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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.
This study examined the association between childhood conditions and arthritis among middle-aged and older adults in China. The data were derived from the 2015 wave and the life-history module of the China Health and Retirement Longitudinal Study. Face-to-face interviews were conducted with respondents age 45 and over across China. Multiple imputation was used to handle the missing data, generating a final analytic sample of 19,800. Doctor-diagnosed arthritis was the main outcome variable. Random-effects logistic regression models were used to test the proposed models. Approximately 8 per cent of the respondents had better family financial status in childhood than their neighbours. Close to 8 per cent had been hospitalised or encountered similar conditions (e.g. confined to bed or home) for at least one month in childhood. Around one-third reported better subjective health in childhood than their peers. The majority of the respondents (80%) reported that they had stable health resources, and that their mothers were illiterate during their childhood. Childhood family financial status, subjective health, mother's education, access to health care and medical catastrophic events were found to be significant factors associated with arthritis in later life, after controlling for adulthood and older-age conditions (family financial status: odds ratio (OR) = 0.885, 95 per cent confidence interval (95% CI) = 0.848–0.924; subjective health: OR = 0.924, 95% CI = 0.889–0.960; mother's education: OR = 0.863, 95% CI = 0.750–0.992; access to health care: OR = 0.729, 95% CI = 0.552–0.964; medical catastrophic events: OR = 1.266, 95% CI = 1.108–1.446). The study results highlight an important role that childhood conditions play in affecting the onset of arthritis in late life in China. Health-care providers may consider childhood conditions as a valuable screening criterion to identify risk populations, which could be used to guide health promotion and prevention programmes, and promote healthy ageing.
The present study investigated the association between dietary patterns and hypertension applying the Chinese Dietary Balance Index-07 (DBI-07).
A cross-sectional study on adult nutrition and chronic disease in Inner Mongolia. Dietary data were collected using 24 h recall over three consecutive days and weighing method. Dietary patterns were identified using principal components analysis. Generalized linear models and multivariate logistic regression models were used to examine the associations between DBI-07 and dietary patterns, and between dietary patterns and hypertension.
Inner Mongolia (n 1861).
A representative sample of adults aged ≥18 years in Inner Mongolia.
Four major dietary patterns were identified: ‘high protein’, ‘traditional northern’, ‘modern’ and ‘condiments’. Generalized linear models showed higher factor scores in the ‘high protein’ pattern were associated with lower DBI-07 (βLBS = −1·993, βHBS = −0·206, βDQD = −2·199; all P < 0·001); the opposite in the ‘condiments’ pattern (βLBS = 0·967, βHBS = 0·751, βDQD = 1·718; all P < 0·001). OR for hypertension in the highest quartile of the ‘high protein’ pattern compared with the lowest was 0·374 (95 % CI 0·244, 0·573; Ptrend < 0·001) in males. OR for hypertension in the ‘condiments’ pattern was 1·663 (95 % CI 1·113, 2·483; Ptrend < 0·001) in males, 1·788 (95 % CI 1·155, 2·766; Ptrend < 0·001) in females.
Our findings suggested a higher-quality dietary pattern evaluated by DBI-07 was related to decreased risk for hypertension, whereas a lower-quality dietary pattern was related to increased risk for hypertension in Inner Mongolia.
Suicide attempt (SA), which is one of the strongest predictors of completed suicide, is common in major depressive disorder (MDD) but its prevalence across epidemiological studies has been mixed. The aim of this comprehensive meta-analysis was to examine the pooled prevalence of SA in individuals with MDD.
A systematic literature search was conducted in PubMed, Embase, PsycINFO, Web of Science and Cochrane Library from their commencement date until 27 December 2017. Original studies containing data on prevalence of SA in individuals with MDD were analyzed.
In all, 65 studies with a total of 27 340 individuals with MDD were included. Using the random effects model, the pooled lifetime prevalence of SA was 31% [95% confidence interval (CI) 27–34%], 1-year prevalence was 8% (95% CI 3–14%) and 1-month prevalence was 24% (95% CI 15–34%). Subgroup analyses revealed that the lifetime prevalence of SA was significantly associated with the patient setting, study region and income level, while the 1-month prevalence of SA was associated with only the patient setting.
This meta-analysis confirmed that SA was common in individuals with MDD across the world. Careful screening and appropriate interventions should be implemented for SA in the MDD population.
Soil moisture is a key factor in the ecohydrological cycle in water-limited ecosystems, and it integrates the effects of climate, soil, and vegetation. The water balance and the hydrological cycle are significantly important for vegetation restoration in water-limited regions, and these dynamics are still poorly understood. In this study, the soil moisture and water balance were modelled with the stochastic soil water balance model in the Loess Plateau, China. This model was verified by monitoring soil moisture data of black locust plantations in the Yangjuangou catchment in the Loess Plateau. The influences of a rainfall regime change on soil moisture and water balance were also explored. Three meteorological stations were selected (Yulin, Yan'an, and Luochuan) along the precipitation gradient to detect the effects of rainfall spatial variability on the soil moisture and water balance. The results showed that soil moisture tended to be more frequent at low levels with decreasing precipitation, and the ratio of evapotranspiration under stress in response to rainfall also changed from 74.0% in Yulin to 52.3% in Luochuan. In addition, the effects of a temporal change in rainfall regime on soil moisture and water balance were explored at Yan'an. The soil moisture probability density function moved to high soil moisture in the wet period compared to the dry period of Yan'an, and the evapotranspiration under stress increased from 59.5% to 72% from the wet period to the dry period. The results of this study prove the applicability of the stochastic model in the Loess Plateau and reveal its potential for guiding the vegetation restoration in the next stage.
The dynamics of viscous fluid flow over a circular flexible plate are studied numerically by an immersed boundary–lattice Boltzmann method for the fluid flow and a finite-element method for the plate motion. When the plate is clamped at its centre and placed in a uniform flow, it deforms by the flow-induced forces exerted on its surface. A series of distinct deformation modes of the plate are found in terms of the azimuthal fold number from axial symmetry to multifold deformation patterns. The developing process of deformation modes is analysed and both steady and unsteady states of the fluid–structure system are identified. The drag reduction due to the plate deformation and the elastic potential energy of the flexible plate are investigated. Theoretical analysis is performed to elucidate the deformation characteristics. The results obtained in this study provide physical insight into the understanding of the mechanisms on the dynamics of the fluid–structure system.
The effect of tea intake on blood pressure (BP) is controversial. We performed a meta-analysis of randomised controlled trials to determine the changes in systolic and diastolic BP due to the intake of black and green tea. A systematic search was conducted in MEDLINE, EMBASE and the Cochrane Controlled Trials Register up to May 2014. The weighted mean difference was calculated for net changes in systolic and diastolic BP using fixed-effects or random-effects models. Previously defined subgroup analyses were performed to explore the influence of study characteristics. A total of twenty-five eligible studies with 1476 subjects were selected. The acute intake of tea had no effects on systolic and diastolic BP. However, after long-term tea intake, the pooled mean systolic and diastolic BP were lower by − 1·8 (95 % CI − 2·4, − 1·1) and − 1·4 (95 % CI − 2·2, − 0·6) mmHg, respectively. When stratified by type of tea, green tea significantly reduced systolic BP by 2·1 (95 % CI − 2·9, − 1·2) mmHg and decreased diastolic BP by 1·7 (95 % CI − 2·9, − 0·5) mmHg, and black tea showed a reduction in systolic BP of 1·4 (95 % CI − 2·4, − 0·4) mmHg and a decrease in diastolic BP of 1·1 (95 % CI − 1·9, − 0·2) mmHg. The subgroup analyses showed that the BP-lowering effect was apparent in subjects who consumed tea more than 12 weeks (systolic BP − 2·6 (95 % CI − 3·5, − 1·7) mmHg and diastolic BP − 2·2 (95 % CI − 3·0, − 1·3) mmHg, both P< 0·001). The present findings suggest that long-term ( ≥ 12 weeks) ingestion of tea could result in a significant reduction in systolic and diastolic BP.
Fluid-structure-interaction problems are ubiquitous, complicated, and not yet well understood. In this paper we investigate the interaction of a leading rigid circular cylinder and a trailing compliant filament and analyze the dynamic responses of the filament in the wake of the cylinder. It is revealed that there exist two flapping states of the filament depending on the cylinder-filament separation distance and the relevant critical distance distinguishing the two states is associated with the Reynolds number and the filament length. It is also found that the drag coefficient of the cylinder is reduced but that of the filament may be increased or decreased depending on its length. Compared with a single filament in a uniform flow, the filament of the same mechanical properties flapping in the wake of the cylinder has a lower frequency and a greater amplitude.
A study of 7,388 consecutive patients after hepatic resection between 2011 and 2012 identified hepatolithiasis, cirrhosis, and intraoperative blood transfusion as the only independent risk factors of both incisional and organ/space surgical site infection (SSI). Patients with these conditions should be cared for with caution to lower SSI rates.
A study about the achievement of dichromatic white light-emitting diodes (LEDs) was performed. A series of dual wavelength LEDs with different last quantum-well (LQW) structure were fabricated. The bottom seven blue light QWs (close to n-GaN layer) of the four samples were the same. The LQW of sample A was 3 nm, and that of sample B, C and D were 6 nm, a special high In content ultra-thin layer was inserted in the middle of the LQW of sample C and on top of that of sample D. XRD results showed In concentration fluctuation and good interface quality of the four samples. PL measurements showed dual wavelength emitting, the blue light peak position of the four samples were almost the same, sample A with a narrower LQW showed an emission wavelength much shorter than that of sample B, C, D. EL measurement was done at an injection current of 100 mA. Sample A only showed LQW emission due to holes distribution. Because of wider LQW, the emission wavelength of sample B, C and D was longer and peak intensity was weaker. Sample D with insert layer on top of LQW showed strongest yellow light emission with a blue peak. As the injection current increased, sample A showed highest output light power due to narrower LQW. Of the other three samples with wider LQW, sample D showed highest output power. Effective yellow light emission has always been an obstacle to the achievement of dichromatic white LED. Sample D with insert layer close to p-GaN can confine the hole distribution more effectively hence the recombination of holes and electrons was enhanced, the yellow light emission was improved and dichromatic white LED was achieved.
The crystal structure of a-plane GaN/ZnO heterostructures on r-plane sapphire was investigated by using the XRD and TEM measurment. It was found the formation of (220) ZnGa2O4 and crystal orientation of semipolar (10
3) GaN at GaN/ZnO interface. The epitaxial relation of normal surface direction are the sapphire (1
02) // a-GaN (11
0) and ZnGa2O4 (220) // semi-polar GaN (10
). Beside, the emission peak energy of ZnO appears shift about 60 meV in the GaN/ZnO/GaN heterostructures due to the re-crystallization of ZnO layer with Ga or N atom and the formation of the localized state.
Blue marlin are sexually dimorphic in size-at-age and other biological characteristics. However, few studies have examined the possible impact of sexual dimorphism on the population parameters and the ratios of fishing to total mortality (the exploitation ratios) for this species. We analyzed sex-specific catch-at-length data for blue marlin collected from the Taiwanese tuna longline fishery in the northwest Pacific Ocean, ranging between 100–311 cm in eye to fork length (EFL) for females and 100–236 cm EFL for males, and show that the proportion of females in the catch (the sex ratio) increases with length, with females reaching larger body sizes than males. Minor differences in fishery sex ratios among months were observed. Growth parameters, length structures, and natural mortality rates were estimated to differ between males and females, while fishing mortality rates were found to be similar. Nevertheless, the exploitation ratio for females was higher than that for males. We suggest that growth parameters and natural mortality rates should be sex-specific when assessments for sexually-dimorphic species such as blue marlin are conducted, and that management of blue marlin fisheries could be developed based on size limit regulations for large individuals.
Characteristic boundary conditions that are capable of handling general fluid mixtures flow at all flow speeds are developed. The formulation is based on fundamental thermodynamics theories incorporated into an efficient preconditioning scheme in a unified manner. Local one-dimensional inviscid (LODI) relations compatible to the preconditioning system are proposed to obtain information carried by incoming characteristic waves at boundaries accurately. The approach has been validated against a variety of sample problems at a broad range of fluid states and flow speeds. Both acoustic waves and hydrodynamic flow features can pass through the boundaries of computational domain transparently without any un-physical reflection or spurious distortion. The approach can be reliably applied to fluid flows at extensive thermodynamic states and flow speeds in numerical simulations. Moreover, the use of the boundary condition shows to improve the computational efficiency.
Shape control of nanocrystals has become an indispensable part in material research, such as developing new battery raw materials and synthesizing high activity catalysts. In this work, one-dimensional LiV3O8 nanorods have been fabricated by high temperature solid-state reaction using V2O5 nanowires as precursors obtained via a hydrothermal method. The as-prepared LiV3O8 nanorods were characterized by x-ray diffraction, transmission electron microscopy, scanning electron microscopy, and galvanostatic tests, compared with LiV3O8 samples synthesized by the traditional one-step solid-state method. The results show that LiV3O8 nanorods exhibited better electrochemical performance than those synthesized by the traditional method, indicating that a different shape will lead to huge distinctions in electrochemical properties. This work demonstrates that Li-insertion/deintercalation dynamics might be crystal morphology-sensitive.
Here we report rich and new resonant Raman spectral features for several sub-nanometer diameter single wall carbon nanotubes (sub-nm SWNTs) samples grown using chemical vapor deposition technique operating at different temperatures. We find that the high curvature in sub-nm SWNTs leads to (i) an unusual S-like dispersion of the G‑band frequency due to perturbations caused by the strong electron-phonon coupling, and (ii) an activation of diameter-selective intermediate frequency modes that are as intense as the radial breathing modes (RBMs). Furthermore, an analytical approach which includes the effects of curvature into the overlap integral and the energy gap between the van Hove singularities is discussed. Lastly, we show that the phonon spectra for sub-nm SWNTs obtained from the molecular dynamic simulations which employs a curvature-dependent force field concur with our experimental observations.
We report a low-cost and high-throughput method to fabricate large-area light emitting pattern via thermal evaporation of organic molecules on the patterned self-assembled monolayer of homogenous 3-aminopropyltrimethoxysilane. This method is based on the selective deposition of the organic light emitting molecules on the template of self-assembled monolayer (SAM), which is patterned with nanoimprinting lithography. The selectivity can be controlled by adjusting the design of the pattern, the storage duration and the substrate temperature. The deposition selectivity of the molecules may be caused by the different binding energy of the molecules with the SAM and the substrate surface.
Using high-sensitivity confocal time-resolved photoluminescence (PL) techniques, we found an ultrafast PL (40 ps-5 ns) from impurity-free surface flaws on fused silica. This PL is excited by the single-photon absorption of sub-band gap light. Regions which exhibit this PL are strongly absorptive well below the band gap, as evidenced by a propensity to damage with 3.5 eV nanosecond-scale laser pulses. Very high defect densities are needed to explain the damage thresholds observed. For such high defect densities, significant interactions between defects may strongly affect the temporal characteristics of the emission of electronic excitations. We propose that the distribution in lifetimes observed is not simply due to a large variety of defect states, but due to a variety of energy transfer interactions between defect states.
Locomotion of a passively flapping flat plate has been studied numerically by means of a multiblock lattice Boltzmann method. A flexible plate is modelled by a rigid plate with a torsion spring acting about the pivot at the leading edge of the plate. A dynamic model of this kind is called a lumped-torsional-flexibility model. When the leading edge is forced to heave sinusoidally, the plate pitches passively and propels itself in the horizontal direction as a result of the fluid–plate interaction. We have investigated various aspects of the mechanics behind the behaviour of the flapping plate, including the periodic- and non-periodic-flow states, the spontaneous motion of the plate, vortical structure and how they compare to similar propulsion systems in animals. In the periodic-flow regime, two dynamical responses of the passively pitching plate (forward and backward movements) are observed. Which movement will occur depends only on the frequency ratio F of the natural frequency of the system and the heaving frequency associated with the lumped torsional flexibility. It is found that the plate will select the forward movement when F > 1 and the backward movement when F ≤ 1. In the forward-movement regime, analysis of the dynamical behaviours and propulsive properties of the passively pitching plate indicates that the torsional flexibility can remarkably improve the propulsive performance. In addition, four kinds of vortex structures in the near wake are identified, which mainly depend on the forward speed of the plate. Finally the forward movement is compared to the flapping-based locomotion of swimming and flying animals. The results obtained in this study are consistent with the observations and measurements of swimming and flying animals; thus, they may provide physical insights into understanding of the propulsive mechanisms of the flapping wings and fins of animals.
Chinese Grouse Bonasa sewerzowi is threatened by human activity, especially during the breeding season, in the Lianhuashan Mountains, Gansu Province, north-western China. We conducted a series of simulations on the viability of this population using the computer program VORTEX. The simulations suggested that the population had an extinction probability of 17% in 100 years using data gathered from current field work. Sensitivity analysis revealed that the predicted population trend was most sensitive to chick mortality, offspring per female per year, and adult male mortality. The first two parameters are correlated with human activity such as nest loss due to egg collecting by local people. When we set initial population size to the same size as carrying capacity, 2,500 individuals would constitute a minimum viable population (MVP). This would require a forest area of about 3,780 ha, which is smaller than the size of the Lianhuashan reserve, but the current population does not constitute an MVP due to the small initial population size. Furthermore, we found that if chick mortality declined by 5% or the number of offspring produced per female increased by 5% (i.e. reducing nest loss) under the current situation, local reserve size and current population would constitute an MVP. Therefore, the most practical and simple conservation management tool would be to increase the breeding success of Chinese Grouse, especially by limiting human activity during the incubation period.