We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure coreplatform@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Bell's palsy is a lower motor neurone facial weakness of unknown aetiology, although reactivation of a virus within the facial nerve has been proposed.
Methods
A prospective study was conducted of Bell's palsy cases presenting to our paediatric ENT unit over a 19-week period, from February to June 2020. Patients were invited for severe acute respiratory syndrome coronavirus-2 antibody testing. A text-message questionnaire was sent to other ENT centres to determine their observational experience.
Results
During the study period, 17 children presented with Bell's palsy, compared with only 3 children in the same time period in the previous year (p < 0.0001). Five patients underwent severe acute respiratory syndrome coronavirus-2 antibody testing, the results of which were all negative. Four out of 15 centres questioned perceived an increased incidence in paediatric Bell's palsy.
Conclusion
Clinicians are encouraged to be vigilant to the increase in paediatric Bell's palsy seen during the coronavirus disease 2019 pandemic, which may represent a post-viral sequela of coronavirus disease 2019.
Here we review the potential of ILB 938 (IG 12132 – doi: 10.18730/60FD2), a unique faba bean accession originating from the Andean region of Colombia and Ecuador, maintained at ICARDA – International Center for Agricultural Research in the Dry Areas, with resistance to multiple biotic and abiotic stresses and carrying some useful morphological markers. It has been used as a donor of leaf-related drought adaptation traits and chocolate spot (Botrytis fabae) resistance genes in faba bean breeding programmes worldwide. From generated populations of recombinant inbred lines, quantitative traits loci associated with these useful traits have been mapped. Other markers, such as a lack of stipule-spot pigmentation and clinging pod wall, show the presence of unusual changes in biochemical pathways that may have economic value in the future.
The U.S. Army uses universal preventives interventions for several negative outcomes (e.g. suicide, violence, sexual assault) with especially high risks in the early years of service. More intensive interventions exist, but would be cost-effective only if targeted at high-risk soldiers. We report results of efforts to develop models for such targeting from self-report surveys administered at the beginning of Army service.
Methods
21 832 new soldiers completed a self-administered questionnaire (SAQ) in 2011–2012 and consented to link administrative data to SAQ responses. Penalized regression models were developed for 12 administratively-recorded outcomes occurring by December 2013: suicide attempt, mental hospitalization, positive drug test, traumatic brain injury (TBI), other severe injury, several types of violence perpetration and victimization, demotion, and attrition.
Results
The best-performing models were for TBI (AUC = 0.80), major physical violence perpetration (AUC = 0.78), sexual assault perpetration (AUC = 0.78), and suicide attempt (AUC = 0.74). Although predicted risk scores were significantly correlated across outcomes, prediction was not improved by including risk scores for other outcomes in models. Of particular note: 40.5% of suicide attempts occurred among the 10% of new soldiers with highest predicted risk, 57.2% of male sexual assault perpetrations among the 15% with highest predicted risk, and 35.5% of female sexual assault victimizations among the 10% with highest predicted risk.
Conclusions
Data collected at the beginning of service in self-report surveys could be used to develop risk models that define small proportions of new soldiers accounting for high proportions of negative outcomes over the first few years of service.
The Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) has found that the proportional elevation in the US Army enlisted soldier suicide rate during deployment (compared with the never-deployed or previously deployed) is significantly higher among women than men, raising the possibility of gender differences in the adverse psychological effects of deployment.
Method
Person-month survival models based on a consolidated administrative database for active duty enlisted Regular Army soldiers in 2004–2009 (n = 975 057) were used to characterize the gender × deployment interaction predicting suicide. Four explanatory hypotheses were explored involving the proportion of females in each soldier's occupation, the proportion of same-gender soldiers in each soldier's unit, whether the soldier reported sexual assault victimization in the previous 12 months, and the soldier's pre-deployment history of treated mental/behavioral disorders.
Results
The suicide rate of currently deployed women (14.0/100 000 person-years) was 3.1–3.5 times the rates of other (i.e. never-deployed/previously deployed) women. The suicide rate of currently deployed men (22.6/100 000 person-years) was 0.9–1.2 times the rates of other men. The adjusted (for time trends, sociodemographics, and Army career variables) female:male odds ratio comparing the suicide rates of currently deployed v. other women v. men was 2.8 (95% confidence interval 1.1–6.8), became 2.4 after excluding soldiers with Direct Combat Arms occupations, and remained elevated (in the range 1.9–2.8) after adjusting for the hypothesized explanatory variables.
Conclusions
These results are valuable in excluding otherwise plausible hypotheses for the elevated suicide rate of deployed women and point to the importance of expanding future research on the psychological challenges of deployment for women.
Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a major wheat disease that can inflict yield losses of up to 70% on susceptible varieties under favourable environmental conditions. The timely identification of plant genetic resources likely to possess novel resistance to this disease would facilitate the rapid development of resistant wheat varieties. The focused identification of germplasm strategy (FIGS) approach was used to predict stripe rust resistance in a collection of wheat landraces conserved at ICARDA genebank. Long-term climate data for the collection sites, from which these accessions originated and stripe rust evaluation scores for one group of accessions were presented to three different non-linear models to explore the trait×collection site environment interactions. Patterns in the data detected by the models were used to predict stripe rust resistance in a second and different set of accessions. The results of the prediction were then tested against actual evaluation scores of the disease in the field. The study mimics the real scenario where requests are made to plant genetic resources curators to provide accessions that are likely to possess variation for specific traits such as disease resistance.
The models used were able to identify stripe rust-resistant accessions with a high degree of accuracy. Values as high as 0·75 for area under the curve and 0·45 for Kappa statistics, which quantify the agreement between the models’ predictions and the curator's disease scores, were achieved. This demonstrates a strong environmental component in the geographic distribution of resistance genes and therefore supports the theoretical basis for FIGS. It is argued that FIGS will improve the rate of gene discovery and efficiency of mining genetic resource collections for adaptive traits by reducing the number of accessions that are normally required for evaluation to identify such variation.
Gravitational microlensing is a well established and unique field of time-domain astrophysics. For two decades microlensing surveys have been regularly observing millions of stars to detect elusive events that follow a characteristic Paczyński lightcurve. This workshop reviewed the current state of the field, and covered the major topics related to microlensing: searches for extrasolar planets, and studies of dark matter. There were also discussions of issues relating to the organisation of follow-up observations for microlensing, as well as serendipitous scientific outcomes resulting from extensive microlensing data.
Las Cumbres Observatory Global Telescope Network (LCOGT) is currently building a new kind of general-purpose astronomical facility: a fully robotic network of telescopes of 2m, 1m and 0.4m apertures and homogeneous instrumentation. A pan-network approach to scheduling (rather than per individual telescope) offers redundancy in the event of poor weather or technical failure, as well as the ability to observe a target around the clock. Here we describe the network design and instrumentation under development, together with the main science programmes already being lead by LCOGT staff.
The technology of large area electronics has made significant progress in recent years because of the fast maturing excimer laser annealing process. The new thin film transistors based on laser processed poly silicon provide unprecedented performance over the traditional thin film transistors using amorphous silicon. They open up the possibility of building flat panel displays and imagers with higher integration and performance. In this paper, we will review the progress of poly-Si thin film transistor technology with emphasis on imager applications. We also discuss the challenges of future improvement of flat panel imagers based on this technology.
Pulsed Excimer-Laser Annealing (ELA) has become an important technology to produce high performance, poly-Si Thin Film Transistors (TFTs) for large area electronics. The much-improved performance of these poly-Si TFTs over the conventional hydrogenated amorphous Si TFTs enables the possibility of building next generation flat panel imagers with higher-level integration and better noise performance. Both the on-glass integration of peripheral driver electronics to reduce the cost of interconnection and the integration of a pixel level amplifier to improve the noise performance of large area imagers have been demonstrated and are discussed in this paper.
We report studies of the image-blur effects caused by lateral cross-talk between neighboring pixels of large-area amorphous silicon (a-Si:H) image sensors. The lateral conduction is attributed to three effects: conduction along the interface between the a-Si:H film and the underlying passivation; field-dependent electron injection at the edge of the sensor; and a field enhancement of the interface conduction due to the bias applied to the address lines. We show that the cross-talk can be controlled by choice of the operating conditions and optimization of the materials.
The pixel cross-talk is investigated in two-dimensional amorphous silicon (a-Si:H) imager arrays based on the new high fill factor design. In this configuration a continuous a-Si:H sensor extends over the whole surface of the imager, and a buried insulator material with low dielectric constant is used to separate the sensor from the underlying active matrix readout circuit. We find that the lateral conduction between neighboring pixels is mainly determined by the quality of the buried insulator-sensor interface, rather than the specific buried material itself. Minimum cross-talk values below 1% are obtained for different insulator materials including silicon oxynitride and thicker polymer based resins. The quality of this interface also affects trapping and recombination of the photogenerated carriers, influencing important imager properties such as sensitivity and image lag.
Pulsed excimer-laser processing of amorphous silicon on non-crystalline substrates allows for the fabrication of high-quality polysilicon thin-film transistors (TFTs). It also provides procedures for doping self-aligned amorphous silicon TFTs. In addition, laser-crystallized polysilicon exhibits some interesting materials properties, such as, large lateral grain growth with a corresponding enhancement in the electron mobility. Under optimized processing conditions, excellent polysilicon TFTs with high mobilities, sharp turn on, low off-state leakage currents and good spatial uniformity have been achieved. These improved parameters, particularly the low off-state leakage currents and good uniformity, enable not only displays but also the moredemanding flat-panel imaging arrays to be fabricated in polysilicon. Results on both polysilicon CMOS circuits and a polysilicon flat-panel imager are presented.
Mycobacterium ulcerans, the organism which causes Buruli
or
Bairnsdale ulcer, has never been
isolated in culture from an environmental sample. Most foci of infection
are in tropical
regions. The authors describe the first 29 cases of M. ulcerans
infection from a new focus on
an island in temperate southern Australia, 1992–5. Cases were
mostly elderly, had
predominantly distal limb lesions and were clustered in a small region
in
the eastern half of the
main town on the island. The authors suspected that an irrigation system
which lay in the
midst of the cluster was a source of infection. Limitation of irrigation
was associated with a
dramatic reduction in the number of new cases. These findings
support the hypothesis that
M. ulcerans has an aquatic reservoir and that persons may be
infected directly or indirectly
by mycobacteria disseminated locally by spray irrigation.
This paper describes our recent research in developing vacuum sublimed lead iodide films for X-ray imaging. Lead iodide films are promising for this application due to their low dark current, high stopping efficiency, reasonably good charge transport, low cost, and relatively easy scale-up. Lead iodide films (up to 5 × 5 cm2 area) have been grown and characterized by measuring their X-ray imaging properties such as spatial resolution, and contrast transfer function. Excellent spatial resolution (> 10 lp/mm with high CTF ≈50%) has been recorded with PbI2 films. Relevant detection properties such as signal amplitude for given X-ray energy has also been measured and was found to be about 10 times larger as compared to standard phosphor screens used for X-ray imaging. Charge transport and timing characteristics of these films have been measured and the results indicate that these films should be capable of real-time operation. Application of these films for X-ray imaging such as mammography, fluoroscopy, and X-ray diffraction is addressed.
The time dependence of the dc conductivity of Li- and Be-doped a-Si:H after thermal quenching is reported. The equilibration kinetics, similar to that observed in substitutionally-doped a-Si:H, is characterized by stretched exponential decays and activated time constants. The equilibration times for Bedoped a-Si:H were too short (< 1 min) for the kinetics of equilibration to be accurately measured. In Li-doped a-Si:H, the equilibration time constants were longer than those in 1% P-doped a-Si:H, which is due to the smaller carrier concentrations in the Li-doped a-Si:H films.
Measurements are reported of metastable defect states in undoped a-Si: H, with the aim of understanding the relation between the different types of metastability. The temperature dependence of the thermal equilibrium defect density agrees well with a proposed thermodynamic model and their relaxation time varies with deposition conditions. The rate of light induced defect creation and annealing in samples deposited at low temperature and with a large initial defect density, decreases progressively as the irreversible defects are removed by annealing.
Results are presented on the properties of a-Si:H thin films deposited with a remote hydrogen plasma. An essential feature of the reactor design is the use of an alumina (rather than quartz) tube to contain the hydrogen plasma for low oxygen contamination of the films. High doping efficiency is demonstrated for both P-and B-doped amorphous films, and the effects of high silane dilution and deposition temperature are illustrated with P-doped amorphous and microcrystalline silicon films.
A double-blind controlled trial of 50% dose reduction in maintenance treatment in stable out-patients with low BPRS scores and good social function shows a significantly higher relapse rate in the low-dose group at 12 months (P < 0.05). After an interval of 24–36 months from dose reduction, 56–76% had experienced a relapse and 76–79% had resumed their former dosage. No clear advantage was shown for the lower dose in either a reduction of side-effects or improved social function, but a reduced prevalence or lower rate of symptom emergence for tardive dyskinesia was suggested.
Recently it has been proposed that solid silicon at the melting temperature is amorphous. There is no known case of a solid for which an amorphous structure is the equilibrium state. Silicon thin films on insulating substrates, when heated radiantly, melt inhomogeneously and provide an accessible high temperature system for a study of a solid coexisting with its melt. Using the intensity, energy distribution and polarization of Raman scattering from silicon lamellae, we have proved that the equilibrium phase is in fact crystalline. Furthermore, we give strong evidence that the solid regions have {100} texture at Tm.