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Klebsiella pneumoniae is a common pathogen associated with nosocomial infections and is characterised serologically by capsular polysaccharide (K) and lipopolysaccharide O antigens. We surveyed a total of 348 non-duplicate K. pneumoniae clinical isolates collected over a 1-year period in a tertiary care hospital, and determined their O and K serotypes by sequencing of the wbb Y and wzi gene loci, respectively. Isolates were also screened for antimicrobial resistance and hypervirulent phenotypes; 94 (27.0%) were identified as carbapenem-resistant (CRKP) and 110 (31.6%) as hypervirulent (hvKP). isolates fell into 58 K, and six O types, with 92.0% and 94.2% typeability, respectively. The predominant K types were K14K64 (16.38%), K1 (14.66%), K2 (8.05%) and K57 (5.46%), while O1 (46%), O2a (27.9%) and O3 (11.8%) were the most common. CRKP and hvKP strains had different serotype distributions with O2a:K14K64 (41.0%) being the most frequent among CRKP, and O1:K1 (26.4%) and O1:K2 (17.3%) among hvKP strains. Serotyping by gene sequencing proved to be a useful tool to inform the clinical epidemiology of K. pneumoniae infections and provides valuable data relevant to vaccine design.
Uncertainty in the critical amplification factor (
) of the
transition model is used to approximate the uncertainty in the surface and flow quality of natural laminar flow (NLF) aerofoils. The uncertainty in
is represented by a negative half-normal probability distribution that descends from the largest
achievable with an ideal surface and flow quality. The uncertainty in various aerodynamic coefficients due to the uncertainty in
is quantified using the weighted mean and standard deviation of flow solutions run at different
values. The uncertainty in the aerofoil performance is assessed using this methodology. It is found that the standard deviation of the aerofoil performance due to the uncertainty in
is largest when the transition location is most sensitive to changes in the lift coefficient at the ideal
. Robust shape optimisation is also carried out to improve the mean performance and reduce the standard deviation of the performance with uncertainty in
. This is found to be effective at producing aerofoils with a larger amount of laminar flow that are less sensitivity to uncertainty in
. A trade-off is observed between the mean performance and the standard deviation of the performance. It is also found that reducing the standard deviation of the performance at one Mach number or lift coefficient design point can cause an increase in the standard deviation off-design.
Achieving control over the morphology of conjugated polymer (CP) blends at nanoscale is crucial for enhancing their performances in diverse organic optoelectronic devices, including thin film transistors, photovoltaics, and light emitting diodes. However, the complex CP chemical structures and intramolecular interactions often make such control difficult to implement. We demonstrate here that cooperative combination of non-covalent interactions, including hydrogen bonding, coordination interactions, and π-π interactions, etc., can be used to effectively define the morphology of CP blend films, in particular being able to achieve accurate spatial arrangement of nanoparticles within CP nanostructures. Through UV-vis absorption spectroscopy and transmission electron microscopy, we show strong attachment of fullerene molecules, CdSe quantum dots, and iron oxide nanoparticles, onto well-defined CP nanofibers. The resulting core/shell hybrid nanofibers exhibit well-defined donor/acceptor interface when employed in photovoltaic devices, which also contributes to enhanced charge separation and transport. These findings provide a facile new methodology of improving CP/nanoparticle interfacial properties and controlling blend morphology. The generality of this methodology demonstrated in current studies points to a new way of designing hybrid materials based on organic polymers and inorganic nanoparticles towards applications in modern electronic devices.
In recent years, investigations of the phase transition behavior of semiconducting nanoparticles under high pressure has attracted increasing attention due to their potential applications in sensors, electronics, and optics. However, current understanding of how the size of nanoparticles influences this pressure-dependent property is somewhat lacking. In particular, phase behaviors of semiconducting CdS nanoparticles under high pressure have not been extensively reported. Therefore, in this work, CdS nanoparticles of different sizes are used as a model system to investigate particle size effects on high-pressure-induced phase transition behaviors. In particular, 7.5, 10.6, and 39.7 nm spherical CdS nanoparticles are synthesized and subjected to controlled high pressures up to 15 GPa in a diamond anvil cell. Analysis of all three nanoparticles using in-situ synchrotron wide-angle X-ray scattering (WAXS) data shows that phase transitions from wurtzite to rocksalt occur at higher pressures than for bulk material. Bulk modulus calculations not only show that the wurtzite CdS nanomaterial is more compressible than rocksalt, but also that the compressibility of CdS nanoparticles depends on their particle size. Furthermore, sintering of spherical nanoparticles into nanorods was observed for the 7.5 nm CdS nanoparticles. Our results provide new insights into the fundamental properties of nanoparticles under high pressure that will inform designs of new nanomaterial structures for emerging applications.
Resistant starch (RS) was recently approved to exert a powerful influence on gut health, but the effect of RS on the caecal barrier function in meat ducks has not been well defined. Thus, the effect of raw potato starch (RPS), a widely adopted RS material, on microbial composition and barrier function of caecum for meat ducks was determined. A total of 360 Cherry Valley male ducks of 1-d-old were randomly divided and fed diets with 0 (control), 12, or 24 % RPS for 35 d. Diets supplemented with RPS significantly elevated villus height and villus height:crypt depth ratio in the caecum. The 16S rRNA sequence analysis indicated that the diet with 12 % RPS had a higher relative abundance of Firmicutes and the butyrate-producing bacteria Faecalibacterium, Subdoligranulum, and Erysipelatoclostridium were enriched in all diets. Lactobacillus and Bifidobacterium were significantly increased in the 24 % RPS diet v. the control diet. When compared with the control diet, the diet with 12 % RPS was also found to notably increase acetate, propionate and butyrate contents and up-regulated barrier-related genes including claudin-1, zonula occludens-1, mucin-2 and proglucagon in the caecum. Furthermore, the addition of 12 % RPS significantly reduced plasma TNF-α, IL-1β and endotoxin concentrations. These data revealed that diets supplemented with 12 % RPS partially improved caecal barrier function in meat ducks by enhancing intestinal morphology and barrier markers expression, modulating the microbiota composition and attenuating inflammatory markers.
The National Institute for Health and Care Excellence referral guidelines prompting urgent two-week referrals were updated in 2015. Additional symptoms with a lower threshold of 3 per cent positive predictive values were integrated. This study aimed to examine whether current pan-London urgent referral guidelines for suspected head and neck cancer lead to efficient and accurate referrals by assessing frequency of presenting symptoms and risk factors, and examining their correlation with positive cancer diagnoses.
The risk factors and symptoms of 984 consecutive patients (over a six-month period in 2016) were collected retrospectively from urgent referral letters to University College London Hospital for suspected head and neck cancer.
Only 37 referrals (3.76 per cent) resulted in a head and neck cancer diagnosis. Four of the 23 recommended symptoms demonstrated statistically significant results. Nine of the 23 symptoms had a positive predictive value of over 3 per cent.
The findings indicate that the current referral guidelines are not effective at detecting patients with cancer. Detection rates have decreased from 10–15 per cent to 3.76 per cent. A review of the current head and neck cancer referral guidelines is recommended, along with further data collection for comparison.
To characterise the dissemination patterns of uropathogenic Escherichia coli (UPEC) in a community, we conducted a study utilising molecular and fundamental descriptive epidemiology. The subjects, consisted of women having community-acquired acute urinary tract infection (UTI), were enrolled in the study from 2011 to 2012. UPEC isolates were subjected to antibacterial-susceptibility testing, O serogrouping, phylotyping, multilocus-sequence typing with phylogenetic-tree analysis and pulsed-field-gel electrophoresis (PFGE). From the 209 unique positive urinary samples 166 UPEC were isolated, of which 129 were fully susceptible to the tested antibiotics. Of the 53 sequence types (STs), the four most prevalent STs (ST95, ST131, ST73 and ST357) accounted for 60% of all UPEC strains. Antimicrobial resistance was less frequently observed for ST95 and ST73 than for the others. A majority of rare STs and a few common STs constituted the diversity pattern within the population structure, which was composed of the two phylogenetically distinct clades. Eleven genetically closely related groups were determined by PFGE, which accounted for 42 of the 166 UPEC isolates, without overt geo-temporal clustering. Our results indicate that a few major lineages of UPEC, selected by unidentified factors, are disseminated in this community and contribute to a large fraction of acute UTIs.
To examine the diagnostic value of hyoid cephalometrics in predicting retroglossal obstruction severity in patients with obstructive sleep apnoea hypopnea syndrome.
Ninety-six obstructive sleep apnoea hypopnea syndrome patients diagnosed by polysomnography were recruited. Polysomnography was repeated with a nasopharyngeal tube after eliminating rhinal and palatopharyngeal obstruction. Cervical vertebra lateral films and hyoid cephalometric measurements were obtained, including the distances of the hyoid to the: mental tubercle, prevertebral plane, mental tubercle coronal plane and mental tubercle horizontal plane.
The apnoea-hypopnoea index for nasopharyngeal tube polysomnography was significantly correlated with distances from the hyoid to: prevertebral plane (r = 0.350), coronal plane (r = 0.477), horizontal plane (r = 0.529) and mental tubercle (r = 0.560). It was strongly correlated with the hyoid to mental tubercle distance/hyoid to prevertebral plane distance value (r = 0.683), and (hyoid to coronal plane distance plus hyoid to horizontal plane distance)/hyoid to prevertebral plane distance value (r = 0.675).
Obstructive sleep apnoea hypopnea syndrome patients with longer hyoid to mental tubercle distances, and/or more inferior and posterior hyoid bone position, are more prone to retroglossal stenosis and obstruction. Hyoid cephalometrics are valuable for predicting retroglossal obstruction severity.
The six LIGO detections of merging black holes (BHs) allowed to infer slow spin values for the two pre-merging BHs. The three cases where the spins of the BHs can be determined in high-mass X-ray binaries (HMXBs) show that those BHs have high spin values. We discuss here scenarios explaining these differences in spin properties in these two classes of object.
The Working Party has produced this report in order to prompt readers to engage at an early stage in InsurTech projects, through considering (i) the full range of risks associated with InsurTech developments, (ii) the lifecycle of an InsurTech venture and how any risk considerations may vary over this lifecycle and (iii) the extent to which InsurTech ventures align with risk strategy and risk appetite.
The report contains practical guidance for actuaries, risk professionals, insurance companies and their Boards on these considerations, and can be used to facilitate appropriate questioning, to help ensure that InsurTech-related business decisions are fully cognisant of the risk management issues and to help ensure the success of projects.
The Working Party developed this guidance having carried out an industry survey on a number of risk management topics relating to InsurTech, as well as having carried out interviews with a number of relevant senior stakeholders across the insurance industry, in order to better understand current sentiment and how risk management plays a part when considering opportunities in InsurTech. The Working Party views on the findings from these activities are summarised in the report.
Knowledge, attitudes and practices (KAP) of the population regarding severe fever with thrombocytopenia syndrome (SFTS) in endemic areas of Lu'an in China were assessed before and after an intervention programme. The pre-intervention phase was conducted using a sample of 425 participants from the 12 selected villages with the highest rates of endemic SFTS infection. A predesigned interview questionnaire was used to assess KAP. Subsequently, an intervention programme was designed and applied in the selected villages. KAP was re-assessed for each population in the selected villages using the same interview questionnaire. Following 2 months of the programme, 339 participants had completed the re-assessed survey. The impact of the intervention programme was evaluated using suitable statistical methods. A significant increase in the KAP and total KAP scores was noted following the intervention programme, whereas the proportion of correct knowledge, the positive attitudes and the effective practices toward SFTS of respondents increased significantly. The intervention programme was effective in improving KAP level of SFTS in populations that were resident in endemic areas.
Piglets are characteristically cold intolerant and thus susceptible to high mortality. However, browning of white adipose tissue (WAT) can induce non-shivering thermogenesis as a potential strategy to facilitate the animal’s response to cold. Whether cold exposure can induce browning of subcutaneous WAT (sWAT) in piglets in a similar manner as it can in humans remains largely unknown. In this study, piglets were exposed to acute cold (4°C, 10 h) or chronic cold exposure (8°C, 15 days), and the genes and proteins of uncoupling protein 1 (UCP1)-dependent and independent thermogenesis, mitochondrial biogenesis, lipogenic and lipolytic processes were analysed. Interestingly, acute cold exposure induced browning of porcine sWAT, smaller adipocytes and the upregulated expression of UCP1, PGC1α, PGC1β, C/EBPβ, Cidea, UCP3, CKMT1 and PM20D1. Conversely, chronic cold exposure impaired the browning process, reduced mitochondrial numbers and the expression of browning markers, including UCP1, PGC1α and PRDM16. The present study demonstrated that acute cold exposure (but not chronic cold exposure) induces porcine sWAT browning. Thus, browning of porcine sWAT could be a novel strategy to balance the body temperature of piglets, and thus could be protective against cold exposure.
We investigated the first presence of qnrA among Shigella sonnei clinical isolates in Jiangsu Province, China. The qnrA-positive isolates coexisted with the mutation in gyrA at codon 83, these isolates were resistant to nalidixic acid and 22·2% (2 of 9) of them were resistant to norfloxacin.
Tigers are among the most at-risk large carnivores and the South China tiger is the most threatened tiger subspecies. Reintroduction programmes are one strategy to re-establishing extirpated populations. China is committed to restoring wild South China tigers, but uncertainty remains about factors constraining these efforts. The aim of this study was to query conservation and reintroduction professionals about their attitudes and concerns and to provide guidance regarding a possible tiger reintroduction effort in South Central China. We carried out a global survey of 287 scholars and practitioners involved with wildlife reintroduction and conservation. We received responses from 68 (23.7%) respondents. More than 70% supported a potential South China tiger reintroduction effort, but many expressed concerns over planning and implementation, adherence to International Union for Conservation of Nature reintroduction guidelines and elimination of underlying threats. Respondents generally believed that China has the capacity to carry out such a programme, but may not have the experience or socio-political environment to address the issues facing human populations; 62% of respondents suggested a plausible release site should be greater than 2000 km2. To our knowledge, this is the first survey related to a potential large carnivore reintroduction programme in Asia; it has implications for future reintroduction and recovery programmes in Asia and globally.
This study aimed to develop a simple and accurate method to diagnose paediatric obstructive sleep apnoea hypopnea syndrome.
A total of 311 children with suspected paediatric obstructive sleep apnoea hypopnea syndrome were included in the study. Multiple clinical parameters, including sex, age, body mass index, history of snoring or gasping, history of nasal obstruction, history of running nose, palatine tonsil size, adenoid to nasopharynx ratio, and tympanogram type, were compared with polysomnography results using relevant correlation and regression analyses. A diagnostic scale was established using the regression equation and the correlation between the polysomnography result and scale result was determined.
The apnoea–hypopnea index correlated significantly with a history of snoring or gasping, palatine tonsil size, and tympanogram type. Stepwise logistic regression analysis revealed that the polysomnography result correlated significantly with a history of snoring or gasping, palatine tonsil size, and the adenoid to nasopharynx ratio. The percentage correlation between the scale and polysomnography results was 77.8 per cent.
The diagnostic scale can be used to diagnose paediatric obstructive sleep apnoea hypopnea syndrome for clinical application when polysomnography cannot be performed. However, it is not suitable for assessing the severity of paediatric obstructive sleep apnoea hypopnea syndrome.
As a disconnection syndrome, schizophrenia has shown impaired resting-state functional connectivity (rsFC) in the orbitofrontal cortex (OFC); however, the OFC is a rather heterogeneous region and the rsFC changes in the OFC subregions remain unknown.
A total of 98 schizophrenia patients and 102 healthy controls underwent resting-state functional MRI using a sensitivity-encoded spiral-in imaging sequence (SENSE-SPIRAL) to reduce susceptibility-induced signal loss and distortion. The OFC subregions were defined according to a previous parcellation study that divided the OFC into the anterior (OFCa), medial (OFCm), posterior (OFCp), intermediate (OFCi), and lateral (OFCl) subregions. The rsFC was compared using two-way repeated-measures ANOVA.
Whether or not global signal regression, compared with healthy controls, schizophrenia patients consistently exhibited decreased rsFC between the left OFCi and the left middle temporal gyrus and the right middle frontal gyrus (MFG), between the right OFCi and the right MFG and the left inferior frontal gyrus, between the right OFCm and the middle cingulate cortex and the left Rolandic operculum. These rsFC changes still remained significant even after cortical atrophy correction.
These findings suggest a selective functional disconnection of the OFC subregions in schizophrenia, and provide more precise information about the functional disconnections of the OFC in this disorder.
Failure of metallic materials due to plastic and/or creep deformation occur by the emergence of necking, microvoids, and cracks at heterogeneities in the material microstructure. While many traditional deformation modeling approaches have difficulty capturing these emergent phenomena, the discrete element method (DEM) has proven effective for the simulation of materials whose properties and response vary over multiple spatial scales, e.g., bulk granular materials. The DEM framework inherently provides a mesoscale simulation approach that can be used to model macroscopic response of a microscopically diverse system. DEM naturally captures the heterogeneity and geometric frustration inherent to deformation processes. While DEM has recently been adapted successfully for modeling the fracture of brittle solids, to date it has not been used for simulating metal deformation. In this paper, we present our progress in reformulating DEM to model the key elastic and plastic deformation characteristics of FCC polycrystals to create an entirely new crystal plasticity modeling methodology well-suited for the incorporation of heterogeneities and simulation of emergent phenomena.
Psychosocial therapy after deliberate self-harm might be associated with reduced risk of specific causes of death.
In this matched cohort study, we included patients, who after an episode of deliberate self-harm received psychosocial therapy at a Suicide Prevention Clinic in Denmark between 1992 and 2010. We used propensity score matching in a 1:3 ratio to select a comparison group from 59 046 individuals who received standard care. National Danish registers supplied data on specific causes of death over a 20-year follow-up period.
At the end of follow-up, 391 (6.9%) of 5678 patients in the psychosocial therapy group had died, compared with 1736 (10.2%) of 17 034 patients in the matched comparison group. Lower odds ratios of dying by mental or behavioural disorders [0.54, 95% confidence interval (CI) 0.37–0.79], alcohol-related causes (0.63, 95% CI 0.50–0.80) and other diseases and medical conditions (0.61, 95% CI 0.49–0.77) were noted in the psychosocial therapy group. Also, we found a reduced risk of dying by suicide as well as other external causes, however, not by neoplasms and circulatory system diseases. Numbers needed to treat were 212.9 (95% CI 139.5–448.4) for mental or behavioural disorders as a cause of death, 111.1 (95% CI 79.2–210.5) for alcohol-related causes and 96.8 (95% CI 69.1–161.8) for other diseases and medical conditions.
Our findings indicate that psychosocial therapy after deliberate self-harm might reduce long-term risk of death from select medical conditions and external causes. These promising results should be tested in a randomized design.