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Norovirus (NoV) infections occur very frequently yet are rarely diagnosed. In Denmark, NoV infections are not under surveillance. We aimed to collect and describe existing laboratory-based NoV data. National NoV laboratory data were collected for 2011–2018, including information on patient identification number, age and sex, requesting physician, analysis date and result. We defined positive patient-episodes by using a 30-day time window and performed descriptive and time series analysis. Diagnostic methods used were assessed through a survey. We identified 15 809 patient-episodes (11%) out of 142 648 tested patients with an increasing trend, 9366 in 2011 vs. 32 260 in 2018. This corresponded with a gradual introduction of polymerase chain reaction analysis in laboratories. The highest positivity rate was in patients aged <5 years (15%) or >85 years (17%). There was a large difference in test performance over five Danish geographical regions and a marked seasonal variation with peaks from December to February. This is the first analysis of national NoV laboratory data in Denmark. A future laboratory-based surveillance system may benefit public health measures by describing trend, burden and severity of seasons and possibly pinpoint hospital outbreaks.
IR spectroscopy in the range 12–230 μm with the SPace IR telescope for Cosmology and Astrophysics (SPICA) will reveal the physical processes governing the formation and evolution of galaxies and black holes through cosmic time, bridging the gap between the James Webb Space Telescope and the upcoming Extremely Large Telescopes at shorter wavelengths and the Atacama Large Millimeter Array at longer wavelengths. The SPICA, with its 2.5-m telescope actively cooled to below 8 K, will obtain the first spectroscopic determination, in the mid-IR rest-frame, of both the star-formation rate and black hole accretion rate histories of galaxies, reaching lookback times of 12 Gyr, for large statistically significant samples. Densities, temperatures, radiation fields, and gas-phase metallicities will be measured in dust-obscured galaxies and active galactic nuclei, sampling a large range in mass and luminosity, from faint local dwarf galaxies to luminous quasars in the distant Universe. Active galactic nuclei and starburst feedback and feeding mechanisms in distant galaxies will be uncovered through detailed measurements of molecular and atomic line profiles. The SPICA’s large-area deep spectrophotometric surveys will provide mid-IR spectra and continuum fluxes for unbiased samples of tens of thousands of galaxies, out to redshifts of z ~ 6.
A new generation of solar instruments provides improved spectral, spatial, and temporal resolution, thus facilitating a better understanding of dynamic processes on the Sun. High-resolution observations often reveal multiple-component spectral line profiles, e.g., in the near-infrared He i 10830 Å triplet, which provides information about the chromospheric velocity and magnetic fine structure. We observed an emerging flux region, including two small pores and an arch filament system, on 2015 April 17 with the ‘very fast spectroscopic mode’ of the GREGOR Infrared Spectrograph (GRIS) situated at the 1.5-meter GREGOR solar telescope at Observatorio del Teide, Tenerife, Spain. We discuss this method of obtaining fast (one per minute) spectral scans of the solar surface and its potential to follow dynamic processes on the Sun. We demonstrate the performance of the ‘very fast spectroscopic mode’ by tracking chromospheric high-velocity features in the arch filament system.
Many clinics in rural western Kenya lack access to safe water and hand-washing facilities. To address this problem, in 2005 a programme was initiated to install water stations for hand washing and drinking water in 109 health facilities, train health workers on water treatment and hygiene, and motivate clients to adopt these practices. In 2008, we evaluated this intervention's impact by conducting observations at facilities, and interviewing staff and clients about water treatment and hygiene. Of 30 randomly selected facilities, 97% had water stations in use. Chlorine residuals were detectable in at least one container at 59% of facilities. Of 164 interviewed staff, 79% knew the recommended water-treatment procedure. Of 298 clients, 45% had received training on water treatment at a facility; of these, 68% knew the recommended water-treatment procedure. Use of water stations, water treatment, and client training were sustained in some facilities for up to 3 years.
Meta-analyses suggest that reboxetine may be less effective than other antidepressants. Such comparisons may be biased by lower adherence to reboxetine and subsequent handling of missing outcome data. This study illustrates how to adjust for differential non-adherence and hence derive an unbiased estimate of the efficacy of reboxetine compared with citalopram in primary care patients with depression.
A structural mean modelling (SMM) approach was used to generate adherence-adjusted estimates of the efficacy of reboxetine compared with citalopram using GENetic and clinical Predictors Of treatment response in Depression (GENPOD) trial data. Intention-to-treat (ITT) analyses were performed to compare estimates of effectiveness with results from previous meta-analyses.
At 6 weeks, 92% of those randomized to citalopram were still taking their medication, compared with 72% of those randomized to reboxetine. In ITT analysis, there was only weak evidence that those on reboxetine had a slightly worse outcome than those on citalopram [adjusted difference in mean Beck Depression Inventory (BDI) scores: 1.19, 95% confidence interval (CI) –0.52 to 2.90, p = 0.17]. There was no evidence of a difference in efficacy when differential non-adherence was accounted for using the SMM approach for mean BDI (–0.29, 95% CI –3.04 to 2.46, p = 0.84) or the other mental health outcomes.
There was no evidence of a difference in the efficacy of reboxetine and citalopram when these drugs are taken and tolerated by depressed patients. The SMM approach can be implemented in standard statistical software to adjust for differential non-adherence and generate unbiased estimates of treatment efficacy for comparisons of two (or more) active interventions.
We developed a syndromic surveillance (SyS) concept using emergency dispatch, ambulance and emergency-department data from different European countries. Based on an inventory of sub-national emergency data availability in 12 countries, we propose framework definitions for specific syndromes and a SyS system design. We tested the concept by retrospectively applying cumulative sum and spatio-temporal cluster analyses for the detection of local gastrointestinal outbreaks in four countries and comparing the results with notifiable disease reporting. Routine emergency data was available daily and electronically in 11 regions, following a common structure. We identified two gastrointestinal outbreaks in two countries; one was confirmed as a norovirus outbreak. We detected 1/147 notified outbreaks. Emergency-care data-based SyS can supplement local surveillance with near real-time information on gastrointestinal patients, especially in special circumstances, e.g. foreign tourists. It most likely cannot detect the majority of local gastrointestinal outbreaks with few, mild or dispersed cases.
Wildlife reservoir hosts of bovine tuberculosis (bTB) include Eurasian badgers (Meles meles) and brushtail possum (Trichosurus vulpecula) in the UK and New Zealand, respectively. Similar species warrant further investigation in the northern lower peninsula of Michigan, USA due to the continued presence of bTB on cattle farms. Most research in Michigan, USA has focused on interactions between white-tailed deer (Odocoileus virginianus) and cattle (Bos taurus) for the transmission of the infectious agent of bTB, Mycobacterium bovis, due to high deer densities and feeding practices. However, limited data are available on medium-sized mammals such as Virginia opossum (Didelphis virginiana; hereafter referred to as opossum) and their movements and home range in Michigan near cattle farms. We conducted surveillance of medium-sized mammals on previously depopulated cattle farms for presence of M. bovis infections and equipped opossum with Global Positioning System (GPS) technology to assess potential differences in home range between farms inside and outside the bTB core area that has had cattle test positive for M. bovis. On farms inside the bTB core area, prevalence in opossum was comparable [6%, 95% confidence interval (CI) 2·0–11·0] to prevalence in raccoon (Procyon lotor; 4%, 95% CI 1·0–9·0, P = 0·439) whereas only a single opossum tested positive for M. bovis on farms outside the bTB core area. The prevalence in opossum occupying farms that had cattle test positive for M. bovis was higher (6·4%) than for opossum occupying farms that never had cattle test positive for M. bovis (0·9%, P = 0·01). Mean size of home range for 50% and 95% estimates were similar by sex (P = 0·791) both inside or outside the bTB core area (P = 0·218). Although surveillance efforts and home range were not assessed on the same farms, opossum use of farms near structures was apparent as was selection for farms over surrounding forested habitats. The use of farms, stored feed, and structures by opossum, their ability to serve as vectors of M. bovis, and their propensity to ingest contaminated sources of M. bovis requires additional research in Michigan, USA.
We recently developed a scattering model based on the scalar scattering theory. In this contribution we present how we used the scattering model to investigate interface textures with optimized scattering properties. We used the simulated annealing algorithm to find optimized surface textures and applied the ASA device simulator to evaluate the influence of these optimized textures on the performance of thin film silicon solar cells. We found that the lateral feature size of the textures is crucial for efficient scattering of the incident light.
Accurate data on West Nile virus (WNV) cases help guide public health education and control activities, and impact regional WNV blood product screening procedures. During an outbreak of WNV disease in Arizona, records from patients with meningitis or encephalitis were reviewed to determine the proportion tested for WNV. Of 60 patients identified with meningitis or encephalitis, 24 (40%) were tested for WNV. Only 12 (28%) of 43 patients aged <50 years were tested for WNV compared to 12 (71%) of 17 patients aged ⩾50 years (P<0·01). Patients with clinical signs of weakness or paralysis, elevated CSF protein, admitted to an inpatient facility, or discharged to a rehabilitation facility were also more likely to have WNV testing performed. The lack of testing in younger age groups and in those with less severe disease probably resulted in substantial underestimates of WNV neuroinvasive disease burden.
Because of worldwide increase of catastrophes and recent terrorist attacks, hospitals and physicians are devoting increased attention to disaster and mass casualty incident (MCI) preparedness not only outside but also inside hospitals. In case of a terrorist attack physicians have to cope with injuries caused by conventional, biological, chemical, or radioactive weapons.
The aim of this study was to evaluate the current state of preparedness of German hospitals and physicians in case of an MCI or terrorist attack and to compare those results to the preparedness of hospitals and physicians from Austria, Switzerland, the United States of America and a worldwide collective.
Materials and Methods
Using an online questionnaire, we interviewed 1343 physicians in Germany, Austria, Switzerland, the US and a worldwide collective. The replies were analyzed statistically with the Shapiro-Walk test and the Mann-Whitney-U test.
in Germany physicians are less prepared than their colleagues worldwide for disasters inside and outside hospitals. 48,4% of German physicians (37% worldwide) did not know their area of responsibility as a physician in case of an “internal” emergency (fire, water pipe burst, power cut), even though 30,2% of German physicians (29,1% worldwide) have already had a real emergency in their hospital. Only 65,3% of physicians in Germany (75,5% worldwide) knew their area of responsibility in case of an MCI; MCI training was given less often in Germany (42,7%) than worldwide (64,3%). Most physicians in every country were unaware of injury patterns and treatment strategies in patients following bombings or nuclear, chemical and biological contamination.
Hospital Physicians are insufficiently prepared for internal emergencies and MCIs. There is a need for more drills in hospitals. In spite of the recent threat of terrorist attacks, the physicians' emergency training should be modified to accommodate the increased risk of catastrophes and terrorist attacks.
Developing an e-learning platform addressing security and rescue forces to eradicate the lack of disaster preparedness underscored by diverse studies. In order to reach this aim the performance of a needs analysis is essential.
The audience of security and rescue forces was clustered in (emergency) physicians, fire-fighters, policemen, Paramedics and members of the Federal Agency for Technical Relief (THW). For each cluster a questionnaire was developed and corrected by specialists in disaster care. The questions were about previous knowledge, habits of studying; further training habits and internet requirements.
The questioner was posted online during 4 months and was filled in by 1142 persons (141 physicians, 194 fire-fighters, 108 policeman, 444 rescue workers and 255 members of the THW). The biggest lacks in previous knowledge were shown in reacting on CBRN-incidents. 64, 1% thought they were not able to act correctly in case of chemical contamination. The most important learning tools were books, lectures, seminars and the principle of learning by doing. The reasons for using an e-learning platform were saving time, high quality of the tutorials (77% thought it important), quicker reach of information, multimedia formats of the taught facts and links to further information. 55, 2% were slightly unsatisfied with the actual pool of further trainings. The most frequently used sources of information were the internet (78, 8% use it frequently) and colleagues.
The survey shows that lacks in disaster preparedness in Germany definitively exist but it also reflects that most of the security and rescue forces are motivated to do further trainings and use therefore new technologies. But they require a high quality of teaching and a reasonable use of them. There is a need for using innovative Methods, and user-friendly web-based instruction and information modules to address all security and rescue forces in Germany.
Nanofluids, consisting of nanometric particles suspended in a base fluid, have become a new alternative for improving heat management technology. Silver, which is known to exhibit pretty high electrical and thermal conductivity among metals, has been selected for this research. At present, we are focused on the study of the size- and shape-controlled synthesis conditions of silver nanocrystals in polyol media. Control of crystal size and shape at the nanoscale were achieved by suitable selection of the synthesis conditions and the presence of habit-controlling agents like chloride ions. Silver nanostructures (faceted crystals, wires, rods) were remarkable monodisperse in size and their dimension could be controlled in the 30-50nm range (particles) and 24-127nm in thickness for rods or wires.
The focus of this paper is the characterization of novel thermophotovoltaic (TPV) cell designs which employ a monovalent barrier layer in the p-n junction. The use of a barrier layer enables these cells to operate at longer wavelengths, higher efficiencies, and higher operating temperatures. Initial designs have been made using gallium antimonide (GaSb), which is one of the more common TPV materials. Simulations were performed using Sentaurus by Synopsys to determine barrier materials as well as to optimize the cell. The p-B-n cell was then compared to a simple p-n junction. The simulations show that a p-B-n cell outperforms a typical p-n junction. Additionally, we expect to see increased performance differentials from this device structure when moving to longer wavelength devices.
Over the past few years, thermoelectric (TE) materials have been receiving an increasing amount of attention owing to their promising potential for energy conversion and thermal management applications. Thermal characterisation techniques offer a powerful tool in investigating and optimizing the TE device performance. In addition, they can provide a better understanding of the underlying fundamental principles such as Peltier effects at the interfaces of the active medium. In this paper, we present the design and thermal characterisation of integrated highspeed microcoolers based on SiGe superlattices. The electrode metalisation is laid out as a coplanar waveguide, enabling to supply electrical pulses with short rise times to the coolers. We employ a variety of CCD-based transient thermoreflectance imaging methods to perform an extensive dynamic thermal analysis. These techniques provide 2-D temperature maps of the chip surface with ∼100ns temporal and submicron spatial resolution without the need to scan the sample. Net cooling in the 2 degree range is observed, with response times well below 1μs. This is almost two orders of magnitude faster compared to the best in the literature. The obtained images also confirm the previous observations that the Peltier cooling term responds faster than the Joule heating term, in agreement with their expected locality and associated thermal mass. This provides potential to study ultrafast electron-phonon interactions during Peltier effects.
In this work, thin films of Bi2Te3 and Sb2Te3 were synthesized by the nanoalloying approach: Nanoscale layers of the elements Element nanoscale layers of Bi, Sb and Te are stoichiometrically deposited on a cold substrate using a MBE setup and subjected to an annealing process in which a solid state reaction yielding Bi2Te3 and Sb2Te3 takes place. Besides the two binary compounds, nanoscale multilayer (ML) stacks of 9 nm Bi2Te3/9 nm Sb2Te3 were created. The electrical transport properties of the binary compounds were determined in dependence of composition. Compound formation was directly observed in temperature-dependent in-situ XRD scans and was found to start at ∼100 °C. The stability of the Bi2Te3/Sb2Te3 ML nanostructure against temperature-driven interdiffusion during annealing was examined by SIMS and TEM for an annealing temperature of 150 and 250 °C, respectively. A comparative TEM study of the as grown and annealed state is presented.
Nano-alloyed p-type Sb2Te3 and n-type Bi2Te3 thin films were grown on SiO2/Si and BaF2 substrates by molecular beam epitaxy (MBE) in two steps: (i) Repeated deposition of five-layer stacks with sequence Te-X-Te-X-Te (X = Sb or Bi) with elemental layer thicknesses of 0.2 nm on substrates at room temperature, (ii) annealing at 250 °C for two hours at which phase formation of Sb2Te3 or Bi2Te3 occurred. The room temperature MBE deposition method reduces surface roughness, allows the use of non lattice-matched substrates, and yields a more accurate and easier control of the Te content compared to Bi2Te3 thin films, which were epitaxially grown on BaF2 substrates at 290 °C. X-ray diffraction revealed that the thin films were single phase, poly-crystalline, and textured. The films showed grain sizes of 500 nm for Sb2Te3 and 250 nm for Bi2Te3, analyzed by transmission electron microscopy (TEM). The in-plane transport properties (thermopower S, electrical conductivity σ, charge carrier density n, charge carrier mobility μ, power factor S2σ) were measured at room temperature. The nano-alloyed Sb2Te3 thin film revealed a remarkably high power factor of 29 μW cm-1 K-2 similar to epitaxially grown Bi2Te3 thin films and Sb2Te3 single crystalline bulk materials. This large power factor can be attributed to a high charge carrier mobility of 402 cm2 V−1 s-1 similar to high-ZT Bi2Te3/Sb2Te3 superlattices. However, for the nano-alloyed Bi2Te3 thin film a low power factor of 8 μW cm−1 K-2 and a low charge carrier mobility of 80 cm2 V−1 s−1 were found. Detailed microstructure and phase analyses were carried out by energy-filtered TEM in cross-sections. Quantitative chemical analysis by energy-dispersive x−ray spectroscopy (EDS) was also applied. In Bi2Te3 thin films, few nanometer thick Bi-rich blocking layers at grain boundaries and Te fluctuations by 1.3 at.% within the grains were observed. The small charge carrier densities are explained by a reduced antisite defect density due to the low temperatures to which the thin films were exposed during annealing.