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Poor sleep quality among university students is a rising concern as it affects their well-being. Studies have shown an association between physical activity and sleep quality; however, studies in a local context focussing on health sciences undergraduate students are scarce. Thus, a cross-sectional study aiming to assess the prevalence of poor-quality sleep and its association with physical activity was conducted among health sciences students in Kuala Lumpur. A total of 90 undergraduate students aged 19 and above (M=21.9±1.4 years) were recruited from three learning centers by using purposive sampling. A self-administered questionnaire was used to acquire the respondents' socio-demographic information as well as physical activity and sleep assessments. Results showed that 54% of respondents were poor sleepers and nearly half of them were minimally active (43.3%) while only 30% of the respondents were involved in health-enhancing physical activity. Nonetheless, there was no significant association between physical activity level and sleep quality (χ2=1.54, p>0.05). The residences of the respondents significantly contributed to poor sleep quality with those who stayed off-campus having five times the risk of poor sleep quality (OR= 5.084, CI= 1.02-25.42). In conclusion, the high prevalence of poor sleep quality among university students may not be affected by their physical activity; however, their place of residence plays an important role in determining their sleep quality. [ABSTRACT FROM AUTHOR]

We theoretically investigate the charge and spin currents in a three-terminal mesoscopic ring in the presence of a uniform and nonuniform Rashba spin-orbit interaction (SOI). It is shown that a fully spin-polarized charge current and a pure spin current can be generated by tuning the probe voltages and/or the strength of the Rashba SOI. The charge and spin currents oscillate as the strength of the Rashba SOI increases induced by the spin quantum interference. The ratio of probe voltages oscillates synchronously with the pure spin current as the strength of the Rashba SOI increases in a nonuniform Rashba ring, while it remains constant in a uniform Rashba ring. We demonstrate theoretically that a three-terminal uniform Rashba ring can be used as a spin polarizer and/or spin flipper for different spin injections, and a nonuniform Rashba ring could allow us to detect the pure spin current electrically. [ABSTRACT FROM AUTHOR]

Spontaneous perforation of pyometra is an extremely rare emergent gynecologic disease. We report a 73-year-old woman with a spontaneously perforated pyometra presenting with acute abdomen in the emergency department. A dedicated computed tomography examination of the abdominal and pelvic regions revealed the diagnosis. The patient recovered well after surgical intervention and antibiotic treatment. [ABSTRACT FROM AUTHOR]

We investigate theoretically spin-polarized transport in a one-dimensional waveguide structure under spatially periodic electric fields. Strong spin-polarized current can be obtained by tuning the external electric fields. It is interesting to find that the spin-dependent transmissions exhibit gaps at various electron momenta and/or gate lengths, and the gap width increases with increasing the strength of the Rashba effect. The strong spin-polarized current arises from the different transmission gaps of the spin-up and spin-down electrons. [ABSTRACT FROM AUTHOR]

The evolution of luminescence properties and voids formation with respect to annealing temperature in H implanted ZnO was investigated by depth-resolved cathodoluminescence spectroscopy (DRCLS), transmission electron microscopy and secondary ion mass spectrometry (SIMS). The annealing temperature is found to induce noticeable changes to the shape, size and empty volume density of the cavities. DRCLS results also reveal that the green emission is influenced by different annealing temperatures. In particular, the 600 °C anneal produces a strong quenching of the green emission in the implanted region, while after the 800 °C anneal a significant enhancement near the surface is observed. The annealing at 600 °C also results in an uncommon violet emission at ∼3.1 eV that is not observed after a higher annealing temperature. A clear correlation between the violet emission, vacancies and Li is revealed from comparison between the DRCLS intensities and SIMS data. [ABSTRACT FROM AUTHOR]

We investigate the behavior of electric fields originating from adsorbates deposited on a cryogenic atom chip as it is cooled from room temperature to cryogenic temperature. Using Rydberg electromagnetically induced transparency, we measure the field strength versus distance from a 1 mm square of yttrium barium copper oxide (YBCO) patterned onto a yttria stabilized zirconia chip substrate. We find a localized and stable dipole field at room temperature and attribute it to a saturated layer of chemically adsorbed rubidium atoms on the YBCO. As the chip is cooled towards 83 K we observe a change in sign of the electric field as well as a transition from a localized to a delocalized dipole density. We relate these changes to the onset of physisorption on the chip surface when the van der Waals attraction overcomes the thermal desorption mechanisms. Our findings suggest that through careful selection of substrate materials, it may be possible to reduce the electric fields caused by atomic adsorption on chips, opening up experiments to controlled Rydberg-surface coupling schemes. [ABSTRACT FROM AUTHOR]

We investigate theoretically the nonequilibrium (NE) supercurrent flowing in a mesoscopic four-terminal triplet superconductor (TS)/normal metal (N)/triplet superconductor junction, of which the N region is a quantum dot (QD) connected via tunnel barriers to the two TS electrodes and two N electrodes, respectively. We find that both the charge and spin triplet supercurrents could be rapidly suppressed and even reversed by increasing the dc voltage applied across the two N electrodes because of the nonthermal electron energy distribution in the dot, similar to the singlet NE supercurrent in an s-wave superconductor system. The reversed NE triplet supercurrent almost vanishes when the bias equals the TS pair potential as long as the coupling between the N electrodes and the QD is not too weak. This arises from the zero-energy states of the TS Josephson junction making the current-carrying density of states vanish nearly outside the energy gap. It is also shown that in this nonmagnetic system the currents flowing in the N electrodes are spin-polarized and can be modulated by the TS phases owing to the quantum interference effect. [ABSTRACT FROM AUTHOR]

We investigate theoretically a Josephson junction made of two conventional superconductors and a sandwitched zigzag graphene nanoribbon in between. An anomalous atomic-scale 0-π state transition is found in the magnetized or nonmagnetic junction when the zigzag-chain number of the ribbon is odd and only the edge states are involved in transport. The mechanism for the π state is not the usual ferromagnetic exchange splitting that results in a nonzero momentum of the traveling Cooper pair, but the different pseudoparities of quasiparticles at different valleys, which gives rise to an inherent phase shift between the wave numbers of the hole-like and electron-like quasiparticles traveling in the ribbon. When the magnetization increases, the critical Josephson current is enhanced significantly, but the 0-π oscillating period remains nearly unchanged; moreover, the oscillation itself becomes much more regular and outstanding. [ABSTRACT FROM AUTHOR]

We study the spatial and seasonal variability of phytoplankton biomass (as phytoplankton color) in relation to the environmental conditions in the North Sea using data from the Continuous Plankton Recorder survey. By using only environmental fields and location as predictor variables we developed a nonparametric model (generalized additive model) to empirically explore how key environmental factors modulate the spatio-temporal patterns of the seasonal cycle of algal biomass as well as how these relate to the ~1988 North Sea regime shift. Solar radiation, as manifest through changes of sea surface temperature (SST), was a key factor not only in the seasonal cycle but also as a driver of the shift. The pronounced increase in SST and in wind speed after the 1980s resulted in an extension of the season favorable for phytoplankton growth. Nutrients appeared to be unimportant as explanatory variables for the observed spatio-temporal pattern, implying that they were not generally limiting factors. Under the new climatic regime the carrying capacity of the whole system has been increased and the southern North Sea, where the environmental changes have been more pronounced, reached a new maximum. [ABSTRACT FROM AUTHOR]