Impact of pulsed plasma beam on the thermal erosion and the surface structure of graphite

Among materials prospective as plasmaface materials for first wall of fusion reactor a priority is given to the materials with low atomic number, high threshold for physical sputtering, high thermal conductivity, low chemical activity to hydrogen, high thermal resistance and melting point. According to modern point of view, preferred plasma-face materials for tokamaks and future Generation IV reactors should be based on the carbon, beryllium and tungsten. Tungsten is one of the most promising materials for protection of tokamaks diverter plates

Impact of pulsed plasma beam on the thermal erosion and the surface structure of graphite

Among materials prospective as plasmaface materials for first wall of fusion reactor a priority is given to the materials with low atomic number, high threshold for physical sputtering, high thermal conductivity, low chemical activity to hydrogen, high thermal resistance and melting point. According to modern point of view, preferred plasma-face materials for tokamaks and future Generation IV reactors should be based on the carbon, beryllium and tungsten. Tungsten is one of the most promising materials for protection of tokamaks diverter plates

Synergistic effect of energy drinks and overweight/obesity on cardiac autonomic testing using the Valsalva maneuver in university students

BACKGROUND: Obesity and caffeine consumption may lead to autonomic disturbances that can result in a wide range of cardiovascular disorders. OBJECTIVES: To determine autonomic disturbances produced by the synergistic effects of overweight or obesity (OW/OB) and energy drinks. DESIGN: Cross-sectional, analytical. SETTING: Physiology department at a university in Saudi Arabia. SUBJECTS AND METHODS: University students, 18–22 years of age, of normal weight (NW) and OW/OB were recruited by convenience sampling. Autonomic testing by the Valsalva ratio (VR) along with systolic and diastolic blood pressure, pulse pressure, and mean arterial blood pressure were measured at baseline (0 minute) and 60 minutes after energy drink consumption. MAIN OUTCOME MEASURE(S): Autonomic disturbance, hemodynamic changes. RESULTS: In 50 (27 males and 23 females) subjects, 21 NW and 29 OW/OB, a significant decrease in VR was observed in OW/OB subjects and in NW and OW/OB females at 60 minutes after energy drink consumption. Values of systolic and diastolic blood pressure, pulse pressure and mean arterial blood pressure were also significantly higher in OW/OB and in females as compared to NW and males. BMI was negatively correlated with VR and diastolic blood pressure at 60 minutes. CONCLUSION: Obesity and energy drinks alter autonomic functions. In some individuals, OW/OB may augment these effects. LIMITATIONS: Due to time and resource restraints, only the acute effects of energy drinks were examined

A Rare Devastating Complication of Lasik: Bilateral Fungal Keratitis

Purpose. To report an unusual case of severe bilateral fungal keratitis following laser in situ keratomileusis (LASIK). Method. A 48-year-old man developed bilateral diffuse corneal infiltration two weeks after LASIK. The corneal scrapings revealed fungal filaments but cultures were negative. Results. The corneal ulceration was improved on the left eye whereas spontaneous perforation occurred and finally evisceration was needed on the right eye despite topical and systemic antifungal treatment. Conclusions. Fungal keratitis, especially with bilateral involvement, is a very rare and serious complication of LASIK surgery. Clinical suspicion is crucial because most of fungal keratitis are misdiagnosed as bacterial keratitis and can lead serious visual results, even eye loss

Influence of interdiffusion on multilayered gradient refractive index (GRIN) lens materials

a b s t r a c t The interdiffusion of two materials used to fabricate polymeric gradient refractive index (GRIN) lenses was examined by varying contact time during multilayer films co-extrusion composed of alternating poly(methylmethacrylate) (PMMA) and poly(styrene-co-acrylonitrile) with 17 mol% acrylonitrile (SAN17). The model applied successfully described their interdiffusion, and a reasonable mutual diffusion coefficient of 7.0 Â 10 À13 m 2 /s was determined. Atomic force microscopy confirmed good agreement between modeled profiles and actual layer structure, and optical properties were investigated. Films with contact times of 160 s exhibited multiple refractive indices, while films with longer contact times, showed single refractive indices that followed an additive line. Though a single additive value requires layers a quarter-wavelength of light, these films exhibit such behavior with thicknesses 5Â greater than expected, though layer resolution is still present. Using the model profiles, it was determined that only a 1% reduction in material purity is required to reduce the effective layer thickness

Effect of energy drink consumption on baroreceptor sensitivity in young normal weight and overweight/obese males

Objectives: There is lack of evidence exploring sympathetic effect by baroreceptor sensitivity in obese consuming energy drink. The purpose of this study was to investigate the acute effect of energy drink on individuals baroreceptor sensitivity in young healthy normal weight and overweight/obese males. Methods: This cross-sectional study was performed in the Department of Physiology, Imam Abdulrahman Bin Faisal University, Kingdom of Saudi Arabia. After getting ethical approval, 25 male participants were recruited by convenient sampling and informed consent was obtained. Participants were grouped into normal weight and overweight/obese on basis of body mass index. Finger arterial blood pressure was recorded with Finometer® at baseline, 30min and 60 minutes in the post-energy drink period and baroreceptor sensitivity was calculated. As data was not normally distributed it was log transformed. Results: The baseline baroreceptor sensitivity was lower (P<0.05) in overweight/obese compared to normal weight participants. Baroreceptor sensitivity reduced significantly (P<0.05) at 60 minutes after energy drink consumption in the whole cohort of both normal weight and overweight/obese. Baroreceptor sensitivity remained lower in overweight/obese compared to normal weight at 60min but the difference was not significant. Conclusion: Consumption of energy drink acutely reduced baroreceptor sensitivity in both normal weight and obese young healthy males with an earlier onset of effect in overweight/obese indicating enhanced sympathetic activity. Energy drinks consumption could place the obese in a more vulnerable state to hypertension and arrhythmia

Human west nile virus disease outbreak in Pakistan, 2015–2016

Like most of the world, Pakistan has seen an increase in mosquito-transmitted diseases in recent years. The magnitude and distribution of these diseases are poorly understood as Pakistan does not have a nation-wide system for reporting disease. A cross-sectional study to determine which flaviviruses were causing of arboviral disease in Pakistan was instituted. West Nile virus (WNV) is a cause of seasonal fever with neurotropic findings in countries that share borders with Pakistan. Here, we describe the active and persistent circulation of WNV in humans in the southern region of Pakistan. This is the first report of WNV causing neurological disease in human patients in this country. Of 997 enrolled patients presenting with clinical features suggestive of arboviral disease, 105 were positive for WNV IgM antibodies, and 71 of these patients possessed WNV-specific neutralizing antibodies. Cross-reactivity of WNV IgM antibodies with Japanese encephalitis virus(JEV) occurred in 75 of these 105 patients. WNV co-infections with Dengue viruses were not a contributing factor for the severity of disease. Nor did prior exposure to dengue virus contribute to incidence of neurological involvement in WNV-infected patients. Patients with WNV infections were more likely to present with altered mental status, seizures, and reduced Glasgow Coma scores when compared with JEV-infected patients. Human WNV cases and vector numbers exhibited a temporal correlation with climate

Spectroscopy of the transition-rate matrix for molecular junctions: dynamics in the Franck-Condon regime

The quantum master equation applied to electronic transport through nanoscopic devices provides information not only on the stationary state but also on the dynamics. The dynamics is characterized by the eigenvalues of the transition-rate matrix, or generator, of the master equation. We propose to use the spectrum of these eigenvalues as a tool for the study of nanoscopic transport. We illustrate this idea by analyzing a molecular quantum dot with an electronic orbital coupled to a vibrational mode, which shows the Franck-Condon blockade if the coupling is strong. Our approach provides complementary information compared to the study of observables in the stationary state.Comment: 13 pages, 13 figure