Despite advances in the use of topical and parenteral antimicrobial therapy, and the practice of early tangential excision, infection of the burn wound remains a leading cause of morbidity and ...mortality. The aim of this study was to survey and compare wound management and antibiotic usage in burn surgery in all UK burn centres. A postal questionnaire was used, followed up by telephone. Answers were obtained from all 39 units treating burns in the UK. A written policy on antibiotic usage was used by 13 centres. Excisions were covered routinely by prophylactic antibiotic therapy in 18 units, and three of these used antibiotic cover during all procedures in which the wound was manipulated. No routine antibiotic cover was given in 21 units. All units obtained surface swab cultures, but only two performed punch biopsy of the wounds. Quantitative bacteriology (counting colony forming units) was employed by three centres. Most units cleaned the burn with saline (17 of 39) or chlorhexidine (eight of 39) but combinations of these and other agents were also used. Nearly half (17 of 37) of those who replied had not seen any cases of proven or suspected toxic shock syndrome in the past 2 years. Four units gave prophylaxis against Staphylococcus aureus, and four gave antibiotics against Streptococcus pyogenes, despite recommendations in the literature. Twenty-nine units gave no prophylaxis. This study has revealed that there is no consensus on antibiotic usage amongst centres treating burns in the UK and that most units rely on surface swab cultures to monitor infection.
The conductivity of a finite temperature (1+1)-dimensional fermion gas described by the massive Thirring model is shown to be related to the retarded propagator of the dual boson sine-Gordon model. ...Duality provides a natural resummation which resolves infra-red problems, and the boson propagator can be related to the fermion gas at non-zero temperature and chemical potential or density. In addition, at high temperatures, we can apply a dimensional reduction technique to find resummed closed expressions for the boson self-energy and relate them to the fermion conductivity. Particular attention is paid to the discussion of analytic continuation and to the link with integrable field theories. The resummation implicit in duality provides a powerful alternative to the standard diagrammatic evaluation of transport coefficients at finite temperature.
The junctionless MOSFET (JLFET) architecture has attracted much attention as an enabling technology for ultra-scaled CMOS devices 1. The dominant scattering mechanism in JLFETs is impurity scattering ...due to its necessarily highly doped channel 1. Accordingly, III-V's may offer an even greater advantage as the channel material for JLFETs than for conventional MOSFETs as they suffer less from mobility degradation due to impurity scattering 2. Current Si CMOS devices employ non-planar architectures with high aspect ratio fins which serve to increase the on current (\mathrm{I}_{\mathrm{on}}) per chip surface area 3. This necessitates that any incarnation of a III - V MOSFET must also exploit the vertical dimension. Additionally, it must do so by employing a 'top-down' fabrication approach to remain compatible with Si CMOS processing. This requires a low \mathrm{D}_{\mathrm{it}} dielectric interface to etched III-V fin sidewalls. To date, all III-V junctionless FinFETs (JLFinFETs) demonstrated have employed fin heights which are smaller than the maximum depletion width of their respective channels, and therefore can be well modulated by the top gate only: offering little insight into the effectiveness of the gated sidewalls. We implement a low damage etch process to form high aspect ratio, \mathrm{In}_{053}\mathrm{Ga}_{047}\mathrm{As} JLFinFETs which have record performance in terms of \mathrm{I}_{\mathrm{on}} normalized to fin width.
The development of GaAs-based quantum cascade lasers incorporating indirect bandgap AlAs barriers in conjunction with ultrathin InAs layers in the active regions of the device is reported. The InAs ...layers produce a downshift of the energies of the lower lasing states, allowing laser emission to be observed at lambda = 8.34 mu m. The GaAs/InAs/AlAs devices operate in pulsed mode up to a maximum temperature of 250K, with a characteristic temperature of around 200K for T > 100K.
Polaron decay in n-type InAs quantum dots has been investigated using energy dependent, mid-infrared pump–probe spectroscopy. By studying samples with differing ground state to first excited state ...energy separations the relaxation time has been measured between ∼40 and
60
meV
. The low-temperature decay time increases with increasing detuning between the pump energy and the optical phonon energy and is maximum
(55
ps)
at
56
meV
. From the experimentally determined decay times we are able to extract a low-temperature optical phonon lifetime of
13
ps
for InAs QDs. We find that the polaron decay time decreases by a factor of ∼2 at room temperature due to the reduction of the optical phonon lifetime.
Under certain conditions the collision and intercommutation of two cosmic strings can result in the formation of a third string, with the three strings then remaining connected at Y-junctions. The ...kinematics and dynamics of collisions of this type have been the subject of analytical and numerical analyses in the special case in which the strings are Nambu-Goto. Cosmic strings, however, may well carry currents, in which case their dynamics is not given by the Nambu-Goto action. Our aim is to extend the kinematic analysis to more general kinds of string model. We focus in particular on the collision of strings described by conservative elastic string models, characteristic of current carrying strings, and which are expected to form in a cosmological context. As opposed to Nambu-Goto strings collisions, we show that in this case the collision cannot lead to the formation of a third elastic string: if dynamically such a string forms then the joining string must be described by a more general equation of state. This process will be studied numerically in a forthcoming publication.
Summary
Background
Scabies is a common parasitic skin condition that causes considerable morbidity globally. Clinical and epidemiological research for scabies has been limited by a lack of ...standardization of diagnostic methods.
Objectives
To develop consensus criteria for the diagnosis of common scabies that could be implemented in a variety of settings.
Methods
Consensus diagnostic criteria were developed through a Delphi study with international experts. Detailed recommendations were collected from the expert panel to define the criteria features and guide their implementation. These comments were then combined with a comprehensive review of the available literature and the opinion of an expanded group of international experts to develop detailed, evidence‐based definitions and diagnostic methods.
Results
The 2020 International Alliance for the Control of Scabies (IACS) Consensus Criteria for the Diagnosis of Scabies include three levels of diagnostic certainty and eight subcategories. Confirmed scabies (level A) requires direct visualization of the mite or its products. Clinical scabies (level B) and suspected scabies (level C) rely on clinical assessment of signs and symptoms. Evidence‐based, consensus methods for microscopy, visualization and clinical symptoms and signs were developed, along with a media library.
Conclusions
The 2020 IACS Criteria represent a pragmatic yet robust set of diagnostic features and methods. The criteria may be implemented in a range of research, public health and clinical settings by selecting the appropriate diagnostic levels and subcategories. These criteria may provide greater consistency and standardization for scabies diagnosis. Validation studies, development of training materials and development of survey methods are now required.
What is already known about this topic?
The diagnosis of scabies is limited by the lack of accurate, objective tests. Microscopy of skin scrapings can confirm the diagnosis, but it is insensitive, invasive and often impractical.
Diagnosis usually relies on clinical assessment, although visualization using dermoscopy is becoming increasingly common.
These diagnostic methods have not been standardized, hampering the interpretation of findings from clinical research and epidemiological surveys, and the development of scabies control strategies.
What does this study add?
International consensus diagnostic criteria for common scabies were developed through a Delphi study with global experts.
The 2020 International Alliance for the Control of Scabies (IACS) Criteria categorize diagnosis at three levels of diagnostic certainty (confirmed, clinical and suspected scabies) and eight subcategories, and can be adapted to a range of research and public health settings.
Detailed definitions and figures are included to aid training and implementation. The 2020 IACS Criteria may facilitate the standardization of scabies diagnosis.
What is already known about this topic?
The diagnosis of scabies is limited by the lack of accurate, objective tests. Microscopy of skin scrapings can confirm the diagnosis, but it is insensitive, invasive and often impractical.
Diagnosis usually relies on clinical assessment, although visualization using dermoscopy is becoming increasingly common.
These diagnostic methods have not been standardized, hampering the interpretation of findings from clinical research and epidemiological surveys, and the development of scabies control strategies.
What does this study add?
International consensus diagnostic criteria for common scabies were developed through a Delphi study with global experts.
The 2020 International Alliance for the Control of Scabies (IACS) Criteria categorize diagnosis at three levels of diagnostic certainty (confirmed, clinical and suspected scabies) and eight subcategories, and can be adapted to a range of research and public health settings.
Detailed definitions and figures are included to aid training and implementation. The 2020 IACS Criteria may facilitate the standardization of scabies diagnosis.
The diagnosis and treatment of burn wound infection is commonly determined by clinical impression and the qualitative results of surface swabs. It has been suggested that quantitative bacteriology ...from burn wound biopsies confirms burn wound infection and improves patient management. Methods for quantitating surface flora have been described, but comparisons with biopsy specimens have been contradictory. The quantitative and qualitative results of 141 pairs of biopsies and surface swabs, from 74 burn patients, were compared.
Staph. aureus was the commonest organism isolated (29 per cent of biopsies and 35 per cent of swabs). Recovery of the same set of species from biopsy and swab occurred in 54 per cent of pairs. There was a significant correlation between the bacterial count obtained by biopsy and by surface swab (
P < 0.001), but using various threshold values, the predictive value of the counts obtained by one method to predict the counts obtained by the other was poor. Parallel cultures taken on 18 occasions, showed a significant correlation between bacterial counts obtained from two biopsies or two swabs taken simultaneously (
P < 0.002), but there was wide variation in bacterial densities from the same burn wound at the same time. Recovery of the same set of species from both biopsies occurred in 56 per cent of pairs, and from both swabs in 50 per cent of pairs. The use of quantitative microbiology in burns is limited by the unreliability of a single surface swab or biopsy to represent the whole burn wound.
PDF
