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Cinnamomum chago is a woody species of the family Lauraceae endemic to Yunnan province, China, previously known from only one location, and categorized as a Plant Species with Extremely Small Population. We surveyed to determine the distribution and population size of C. chago, characterize its habitat, identify any threats, assess its conservation status, and provide guidelines for its management and conservation. During 2014–2017 we found only 64 mature C. chago, in five locations. These small, fragmented populations occur along Lancang River in Dali Prefecture at altitudes of 2,200–2,400 m. The species' extent of occurrence is c. 923 km2, with an area of occupancy of c. 60 km2. The habitat of the species has been degraded by expansion of pastoral activities and deforestation. We recommend categorization of C. chago as Endangered on the IUCN Red List, prevention of the collection of seeds and wood of the species, protection and monitoring, and ex situ propagation for future reintroductions.
The preparation of three-dimensional honeycomb nitrogen-doped carbon materials (3D-HNCMs) which can be used as electrode materials for supercapacitors is reported. The composites with the 3D honeycomb structure exhibited better electrochemical performance, and the structure and properties were proved by various means, such as SEM, TEM, IR, N2 sorption, XRD and XPS. Used as electrode materials for supercapacitors in the KOH electrolyte, 3D-HNCMs displayed a significantly high specific capacitance (409 F/g at a current of 0.5 A/g). Moreover, the 3D-HNCM electrode exhibited superior electrochemical performance, such as excellent cycling stability (98% capacitance retention after 10,000 cycles), a maximum energy density of 15.37 W h/kg, a maximum power density of 40.3 kW/kg, and low equivalent series resistance (2.1 Ω). Particularly, the electrochemical characteristic of 3D-HNCMs could be attributed to the synergistic effect of a high surface area, unique microporous and mesoporous structure, and nitrogen atom doping. These carbon materials with unique structure are promising electrode materials for future supercapacitor application.
Population-based colorectal cancer (CRC) screening programs that use a fecal immunochemical test (FIT) are often faced with a noncompliance issue and its subsequent waiting time (WT) for those FIT positives complying with confirmatory diagnosis. We aimed to identify factors associated with both of the correlated problems in the same model.
A total of 294,469 subjects, either with positive FIT test results or having a family history, collected from 2004 to 2013 were enrolled for analysis. We applied a hurdle Poisson regression model to accommodate the hurdle of compliance and also its related WT for undergoing colonoscopy while assessing factors responsible for the mixture of the two outcomes.
The effect on compliance and WT varied with contextual factors, such as geographic areas, type of screening units, and level of urbanization. The hurdle score, representing the risk score in association with noncompliance, and the WT score, reflecting the rate of taking colonoscopy, were used to classify subjects into each of three groups representing the degree of compliance and the level of health awareness.
Our model was not only successfully applied to evaluating factors associated with the compliance and the WT distribution, but also developed into a useful assessment model for stratifying the risk and predicting whether and when screenees comply with the procedure of receiving confirmatory diagnosis given contextual factors and individual characteristics.
We provide a comparative case study of rehabilitation counselling across the U.S., Japan and Taiwan focusing on the common challenges facing international constituents in the field. Through interviews with students, faculty and administrators from each of the respective countries, we use thematic coding analysis to identify key points of tension. Emergent themes comprise (a) systemic challenges, (b) student and faculty mobility, (c) cultural and linguistic differences and (d) lack of sustainable international leadership. We further discuss mitigation of these recurrent challenges and conclude collaborative research, student exchange and institutional partnerships may advance teaching, research and service scholarship of rehabilitation counselling programs, and, in turn, enhance the lives of people with chronic illness and disability worldwide.
Nutritional status of 380 hospitalised children aged from 1 month to 5 years with liver disease was evaluated in a single paediatric centre. The total prevalence of stunting (height-for-age Z (HAZ) < −2), underweight (weight-for-age Z (WAZ) < −2) and wasting (weight-for-height Z < −2) was 9·8, 9·0 and 7·9 %, respectively. The overall nutritional risk (−2 ≤ Z < −1) of stunting, underweight and wasting was 11·8, 12·9 and 12·6 %. The prevalence of undernutrition was significantly higher in children with cholestasis than children without cholestasis (stunting, 17·5 %/4·4 %, P < 0·001, and underweight, 14·9 %/4·9 %, P < 0·001). HAZ and WAZ scores were significantly higher in children without cholestasis than children with cholestasis (0·58 (sd 1·59)/−0·68 (sd 1·99), P < 0·001, and 0·37 (sd 1·35)/−0·47 (sd 1·75), P < 0·001). Further multivariate logistic regression analysis strengthened the evidence that cholestasis was significantly associated with undernutrition of stunting (OR = 4·18, P = 0·002) and underweight (OR = 3·26, P = 0·008), and suggested that the prevalence of stunting caused by infection was lower than other aetiologies in hospitalised children with liver disease (OR = 0·10, P = 0·002). We concluded that a high prevalence of malnutrition and risk of undernutrition presents in hospitalised young children with liver disease, especially in children with cholestasis. Nutrition assessment is recommended for hospitalised children with liver disease.
We evaluate the relative importance of climate change, fluvial dynamics, and anthropogenic environmental modification in forming the Holocene sedimentary record of the Luoyang Basin, a tributary drainage basin of the Yellow River, located in western Henan Province, China. Our 2011 fieldwork south of the Erlitou site in the Luoyang Basin indicates that an unconformity dating to ca. AD 1100 is roughly coincident with a major southward shift in the lower course of the Yellow River. In AD 1128, the governor of Kaifeng breached the dikes of the Yellow River to impede an advancing army, causing the Yellow River to flow south out to the Yellow Sea. We argue that the dike breach not only changed the fluvial dynamics of the Yellow River but also switched the rivers in the Luoyang Basin from an aggrading to an incising system. The resumption of sedimentation in the Luoyang Basin is roughly coincident with the next major shift of the Yellow River’s main course northward to the Bohai Sea in AD 1855. The unconformity found in the Luoyang Basin may be a legacy of historically contingent human agency rather than climatic shifts or gradual environmental modification.
Older job applicants are vulnerable to stereotype-related bias in the recruitment process. In the current study, we examined how managers’ job interview invitation decisions regarding older job applicants are influenced by applicants’ human capital-related characteristics, general economic conditions and managers’ perceptions of changes in organisational job demands. Data were collected in two waves of a vignette experiment, three years apart, among a sample of 211 Dutch managers from various organisations. Multi-level analysis showed that managers were more likely to invite older job applicants who had matching qualifications, were employed at the time of application and came with recommendations. In addition, managers’ propensity to invite older job applicants was higher in better economic conditions. The effects of recommendations were moderated by the general economic conditions and changes in organisational job demands, such that a recommendation from another employer was especially influential in bad economic conditions, while a recommendation from an internal employee was especially influential when job demands had increased. The results emphasise the importance of considering the organisational and economic context in understanding the recruitment of older workers. The findings also suggest that older workers, employers and policy makers should invest in older workers’ human capital to protect their employability.
Objective: To evaluate the measurement structure of the Taiwanese Version of the Job Satisfaction of Persons with Disabilities Scale (JSPDS). Design: A quantitative descriptive research design using exploratory factor analysis (EFA). Participants: One hundred and thirty-two gainfully employed individuals from Taiwan with poliomyelitis participated in this study. Results: EFA result indicated a three-factor structure accounting for 54.1 per cent of the total variance. The internal consistency reliability coefficients for the integrated work environment, job quality, and alienation factors were 0.91, 0.77, and 0.59, respectively. Only the integrated work environment and job quality factors showed positive correlations with life satisfaction. People with higher educational attainment also reported higher levels of job satisfaction than people with lower educational attainment. Conclusion: The three-factor measurement structure of the JSPDS appears to be parsimonious, psychologically meaningful, and interpretable, and can be used to improve the comprehensiveness of vocational rehabilitation outcome evaluation.
Previous epidemiological studies have revealed the anti-cancer effect of dietary circulating carotenoids. However, the protective role of specific individual circulating carotenoids has not been elucidated. The purpose of this study was to examine whether serum carotenoids, including α-carotene, β-carotene, β-cryptoxanthin, lycopene and lutein/zeaxanthin, could lower the risk for breast cancer among Chinese women. A total of 521 women with breast cancer and age-matched controls (5-year interval) were selected from three teaching hospitals in Guangzhou, China. Concentrations of α-carotene, β-carotene, β-cryptoxanthin, lycopene and lutein/zeaxanthin were measured using HPLC. Unconditional logistic regression models were used to calculate OR and 95 % CI using quartiles defined in the control subjects. Significant inverse associations were observed between serum α-carotene, β-carotene, lycopene, lutein/zeaxanthin and the risk for breast cancer. The multivariate OR for the highest quartile of serum concentration compared with the lowest quartile were 0·44 (95 % CI 0·30, 0·65) for α-carotene, 0·27 (95 % CI 0·18, 0·40) for β-carotene, 0·41 (95 % CI 0·28, 0·61) for lycopene and 0·26 (95 % CI 0·17, 0·38) for lutein/zeaxanthin. However, no significant association was found between serum β-cryptoxanthin and the risk for breast cancer. Stratified analysis by menopausal status and oestrogen receptor (ER)/progesterone receptor (PR) showed that serum α-carotene, β-carotene, lycopene and lutein/zeaxanthin were inversely associated with breast cancer risk among premenopausal women and among all subtypes of ER or PR status. The results suggest a protective role of α-carotene, β-carotene, lycopene and lutein/zeaxanthin, but not β-cryptoxanthin, in breast cancer risk.
To examine the vitamin D status, SNP of the vitamin D receptor gene (VDR) and the effects of vitamin D supplementation on parathyroid hormone and insulin secretion in adult males with obesity or normal weight in a subtropical Chinese city.
An intervention trial.
Shenzhen City, Guangdong Province, China.
From a cross-sectional survey conducted from June to July, eighty-two normal-weight and ninety-nine obese males (18–69 years) were screened to analyse their vitamin D status and for five SNP of VDR. From these individuals, in the same season of a different year, obese and normal-weight male volunteers (twenty-one per group) were included for an intervention trial with oral vitamin D supplementation at 1250 µg/week for 8 weeks.
For the survey, there was no significant difference (P>0·05) in baseline circulating 25-hydroxyvitamin D concentrations or in the percentages of participants in different categories of vitamin D status between the two groups. The VDR SNP, rs3782905, was significantly associated with obesity (P=0·043), but none of the examined SNP were correlated with serum 25-hydroxyvitamin D when adjusted for age, BMI and study group. After vitamin D supplementation, serum 25-hydroxyvitamin D concentration, hypersecretions of parathyroid hormone and insulin, and insulin resistance in the obese were changed beneficially (P<0·05); however, the increase in serum 25-hydroxyvitamin D was less than that of the normal-weight men.
For obese and normal-weight men of subtropical China, the summer baseline vitamin D status was similar. However, oral vitamin D supplementation revealed a decreased bioavailability of vitamin D in obese men and ameliorated their hypersecretion of parathyroid hormone and insulin resistance.
A centipede-like robot, which has high degrees of freedom (DOFs) and similar body segments, requires new real-time control to achieve diverse gaits. Therefore, we have studied the movement characteristics of multi-legged creatures and determined the features for a gait periodic relay. An instruction-relay control scheme, the three-bus control system and the required software were then designed. In our experiments with the designed control system, different gaits for the robot could be achieved, and the phase difference between body segments could be changed by altering the delay time. As a whole, this control system could accomplish the required control task and reasonably simplify the gait control algorithms and procedures.
Single-walled carbon nanotubes (SWCNTs), which have a unique electronic structure, nanoscale diameter, high curvature, and extra-large surface area, are ideal for making a new class of nanocomposites. In this study, under the condensed phase optimized molecular potentials for atomistic simulation studies force field, classical molecular dynamics simulation is used to study the molecular interactions between SWCNTs and the molecules of binaphthyl core-based chiral phenylene dendrimers (G0–G2). The simulation results revealed that both G2 and G1 molecules have obvious attractive interactions with SWCNTs, and theoretically demonstrated the possibility of noncovalent functionalization of SWCNTs with chiral dendrimers. The influence of temperature on composites was also studied, and the results indicate that the interaction decreases strongly for SWCNTs@G1 and SWCNTs@G2 with increasing temperature. The possibility during real-world composite processing would create the desired structure bridges between nanotubes and chiral dendrimers, which can be used to produce nanocomposites such as highly sensitive as well as enantioselective fluorescent sensors.
Flow separation results in many problems to single expansion ramp nozzle (SERN) and hypersonic vehicle. However, little research has been conducted on the separation patterns and their effects on SERN’s performance. In the present paper, the numerical simulation is adopted to get the intuitive results and help to analyse the separation phenomena in SERN thoroughly. The main separation pattern is the restricted shock separation (RSS) in SERN, and the free shock separation (FSS) only appears in a small range of the nozzle pressure ratio (NPR), which is much different from the axisymmetric rocket nozzle. Further CFD results show that the separation pattern transition makes great effects on the performance of SERN, especially the lift. Moreover, the performance of SERN has an extreme in the separation pattern transition because of the main jet impinging on the expansion ramp. The transitions occur in both the startup and shutdown processes but the critical nozzle pressure ratios of the separation pattern transitions are different, which leads to a hysteresis loop of SERN performance.
The protective effect of dietary carotenoid intake on the risk of breast cancer is inconclusive. Moreover, data on dietary carotenoids in relation to breast cancer in non-Western populations are scarce. The aim of the present study was to examine the association between dietary carotenoid intake and the risk of breast cancer among Chinese women. A total of 561 cases and 561 controls who were frequency matched by age (5-year interval) and residence were recruited in the present case–control study. Dietary intake information was collected by a face-to-face interview using a validated FFQ. The OR and 95 % CI were assessed by multivariate logistic regression after adjusting for various potential confounders. An inverse association was observed between the consumption of α-carotene, β-carotene, β-cryptoxanthin and lutein/zeaxanthin and the risk of breast cancer. The multivariate-adjusted OR for the highest quartile of intake compared with the lowest quartile of intake were 0·61 (95 % CI 0·43, 0·88) for α-carotene, 0·54 (95 % CI 0·38, 0·78) for β-carotene, 0·38 (95 % CI 0·26, 0·52) for β-cryptoxanthin and 0·49 (95 % CI 0·34, 0·71) for lutein/zeaxanthin. Lycopene intake was not found to be associated with the risk of breast cancer, with the adjusted OR of 0·89 (95 % CI 0·61, 1·30). These inverse associations were more evident among pre-menopausal women and women who were exposed to second-hand smoke. The protective effect of specific carotenoid intake was observed for all subtypes of hormone receptor status of breast cancer. The present study indicated that a greater intake of specific carotenoids was associated with a decreased risk of breast cancer among Chinese women residing in Guangdong.
Vertically aligned graphene was grown by plasma-enhanced chemical vapor deposition using methane feedstock. Optical emission spectroscopy (OES) was used to monitor the plasma species, and Raman spectroscopy was used for characterizing the properties of as-grown vertically aligned graphene. OES-derived information on plasma species, such as C, C2, CH, and H, are correlated with the properties of the vertically aligned graphene. Graphene grown at 250 W and 15 sccm exhibited the lowest amount of defects. Although OES peak intensities occurred at the highest power and lowest flow conditions, the OES peak ratios of plasma species had a greater dependence on flow rate and exhibited a saddle point in the atomic C/H ratio corresponding to optimal growth involving the lowest amount of overall defects. Plasma diagnostics provides a valuable approach to optimize growth characteristics and material properties.
Ethical leadership has been widely identified as the key variable in enhancing team-level organizational citizenship behavior (team-level OCB) in western economic and business contexts. This is challenged by empirical evidence in China and findings of this study. Our study examined the relationship between ethical leadership, organizational ethical context (ethical culture and corporate ethical values) and team-level OCB. Team-level data has been collected from 57 functional teams in 57 firms operating in China. The findings suggest that although ethical leadership is positively associated with team-level OCB, ethical context positively moderates the relationship between ethical leadership and team-level OCB. The higher ethical context is found to be, the greater is the (positive) effects of ethical leadership on team-level OCB and the opposite holds true when ethical context is low. Key implications are discussed on the role of contextual ethics for team-level OCB, while managerial implications include how non-Chinese firms could improve team-level OCB in the Chinese business context.
We have investigated the stability of short channel (1.5μm) p-Type polycrystalline silicon (poly-Si) Thin Film Transistors (TFTs) on the glass substrate under AC bias stress. The variation of threshold voltage in short channel poly-Si TFT was considerably higher than that of long channel poly-Si TFT. Threshold voltage of the short channel TFT was considerably moved to the positive direction during AC bias stress, whereas the threshold voltage of a long channel was rarely moved. The variation of threshold voltage in the short channel p-type TFT under AC bias stess was more compared to that under DC bias stress. The threshold voltage of short channel (L=1.5μm) poly-Si TFT was increased about -7.44V from -0.305V to -7.745V when VGS = 5 (base value) ~ -15V (peak value), VDS = -15V was applied for 3,000 seconds. This positive shift of threshold voltage and significantly degraded s-swing value in the short channel TFT under dynamic stress (AC) may be due to the increase of the stress-induced trap state density at gate insulator / channel interface region.
Nanostructured silicon nitride solids (NANO–SSNS) were investigated by x–ray photoelectron spectroscopy (XPS), electron spin resonance (ESR) and dielectric measurements. It is found that the dielectric constant of NANO–SSNS depends strongly on the measuring frequency, f. When f<100Hz, at room temperature it is forty times as much as that of conventional Si3N4. ESR measurements show that a large number of unbinding electrons exist in interfaces. This suggests that the NANO–SSNS possess strong polarity. The study on the bond properties indicates that a large number of unsaturated and dangling bonds exist in interfaces of NANO–SSNS.