pasteur in Phnom Penh. From each sample viral RNA was extracted and amplified by a multiplex RT-PCR detecting simultaneously influenza A and influenza B virus. Influenza A viruses were then subtyped and analyzed by hemagglutination inhibition assay. Samples collected by the ALRI system were tested with the same approach.</p> <p>Results</p> <p>From 2006 to 2008, influenza circulation was observed mainly from June to December, with a clear seasonal peak in October shown in the data from 2008.</p> <p>Conclusion</p> <p>Influenza activity in Cambodia occurred during the rainy season, from June to December, and ended before the cool season (extending usually from December to February). Although Cambodia is a tropical country geographically located in the northern hemisphere, influenza activity has a southern hemisphere transmission pattern. Together with the antigenic analysis of the circulating strains, it is now possible to give better influenza vaccination recommendation for Cambodia.</p