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Population ageing in China calls for evidence-based solutions, especially in terms of fulfilling long-term care needs among frail older adults. Respite services are identified as effective resources for alleviating care-giver burden and promoting the wellbeing of both older adults and their family care-givers. However, respite care is often under-used in China. This research aimed to examine factors associated with intention to use respite services among informal care-givers in Shanghai, mainland China. This study was part of the Longitudinal Study on Family Caregivers for Frail Older Adults in Shanghai. Pairs of older adults and their care-givers (N = 583) who successfully completed the 2013 and 2016 waves were included in the data analysis. Two logistic regression models were conducted, one with time-invariant and one with time-variant factors. The model with time-variant factors had greater explanatory power than the original Andersen model with time-invariant factors influencing intention to use respite services among care-givers. Care-givers had higher odds of intending to use respite services if they had higher care-giving burden, were caring elderly people who experienced care-giver transitions, or were caring for elderly people with increased function of ambulation or decreased function of feeding. The findings imply that change in functional health was a significant determinant of intention to use respite care. Relevant policy and service implications will be discussed.
Human African trypanosomiasis (HAT) is caused by Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense and caused devastating epidemics during the 20th century. Due to effective control programs implemented in the last two decades, the number of reported cases has fallen to a historically low level. Although fewer than 977 cases were reported in 2018 in endemic countries, HAT is still a public health problem in endemic regions until it is completely eliminated. In addition, almost 150 confirmed HAT cases were reported in non-endemic countries in the last three decades. The majority of non-endemic HAT cases were reported in Europe, USA and South Africa, due to historical alliances, economic links or geographic proximity to disease-endemic countries. Furthermore, with the implementation of the ‘Belt and Road’ project, sporadic imported HAT cases have been reported in China as a warning sign of tropical diseases prevention. In this paper, we explore and interpret the data on HAT incidence and find no positive correlation between the number of HAT cases from endemic and non-endemic countries. This data will provide useful information for better understanding the imported cases of HAT globally in the post-elimination phase.
We document a substantial customer complaint gap between stock and mutual financial firms. To assess whether this 21% per year complaint gap stems from complaint-prone customers in stock insurers, we examine state-adjudicated complaint success. To further delineate between customer selection or treatment explanations, we exploit within insurer complaints around random claims (natural disasters) and attention shocks (media scrutiny). Further tests reveal the complaint gap widens with greater competition, near insolvency thresholds, and with more price regulation. Overall, the results are inconsistent with the hypothesis that mutual financial firms exhibit low customer satisfaction, suggesting customers find this a beneficial organizational structure.
Social attention ability is crucial for human adaptive social behaviors and interpersonal communications, and the malfunction of which has been implicated in autism spectrum disorder (ASD), a highly genetic neurodevelopmental disorder marked by striking social deficits.
Using a classical twin design, the current study investigated the genetic contribution to individual variation in social and non-social attention abilities, and further probed their potential genetic linkage. Moreover, individual autistic traits were further measured in an independent group of non-twin participants to examine the hypothetical link between the core social attention ability and ASD.
We found reliable genetic influences on the social attentional effects induced by two distinct cues (eye gaze and walking direction), with 91% of their covariance accounted for by common genetic effects. However, no evidence of heritability or shared genetic effects was observed for the attentional effect directed by a non-social cue (i.e. arrow direction) and its correlation with the social attention ability. Remarkably, one's autistic traits could well predict his/her heritable core social attention ability extracted from the conventional social attentional effect.
These findings together suggest that human social attention ability is supported by unique genetic mechanisms that can be shared across different social, but not non-social, processing. Moreover, they also encourage the identification of ‘social attention genes’ and highlight the critical role of the core human social attention ability in seeking the endophenotypes of social cognitive disorders including ASD.
Cerebrovascular disease is the most common cause of death in China, and the incidence of ischemic stroke (240 per 100,000 people) is higher than that of hemorrhagic stroke (82 per 100,000 people). More than 80 percent of strokes can be prevented by early control of risk factors. Therefore, identifying and managing high-risk groups is a top priority in preventing stroke. The CHA2DS2-VASc score is a key prediction tool for stratifying stroke risk in individuals with atrial fibrillation (AF) as follows: zero score is low risk; one is intermediate risk; and two is high risk. The present study was undertaken to evaluate the accuracy of the CHA2DS2-VASc scoring system for stratifying ischemic stroke risk in the non-AF population.
We searched PubMed, EMBASE, and the Cochrane Library in June 2018 for relevant diagnostic studies. Study selection, data extraction, and quality assessment (using the QUADAS-2 criteria) were performed independently by two authors. Methodological variation across the selected studies precluded meta-analysis, so the results were synthesized narratively.
Seven prospective studies involving 50,652 patients (6,760 with ischemic stroke) were included. The treatment threshold ranged from two to four across the studies. Three studies reported diagnostic accuracy at a threshold of two, with a sensitivity above 0.8 and a specificity ranging from 0.32 to 0.68. The diagnostic odds ratio was greater than two (seven studies). The two studies using a treatment threshold of four reported a sensitivity of 0.59 to 0.76 and a specificity of 0.43 to 0.69. One study used a threshold of three, with a sensitivity of 0.79 and a specificity of 0.39.
The CHA2DS2-VASc score may be used to predict ischemic stroke in the non-atrial fibrillation population. Treatment thresholds greater than two provide more optimal diagnostic accuracy, although the predictive performance of the CHA2DS2-VASc score may be better in patients with chronic obstructive pulmonary disease but not AF.
We show that chief executive officers (CEOs) exhibit a hometown bias in acquisitions. Firms are over twice as likely to acquire targets located in the states of their CEOs’ childhood homes than similar targets domiciled elsewhere. Small, private home-state deals underperform other small, private deals, and the bias is stronger when acquirer governance is lax, suggesting that CEOs acquire private home-state targets for their own benefits. In contrast, large, public home-state acquisitions are value enhancing. CEOs create value in public home-state acquisitions by avoiding extremely poor deals and through deals with higher synergies. Thus, both agency issues and hometown advantages drive home-state acquisitions.
We document that a firm’s culture, specifically, its religiosity, affects its cost of debt. Firms in higher-religiosity counties have higher credit ratings and lower debt costs. The impact of religiosity is stronger for firms with greater information asymmetry and during recessions. Further, religiosity has additional explanatory power for the cost of bank loans (but not the cost of public bonds) beyond its impact through ratings. This supports the argument that banks have superior abilities in pricing soft information, such as corporate culture. Finally, the impact of religiosity is stronger when the lender is a small bank.
To assess the changes in the relationship between serum Mg and blood lipids of Chinese adults with type 2 diabetes (T2D) or central obesity, a total of 8163 subjects (mean age 59·6 years, 54·9 % men) were analysed. Participants were classified according to blood Mg (below 0·65 mmol/l, 0·65–0·95 mmol/l and above 0·95 mmol/l), T2D (yes/no) and central obesity (yes/no). Blood lipids (TAG, total cholesterol (TC), HDL-cholesterol and LDL-cholesterol) were determined by standardised methods and conditions. A significant increase in blood lipids, with the exception of HDL-cholesterol, across progressive Mg groups in all subjects was noted (P<0·05). TAG, TC, HDL-cholesterol and LDL-cholesterol were significantly higher among subjects with central obesity compared with those without central obesity (P<0·05). A significant increase in TAG, TC and LDL-cholesterol across progressive Mg groups was observed in subjects without T2D (P<0·05). However, no significant change of HDL-cholesterol and LDL-cholesterol across progressive Mg groups was observed in subjects with T2D (P>0·05). TAG, TC, HDL-cholesterol and LDL-cholesterol were significantly higher among subjects with T2D than those without T2D (P<0·05). Multivariable models for TAG and LDL-cholesterol failed to attain statistical significance in diabetics, by using a generalised linear or parsimonious model. TAG, TC, HDL-cholesterol and LDL-cholesterol were significantly higher among subjects with T2D or central obesity. Blood lipids, with the exception of HDL-cholesterol, were associated with serum Mg, but this association was somehow influenced by T2D in LDL-cholesterol. In addition, multivariable models for both TAG and LDL-cholesterol failed to attain statistical significance among subjects with T2D, different from subjects without T2D.
The Chinese government has recently expanded the scope of urban social insurance programmes. However, social protection for the labour force of the urban informal sector, which reaches about half the number of urban workers, lags significantly behind. This under-coverage may be due to institutional constraints, particularly the household registration system hukou, and self-selection behaviour related to the limited benefits of social insurance. Drawing on a recent nationwide individual-level survey and city-level statistics, this study examines these two explanations for the under-enrolment on the social insurance programme. First, results suggest that hukou and the intergovernmental fiscal system are major institutional constraints. Second, self-selection behaviour in programme enrolment is verified. Employers in the informal sector are likely to opt out of social insurance. More importantly, employers in the informal sector, with rural or non-local hukou, are likely to opt out of social insurance, which suggests that self-selection behaviour is constrained by institutions. Such findings have important implications for broad theoretical and policy debates on universal social protection.
The purpose of this work is, based on CAFE method, to study the microstructure evolution and optimize the quality of the large-scale titanium slab ingot during EBCHM. The nucleation parameters of the microstructure simulation of titanium ingot are determined based on one of the actual experimental results. For the determined parameters, our theoretical results are agreement with other experimental results. The effects of pouring temperature and pulling speed on the microstructure are presented based on CAFE method. The quantitative analyses of the simulated results show that with the pulling speed increasing, the number of grains decreases, whereas the mean grain radius increases under identical thermal condition; with the pouring temperature increasing, the mean grain radius increases under the given pulling speed. Our results are very important to obtain the optimal structure of the ingots by controlling pulling speed and pouring temperature.
With an aim to develop novel Cu–Zn alloys with high mechanical properties, in this study, Ni and Si elements were added to Cu–10Zn and Cu–20Zn alloys, and four kinds of Cu–Zn alloys were synthesized through gravity casting. The effect of the addition of Ni and Si on the microstructure and mechanical properties has been systematically investigated. Results revealed that the addition of Ni and Si not only refined the microstructure but also played significant roles to improve the mechanical properties of Cu–Zn alloys; δ-Ni2Si precipitates were formed in the Cu–20Zn–1.5Ni–0.34Si alloy, which obeyed a crystal orientation relationship of (001)Cu‖(001)δ and Cu‖δ. As compared with the Cu–20Zn alloy, the tensile strength of the studied Cu–20Zn–1.5Ni–0.34Si alloy was increased from 373.2 MPa to 776.4 MPa, and the yield strength increased from 242.1 MPa to 718.4 MPa. Operative strengthening mechanisms in the Cu–20Zn–1.5Ni–0.34Si alloy with different thermal-mechanical treatment states will be discussed in detail with the aim to draw a new strategy to develop high strength brass alloys.
The temporal dynamics of ciliate community structure in a southern Chinese shrimp aquaculture facility were investigated during the period June–September 2012. A total of 53 species belonging to 37 genera and 17 orders were recorded based on analyses of eight samples. Ciliate abundance peaked between 16 August and 14 September 2012, while the maximum number of species occurred on 26 June 2012. Clear temporal patterns were observed in the ciliate community structure. The patterns of succession of the 10 most abundant species were consistent with the results of a Canonical Analysis of Principal coordinates (CAP) analysis. Correlation analyses showed that these patterns of succession were related to temporal changes in environmental variables. In summary, the results demonstrate that the ciliate community responds predictably to environmental variations and recovers from shrimp cultivation.
The computational work and storage of numerically solving the time fractional PDEs are generally huge for the traditional direct methods since they require total memory and work, where NT and NS represent the total number of time steps and grid points in space, respectively. To overcome this difficulty, we present an efficient algorithm for the evaluation of the Caputo fractional derivative of order α∈(0,1). The algorithm is based on an efficient sum-of-exponentials (SOE) approximation for the kernel t–1–α on the interval [Δt, T] with a uniform absolute error ε. We give the theoretical analysis to show that the number of exponentials Nexp needed is of order for T≫1 or for TH1 for fixed accuracy ε. The resulting algorithm requires only storage and work when numerically solving the time fractional PDEs. Furthermore, we also give the stability and error analysis of the new scheme, and present several numerical examples to demonstrate the performance of our scheme.
A Cu–0.13Cr–0.074Ag (wt%) alloy has been synthesized by the nonvacuum melting and casting followed by thermal-mechanical treatment, and microstructure and mechanical properties have been tailored to make a trade-off between the strength and the electrical conductivity. Results illuminated that the designed alloy has a tensile strength of 473 MPa, a hardness of 140 HV, a yield strength of 446 MPa, an elongation of 10.5%, and an electrical conductivity of 94.5% IACS. Microstructure observations of the samples aged at 480 °C showed that: an fcc structure Cr-phase with a cube-on-cube orientation relationship with the Cu matrix was formed as aged for 15 min, while an ordered bcc structure Cr phase with B2 structure formed as aged for 2 h. The 3DAP results revealed that the Cr was formed to be precipitates and the Ag was formed as solutes distributing evenly in matrix. The high electrical conductivity was ascribed to the Cr element precipitated from the Cu matrix, Ag dissolved in the Cu matrix had little effect on the scattering of Cu electron.
In this paper, bymeans of a new recursive algorithm of non-tensor-product-typed divided differences, bivariate polynomial interpolation schemes are constructed over nonrectangular meshes firstly, which is converted into the study of scattered data interpolation. And the schemes are different as the number of scattered data is odd and even, respectively. Secondly, the corresponding error estimation is worked out, and an equivalence is obtained between high-order non-tensor-product-typed divided differences and high-order partial derivatives in the case of odd and even interpolating nodes, respectively. Thirdly, several numerical examples illustrate the recursive algorithms valid for the non-tensor-product-typed interpolating polynomials, and disclose that these polynomials change as the order of the interpolating nodes, although the node collection is invariant. Finally, from the aspect of computational complexity, the operation count with the bivariate polynomials presented is smaller than that with radial basis functions.
Picoeukaryotes (<2–3 μm) perform key roles for the functioning of marine ecosystems, but little is known regarding the composition and diversity of picoeukaryotes in aquaculture areas. In this study, the Illumina MiSeq platform was used for sequencing the V4 variable region within the 18S rDNA gene to analyse genetic diversity and relative abundance of picoeukaryotic communities in the Qinhuangdao scallop cultivation area of the Bohai Sea. The community was dominated by three super groups, the alveolates (54%), stramenopiles (41%) and chlorophytes (3%), and three groups, dinoflagellates (54%), pelagomonadales (40%) and prasinophytes (3%). Furthermore, a contrasting station with open water away from the eutrophic aquaculture area was chosen. The communities collected from the two stations exhibited significant differences, with higher diversity in the aquaculture area. These results provide the first snapshot of the picoeukaryotic diversity in surface waters of the Qinhuangdao scallop cultivation area, and basic data for future studies on picoeukaryote community in an aquaculture region.
The existence of black holes with masses of about one billion solar masses in quasars at redshifts z > 6 presents significant challenges to theories of the formation and growth of black holes and the black hole/galaxy co-evolution in the early Universe. Here we report a recent discovery of an ultra-luminous quasar at redshift z = 6.30, which has an observed optical and near-infrared luminosity a few times greater than those of previously known z > 6 quasars. With near-infrared spectroscopy, we obtain a black hole mass of about 12 billion solar masses, which is well consistent with the mass derived by assuming an Eddington-limited accretion. This ultra-luminous quasar with at z > 6 provides a unique laboratory to the study of the mass assembly and galaxy formation around the most massive black holes at cosmic dawn. It raises further challenges to the black hole/galaxy co-evolution in the epoch of cosmic reionization because the black hole needs to grow much faster than the host galaxy.
Phyto-oestrogens are a family of plant-derived xeno-oestrogens that appear to have beneficial effects on human health. To date, no data are available about phyto-oestrogen consumption affecting liver health in a population. The present study aimed to explore the relationship of urinary phyto-oestrogen metabolites with serum liver enzymes in US adults. A nationally representative sample of US adults in the National Health and Nutrition Examination Survey (NHANES) 2003–10 was analysed. The cross-sectional study sample consisted of 6438 adults with data on urinary phyto-oestrogen levels, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and γ-glutamyl transaminase (GGT) concentrations and data on other potential confounders. Multivariate logistic regression and linear regression were applied to assess associations between urinary phyto-oestrogen levels and ALT, AST, ALP and GGT concentrations. We found a remarkable association between urinary enterolactone and GGT in both adult males (OR 0·37, 95 % CI 0·22, 0·61; P= 0·003) and females (OR 0·37, 95 % CI 0·26, 0·54; P= 0·009). Moreover, elevated enterolactone levels were inversely associated with ALT and AST levels in adult males. However, no association was present between levels of urinary daidzein, O-desmethylangolensin, equol, enterodiol or genistein with liver enzyme levels in this population. The present study results provide epidemiological evidence that urinary enterolactone levels are associated with liver GGT levels in humans. This suggests a potential protective effect of enterolactone on human liver function. However, the underlying mechanisms still need further investigation.
Phyto-oestrogens are a family of plant-derived xeno-oestrogens that have been shown to prevent cancer in some studies. Whether phyto-oestrogen intake affects obesity status in a population is still unclear. In the present cross-sectional study, we examined the association of urinary phyto-oestrogen metabolites with obesity and metabolic parameters in children and adults. Data from 1294 children (age 6–19 years) and from 3661 adults (age ≥ 20 years) who participated in the US National Health and Nutrition Examination Survey 2001–10 were analysed. Multivariate logistic regression was applied to investigate the associations of BMI, waist circumference, serum metabolites (total cholesterol, HDL-cholesterol, LDL-cholesterol, TAG, fasting glucose and fasting insulin) and the metabolic syndrome with urinary phyto-oestrogen levels. When stratified by age and sex, we found a stronger association (OR 0·30, 95 % CI 0·17, 0·54; P< 0·001) between urinary enterolactone levels and obesity in adult males (age 20–60 years) than in children (age 12–19 years) or the elderly (age >60 years) in the same survey. However, no associations with urinary daidzein, O-desmethylangolensin, equol, enterodiol or genistein were found in the overall population. We also found that the elevation of enterolactone levels was inversely associated with TAG levels, fasting glucose levels, fasting insulin levels and the metabolic syndrome in males aged 20–60 years, but positively associated with HDL-cholesterol levels. The present results provide epidemiological evidence that urinary enterolactone is inversely associated with obesity in adult males.
To investigate the effect of pre-emptive parecoxib sodium, given in addition to routine analgesic treatment, on post-operative cognitive function in elderly patients.
Seventy elderly patients were included, who were 65–82 years of age, 48–75 kg of weight, and ASA grade I-II. Preoperative mini mental state examination (MMSE) score was ≥21 points. Patients were randomly divided into two groups: control group (group C) and parecoxib sodium group (group P). Before induction of general anesthesia, 40 mg of parecoxib sodium was injected intravenously in group P and the same volume of saline was injected in group C. Patient-controlled intravenous analgesia (PCIA) containing fentanyl and tramadol was used for post-operative pain control. A 3 ml blood sample was obtained from the peripheral vein one day before surgery, 1, 4, 24, and 72 h after surgery, and plasma cortisol, IL-6 and S100β concentrations were measured. Cognitive function was evaluated by measuring the MMSE score and a neurological test battery within 72 h after surgery. The occurrence of post-operative cognitive dysfunction (POCD), the dosage of fentanyl and tramadol used in PCIA, and the rate of additional fentanyl administration were recorded.
Compared to group C, post-operative plasma cortisol concentration decreased, the amount of fentanyl and tramadol used in PCIA was reduced, the rate of additional fentanyl administration decreased, and the rate of POCD was reduced in group P (P < 0.05).
Pre-emptive analgesia with 40 mg of parecoxib sodium can reduce the incidence of POCD in elderly patients.