Linear simulations of the cylindrical Richtmyer-Meshkov instability in magnetohydrodynamics

Numerical simulations and analysis indicate that the Richtmyer-Meshkov instability (RMI) is suppressed in ideal magnetohydrodynamics (MHD) in Cartesian slab geometry. Motivated by the presence of hydrodynamic instabilities in inertial confinement fusion and suppression by means of a magnetic field, we investigate the RMI via linear MHD simulations in cylindrical geometry. The physical setup is that of a Chisnell-type converging shock interacting with a density interface with either axial or azimuthal (2D) perturbations. The linear stability is examined in the context of an initial value problem (with a time-varying base state) wherein the linearized ideal MHD equations are solved with an upwind numerical method. Linear simulations in the absence of a magnetic field indicate that RMI growth rate during the early time period is similar to that observed in Cartesian geometry. However, this RMI phase is short-lived and followed by a Rayleigh-Taylor instability phase with an accompanied exponential increase in the perturbation amplitude. We examine several strengths of the magnetic field (characterized by β = 2p/B ) and observe a significant suppression of the instability for β ≤ 4. The suppression of the instability is attributed to the transport of vorticity away from the interface by Alfvén fronts

Choice of speed under compromised Dynamic Message Signs.

This study explores speed choice behavior of travelers under realistic and fabricated Dynamic Message Signs (DMS) content. Using web-based survey information of 4,302 participants collected by Amazon Mechanical Turk in the United States, we develop a set of multivariate latent-based ordered probit models participants. Results show female, African-Americans, drivers with a disability, elderly, and drivers who trust DMS are likely to comply with the fabricated messages. Drivers who comply with traffic regulations, have a good driving record, and live in rural areas, as well as female drivers are likely to slow down under fabricated messages. We highlight that calling or texting, taking picture, and tuning the radio are distracting activities leading drivers to slow down or stop under fictitious scenarios

Moving beyond DNA sequence to improve plant stress responses

Plants offer a habitat for a range of interactions to occur among different stress factors. Epigenetics has become the most promising functional genomics tool, with huge potential for improving plant adaptation to biotic and abiotic stresses. Advances in plant molecular biology have dramatically changed our understanding of the molecular mechanisms that control these interactions, and plant epigenetics has attracted great interest in this context. Accumulating literature substantiates the crucial role of epigenetics in the diversity of plant responses that can be harnessed to accelerate the progress of crop improvement. However, harnessing epigenetics to its full potential will require a thorough understanding of the epigenetic modifications and assessing the functional relevance of these variants. The modern technologies of profiling and engineering plants at genome-wide scale provide new horizons to elucidate how epigenetic modifications occur in plants in response to stress conditions. This review summarizes recent progress on understanding the epigenetic regulation of plant stress responses, methods to detect genome-wide epigenetic modifications, and disentangling their contributions to plant phenotypes from other sources of variations. Key epigenetic mechanisms underlying stress memory are highlighted. Linking plant response with the patterns of epigenetic variations would help devise breeding strategies for improving crop performance under stressed scenarios

Comparison of health-related quality of life after percutaneous coronary intervention and coronary artery bypass surgery

BACKGROUND: Health-related quality of life (HRQOL) evaluation is an important measure of the impact of the disease. As more people with coronary heart disease (CHD) live longer, doctors and researchers want to know how they manage in day to day life. It looked like adults with CHD had a decrease QOL. The aim of this study was to comparison of HRQOL of patients who underwent percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) and to assess its main determinants in the whole sample of coronary artery disease (CAD) patients. METHODS: The study was carried out to estimate HRQOL of 109 patients who underwent invasive coronary revascularization PCI (n = 75) and CABG (n = 34). We applied HRQOL after 6 months and 2 years in both groups and scores were compared. The HRQOL data were obtained using MacNew Heart Disease questionnaire with dimensions emotional, physical and social that estimated. Data entry and analysis were performed by SPSS 16.0. RESULTS: A total MacNew scale in CABG and PCI group in 6 months after treatment were 45.32 ± 13.75 and 53.52 ± 15.63, respectively (P = 0.0100). After 2 years HRQOL mean changed to 51.176 ± 14.80 and 49.55 ± 16.22, respectively, in CABG and PCI group (P = 0.4280). Our results in within-group analysis showed total MacNew scale and its subscales were changed significantly after 2 years in CABG and PCI group�s scores were detected. We found in the whole sample of CAD patients those who had a higher level of income and education and were not either overweight or obese experienced better HRQOL. CONCLUSION: Our results showed that patients who underwent PCI experienced significantly higher HRQOL in 6 months after revascularization but over 24 months follow-up no difference was observed between the two groups. © 2016, Isfahan University of Medical Sciences(IUMS). All rights reserved

Barriopsis iraniana and Phaeobotryon cupressi: two new species of the Botryosphaeriaceae from trees in Iran

Species in the Botryosphaeriaceae are well known as pathogens and saprobes of woody hosts, but little is known about the species that occur in Iran. In a recent survey of this family in Iran two fungi with diplodia-like anamorphs were isolated from various tree hosts. These two fungi were fully characterised in terms of morphology of the anamorphs in culture, and sequences of the ITS1/ITS2 regions of the ribosomal DNA operon and partial sequences of the translation elongation factor 1-α. Phylogenetic analyses placed them within a clade consisting of Barriopsis and Phaeobotryon species, but they were clearly distinct from known species in these genera. Therefore, they are described here as two new species, namely Barriopsis iraniana on Citrus, Mangifera and Olea, and Phaeobotryon cupressi on Cupressus sempervirens

Evaluation of common bean lines for their reaction to the common bacterial blight pathogen

Common bacterial blight (CBB) caused by Xanthomonas axonopodis pv. phaseoli (Xap) is an economically important disease of common beans (Phaseolus vulgaris L.). Since there is no satisfactory chemical control for CBB, the use of resistant cultivars is an important management strategy. In the present study, twenty nine lines and one cultivar of common bean were evaluated for their reaction to Xap under greenhouse and field conditions. The experiments were conducted in randomized complete blocks with three replications. Reaction to Xap was assessed as diseased leaf area (DLA) and the number of spots on the leaves. Data analysis indicated that cultivar Khomein and the Ks21479 and Ks31169 lines were the most susceptible, while Ks51103, BF13607 and BF13608 lines were the most resistant. The data obtained from greenhouse and field experiments were in agreement. None of the evaluated lines and/or cultivars was immune for CBB; however, the three resistant lines were identified for use in cultivation or as sources of resistance to CBB in plant breeding programs

Are welders more at risk of respiratory infections? Findings from a cross-sectional survey and analysis of medical records in shipyard workers: the WELSHIP project

Background Exposure to welding fume increases the risk of pneumococcal infection; whether such susceptibility extends to other respiratory infections is unclear. We report findings from a survey and from medical consultation data for workers in a large shipyard in the Middle East. Methods Between January 2013 and December 2013, we collected cross-sectional information from 529 male workers variously exposed to welding fume. Adjusted ORs for respiratory symptoms (cough, phlegm, wheezing, shortness of breath and 'chest illness') were estimated using multivariable logistic regression. Subsequently, we examined consultation records from 2000 to 2011 for 15 954 workers who had 103 840 consultations for respiratory infections; the associations between respiratory infections and levels of welding exposure were estimated using a count regression model with a negative binomial distribution. Results 13% of surveyed workers reported respiratory symptoms with a higher prevalence in winter, particularly among welders. The adjusted OR in welders versus other manual labourers was 1.72 (95% CI 1.02 to 3.01) overall and 2.31 (1.05 to 5.10) in winter months; no effect was observed in summer. The risk of consultation for respiratory infections was higher in welders than in manual labourers, with an adjusted incidence rate ratio of 1.45 (1.59 to 1.83) overall, 1.47 (1.42 to 1.52) in winter and 1.33 (1.23 to 1.44) in summer (interaction, p<0.001). Conclusions The observation that respiratory symptoms and consultations for respiratory infection in welders are more common in winter may indicate an enhanced vulnerability to a broad range of infections. If confirmed, this would have important implications for the occupational healthcare of a very large, global workforce