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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.
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.
From its original formulation in 1990 the International Trans-Antarctic Scientific Expedition (ITASE) has had as its primary aim the collection and interpretation of a continent-wide array of environmental parameters assembled through the coordinated efforts of scientists from several nations. ITASE offers the ground-based opportunities of traditional-style traverse travel coupled with the modern technology of GPS, crevasse detecting radar, satellite communications and multidisciplinary research. By operating predominantly in the mode of an oversnow traverse, ITASE offers scientists the opportunity to experience the dynamic range of the Antarctic environment. ITASE also offers an important interactive venue for research similar to that afforded by oceanographic research vessels and large polar field camps, without the cost of the former or the lack of mobility of the latter. More importantly, the combination of disciplines represented by ITASE provides a unique, multidimensional (space and time) view of the ice sheet and its history. ITASE has now collected >20 000km of snow radar, recovered more than 240 firn/ice cores (total length 7000 m), remotely penetrated to ~4000m into the ice sheet, and sampled the atmosphere to heights of >20 km.
An updated compilation of published and new data of major-ion (Ca, Cl, K, Mg, Na, NO3, SO4) and methylsulfonate (MS) concentrations in snow from 520 Antarctic sites is provided by the national ITASE (International Trans-Antarctic Scientific Expedition) programmes of Australia, Brazil, China, Germany, Italy, Japan, Korea, New Zealand, Norway, the United Kingdom, the United States and the national Antarctic programme of Finland. The comparison shows that snow chemistry concentrations vary by up to four orders of magnitude across Antarctica and exhibit distinct geographical patterns. The Antarctic-wide comparison of glaciochemical records provides a unique opportunity to improve our understanding of the fundamental factors that ultimately control the chemistry of snow or ice samples. This paper aims to initiate data compilation and administration in order to provide a framework for facilitation of Antarctic-wide snow chemistry discussions across all ITASE nations and other contributing groups. The data are made available through the ITASE web page (http://www2.umaine.edu/itase/content/syngroups/snowchem.html) and will be updated with new data as they are provided. In addition, recommendations for future research efforts are summarized.
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.
Existing studies reveal that the shape corners of hexagonal fiber affect the degree of constraint on the matrix material. However, none of these studies included the effect of orientation of hexagonal fibers. In this study, a computational micromechanics model of oriented hexagonal fibers in periodic unidirectional composite materials is established for the determination of effective orthotropic elastic properties of the composite. In the present numerical modeling, the representative unit composite cell including the matrix material and the single oriented hexagonal fiber or random oriented hexagonal fibers is solved by micro-scale finite element analysis with different stress loads and periodic displacement boundary conditions, which are applied along the cell boundary to meet the requirement of straight-line constraint during deformation of the cell. Subsequently, the effective elastic properties of the composite are evaluated for periodic regular packing and random packing using the homogenization approach for investigating the influence of unified orientation and random orientation of the hexagonal fibers on the overall elastic properties of the fiber-reinforced composites. The numerical results are verified by comparing with other available results.
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.
At the end of 2013, China reported a countrywide outbreak of measles. From January to May 2014, we investigated the clinical and immunological features of the cases of the outbreak admitted to our hospital. In this study, all 112 inpatients with clinically diagnosed measles were recruited from the 302 Military Hospital of China. The virus was isolated from throat swabs from these patients, and cytokine profiles were examined. By detecting the measles virus of 30 of the 112 patients, we found that this measles outbreak was of the H1 genotype, which is the major strain in China. The rates of complications, specifically pneumonia and liver injury, differed significantly in patients aged <8 months, 8 months to 18 years, and >18 years: pneumonia was more common in children, while liver injury was more common in adults. Pneumonia was a significant independent risk factor affecting measles duration. Compared to healthy subjects, measles patients had fewer CD4+IL-17+, CD4+IFN-γ+, and CD8+IFN-γ+ cells in both the acute and recovery phases. In contrast, measles patients in the acute phase had more CD8+IL-22+ cells than those in recovery or healthy subjects. We recommend that future studies focus on the age-related distribution of pneumonia and liver injury as measles-related complications as well as the association between immunological markers and measles prognosis.
In this paper, we consider a compilation of 55 objects with known superluminal motions (SM), and whose flux density (X-ray, optical, radio), core dominance parameter (R), superluminal velocity, and radio Doppler factor (δR) are known. Our study shows that SM is consistent with the beaming model, and the relation
is reasonable. The statistical correlation between superluminal velocity and redshift is a result of selection and the statistical correlation between R and brightness temperature (Tob) is actually a reflection of the correlations between δ, R, and Tob for objects with SM. Up to now, 59 objects have been reported to have SM, but for reasons discussed elsewhere (Vermeulen & Cohen 1994), only 55 are considered here.
Legionnaires’ disease (LD) is a globally distributed systemic infectious disease. The burden of LD in many regions is still unclear, especially in Asian countries including China. A survey of Legionella infection using real-time PCR and nested sequence-based typing (SBT) was performed in two hospitals in Shanghai, China. A total of 265 bronchoalveolar lavage fluid (BALF) specimens were collected from hospital A between January 2012 and December 2013, and 359 sputum specimens were collected from hospital B throughout 2012. A total of 71 specimens were positive for Legionella according to real-time PCR focusing on the 5S rRNA gene. Seventy of these specimens were identified as Legionella pneumophila as a result of real-time PCR amplification of the dotA gene. Results of nested SBT revealed high genetic polymorphism in these L. pneumophila and ST1 was the predominant sequence type. These data revealed that the burden of LD in China is much greater than that recognized previously, and real-time PCR may be a suitable monitoring technology for LD in large sample surveys in regions lacking the economic and technical resources to perform other methods, such as urinary antigen tests and culture methods.
Three groups of genes, Vrn, Ppd and Eps, control life-cycle duration in wheat (Triticum aestivum L.). The duration of a developmental phase between two stages is important for freezing resistance, heading time, anthesis and ripening date as well as yield component generation. The aim of the current study was to assess the effect of Vrn-D1 on wheat development. The vernalization genes Vrn-A1, -B1, -D1, -B3, photoperiod gene Ppd-1 and candidate genes Mot1 and FtsH4 for Eps in ‘G883’, ‘Pumai 9’ and their offspring, a group of sister lines (SLs) derived from an advanced generation, were genotyped using specific molecular markers. All detected loci were the same in the SLs and their parents except the Vrn-D1 locus. Three developmental traits, spike differentiation process, heading date and final leaf number on the main stem, were characterized in three sowing date treatments in the field. When temperatures increased, cultivars/lines carrying the dominant Vrn-D1 gene entered each spike differentiation process faster than those with the recessive vrn-D1 in the same sowing date treatment. Lines carrying Vrn-D1 had smaller final leaf number on the main stem than those with vrn-D1, and the heading dates of the former were earlier than those of the latter, especially in the fourth treatment, sown on 23 February 2012. These data suggest that Vrn-D1 confers a spring habit on wheat and the vrn-D1 confers a cold, hardy winter habit. The Vrn-D1 alleles play very important roles in semi-winter and tender spring wheat cultivars, especially in warm weather in Henan, China. Regulating developmental traits by tracing Vrn-D1 and getting an ideal combination of Vrn alleles to accommodate different wheat zones is a key role for future wheat molecular breeding.
We investigated the prevalence of β-lactamase genes and plasmid-mediated quinolone resistance (PMQR) determinants in 51 carbapenem-resistant Enterobacteriaceae (CRE) from five teaching hospitals in central China. The prevalence of carbapenem resistance in Enterobacteriaceae was 1·0% (51/5012). Of 51 CRE, 31 (60·8%) isolates were positive for one tested carbapenemase gene, while 10 (19·6%) were simultaneously positive for two tested carbapenemase genes. The positive rates of blaKPC-2, blaNDM-1, blaIMP-4, blaIMP-26 and blaIMP-8 were 54·9%, 17·6%, 11·8%, 11·8% and 3·9%, respectively. Of 10 CRE with two carbapenemase genes, three, five, one and one were positive for blaKPC-2 and blaIMP-4, blaKPC-2 and blaIMP-26, blaKPC-2 and blaIMP-8, and blaKPC-2 and blaNDM-1, respectively. Eight of nine blaNDM-1-positive isolates lacked carbapenemases by the modified Hodge test, while 27/28 isolates harbouring blaKPC-2 were positive for carbapenemases determined by this test; 41·2% of the CRE-positive isolates also harboured ESBL genes in various combinations (three and two positive for blaKPC-2 also carried blaDHA-1 and blaCMY-2). The positive rates of qnrS1, qnrA1, qnrB and aac-(6/)-Ib-cr in CRE were 25·5%, 9·8%, 23·5% and 15·7%, respectively. In particular, 7/9 isolates harbouring blaNDM-1 were positive for these quinolone resistance genes, of which five carried qnrS1 and two carried qnrS1 and qnrB4. All but two of 29 Klebsiella pneumoniae isolates were grouped into 20 clonal clusters by PFGE, with the predominant cluster accounting for four blaKPC-2-positive isolates distributed in the same hospital. We conclude that there is a high prevalence of blaNDM-1 and PMQR determinants in CRE isolates in central China. Multiple resistance determinants in various combinations co-exist in these strains and we report for the first time the co-existence of blaKPC-2 and blaIMP-26 in a strain of Klebsiella oxytoca.
In this paper, a new algorithm is developed based on the homogenization method integrating with the newly developed Hybrid Treffe FEM (HT-FEM) and Hybrid Fundamental Solution based FEM (HFS-FEM). The algorithm can be used to evaluate effective elastic properties of heterogeneous composites. The representative volume element (RVE) of fiber reinforced composites with periodic boundary conditions is introduced and used in our numerical analysis. The proposed algorithm is assessed through two numerical examples with different mesh density and element geometry and used to investigate the effect of fiber volume fraction, fiber shape and configuration on the effective properties of composites. It is found that the proposed algorithm is insensitive to element geometry and mesh density compared with the traditional FEM (e.g. ABAQUS). The numerical results indicate that the HT-FEM and HFS-FEM are promising in micromechanical modeling of heterogeneous materials containing inclusions of various shapes and distributions. They are potential to be used for future application in multiscale simulation.
We have used a hydrogel templating technique followed by the subsequent evaporation of water present to fabricate porous cement and porous PDMS composites, and we have analyzed their sound absorption properties. All experiments were carried out with hydrogel slurries of broad bead size distributions. Porous PDMS and cement composites were produced with porosities of up to 80% and 70%, respectively. Scanning electron microscope analysis shows fibrous domains within the voids created by the hydrogel in the cement samples and open pore network in the PDMS composites of initial hydrogel content higher than 70 vol%. Sound absorption was improved with respect to control nonporous samples in all composites with porosities higher than 60 vol%, where an open pore structure was formed. The porous PDMS and porous cement produced by this method show better sound absorption at 200–400 Hz and 1200–1800 Hz frequency ranges when compared with the sound absorption in the intermediate frequencies range between 400 and 1000 Hz.
We studied seasonal patterns of swine hepatitis E virus (HEV) infection in China. From 2008 to 2011, 4200 swine bile specimens were collected for the detection of HEV RNA. A total of 92/2400 (3·83%) specimens in eastern China and 47/1800 (2·61%) specimens in southwestern China were positive for HEV. Seasonal patterns differing by geographical area were suggested. In eastern China, the major peak of HEV RNA prevalence was during March–April, with a minor peak during September–October, and a dip during July–August. In southwestern China, the peak was during September–October and the dip during March–April. The majority of subtype 4a cases (63/82, 76·83%) were detected in the first half of the year, while the majority of subtype 4b cases (26/29, 89·66%) were concentrated in the second half of the year, suggesting that different subtypes contribute to different peaks. Our results indicate that the distribution of HEV subtypes is associated with seasonal patterns.
An adaptive algorithm is presented for the wavelength calibration of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST). The new algorithm can identify emission lines of calibration lamp without manual interaction and then fit relationship between the pixel positions and the wavelengths by utilizing a polynomial function. In this study, experiments are performed both on the actual data observed by LAMOST and the simulated data to analyze the accuracy and the robustness.The experimental results show that the proposed automatic algorithm can perform the lines identification exactly and acquire the wavelength solution accurately. Thus, an applicable approach is provided for the wavelength calibration of LAMOST.
In this paper, we give a general proof on convergence estimates for some regularization methods to solve a Cauchy problem for the Laplace equation in a rectangular domain. The regularization methods we considered are: a non-local boundary value problem method, a boundary Tikhonov regularization method and a generalized method. Based on the conditional stability estimates, the convergence estimates for various regularization methods are easily obtained under the simple verifications of some conditions. Numerical results for one example show that the proposed numerical methods are effective and stable.