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Beijing–Tianjin–Hebei is the largest urban agglomeration in northern China, but the spatiotemporal patterns and risk factors concerning hepatitis B virus (HBV) incidence in this area have been unclear. The present study aimed to reveal the spatiotemporal epidemiological features of HBV infection and quantify the association between HBV infection and socio-economic risk factors. The data on HBV cases in Beijing–Tianjin–Hebei from 2007 to 2012 was collected for each county. The Bayesian space–time hierarchy model and the GeoDetector method were used to reveal spatiotemporal patterns and detect risk factors. High-risk regions were mainly distributed in the underdeveloped rural areas in the north and mid-south of the study region, while low-risk regions were mainly distributed in the urban and western areas. The HBV annual incidence rate decreased substantially over the 6-year period, dropping from 7.34/105 to 5.51/105. Compared with this overall trend, 38.5% of high-risk counties showed a faster decrease, and 35.9% of high-risk counties exhibited a slower decrease. Meanwhile, 29.7% of low-risk counties had a faster decrease, and 44.6% of low-risk counties exhibited a slower decrease. Socio-economic factors were strongly associated with the spatiotemporal patterns and variation. The population density and gross domestic product per capita were negatively associated with HBV transmission, with determinant powers of 0.17 and 0.12, respectively. The proportion of primary industry and the number of healthcare workers were positively associated with the disease incidence, with determinant powers of 0.11 and 0.8, respectively. The interactive effect between population density and the other factors exerted a greater influence on HBV transmission than that of these factors measured independently.
This study investigated Echinococcus genotypes in patients with hydatidosis that reside in Inner Mongolia, Tibet or Qinghai Province by partially sequencing the cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase 1 (nad1) genes. Cyst fluids were collected from 23 patients with hydatidosis and DNA was extracted. Portions of the cox1 and nad1 genes were amplified and subsequently sequenced. Sequencing analysis determined that one of the isolates contained Echinococcus multilocularis, and the other 22 isolates contained E. granulosus sensu lato. The isolates were then further classified based on genotype, and E. granulosus sensu stricto (s.s.) G1 (n = 20), E. granulosus s.s. G3 (n = 1) and E. canadensis G6/7 (n = 1) were identified. Additionally, the sequences were concatenated (pcox1 + pnad1) and 11 haplotypes were identified among the E. granulosus s.s. isolates (G1 and G3), with a shared common haplotype (H1) identified. Overall, these findings provide further understanding of the genetic patterns of Echinococcus in western and northern China.
A systematic review was conducted to investigate the effectiveness of fibroblast growth factor-2 on the regeneration of tympanic membrane perforation.
The PubMed database was searched for relevant studies. Experimental studies, human randomised controlled trials, prospective single-arm studies and retrospective studies reporting acute and chronic tympanic membrane perforations in relation to two healing outcomes (success rate and closure time), were selected.
All 11 clinical studies investigating the effect of fibroblast growth factor-2 on traumatic tympanic membrane perforations in humans reported a success rate of 89.3–100 per cent, with a closure time of around 2 weeks. Three studies of fibroblast growth factor-2 combined with Gelfoam showed that the success rate of chronic tympanic membrane perforation was 83–98.1 per cent in the fibroblast growth factor-2 group, but 10 per cent in the gelatine sponge groups.
Fibroblast growth factor-2 with or without biological material patching promotes regeneration in cases of acute and chronic tympanic membrane perforation, and is safe and efficient. However, the best dosage, application time and administration pathway of fibroblast growth factor-2 are still to be elucidated.
Influenza is a long-standing public health concern, but its transmission remains poorly understood. To have a better knowledge of influenza transmission, we carried out a detailed modelling investigation in a nosocomial influenza outbreak in Hong Kong. We identified three hypothesised transmission modes between index patient and other inpatients based on the long-range airborne and fomite routes. We considered three kinds of healthcare workers’ routine round pathways in 1140 scenarios with various values of important parameters. In each scenario, we used a multi-agent modelling framework to estimate the infection risk for each hypothesis and conducted least-squares fitting to evaluate the hypotheses by comparing the distribution of the infection risk with that of the attack rates. Amongst the hypotheses tested in the 1140 scenarios, the prediction of modes involving the long-range airborne route fit better with the attack rates, and that of the two-route transmission mode had the best fit, with the long-range airborne route contributing about 94% and the fomite route contributing 6% to the infections. Under the assumed conditions, the influenza virus was likely to have spread via a combined long-range airborne and fomite routes, with the former predominant and the latter negligible.
Plant height and lodging resistance can affect rice yield significantly, but these traits have always conflicted in crop cultivation and breeding. The current study aimed to establish a rapid and accurate plant type evaluation mechanism to provide a basis for breeding tall but lodging-resistant super rice varieties. A comprehensive approach integrating plant anatomy and histochemistry was used to investigate variations in flexural strength (a material property, defined as the stress in a material just before it yields in a flexure test) of the rice stem and the lodging index of 15 rice accessions at different growth stages to understand trends in these parameters and the potential factors influencing them. Rice stem anatomical structure was observed and the lignin content the cell wall was determined at different developmental stages. Three rice lodging evaluation models were established using correlation analysis, multivariate regression and artificial radial basis function (RBF) neural network analysis, and the results were compared to identify the most suitable model for predicting optimal rice plant types. Among the three evaluation methods, the mean residual and relative prediction errors were lowest using the RBF network, indicating that it was highly accurate and robust and could be used to establish a mathematical model of the morphological characteristics and lodging resistance of rice to identify optimal varieties.
This paper reports the measurement of the energy loss of protons at the energy of 100 keV penetrating a partially ionized hydrogen plasma. The plasma of ne ≈ 1015–16 cm−3; Te ≈ 1–2 eV and lifetime of about 8 µs is created by the hydrogen gas discharge. The experimental results show an increase of a factor of 2.8 in the energy loss, which are in good agreement with the Bethe, Standard Stopping Model, Li–Petrasso and Vlasov models’ predictions within the error limit. The Bethe–Bloch Coulomb logarithm term is found to increase by a factor of 4.0 for free electrons as compared with the situation where bound electrons prevail. The potential application of protons energy loss for diagnosing the electron density in plasma is proposed too.
Increasing evidence has demonstrated that the environmental conditions experienced by parents can shape offspring phenotypes. Here, we examined the effects of the photoperiod and temperature experienced by parents on the incidence of diapause in their progeny in the cabbage beetle, Colaphellus bowringi, using three experiments. The first experiment examined parental diapause incidence under different photoperiods at 25°C and the incidence of diapause in progeny from both non-diapausing and diapausing parents under the same rearing conditions. The results revealed that the incidence of diapause among progeny was exactly opposite to that of their parents, i.e., higher parental diapause incidence led to lower progeny diapause incidence, showing a negative relationship in diapause incidence between the parental generation and the progeny generation. The incidence of diapause among progeny produced by diapausing parents was higher than that in progeny produced by non-diapausing parents. The second experiment examined parental diapause incidence at different temperatures under LD 12:12 and the incidence of diapause in progeny from both non-diapausing and diapausing parents under the same rearing conditions. Similarly, the incidence of diapause in progeny was also opposite to that of their parents. However, the incidence of diapause in progeny produced by non-diapausing parents was different from that in progeny produced by diapausing parents. In the third experiment, naturally diapausing adults were maintained at a constant temperature of 9, 28°C or the mean daily summer temperature of 27.84°C under continuous darkness for 3 months of dormancy. After dormancy, the progeny of these post-diapause parents were reared under different photoperiods at 25°C. The results showed that the incidence of diapause among progeny was higher when their parents experienced high temperatures than when they experienced low temperatures. All results demonstrate that the photoperiod and temperature experienced by parents may significantly affect the diapause incidence among progeny.
Little is known about the combined use of benzodiazepines and antidepressants in older psychiatric patients. This study examined the prescription pattern of concurrent benzodiazepines in older adults treated with antidepressants in Asia, and explored its demographic and clinical correlates.
The data of 955 older adults with any type of psychiatric disorders were extracted from the database of the Research on Asian Psychotropic Prescription Patterns for Antidepressants (REAP-AD) project. Demographic and clinical characteristics were recorded using a standardized protocol and data collection procedure. Both univariate and multiple logistic regression analyses were performed.
The proportion of benzodiazepine and antidepressant combination in this cohort was 44.3%. Multiple logistic regression analysis revealed that higher doses of antidepressants, younger age (<65 years), inpatients, public hospital, major comorbid medical conditions, antidepressant types, and country/territory were significantly associated with more frequent co-prescription of benzodiazepines and antidepressants.
Nearly, half of the older adults treated with antidepressants in Asia are prescribed concurrent benzodiazepines. Given the potentially adverse effects of benzodiazepines, the rationale of benzodiazepines and antidepressants co-prescription needs to be revisited.
The origins and phylogeny of different sheep breeds has been widely studied using polymorphisms within the mitochondrial hypervariable region. However, little is known about the mitochondrial DNA (mtDNA) content and phylogeny based on mtDNA protein-coding genes. In this study, we assessed the phylogeny and copy number of the mtDNA in eight indigenous (population size, n=184) and three introduced (n=66) sheep breeds in China based on five mitochondrial coding genes (COX1, COX2, ATP8, ATP6 and COX3). The mean haplotype and nucleotide diversities were 0.944 and 0.00322, respectively. We identified a correlation between the lineages distribution and the genetic distance, whereby Valley-type Tibetan sheep had a closer genetic relationship with introduced breeds (Dorper, Poll Dorset and Suffolk) than with other indigenous breeds. Similarly, the Median-joining profile of haplotypes revealed the distribution of clusters according to genetic differences. Moreover, copy number analysis based on the five mitochondrial coding genes was affected by the genetic distance combining with genetic phylogeny; we also identified obvious non-synonymous mutations in ATP6 between the different levels of copy number expressions. These results imply that differences in mitogenomic compositions resulting from geographical separation lead to differences in mitochondrial function.
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.
By introducing the concept of forming springback anti-coupled systems and considering the influence of the self damping effect, meanwhile establishing higher-order geometrical nonlinear equation of a high strength and low alloy (HSLA) steel plate, then a set of nonlinear dynamic springback governing equations of the plate are obtained. The finite difference method, Newmark method and iterative method are applied to solve the whole problem. Numerical results denote that the boundary conditions, thickness-length ratio of the plate and initial impact velocity of the impactor have great influence on the springback amount of the rectangular HSLA steel plate, besides the natural frequency is affected a lot by the boundary conditions and thickness-length ratio. The effect of higher-order geometrical nonlinearity on the springback amount of the plate can be ignored, considering the first-order geometrical nonlinearity is enough accurate for such similar nonlinear dynamic problems.
Hand, foot, and mouth disease (HFMD) is highly prevalent in China, and more efficient methods of epidemic detection and early warning need to be developed to augment traditional surveillance systems. In this paper, a method that uses Baidu search queries to track and predict HFMD epidemics is presented, and the outbreaks of HFMD in China during the 60-month period from January 2011 to December 2015 are predicted. The Pearson correlation coefficient (R) of the predictive model and the mean absolute percentage errors between observed HFMD case counts and the predicted number show that our predictive model gives excellent fit to the data. This implies that Baidu search queries can be used in China to track and reliably predict HFMD epidemics, and can serve as a supplement to official systems for HFMD epidemic surveillance.
Psychosocial and inflammatory factors have been associated with fatigue in breast cancer survivors. Nevertheless, the relative contribution and/or interaction of these factors with cancer-related fatigue have not been well documented.
This cross-sectional study enrolled 111 stage 0–III breast cancer patients treated with breast surgery followed by whole breast radiotherapy. Fatigue was measured by the total score of the Multidimensional Fatigue Inventory-20. Potential risk factors included inflammatory markers (plasma cytokines and their receptors and C-reactive protein; CRP), depressive symptoms (as assessed by the Inventory of Depressive Symptomatology–Self Reported), sleep (as assessed by the Pittsburgh Sleep Quality Index) and perceived stress (as assessed by the Perceived Stress Scale) as well as age, race, marital status, smoking history, menopause status, endocrine treatment, chemotherapy and cancer stage. Linear regression modeling was employed to examine risk factors of fatigue. Only risk factors with a significance level <0.10 were included in the initial regression model. A post-hoc mediation model using PROCESS SPSS was conducted to examine the association among depressive symptoms, sleep problems, stress, inflammation and fatigue.
At 1 year post-radiotherapy, depressive symptoms (p<0.0001) and inflammatory markers (CRP: p = 0.015; interleukin-1 receptor antagonist: p = 0.014; soluble tumor necrosis factor receptor-2: p = 0.009 in separate models) were independent risk factors of fatigue. Mediation analysis showed that depressive symptoms also mediated the associations of fatigue with sleep and stress.
Depressive symptoms and inflammation were independent risk factors for cancer-related fatigue at 1 year post-radiotherapy, and thus represent independent treatment targets for this debilitating symptom.
Luminous Blue Variables (LBVs) are a brief phase in the evolution of massive stars, but a very important one. The giant eruptions remain enigmatic, but the discovery of the flagship LBV η Car to be a five-year highly eccentric binary put focus on possible binarity induced mechanism for these outbursts, and prompted binarity searches among LBVs. While several wide LBV binaries were identified, HR Car is the first system found to be similar to η Car, i.e., relatively close & eccentric.
Eta Carinae is one of the most massive observable binaries. Yet determination of its orbital and physical parameters is hampered by obscuring winds. However the effects of the strong, colliding winds changes with phase due to the high orbital eccentricity. We wanted to improve measures of the orbital parameters and to determine the mechanisms that produce the relatively brief, phase-locked minimum as detected throughout the electromagnetic spectrum. We conducted intense monitoring of the He ii λ4686 line in η Carinae for 10 months in the year 2014, gathering ~300 high S/N spectra with ground- and space-based telescopes. We also used published spectra at the FOS4 SE polar region of the Homunculus, which views the minimum from a different direction. We used a model in which the He ii λ4686 emission is produced by two mechanisms: a) one linked to the intensity of the wind-wind collision which occurs along the whole orbit and is proportional to the inverse square of the separation between the companion stars; and b) the other produced by the ‘bore hole’ effect which occurs at phases across the periastron passage. The opacity (computed from 3D SPH simulations) as convolved with the emission reproduces the behavior of equivalent widths both for direct and reflected light. Our main results are: a) a demonstration that the He ii λ4686 light curve is exquisitely repeatable from cycle to cycle, contrary to previous claims for large changes; b) an accurate determination of the longitude of periastron, indicating that the secondary star is ‘behind’ the primary at periastron, a dispute extended over the past decade; c) a determination of the time of periastron passage, at ~4 days after the onset of the deep light curve minimum; and d) show that the minimum is simultaneous for observers at different lines of sight, indicating that it is not caused by an eclipse of the secondary star, but rather by the immersion of the wind-wind collision interior to the inner wind of the primary.
The role of episodic mass loss in evolved massive stars is one of the outstanding questions in stellar evolution theory. Integral field spectroscopy of nebulae around massive stars provide information on their recent mass-loss history. η Car is one of the most massive evolved stars and is surrounded by a complex circumstellar environment. We have conducted a three-dimensional morpho-kinematic analysis of η Car’s ejecta outside its famous Homunculus nebula. SHAPE modelling of VLT MUSE data establish unequivocally the spatial cohesion of the outer ejecta and the correlation of ejecta with the soft X-ray emission.
Over the past two decades a clear relation between Gamma-Ray Bursts (GRBs) and some broad-lined Type Ic Supernovae (SNe) has been observed. The use of spectropolarimetry allows us to directly probe the 3D geometry of the unresolved ejecta of SNe, which can help us better understand the physics of their explosion and the SN-GRB connection. We present 7 epochs of spectropolarimetry of the broad-lined Type Ic SN 2014ad and highlight its similarities with SN 1998bw.
We present a number of notable results from the VLT-FLAMES Tarantula Survey (VFTS), an ESO Large Program during which we obtained multi-epoch medium-resolution optical spectroscopy of a very large sample of over 800 massive stars in the 30 Doradus region of the Large Magellanic Cloud (LMC). This unprecedented data-set has enabled us to address some key questions regarding atmospheres and winds, as well as the evolution of (very) massive stars. Here we focus on O-type runaways, the width of the main sequence, and the mass-loss rates for (very) massive stars. We also provide indications for the presence of a top-heavy initial mass function (IMF) in 30 Dor.