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The Arizona Department of Health Services identified unusually high levels of influenza activity and severe complications during the 2015–2016 influenza season leading to concerns about potential increased disease severity compared with prior seasons. We estimated state-level burden and severity to compare across three seasons using multiple data sources for community-level illness, hospitalisation and death. Severity ratios were calculated as the number of hospitalisations or deaths per community case. Community influenza-like illness rates, hospitalisation rates and mortality rates in 2015–2016 were higher than the previous two seasons. However, ratios of severe disease to community illness were similar. Arizona experienced overall increased disease burden in 2015–2016, but not increased severity compared with prior seasons. Timely estimates of state-specific burden and severity are potentially feasible and may provide important information during seemingly unusual influenza seasons or pandemic situations.
A high proportion of patients with remitted major depressive disorder (MDD) will experience recurring episodes, whilst some develop resilience and remain in recovery. The neural basis of resilience to recurrence is elusive. Abnormal resting-state connectivity of the subgenual cingulate cortex (sgACC) was previously found in cross-sectional studies of MDD, suggesting its potential pathophysiological importance. The current study aimed to investigate whether resting-state connectivity to a left sgACC seed region distinguishes resilient patients from those developing recurring episodes.
A total of 47 medication-free remitted MDD patients and 38 healthy controls underwent resting-state functional magnetic resonance imaging (fMRI) at baseline. Over 14 months, 30 patients remained resilient whilst 17 experienced a recurring episode.
Attenuated interhemispheric left-to-right sgACC connectivity distinguished the resilient from the recurring-episode and control groups and was not correlated with residual depressive symptoms.
The current study revealed a neural signature of resilience to recurrence in MDD and thereby elucidates the role of compensatory adaptation in sgACC networks.
The solar convection zone exhibits a differential rotation with radius and latitude that poses major theoretical challenges. Helioseismology has revealed that a smoothly varying pattern of decreasing angular velocity Ω with latitude long evident at the surface largely prints through much of the convection zone, encountering a region of strong shear called the tachocline at its base, below which the radiative interior is nearly in uniform solid body rotation. Helioseismic observations with MDI on SOHO and with GONG have also led to the detection of significant variations in Ω with 1.3 yr period in the vicinity of the tachocline. There is another shearing layer just below the solar surface, and that region exhibits propagating bands of zonal flow. Such rich dynamical behavior requires theoretical explanations, some of which are beginning to emerge from detailed 3-D simulations of turbulent convection in rotating spherical shells. We discuss some of the properties exhibited by such numerical models. Although these simulations are highly simplified representations of much of the complex physics occurring within the convection zone, they are providing a very promising path for understanding the solar differential rotation and its temporal variations.
A radiochemical 71Ga−71 Ge experiment to determine the integral flux of neutrinos from the sun has been constructed at the Baksan Neutrino Observatory in the USSR. Measurements have begun with 30 tonnes of gallium. The experiment is being expanded with the addition of another 30 tonnes. The motivation, experimental procedures, and present status of this experiment are presented.
Gamma-ray burst host galaxies are deficient in molecular gas, and show anomalous metal-poor regions close to GRB positions. Using recent Australia Telescope Compact Array (ATCA) Hi observations we show that they have substantial atomic gas reservoirs. This suggests that star formation in these galaxies may be fuelled by recent inflow of metal-poor atomic gas. While this process is debated, it can happen in low-metallicity gas near the onset of star formation because gas cooling (necessary for star formation) is faster than the Hi-to-H2 conversion.
In recent years, there has been much interest in modelling graphene nanoribbons as they have great potential for use in molecular electronics. We have employed the NEGF formalism to determine the conductivity of graphene nanoribbons in various configurations. The electronic structure calculations were performed within the framework of the Extended Huckel Approximation. Both zigzag and armchair nanoribbons have been considered. In addition, we have also computed the transmission and conductance using the non-equilibrium Greens function formalism for these structures. We also investigated the effect of defects by considering a zigzag nanoribbon with six carbon atoms removed. Finally, the effect of embedding boron nitride aromatic molecules in the nanoribbon has been considered. The results of our calculations are compared with that obtained from recent work carried out using tight-binding model Hamiltonians.
We report on follow-up observations of 20 short-duration gamma-ray bursts
(T90 < 2s) performed in
with the Gamma-Ray Burst Optical Near-Infrared Detector (GROND) between mid-2007 and the
end of 2010. This is the most homogeneous and comprehensive data set on GRB afterglow
observations of short bursts. In three cases, GROND was on target within less than 10 min
after the trigger, leading to the discovery of the afterglow of GRB 081226A and its faint
underlying host galaxy. In addition, GROND was able to image the optical afterglow and
follow the light curve evolution in five further cases: GRBs 090305, 090426, 090510,
090927, and 100117A. Three of the aforementioned six bursts with optical light curves show
a break: GRBs 090426 and 090510 as well as GRB 090305. For GRB 090927, no break is seen in
the optical/X-ray light curve until about 150 ks/600 ks after the burst. A decay slope of
the optical afterglow of GRB 100117A could be measured. Using these data supplemented by
about ten events taken from the literature, we compare the jet half-opening angles of long
and short bursts. We find a tentative evidence that short bursts have wider opening angles
than long bursts. However, the statistics are still very poor and follow-up observations
of these events are therefore very important to gain as much observational data as
The incidence of papillary thyroid cancer is rising, with an increase in the number of microcarcinomas being discovered. There is controversy in the literature regarding the optimal management of these tumours. This study aimed to review our institution's experience with the presentation and management of papillary thyroid microcarcinoma.
Retrospective analysis from the Sydney Head and Neck Cancer Institute, from 1987 to 2009.
A total of 228 patients were analysed. Papillary thyroid microcarcinomas were discovered incidentally in 116 (50.9 per cent) patients and non-incidentally in the remaining 112 (49.1 per cent) patients. Amongst the non-incidental group, 11.6 per cent of patients presented with lateral cervical lymph node involvement. Non-incidental microcarcinomas were significantly associated with younger age (<45 years) (p = 0.007) and larger tumours (5–10 mm) (p < 0.001). Only four patients in the incidental group suffered recurrent disease (locoregional). No patient developed distant metastatic disease or died during follow up.
Papillary thyroid microcarcinomas present both incidentally and non-incidentally, with equal prevalence. Non-incidental tumours not infrequently present with cervical lymph node disease. The patient outcome is generally excellent.
The creation of ultra-shallow junction for CMOS devices at the sub-100 nm node is driving significant efforts in developing thermal processing to give rise to high dopant activation in combination with limited diffusion. Flash-assist Rapid Thermal Annealing™ (fRTP™) is a promising new annealing technique, which involves the heating of the bulk of the wafer to an intermediate temperature using rather conventional spike RTP, followed by a short and intense pulse of light localized on the implanted wafer surface.
In this work, we have systematically investigated the junction formation of different implants under fRTP anneals in terms of profile and devices. Co-implanted Ge and F species provide more box-like profiles with improved activation. Although leakage currents are higher for fRTP-annealed junctions than for spike-annealed junctions, appropriate fRTP process parameters and correct process conditions provide a critical tool to control and reduce the leakage current of co-implanted fRTP junctions to acceptable levels. Proper implant and anneal are requested for minimizing pattern effect and improving device performance.
Calculations of the angular distributions of scattered ions were used to simulate impact collision ion scattering spectrometry (ICISS) experiments. The calculations were performed first for 2–keV Na+ ions incident on the Pt(111) surface in the <112> azimuth. The fitting of these calculations to the experimental data provided information about the surface structure of the sample and the trajectories of the incident ions. The inclusion of a first-order decay model for Auger neutralization with the calculations for Na+ allowed the simulation of 2-keV Ne+ ions in the ICISS mode on the same Pt surface. From these simulations it was possible to extract the Auger neutralization halflife for Ne+, found to be 1.30 ± 0.10 femtoseconds.
A non-contact temperature measurement technique based on diffraction-analysis monitoring of the thermal expansion of materials is discussed. Due to the need for noncontact temperature measurements during semiconductor processing, silicon was chosen for this demonstration. The diffraction method requires a grating of suitable spatial frequency etched on the surface of the silicon wafer. The diffraction angle from the grating depends on the grating period which varies with temperature. Two symmetrically disposed incident beams are used to provide a differential measurement which is relatively independent of sample tilt. A computer system is used to monitor the diffraction order movement, from the order separation a relative temperature change can be calculated in near real-time. Temperature sensitivity for the diffraction technique is inversely dependent on the grating length (number of lines) and independent of the grating width. A sensitivity of 0.75°C is demonstrated for a 3-mm wide grating over a 20-700°C temperature range.