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Acute tonsillitis represents a significant proportion of admissions to ENT departments nationally. Given current hospital pressures, it is vital to look for safe alternatives to admission. This study explores the safe management of patients in an ambulatory medical unit, without the need for admission.
A retrospective review of 48 patients’ notes was carried out. Following the development and implementation of a guideline for acute tonsillitis, a prospective re-audit of 41 patients was carried out, measuring length of stay, overnight admissions and re-admissions.
The rate of overnight admission following implementation of the guideline fell from 0.75 to 0.29, and average length of stay dropped from 19.2 to 9.5 hours. There were two re-admissions in each cycle of the audit, which represents a non-significant increase.
The tonsillitis guideline has significantly reduced admissions and length of stay. Re-admissions remain low, demonstrating that this is a safe and cost-effective intervention.
Supernova remnants (SNRs) are diffuse extended sources characterized by a complex morphology and a non-uniform distribution of ejecta. Such a morphology reflects pristine structures and features of the progenitor supernova (SN) and the early interaction of the SN blast wave with the inhomogeneous circumstellar medium (CSM). Deciphering the observations of SNRs might open the possibility to investigate the physical properties of both the interacting ejecta and the shocked CSM. This requires accurate numerical models which describe the evolution from the SN explosion to the remnant development and which connect the emission properties of the remnants to the progenitor SNe. Here we show how multi-dimensional SN-SNR hydrodynamic models have been very effective in deciphering observations of SNR Cassiopeia A and SN 1987A, thus unveiling the structure of ejecta in the immediate aftermath of the SN explosion and constraining the 3D pre-supernova structure and geometry of the environment surrounding the progenitor SN.
Acceleration times of particles responsible for the gamma-rays in supernova remnants (SNRs) are comparable with SNR age. If the number of particles starting acceleration was varying during early times after the supernova explosion then this variation should be reflected in the shape of the gamma-ray spectrum. In order to analyse this effect, we consider the time variation of the radio spectral index in SN1987A and solution of the non-stationary equation for particle acceleration. We reconstruct evolution of the particle injection in SN1987A, apply it to derive the particle momentum distribution in IC443 and model its gamma-ray spectrum. We show that: i) observed break in the proton spectrum around 50 GeV in IC443 is a consequence of the variation of the cosmic ray injection; ii) shape of the hadronic gamma-ray spectrum in SNRs critically depends on the temporal variation of the cosmic ray injection in the immediate post explosion phases.
There are few quantitative studies on deep-sea biodiversity from the Indian Ocean, particularly on the mid-ocean ridges (MOR). We investigated the benthic megafaunal community structure of the Indian Ocean MOR at the Carlsberg Ridge (CR) using underwater video observation by the Television Gripper (TVG) and Ocean Floor Observation System (OFOS) during a multidisciplinary scientific cruise in 2007. Our aim was to observe megafaunal assemblages and their variation with bottom substrate at different geological settings in the CR region. The fauna was identified at best possible taxonomic resolution from video images and data were quantified by photogrammetry. Variation of substratum type was greatest in the deeper areas of the CR region, with substrata varying from fine sediments to basalts. A total of eight substratum types and 90 megafaunal taxa, representing seven phyla, have been classified throughout the 10 transects. Faunal abundances ranged between 171.3 to 5.7 animals 1000 m−2, with higher abundances at the shallower transects, in off-axial highs, and lower at deeper zones, on the rift valley wall and floor. Cnidarians were dominant at off-axial highs while echinoderms prevailed at rift valley floor transects. Other frequently encountered faunal components were poriferans and chordates, observed at shallower as well as deeper transects. This is the first detailed investigation of megafaunal assemblages from the Indian Ocean MOR.
EMU is a wide-field radio continuum survey planned for the new Australian Square Kilometre Array Pathfinder (ASKAP) telescope. The primary goal of EMU is to make a deep (rms ∼ 10 μJy/beam) radio continuum survey of the entire Southern sky at 1.3 GHz, extending as far North as +30° declination, with a resolution of 10 arcsec. EMU is expected to detect and catalogue about 70 million galaxies, including typical star-forming galaxies up to z ∼ 1, powerful starbursts to even greater redshifts, and active galactic nuclei to the edge of the visible Universe. It will undoubtedly discover new classes of object. This paper defines the science goals and parameters of the survey, and describes the development of techniques necessary to maximise the science return from EMU.
Long-term physical conditions (LTCs) consume the largest share of healthcare budgets. Although common mental disorders (CMDs) and LTCs often co-occur, the potential impact of improved mental health treatment on severe disability and hospital admissions for physical health problems remains unknown.
A cross-sectional study of 7403 adults aged 16–95 years living in private households in England was performed. LTCs were ascertained by prompted self-report. CMDs were ascertained by structured clinical interview. Disability was assessed using questions about problems with activities of daily living. Population impact and potential preventive gain were estimated using population-attributable fraction (PAF), and conservative estimates were obtained using ‘treated non-cases’ as the reference group.
Of the respondents, 20.7% reported at least one LTC. The prevalence of CMDs increased with the number of LTCs, but over two-thirds (71.2%) of CMD cases in people with LTCs were untreated. Statistically significant PAFs were found for CMDs and recent hospital admission [13.5%, 95% confidence intervals (CI) 6.6–20.0] and severe disability (31.3%, 95% CI 27.1–35.2) after adjusting for LTCs and other confounders. Only the latter remained significant when using the most conservative estimate of PAF (21.8%, 95% CI 14.0–28.9), and this was reduced only slightly when considering only participants with LTCs (18.5%, 95% CI 7.9–27.9).
Better treatments for CMDs in people with LTCs could achieve almost the same population health gain in terms of reducing severe disability as those targeted at the entire population. Interventions to reduce the prevalence of CMDs among people with LTCs should be part of routine medical care.
This paper reports on the fabrication and characterization of thin-film nanocomposites comprised of tangled carbon nanotubes in a polymer matrix. The concentration of nanotubes in the polymer was significantly increased using detonation nanodiamonds. Nanodiamonds reduce the surface forces between the polymer and the nanotubes and mitigate the agglomeration problem of nanotubes in polymer. This resulted in thinner and more uniform networks that are efficient absorbers of infrared energy over a broad spectrum, ranging from the visible to the mid-wavelength infrared. An infrared absorbance of 97% was achieved for a 1.6 μm thick nanocomposite film across the spectral range of 714 nm to 5 μm. The films are mechanically and thermally stable up to 300 °C, and can be integrated with microbolometers to enhance their responsivity.
Sites described as tropical montane cloud forests differ greatly, in part because observers tend to differ in their opinion as to what constitutes “frequent and prolonged” immersion in cloud. This definitional difficulty interferes with hydrological analyses, assessments of environmental impacts on ecosystems, and biogeographical analyses of cloud forest communities and species. Quantitative measurements of cloud immersion can be obtained on site, but the observations are necessarily spatially limited, although well-placed observers can examine 10–50 km of a mountain range under rainless conditions. Regional analyses, however, require observations at a broader scale. This chapter discusses remote sensing and modeling approaches that can provide quantitative measures of the spatio-temporal patterns of cloud cover and cloud immersion in tropical mountain ranges. These approaches integrate remote sensing tools of various spatial resolutions and frequencies of observation, digital elevation models, regional atmospheric models, and ground-based observations to provide measures of cloud cover, cloud base height, and the intersection of cloud and terrain. This combined approach was applied to the Monteverde region of northern Costa Rica to illustrate how the proportion of time the forest is immersed in cloud may vary spatially and temporally. The observed spatial variation was largely due to patterns of airflow over the mountains. The temporal variation reflected the diurnal rise and fall of the orographic cloud base, which was influenced in turn by synoptic weather conditions, the seasonal movement of the Intertropical Convergence Zone and the north-easterly trade winds. […]
Ecological changes observed in cloud forests in the Monteverde area, northern Costa Rica, including disappearance of anuran populations and expansion of bird and bat ranges to higher elevations, have been linked to an increasing trend in dry-season mist-free days. Prior studies suggest that this trend may be influenced by both large-scale processes of climate change and regional-scale changes in land cover. Preliminary investigations exploring the impact of land use on cloud formation indicated that drying and warming of boundary layer air in response to lowland deforestation leads to increased cloud base heights. In the present study, numerical model experiments utilizing realistic land-use scenarios and atmospheric conditions are used to further explore the impact of land-use change on orographic cloud formation. The Regional Atmospheric Modeling System (RAMS) was used to simulate orographic cloud formation during the time period of 1–14 March 2003 in the Monteverde region for pristine, current, and future land-use scenarios. The simulations were initiated from the same atmospheric conditions and subject to similar lateral boundary conditions. Comparisons against observations showed that RAMS was capable of realistically simulating the nature of orographic cloud formation and boundary-layer thermodynamics. Numerical simulations indicated that deforestation in the lowlands and adjacent pre-montane areas results in an increase in average cloud base height and a consequent decrease in the areal extent of montane forests immersed in clouds. In the current and future land-use scenarios, warmer and drier air is found over the lowlands and pre-montane areas. […]
The development of high power, high efficiency silicon carbide RF MESFETs is reported. High power densities of over 3W/mm have been measured for devices with total power output in excess of 25W. The devices have been fabricated using a novel lateral epitaxy technique. The MESFET employs a buried p-type depletion stopper in order to suppress short channel effects and increase the operation voltage. The use of the depletion stopper also allows high RF signal gain, while maintaining high voltage operation capability. Single-cell components measured on-wafer demonstrate an Ft of 10 GHz and a high unilateral gain.
Packaged 6-mm RF transistors have been evaluated using amplifier circuits designed for operation in classes A, AB or C. Operation in class AB demonstrated a saturated power of 20 W and a P1dB of 15W with a linear gain of over 16 dB at Vdd of 60 V for 2.25 GHz operation. Maximum drain efficiency is 56% for class AB operation, 48% at 1 dB compression point and 72% for class C at 2.25 GHz.
To study the clinical and molecular epidemiology of vancomycin-resistant Enterococcus faecium organisms causing catheter-related bacteremia in patients with cancer.
Retrospective case-control study.
University of Texas M. D. Anderson Cancer Center, a tertiary-care hospital in Houston, Texas.
Case-patients were patients with cancer who had catheter-related vancomycin-resistant E. faecium bacteremia and control-patients were patients with cancer and vancomycin-resistant E. faecium gastrointestinal colonization without infection.
Ten case-patients with catheter-related vancomycin-resistant E. faecium bacteremia were compared with 30 control-patients with gastrointestinal colonization by vancomycin-resistant E. faecium. Patients with catheter-related vancomycin-resistant E. faecium bacteremia were more likely to have required mechanical ventilation (P < .01), received total parenteral nutrition (P < .01), and had polyurethane catheters (P < .01) inserted in the femoral vein (P = .01). With the use of pulsed-fleld gel electrophoresis, 4 of the 10 catheter-related vancomycin-resistant E. faecium bacteremia isolates were genetically indistinguishable, whereas only 2 of the 30 control vancomycin-resistant E. faecium isolates displayed this same DNA pattern (P = .03).
This study suggests that catheter-related vancomycin-resistant E. faecium bacteremia occurs more frequently in patients who receive total parenteral nutrition, mechanical ventilation, and femoral catheters. (Infect Control Hosp Epidemiol 2005;26:658-661)
The deformation kinematics for radiation damage response of bulk materials is presently semi-empirical and phenomenological based on a continuum mechanics supposition: there exists a function space of continuous functions to describe material displacement, strain, strain-rate metrics by using the mathematics of differential calculus. Existing data being assembled from tests on nano-length-scale(NLS) samples provide objective evidence that the continuum mechanics supposition is not an adequate generic mathematical description for radiation damage response in surface-dominated material structures at NLS. An alternative approach will be described that uses concepts and methods from classical statistical mechanics and describe deformation kinematics as a stochastic accumulation of discrete damage events at atomic lattice nano-length-scales. Although radiation damage deformation at a lattice length-scale in solids is mechanistically different from velocity scattering developed by Boltzmann for a kinetic theory of gases, the two problem areas are technically similar and in some simply cases there are useful mathematical analogs. The technical similarities and mathematical analogs will be used to define probability density functions (number per unit volume functions) for undamaged and damaged “size and size change” lattice species (similarity to a probability density function for atomic velocities in gas theory). In general, equations for undamaged and damaged lattice density function evolution are Boltzmann-type equations, which can be approximated and solved for simple cases of radiation induced material damage. Using a path integral approach and the two probability density functions, a stochastic functional will be derived for the relative deformation between any two arbitrary spatial points in a radiation damaged material. Given the relative deformation as an explicit functional of the undamaged and damaged lattice density functions, the kinematics metrics of relative velocity, strain, strain rate, etc., will also be functionals. In the case of radiation damage and annealing, the two lattice density functions are analog expressions to those commonly used to model “birth and death” population evolution.
Introduction. Repetitive transcranial magnetic stimulation (rTMS) has been proposed as a possible alternative to electroconvulsive therapy for the treatment of selected patients with depression, bipolar affective disorder and schizophrenia. The aim of this study was to evaluate the evidence for the effectiveness of rTMS in mood disorders and schizophrenia.
Methods. Studies were identified using MEDLINE (1966 to January 2000), EMBASE/Excerpta Medica (1980 to January 2000), Biological Abstracts and Index to Scientific and Technical Proceedings. A number of biomedical and TMS related websites were also searched. We estimated the number needed to treat to show beneficial effect of rTMS when compared with the placebo controlled group.
Results. Seven controlled trials of rTMS depression were identified. Five of these were suitable for meta-analysis and show a beneficial effect of rTMS compared to placebo, with a number needed to treat of 2·3 with a 95% confidence interval 1·6 to 4·0, total; 81 patients. A single trial of rTMS has also been performed in mania, which shows a beneficial effect of right hemisphere stimulation when compared with left hemisphere stimulation. A controlled trial in schizophrenia failed to show any benefit of rTMS.
Discussion. rTMS has demonstrable beneficial effects in depression. The extent and the duration of the anti-depressant effect of rTMS has yet to be defined. There now needs to be randomized controlled trials to compare rTMS directly with standardized electroconvulsive therapy in order to take this subject forward. With regard to the treatment of other mood disorders and schizophrenia, we are at an early stage in the assessment of further studies that are needed to examine any potential role for rTMS.
This study deals with the ecology of Lyme borreliosis in Europe.
The relationships between Borrelia burgdorferi sensu lato
spirochetes, Clethrionomys and Apodemus rodent reservoirs
and the Ixodes ricinus tick vector were investigated during 16
consecutive months in an enzootic area in Switzerland. Cultivation of ear
skin biopsies was used to isolate spirochetes from
C. glareolus, A. sylvaticus, A. flavicollis
and Glis glis. Borrelia infection was more frequently
observed in Clethrionomys
than in Apodemus. Tick xenodiagnosis was used to determine the
infectivity of rodents. The infection rate in ticks fed on
Clethrionomys was higher than that in ticks fed on Apodemus,
but Apodemus yielded more infected ticks than Clethrionomys
because of a better tick moulting success. Xenodiagnostic ticks were placed
into BSK medium to obtain isolates. Isolates
from rodents and rodent-feeding ticks were all identified as B. afzelii.
The follow-up of the infectivity status of repeatedly
recaptured rodents clearly demonstrated that these hosts remained infective
for ticks during winter till the following spring.
Comparing C. glareolus and A. sylvaticus, each rodent
species showed different host infection, different host infectivity
and contributed differently to the moulting success of feeding ticks. These
factors influence differentially the pattern of
transmission of B. afzelii from Clethrionomys voles and
Apodemus mice to I. ricinus ticks.
This paper presents results of an analytical study of microwave heating of a fluid flowing through a tube situated along the axis of a cylindrical microwave applicator. The interaction of the microwave field pattern and the fluid velocity profiles is illustrated for both laminar and turbulent flow. Resulting temperature profiles are compared with those generated by conventional heating through a surface heat flux. It is found that microwave heating offers several advantages over conventional heating.
Recently it was proposed [S.C. Jha, et al., Mater. Sci. & Eng. A119 (1989) 103 & J.D. Whittenberger, et al., J. Mat. Sci. 25, (1990) 2771] on the basis of constant velocity testing at 1300 K that dispersion strengthened NiAl composites containing about 4 wt pct HfC possess threshold stresses for creep. Further 1300 K compression testing has been conducted on NiAl+4HfC,and diametrically opposite behavior has been found: for constant load creep tests normal power law behavior was observed (strain rate proportional to the stress raised to the power n); however additional constant velocity testing still indicates that the flow stress is essentially independent of strain rate below 10−6 s−1. Examination of NiAl+4.3HfC specimens after being deformed under constant velocity conditions revealed that the original hot extruded small grain structure could be converted to large, elongated grains during testing. Such a transformation appears to be responsible for the apparent threshold stress behavior in HfC dispersed NiAl.
Results from computer simulation and experiments on ion scattering and sputtering processes in ion beam sputter deposition of high Tc superconducting and ferroelectric thin films are presented. It is demonstrated that scattering of neutralized ions from the targets can result in undesirable erosion of, and inert gas incorporation in, the growing films, depending on the ion/target atom mass ratio and ion beam angle of incidence/target/substrate geometry. The studies indicate that sputtering by Kr+ or Xe+ ions is preferable to the most commonly used Ar+ ions, since the undesirable phenomena mentioned above are minimized for the first two ions. These results are used to determine optimum sputter deposition geometry and ion beam parameters for growing multicomponent oxide thin films by ion beam sputter-deposition.