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In this paper, a wireless bipolar drive has been proposed and implemented for AC application, which not only performs selective wireless power transfer (WPT), but also secondary-converterless operation for frequency-controllable AC output. The key is to use the proposed self-drive circuit based on the selective WPT with two different resonant frequencies. Besides, the inductor-capacitor-inductor (LCL) compensation network is newly adopted to achieve power equalization so that only one transmitter is needed to serve two receivers and control the low-frequency AC output. As a result, there is no additional battery, controller, and converter at the secondary side and hence the system robustness can be significantly improved. Finally, experimental results are offered to verify the proposed topology.

OBJECTIVE In this study, a genetic risk score (GRS) for the body mass index (BMI) tested and built using a large sample of Chinese individuals aged at least 50 years in southern China. We collected information regarding the participants' weights at 20 years of age and middle age and tested the BMI-GRS effect modes. METHODS This study involved a prospective study design. The genetic data of the participants in from the Guangzhou Biobank Cohort Study and selected BMI-related single-nucleotide polymorphisms (SNPs) were used to establish the GRS. RESULTS We included 13 597 participants with 12 SNPs. After adjusting for covariates, the high-GRS group was 36% (95% CI: 25%-48%) and 34% (95% CI: 23%-47%) more likely of being overweight at baseline and follow-up, respectively, and 56% (95% CI: 34%-82%) and 49% (95% CI: 29%-72%) more likely of being obese at baseline and follow-up, respectively, compared with the low-GRS group (P-value for all trends

Improvement in fertilization methods, including the optimal matching of nutrient supply and root nutrient absorption by applying nitrogen (N) in the root zone of crop, is necessary to improve N use efficiency (NUE), maintain high stable yield cultivation of maize, and contribute toward future environmental protection. The current practice of split surface broadcasting (SSB) of N is labor-intensive and the surface broadcasting causes a large amount of N to leach into the environment, yet it does not substantially increase maize yield. Root zone fertilization (RZF) has been identified as an efficient way to solve such problems. However, information on the appropriate amount of N fertilizer under RZF for summer maize remains limited. Therefore, in this study, a two-year consecutive field experiment was conducted during 2015&ndash, 2016 in Anhui province, China, to investigate the effect of N rate and application method on grain yield, nutrient uptake, and NUE of summer maize. The method chosen is not only important to increase grain yield but also critical for reducing N rate and potential loss in the maize cropping system. The experiment comprised six N rates (90, 135, 180, 225, 270, and 360 kg N hm&minus, 2) and two N application methods in both 2015 and 2016. The two N application methods included SSB and one-time RZF. Results showed that grain yield of summer maize increased first and then decreased with the increase of N rate, however, when the N rate increased to 270 kg hm&minus, 2, the grain yield increased slowly or even decreased. Compared with SSB, RZF increased grain yield by 4%, and the effect of N on grain yield was mainly related to the number of kernels per ear and 1000-seed weight. One-time RZF increased N apparent recovery efficiency by 18% (7.2 percentage points) compared with SSB and also improved the N agronomic efficiency, N physiological efficiency, and N partial factor productivity. In the comprehensive consideration of yield target, NUE, and soil N balance, the optimal N rate for summer maize in the vertisol soil of Anhui province was 180&ndash, 225 kg hm&minus, 2 for one-time RZF, which reduced N fertilizer by 14% compared with the SSB. Overall, one-time RZF has great potential for green and sustainable agriculture, and thus fertilization machines are worthy of development and application in maize cropping systems.

This paper proposes and implements a novel class of inductor-capacitor-capacitor wireless coordinative DC motor drives, which not only performs selective wireless power to motors, but also achieves power equalization to ensure the same operation for isolated robotic arms. The key is to make use of the selective wireless power transfer with several resonant frequencies and then use only one transmitter with the inductor-capacitor-capacitor compensation network to provide multiple-frequency transmission without relying on the switched-capacitor array. In order to provide simultaneous and independent wireless power to different motors and hence achieve the desired coordinative motion, a time-division multiplexing scheme and burst firing control are newly employed. Thus, the wireless power transfer system with multiple receivers can achieve better flexibility and simplicity. Both finite element analysis and experimental results are given to verify the validity of the proposed inductor-capacitor-capacitor wireless coordinative DC motor drive. As a result, the motors can achieve independent motion with 1200 rpm and simultaneous motion with 400 rpm when the torque is 10 Ncm, and the operating frequencies are set at 110 kHz and 130 kHz. Published version

Selenium (Se) accumulation in plant foods may be providing dietary Se to minimize the health problems related to Se deficiency. In this study, rice plants were cultivated in different naturally seleniferous soils (0.5&ndash, 1.5 mg Se kg&minus, 1). Se concentration in rice plant tissues was analysed, and the distribution and translocation of Se in rice were also studied. The effect of exogenous Se on yield and Se concentration in rice grain was also investigated by spraying Na2SeO3 (15 mg L&minus, 1, 15 g ha&minus, 1). Results show that Se concentration in root, straw and grain of rice was increased with increased concentrations of Se in seleniferous soils. The root accumulated higher Se than straw and grain under the same naturally seleniferous soil. Spraying Se significantly increased Se concentration in grain, hull, brown rice and polished rice compared with spraying water. Se concentration in the grain fractions was in the following order: Bran &gt, brown rice &gt, whole grain &gt, polished rice &gt, hull. About 13.7% Se in wholegrain was discarded by milling process if about 6.9% of it was polished as bran. Se-enriched rice could be produced in naturally seleniferous soils with Se concentration from 0.5 to 1.0 mg kg&minus, 1, and this polished rice would provide enough Se (60&ndash, 80 &mu, g day&minus, 1) to satisfy the human requirement. Therefore, naturally seleniferous soils may be an effective way to produce Se-enriched rice without spraying Se fertilizer, which will be more economically feasible and environmentally friendly for without exogenous Se added to the soils or plants. However, the polished rice and brown rice, produced by spraying Na2SeO3 (15 g ha&minus, 1) or grown in soil with total Se upto 1.5 mg kg&minus, 1 was not suitable for daily human consumption, unless diluted with Se-deficient rice to meet the standard (&le, 0.3 mg Se kg&minus, 1). This study imparted a better understanding of the utilization of seleniferous soils and Se-enriched rice for human health and food safety.

In this paper, a novel wireless servo motor drive is proposed and implemented, which artfully integrates wireless power transfer into the dc servo motor drive to achieve wireless bidirectional servo motion. Prominently, there is no power converter or controller at the servo motor side to realize the bidirectional rotation, while the motor control is fully conducted at the transmitter side. The key is to adopt only one transmitter with LCL network to achieve power equalization of two receiver coils, hence realizing bidirectional motion. Meanwhile, the phase-shift control method is newly developed to perform the desired speed control at the transmitter side, without requiring any switched capacitor arrays. As a result, the proposed wireless bidirectional servo motor drive takes the definite advantages of electrocution free and totally sealable. Both calculation and experimental results are presented to validate the feasibility and controllability. For the prototype, the transmission distance can reach up to 130 mm and the transmission efficiency can be up to 85%. Accepted version This work was supported by Hong Kong Research Grants Council, Hong Kong Special Administrative Region, China, under Grant 17204317.

Objective To study whether abnormal spirometric patterns were associated with differential mortality in Chinese adults with and without dyspnea. Methods Guangzhou Biobank Cohort Study (GBCS) participants were classified by spirometric patterns and presence of dyspnea into 6 groups: normal spirometry (NS), restriction on spirometry (ROS) and airflow obstruction (AO), each with and without dyspnea. Adjusted hazard ratios (aHRs) were calculated for mortality using Cox models. Results Among 16777 subjects, 1595 (9.5%) had ROS, 1036 (6.2%) had AO and 1009 (6.0%) had dyspnea. A total of 1993 deaths (11.9%) occurred during 11-year follow-up. Using NS without dyspnea as reference, NS with dyspnea was significantly associated with increased cardiovascular mortality risk (aHRs 1.61 (95% confidence interval (CI) 1.18–2.19); ROS with and without dyspnea were associated with increased risks of all-cause (aHRs 1.46 (95% CI 1.28–1.66) and 1.81 (95% CI 1.33–2.47)) and cardiovascular mortality (aHRs 1.89 (95% CI 1.55–2.31) and 1.85 (95% CI 1.12–3.03)), but not of lung cancer mortality (aHRs 1.33 (95% CI 0.91–1.94) and 1.35 (95% CI 0.49–3.70)); AO with and without dyspnea were associated with increased risks of all-cause (aHRs 1.59 (95% CI 1.36–1.86) and 2.36 (95% CI 1.77–3.15)), cardiovascular (aHRs 1.43 (95% CI 1.08–1.90) and 1.61 (95% CI 0.91–2.82)) and lung cancer mortality (aHRs 1.91 (95% CI 1.29–2.84) and 3.01 (95% CI 1.46–6.23)). These associations did not vary by sex or smoking status (all P-values for interaction >0.05). Conclusion Both ROS and AO, with and without dyspnea, were associated with increased all-cause and cardiovascular disease mortality. The increased risk of all-cause was greater and that of cardiovascular mortality was lower for AO than ROS. AO showed significantly increased risk of lung cancer but ROS did not. (272 words).

Objective To examine the changes in body mass index (BMI) and waist circumference (WC) in Guangzhou, South China, which is probably experiencing the most rapid economic transition in history. Methods In this study, 17,786 Chinese aged 50+ years were recruited from 2003 to 2008 and followed up until 2012. BMI and WC were measured at two time points. Results During the mean follow-up of 3.6 years (median = 3, interquartile = 1), age-adjusted mean BMI increased only slightly. By contrast, mean WC increased sharply by 0.94 cm (95% confidence interval 0.93-0.94) annually in men and 1.29 cm (1.28-1.29) annually in women. In 77% of women and 69% of men, WC increased, and among them, the mean annual increase was 2.01 cm and 1.70 cm, respectively. Among healthy, never-smoking participants, the incidence of central obesity was 29.0% (36.4% in women and 14.2% in men). The incidence of general obesity was 1.9% and was similarly low in both men and women (2.1% vs. 1.8%). Conversely, 20.3% of individuals with general obesity became nonobese, and 12.8% of individuals with central obesity returned to normal. Conclusions Central obesity has risen sharply in this cohort. Such increases may have been greatly underestimated previously and should form the basis of an even stronger warning for regions undergoing economic transitions in China and elsewhere.

BACKGROUND: Serum antibody to influenza can be used to identify past exposure and measure current immune status. The two most common methods for measuring this are the hemagglutination inhibition assay (HI) and the viral neutralization assay (NT), which have not been systematically compared for a large number of influenza viruses. METHODS: 151 study participants from near Guangzhou, China were enrolled in 2009 and provided serum. HI and NT assays were performed for 12 historic and recently circulating strains of seasonal influenza A. We compared titers using Spearman correlation and fit models to predict NT using HI results. RESULTS: We observed high positive mean correlation between HI and NT assays (Spearman's rank correlation, rho=0.86) across all strains. Correlation was highest within subtypes and within close proximity in time. Overall, an HI=20 corresponded to NT=10, and HI=40 corresponded to NT=20. Linear regression of log(NT) on log(HI) was statistically significant, with age modifying this relationship. Strain-specific area under a curve (AUC) indicated good accuracy (>80%) for predicting NT with HI. CONCLUSIONS: While we found high overall correspondence of titers between NT and HI assays for seasonal influenza A, no exact equivalence between assays could be determined. This was further complicated by correspondence between titers changing with age. These findings support generalized comparison of results between assays and give further support for use of the hemagglutination inhibition assay over the more resource intensive viral neutralization assay for seasonal influenza A, though attention should be given to the effect of age on these assays. This article is protected by copyright. All rights reserved.

Objective The role of estrogen in cognitive function and depressive symptoms is controversial due to discrepancies between results from randomized controlled trials (RCT) and observational studies. Mendelian randomization analysis may provide further insights concerning the role of estrogen in these outcomes as it assesses the effect of lifelong endogenous exposure but is less vulnerable to confounding than observational studies. Method We used separate sample instrumental variable analysis to estimate the association of log 17β estradiol with cognitive function (Delayed 10 word recall, and Mini Mental State Examination (MMSE)) and depressive symptoms (Geriatric Depression Scale (GDS)) in older Chinese women of the Guangzhou Biobank Cohort Study (GBCS, n = 3086). The estimate was derived based on the Wald estimator, the ratio of the association of genetic determinants (rs1008805 and rs2175898) of log 17β-estradiol with cognitive function and depressive symptoms in GBCS and the association of log 17β-estradiol with genetic determinants in the sample of young women in Hong Kong (n = 236). Results Genetically predicted 17β-estradiol was not associated with delayed 10-word recall (0.42 words per log increase in 17β-estradiol (pmol/L), 95% confidence interval (CI) − 0.49 to 1.34) MMSE (0.39 per log increase in 17β-estradiol (pmol/L), 95% CI − 0.87 to 1.65) or GDS (0.24 per log increase in 17β-estradiol (pmol/L), 95% CI − 0.57 to 1.05). Conclusion These results were largely consistent with evidence from RCTs and did not show any beneficial effect of estrogen on cognitive function and depressive symptoms. However, larger Mendelian randomization analyses are needed to identify any minor effects.

Purpose The role of estrogen in cardiovascular health remains contested with discrepancies between findings from randomized controlled trials and observational studies. Mendelian randomization, which assesses the effect of lifelong endogenous exposure, may help elucidate these discrepancies. Methods We used separate sample instrumental variable analysis to estimate the association of log 17β-estradiol with factors related to cardiovascular disease risk (systolic and diastolic blood pressure, lipids, fasting glucose, body mass index, waist hip ratio, and waist circumference) and Framingham score, a predictor of 10-year risk of ischemic heart disease events, in older Chinese women from the Guangzhou Biobank Cohort Study (GBCS, n = 3092). The estimate was derived using the Wald estimator, that is, the ratio of the association of genetic determinants (rs1008805 and rs2175898) of log 17β-estradiol with cardiovascular disease risk factors and Framingham score in GBCS and the association of these genetic determinants with log 17β-estradiol in a sample of young women from Hong Kong (n = 236). Results Genetically, higher 17β-estradiol was not associated with any cardiovascular disease-related risk factor or with Framingham score (−0.01, 95% confidence interval = −1.34 to 1.31). Conclusions Lifetime exposure to estrogen does not appear to be cardioprotective via the cardiovascular disease-related risk factors examined.

Cigarette smoking is associated with thicker carotid intima-media thickness (IMT), probably partly through inflammatory pathways. However, to what extent does inflammation mediate the smoking-carotid atherosclerosis association is unclear. We investigated the mediating effect of inflammation on the association between cigarette smoking and carotid IMT, and quantified the respective contributions of inflammatory markers to this association.A total of 1752 participants from Guangzhou Biobank Cohort Study-Cardiovascular Disease Sub-cohort (GBCS-CVD) were included. Using causal mediation analysis under the counterfactual framework, we decomposed total effects of cigarette smoking on IMT into indirect effects (through inflammatory response) and direct effects (not through inflammatory response).After adjusting for traditional risk factors, the indirect effects of per 10/L increment in leukocyte and granulocyte, per mg/L increment in high-sensitivity C-reactive protein (hs-CRP), and per mg/dL increment in fibrinogen on carotid IMT was 0.0028 mm (95% confidence interval [CI], 0.0011-0.0047), 0.0019 mm (95% CI, 0.0006-0.0034), 0.0017 mm (95% CI, 0.0006-0.003), and 0.001 mm (95% CI, 0.0001-0.0021), respectively. No evidence for a mediating role of lymphocyte was found. The proportion of the smoking-IMT association mediated by leukocyte, granulocyte, hs-CRP, and fibrinogen was 12.57% (95% CI, 8.50%-22.11%), 8.50% (95% CI, 5.76%-15.09%), 7.64% (95% CI, 5.20%-13.79%), and 4.48% (95% CI, 3.04%-8.03%), respectively. Restricting data analysis to men showed similar results.The effects of cigarette smoking on IMT were partly mediated by leukocyte, hs-CRP, and fibrinogen. The mediating role of leukocyte was likely mainly driven by higher granulocyte.

Soft magnetic composites (SMCs) based magnetic cores are attractive in high-frequency inductor design. The desired overall core permeability of SMC core can be achieved by adjusting the powder size, addition of insulation material and phosphoric acid, and pressure during the preparation process to reduce the air gap loss and ease the inductor design. The nanocrystalline alloy (Fe-Cu–Nb–Si–B) is an emerging SMC with high saturation flux density and low hysteresis loss, showing potential suitability for SMC-based magnetic cores. To date, nanocrystalline alloys are mostly used in form of laminated ribbon for magnetic cores, and nanocrystalline powder SMCs have been seldom used in practice. Also, neither experimental validation nor comparison with other commercialized and commonly used SMC cores has been reported. In this article, the structure and manufacturing process of nanocrystalline powder cores are introduced. The calculation of core loss is defined for the nanocrystalline powder core. The characteristics and performance of the nanocrystalline powder toroidal core are compared with those of existing commercial SMC cores, such as Fe–Si powder (X flux), Fe–Ni powder (High flux), Fe–Si–Al powder (Kool Mμ), and Fe-Ni–Mo powder (MPP). Experimental results are conducted at frequencies from 100 to 600 kHz to verify the loss calculation and feasibility of this new nanocrystalline powder core.

Background evidence concerning the relationship between sleep quality and cognitive impairment is limited and inconsistent. Objective to examine the association of sleep quality with memory impairment and poor cognitive function in a large sample of older Chinese. Methods 15,246 participants aged 50+ years of the Guangzhou Biobank Cohort Study who attended the second physical examination from 2008 to 2012 were included. Sleep quality was assessed using Pittsburgh Sleep Quality Index (PSQI), and cognitive performance was assessed using both Delayed Word Recall Test (DWRT) and Mini-Mental State Examination (MMSE). Memory impairment was defined by DWRT score Results after adjusting for potential confounders, lower habitual sleep efficiency was associated with a higher risk of memory impairment and poor cognitive function with a dose-response pattern (both P for trend Conclusions in older Chinese people, lower habitual sleep efficiency was associated with a higher risk of memory impairment and poorer cognitive function.

It is urgently to minimize nitrogen (N) loss while simultaneously ensuring high yield for maize in China. A two-year field experiment was conducted to determine the effects of root-zone fertilization (RZF) and split-surface broadcasting (SSB) on grain yield, N use efficiency (NUE), and urea-15N fate under different N rates (135, 180 and 225 kg ha−1). Results showed that RZF increased grain yield by 11.5%, and the N derived from fertilizer (Ndff%) by 13.1–19.6%, compared with SSB. The percentage of residual 15N in the 0–80 cm soil was 37.2–47.4% after harvest; most 15N (64.4–67.4%) was retained in the top 20 cm. RZF significantly increased the N apparent recovery efficiency (NARE) and 15N recovery in maize by 14.3–37.8% and 21.9–30.0%, respectively; while decreased N losses by 11.2–24.2%, compared with SSB. The RZF of urea can be considered a slow-release fertilizer, which better matches maize N demand and effectively reduces N losses. Overall, RZF achieved yields as high as the SSB, but with a 20–25% reduction in N application. These results help improve our understanding of N fate in the maize cropping system, and may help guide recommendations for N management in southeastern China.

In this paper, the heating performance of the pan-shaped and wok-shaped utensils on a same planar induction cooktop is analyzed and compared. Generally, the domestic induction cooker has a planar cooktop and adaptively heats pan-shaped utensils based on the magnetic induction mechanism. However, the shape of utensils are different in different cooking methods or cultures, specifically, the wok-shaped utensils are extremely popular in Asian countries. Therefore, the heating performance of the pan-shaped and wok-shaped utensils on a same planar induction cooktop should be considered and analyzed. This paper compares the thermal effect of the aforementioned utensils under the same planar cooktop theoretically and numerically. Abundant simulation results such as the magnetic flux density, eddy current distribution, Joule loss density and temperatures are given to validate the theoretical calculation. Finally, a possible solution is proposed to conquer the problem.

Due to cleanliness, convenience and high efficiency, wireless power transfer (WPT) technology has been extensively and deeply investigated. In recent years, energy encryption has drawn researchers’ attention to satisfy practical requirements of security and reliability in the theme of intelligent transportation and smart city. Especially for roadway-charging electric vehicles (EVs), the use of energy encryption can guarantee the transmitted energy being effectively harvested by the authorized receptors instead of being secretly stolen by the unauthorized ones. Recently, a chaotic encryption strategy based on switched capacitor arrays has been proposed to realize energy security in WPT systems [1, 2]. However, because of the need of discretely adjusting the resonant capacitance and hence the operating frequency, this encryption scheme suffers from the drawbacks of limited energy-transferred channels, high voltage stress across switches and relatively low flexibility. In addition, a generic encryption model based on certificate-less cryptography has been developed to improve the energy security performance for WPT systems [3], but its computational complexity and time involved seriously restrain from dynamically encrypting the operating frequency. Meanwhile, a traditional series-to-series (SS) topology with fixed values of resonant inductance and capacitance has been identified to exhibit a selective characteristic for multiple loads when operating at the selected receptor’s resonant frequency [4]. This mechanism can be newly extended to derive an energy-encrypted transmitter without using a switched-capacitor array for multiple energy receptors such as roadway-charging EVs. Consequently, in this paper, a switched-capacitorless energy-encrypted transmitter is proposed for roadway-charging EVs. Moreover, a two-dimension chaotic frequency-and-duration encryption (FDE) algorithm is proposed to improve the security performance while maintaining relatively high efficiency.

Background Findings describing the relationship between pulmonary function and peripheral vascular function have been inconclusive. We explored this relationship in Guangzhou Biobank Cohort Study-Cardiovascular Subcohort (GBCS-CVD). Methods Brachial-ankle pulse wave velocity (baPWV) and ankle brachial index (ABI) were measured by a waveform analyser, and pulmonary function by turbine flowmeter spirometry. Predicted forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were derived using equations for Chinese. Regression analyses were used to investigate the association. Results Of 1528 older Chinese, 980 (64.1%) had arterial stiffness (baPWV ≥1400 cm/s), but only 29 (1.9%) had peripheral arterial disease (PAD) (ABI

Background and challenges to implementation Many smoking cessation clinics are passive and dependent on motivated smokers to proactively seek help. Also, smoking cessation clinics are not well publicized. Most healthcare professionals are unaware of the existing smoking cessation services, and rarely refer smokers to these clinics. Many smokers who want to quit do not proactively visit these clinics or call the quitline. Most if not all these clinics and services are not receiving the expected number of smokers and some are dormant or closed down quietly. Intervention or response This project, commissioned by the Hong Kong Tobacco Control Office, was to develop and publish an evaluation tool (E-tool, version 1.1) for smoking cessation clinics and services. The project team gathered documentations and data from smoking cessation clinics in Hong Kong, Guangzhou and Beijing. Stakeholders discussed and agreed on what would be the most appropriate items for the E-tool. The E-tool draft was pilot-tested by 27 smoking cessation clinics and hospitals in Hong Kong, China Mainland and Southeast Asian countries (from the WHO Fellowship Programme on Tobacco Control, organized by Hong Kong Tobacco Control Office). Results and lessons learnt The finalized E-tool (version 1.1) consists of 33 most basic and essential items in 4 assessment components: Organization assessment (17 points), Environmental assessment (14 points), Process assessment (28 points) and Outcome assessment (11 points). The E-tool and user manual have English, traditional Chinese and simplified Chinese versions. All materials can be freely accessed in https://mrct.sph.hku.hk/web/. Conclusions and key recommendations The E-tool for smoking cessation clinics and services can be used to evaluate the quality and outcomes of existing clinics and services, and provide an outcome-oriented guidance for setting up new clinics and services. We invite all kinds of smoking cessation clinics and services in any territories to use this E-tool, and to provide feedback for the development of more advanced E-tools in the future.

Objective: To study whether spirometry respiratory disorders with and without dyspnea were associated with mortality in older Chinese. Methods: Guangzhou Biobank Cohort Study participants were classified by respiratory patterns and presence of dyspnea into 6 groups: normal spirometry (NS), airflow obstruction (AO) and restrictive respiratory pattern (RRP) with and without dyspnea (dyspnea defined by British modified Medical Research Council scale ≥2). Adjusted hazard ratios (aHRs) were calculated using Cox models. Results: In all 16377 subjects, the increased mortality risk from AO was greater for all-cause (aHR 1.72 (95% confidence interval (CI) 1.49-2.00) vs. 1.46 (95% 1.29-1.65)) but lower for cardiovascular diseases (aHR 1.47 (95% CI 1.12-1.92) vs. 1.77 (95% CI 1.46-2.14)) than from RRP. Only AO was associated with lung cancer mortality (aHR 2.22 (95% CI 1.53-3.24)) (all P values 0.27), all the other aHRs were similar in those with and without dyspnea (aHRs ranged from 1.43 to 3.99, P values

Objective The objective of this study was to examine the role of stress across the life course in the development of depression among older adults in a non-Western developing setting. Methods Multivariable linear and multinomial logistic regression were used in cross-sectional analyses of 9729 Chinese participants (mean age 60.2 years) from phase 3 of the Guangzhou Biobank Cohort Study (2006–2008) to investigate the association of childhood adversities and adulthood stressors with depression. Results Childhood adversities were associated with mild depression (odds ratio (OR) 1.78, 95% confidence interval (CI) 1.58, 2.02) and moderate-to-severe depression (OR 2.30, 95% CI 1.68, 3.15), adjusted for age, sex, education and childhood socio-economic status. Past-year adulthood stressors were also associated with mild depression (OR 1.96, 95% CI 1.54, 2.02) and moderate-to-severe depression (OR 3.55, 95% CI 2.21, 5.68), adjusting additionally for occupation and income. Adulthood stressors were more strongly associated with depressive symptoms among individuals with a history of childhood adversities. Conclusions Childhood adversities and adulthood stressors were independently associated with an increased risk of depression among older ambulatory adults, although adulthood stressors were more strongly associated with depression following exposure to childhood adversities. This is consistent with evidence from Western settings in which the social context of risk and protective factors for depression may differ and implies that the role of stress in the aetiology of depression is not context specific. Copyright © 2015 John Wiley & Sons, Ltd.

Western observational studies show that moderate alcohol use is associated with lower cardiovascular disease (CVD) risk, but these associations may be confounded by the healthier attributes of moderate users in these settings. Mendelian randomization analysis may help to ascertain the causal effect of moderate alcohol use on specific factors related to CVD and thereby clarify the role of alcohol. We used Mendelian randomization analysis with the aldehyde dehydrogenase 2 gene (ALDH2) as an instrumental variable to examine the association of alcohol units (10 g of ethanol) per day with heart rate-corrected QT interval and heart rate assessed from electrocardiogram among 4,588 older southern Chinese men in the Guangzhou Biobank Cohort Study (2003-2008). The F statistic was 77 for ALDH2 on alcohol use, suggesting little weak-instrument bias. Instrumental variable analysis showed that alcohol units were not associated with the corrected QT interval, with β = 1.04 (95% confidence interval: -0.61, 2.70) milliseconds, but they were associated with increased heart rate, with β = 0.98 (95% confidence interval: 0.04, 1.92) beat per minute. This study suggests that moderate alcohol use in men is not beneficial for heart function via QT interval or heart rate but could be detrimental. Future studies using specific cardiovascular outcomes may elucidate how alcohol affects different aspects of the cardiovascular system and, hence, the overall effects of alcohol on CVD can be estimated.

While Qiaocheng district currently is the main tobacco planting region in Northern Anhui Province, China, the quantitative assessment on spatial suitability for tobacco planting is necessary for the scientific instruction in the adjustment of planting regionalization and fertilization. In this paper, soil samples of the plough layers were collected from 1224 typical farmlands in 2008, and 18 types of soil properties, pH, clay, silt, sand, organic matter, total nitrogen, available phosphorus, slowly available potassium, rapidly available potassium, exchangeable Ca2+ and Mg2+, Cl-, HCO3-, SO42-, available Fe, Mn, Cu and Zn were measured. Meanwhile irrigation water samples of 90 typical pumping wells were collected, and Cl-, HCO3-, SO42-, K+, Ca2+ and Mg2+ were measured. The above measured properties were used as the assessing indexes for spatial suitability for tobacco planting, in which the weights were generated by the method of principal component analysis and the fuzzy membership functions were produced based on the practical experiences with the related literatures. The soil suitabilities were quantitatively assessed using the ArcGIS 10.0 platform. The experimental results showed that: (1) areas of the highest, higher, middle, lower and lowest levels of suitability are 4.28×104, 4.36×104, 4.82×104, 4.47×104 and 4.81×104 hm2. respectively, constituted of 18.84%, 19.16%, 21.20%, 19.66% and 21.14% of the total area of the farmland, respectively; (2) in general, the Northeast, Northwest, Southeast and Southwest regions are the most suitable areas, and (3) for tobacco farmland in the North region, more potassium fertilizers should be applied due to the low available potassium content in soil, and the flood irrigation should be prevented due to the high content of Cl- in irrigation water. Chengfu in the Sourtheast, Shihe and Feihe in the Southwest, and Longyang and Gucheng in the South could be regarded as the new potential tobacco planting regions.

Background QT interval prolongation, a predictor of cardiac arrhythmias, and elevated heart rate are associated with higher risk of cardiovascular mortality. Observationally testosterone is associated with shorter corrected QT interval and slower heart rate; however, the evidence is open to residual confounding and reverse causality. We examined the association of testosterone with electrocardiogram (ECG) parameters using a separate-sample instrumental variable (SSIV) estimator. Methods To minimize reverse causality, a genetic score predicting testosterone was developed in 289 young Chinese men from Hong Kong, based on a parsimonious set of single nuclear polymorphisms (rs10046, rs1008805 and rs1256031). Linear regression was used to examine the association of genetically predicted testosterone with QT interval, corrected QT interval [using the Framingham formula (QTf) and Bazett formula (QTb)] and heart rate in 4212 older (50þ years) Chinese men from the Guangzhou Biobank Cohort Study. Results Predicted testosterone was not associated with QT interval [� 0.08ms per nmol/l testosterone, 95% confidence interval (CI) � 0.81 to 0.65], QTf interval (0.40ms per nmol/l testosterone, 95% CI � 0.12 to 0.93) or heart rate (0.26 beats per minute per nmol/l testosterone, 95% CI � 0.04 to 0.56), but was associated with longer QTb interval (0.66ms per nmol/l testosterone, 95% CI 0.02 to 1.31). Conclusions Our findings do not corroborate observed protective associations of testosterone with QT interval or heart rate among men, but potentially suggest effects in the other direction. Replication in a larger sample is required.

Objective Few studies have systematically investigated the impact of past occupational dust exposure on mental health. We examined whether retired factory workers exposed to any of the 4 dusts of silica, cement, coal and asbestos had more depressive symptoms and anxiety in southern China, which has experienced rapid economic development. Methods We used data from the Guangzhou Biobank Cohort Study phase 3. Exposures, lifestyle, symptoms and medical history of the participants were assessed with a structured interview. Self-reported intensity and duration of past occupational dust exposure were used to derive cumulative exposure. Outcome measures were assessed by the 15-item Chinese version of the Geriatric Depression Scale (score ≥5) and the single-item on anxiety. Results The results revealed that 359 workers were exposed to at least one of the 4 dusts and that 1,253 were unexposed (controls). After adjustment of multiple confounders, greater risks of depressive symptoms were associated with high exposure to silica (odds ratio (OR) of 3.12, 95% CI of 1.17-8.31) and asbestos (OR of 6.90; CI of 1.29-36.75). Risks of anxiety were higher in those with low or high exposures to dust (OR of 2.01 and CI of 1.04-3.87 and OR of 2.29 and CI of 1.30-4.03, respectively) and cement (OR of 3.20 and CI of 1.27-8.07 and OR of 2.30 and CI of 1.09-4.87, respectively), and those with high exposure to silica (OR of 5.29, CI of 1.76-15.92). Conclusions Past occupational exposures to silica, cement, coal and asbestos dusts were associated with adverse mental health outcomes in retired factory workers. The mechanism underlying the relationship between occupational exposures and psychological symptoms in later life needs to be further studied.

This paper is to present an effective wireless power transfer (WPT) system to recharge the battery of electric unmanned aerial vehicle (e-UAV). The proposed system can generate an approximately even magnetic field which allows the e-UAV to get enough energy at different points above the charging pad. Also, based on the design, the proposed system is capable to transmit enough power at a high efficiency. Both simulation and experimentation are carried out to prove the validity of the proposed WPT system for e-UAV charging.

Introduction: The Chinese government’s implementation of the MPOWER policies and compliance with the WHO Framework Convention on Tobacco Control requirements has been slow. We used the ‘foot-in-the-door’ approach to promote tobacco control advocacy through capacity building of healthcare leaders, and establishment of smoking cessation clinics in Guangzhou and Beijing (two of the largest cities in China). Methods: This collaborative pilot project involved the University of Hong Kong and three major hospitals in Guangzhou and Beijing. A steering committee conducted the smoking cessation training workshops starting from April 2006, and set up three smoking cessation model clinics during August 2006 to October 2008. We followed up the trained health care professionals (HCPs) in 2014 and 2015 to assess their impacts on tobacco control beyond smoking cessation. Results: We emphasized the importance of the general tobacco control atmosphere during smoking cessation training of 139 HCPs to motivate them to engage in tobacco control advocacy. In addition to enhancing their knowledge and skills in cessation, the HCPs were then involved in the establishment of three in-hospital smoking cessation clinics and served as smoking cessation counselors since June 2008. Moreover, they ventured outside the clinics and the community to publicize smoking cessation. Their effort has contributed to smoke-free legislation, better surveillance on smoking and media advocacy on tobacco control in China. Conclusions: The training and establishment of smoking cessation clinics could serve as a means to motivate and empower HCPs who could contribute to broaden tobacco control policy in China.

Objective We examined the association between different adiposity indices and pulmonary function in Chinese adults in the Guangzhou Biobank Cohort Study (GBCS). Methods Participants with body mass index (BMI) low limits of normal and FVC % Results Of 16186 participants (mean age 61.4 ± 7.2 years; 74.0% women), 116 (0.7%) had only general obesity (BMI ≥28 kg/m2), 4079 (25.2%) had only central obesity (WC: ≥90 cm in men, ≥80 cm in women) and 1591 (9.8%) had both central obesity and general obesity. Comparing to those with neither central nor general obesity, those with only central adiposity and with both central and general obesity had lower pulmonary function (adjusted β range from -2.85 to -6.02 for FEV1% and FVC%, adjusted OR range from 1.14 to 1.70, all P 0.05). Both FEV1% and FVC% decreased per standard deviation increase in obesity indices (adjusted β from -0.46 to -3.17, all P Conclusion Central adiposity and its indices, but not general adiposity and BMI, were independently associated with lower pulmonary function and higher risk of restrictive respiratory defect in older Chinese.

With ever-increasing concerns for the safety and convenience of the power supply, there is a fast growing interest in wireless power transfer (WPT) for industrial devices, consumer electronics, and electric vehicles (EVs). As the resonant circuit is one of the cores of both the near-field and far-field WPT systems, it is a pressing need for researchers to develop a high-efficiency high-frequency resonant circuit, especially for the mid-range near-field WPT system. In this paper, an overview of resonant circuits for the near-field WPT system is presented, with emphasis on the non-resonant converters with a resonant tank and resonant inverters with a resonant tank as well as compensation networks and selective resonant circuits. Moreover, some key issues including the zero-voltage switching, zero-voltage derivative switching and total harmonic distortion are addressed. With the increasing usage of wireless charging for EVs, bidirectional resonant inverters for WPT based vehicle-to-grid systems are elaborated. Keywords: magnetic resonance; wireless power transfer; non-resonant converters; resonant inverters; compensation networks; selective resonant circuits

Aim Whether different adiposity measures predict incident diabetes differentially in general Chinese populations is unclear. We investigated this in Chinese people aged 50+ years in the Guangzhou Biobank Cohort Study. Methods Waist circumference and BMI were measured at baseline, and fasting glucose was measured at both baseline and follow-up examinations. Incident diabetes was defined as fasting glucose ≥ 7.0 mmol/l, glucose after 2-h oral glucose tolerance test ≥ 11.1 mmol/l, and/or self-reported physician-diagnosed diabetes during the follow-up period. Results Of 15 752 people without diabetes at baseline from 2003 to 2008, 1779 (11.3%) developed incident diabetes during the follow-up from 2008 to 2012 (mean = 3.6 years, sd = 1.0). After mutually adjusting each other and adjusting for other potential confounders, waist circumference showed a higher predictive value than BMI. The odds ratio (OR) (95% confidence interval (CI) was 1.50 (95% CI 1.37–1.64) for a 1 sd increment in waist circumference and 1.21 (95% CI 1.11–1.33), for a 1 sd increment in BMI. Similarly, after mutual adjustment, abdominal obesity was associated with an almost twofold odds of incident diabetes (OR 1.93, 95% CI 1.71–2.17), which was higher than that for general obesity (OR 1.76, 95% CI 1.50–2.06). The area under receiver operating characteristic curve (AUC) for waist circumference was higher than that for BMI [AUC = 0.676 (95% CI 0.660–0.686) vs. 0.665 (95% CI 0.651–0.678), P = 0.02]. Conclusion Abdominal obesity predicted incident diabetes in older people better than general obesity. Our findings may be an early warning signal for local government or public health practitioners to develop and investigate more effective intervention programmes for diabetes, and should also be disseminated to the public to pay more attention to this important public health issue. This article is protected by copyright. All rights reserved.

With the electric vehicle (EV) market growing fast, the emerging wireless EV charging technology has attracted more and more attention in recent years. As a key part of wireless charging system for EVs, the coil design is indispensable for improving the system performance. This paper presents an overview of coil designs for wireless charging of EVs, which addresses their basic structures, operating principles, and distinct features. The basic topologies including the circular rectangular pad (CRP), circular pad (CP), homogeneous pad (HP), double-D pad (DDP), double-D quadrature pad (DdQp), and bipolar pad (BP), are introduced and discussed. Also, the corresponding advantages and limitations of each topology are analyzed and discussed. Besides, some key issues of practical design problems are compared in the coil topologies. Finally, the human exposure issues are revealed.

To clarify the causal role of age at menarche in depressive symptoms we conducted a Mendelian randomization study using a large Southern Chinese cohort (n = 12,233). A genetic allele score was derived using stepwise regression with cross validation. Older age at menarche was not associated with geriatric depression scale score. Our findings suggest that higher rates of depression in women are likely attributable to other factors which require investigation.

This paper proposes and implements the concept of wireless DC motor drives, which can achieve the abilities of selective driving and controllable speed. Due to different resonant frequencies of the multiple energy receivers of the associated DC motor drives, the transmitter can be purposely tuned to the specified resonant frequency which matches with the specified receiver, hence driving the specified motor selectively. In the meantime, the burst fire control is used to regulate the operating speed of the motor working at the resonant frequency, hence retaining the maximum power transmission efficiency. Both finite element analysis and experimentation are given to verify the validity of the proposed wireless DC motor drive system. For exemplification, three different resonant frequencies, namely 60 kHz, 100 kHz and 140 kHz, are selected to energize three DC motors. Under the burst fire control method, the speed of each motor can be regulated separately and the wireless power transfer (WPT) system can achieve the measured power transmission efficiency of about 60%.

Purpose In Asia, moderate alcohol users have better lung function. Never users have more inactive aldehyde dehydrogenase 2 (ALDH2) alleles (A) potentially generating confounding because inactive alleles may increase acetaldehyde exposure and reduce lung function. Methods We examined the association of ALDH2 genotypes with percentage predicted lung function (forced expiratory volume in 1 second; forced vital capacity) for age, sex, and height among 5641 older Chinese using multivariable linear regression. Results ALDH2 genotypes were associated with alcohol use and height but not other attributes. Inactive alleles were inversely associated with lung function (percentage predicted forced expiratory volume in 1 second −1.52%, 95% confidence interval [CI], −2.52% to −0.51% for one inactive allele and −2.05%, 95% CI, −3.85% to −0.26% for two inactive alleles compared with two active alleles; and for percentage predicted forced vital capacity −1.25%, 95% CI −2.15% to −0.35% and −1.65%, 95% CI, −3.25% to −0.04%). The association of moderate use with lung function was attenuated after adjusting for ALDH2, in addition to other potential confounders. Conclusions Previous findings in Chinese may be confounded by ALDH2. High frequency of inactive ALDH2 alleles in East Asia may exacerbate the effect of environmental acetaldehyde exposure on lung function and potentially on chronic obstructive pulmonary disease.

This paper proposes and implements an all-in-one induction heating system, which can accommodate both pan-shaped and wok-shaped utensils. Traditionally, the pan is heated by a planar induction cooktop while the wok is heated by a curved induction cooktop. In this paper, both magnetic inductive coupling and magnetic resonant coupling are utilized to achieve excellent heating performance of the wok based on a planar primary coil. The key is to flexibly employ a detachable frustum coil for heating the wok. Specifically, the theoretical models of the proposed induction heating system with and without using the frustum coil are derived to analyze the proposed system. Computational simulation results of the magnetic and thermal fields of the proposed system are provided to elaborate the heating performance of the wok. A 1500 W prototype is designed and built. The calculated, simulated and experimental results are all in good agreement, which validate the feasibility of the proposed induction heating system well.

Objective The aim of this study was to analyze the associations between occupational stress, burnout and turnover intention and explore their associated factors among managerial staff in Guangzhou, China. Methods This cross-sectional study recruited 288 managerial employees from a Sino-Japanese joint venture automobile manufacturing enterprise in Guangzhou. The questionnaire included questions about sociodemographic characteristics, smoking, drinking and physical activity and the Chinese versio ns of the Occupational Stress Indicator (OSI), Maslach Burnout Inventory (MBI), Eysenck Personality Questionnaire (EPQ), Simplified Coping Style Questionnaire (SCSQ) and Social Support Rating Scale (SSRS). The response rate was 57.6%. Stepwise regression analysis was performed to examine the associations between burnout and occupational stress and turnover intention and related factors. Results The respondents had a high level burnout on the personal accomplishment subscale and had a high prevalence of turnover intention. Neuroticism, psychoticism, job satisfaction, occupational stress and social support were strong predictors of emotional exhaustion. Psychoticism, passive coping, occupational stress, objective support, utilization of support, male gender and job satisfaction were strong predictors of depersonalization. Active and passive coping and job satisfaction were strong predictors of personal accomplishment. Job dissatisfaction and emotional exhaustion were strong predictors of turnover intention. Conclusions High occupational stress and low job satisfaction were associated with high burnout, particularly in the emotional exhaustion and depersonalization dimensions. Low job satisfaction and high emotional exhaustion were associated with high turnover intention among employees. Personality traits, social support and coping style were also found to be associated with burnout.

To examine the association between serum uric acid (UA) levels and cardiovascular risk factors in subjects without diabetes or hyperuricemia.6172 women and 2662 men aged 50+ years without diabetes from Phase 1 of the Guangzhou Biobank Cohort Study were included. Data on personal history, physical examination and biochemical parameters were collected. Subjects were categorized by serum UA concentration, and the association between UA levels and cardiovascular risk factors was examined using generalized linear models.In both men and women with normouricemia (UA420 μmol/l in men and360 μmol/l in women), tertiles of UA levels were adversely associated with body mass index, waist circumference, waist-to-hip ratio, total- and HDL-cholesterol, apolipoprotein A1, systolic and diastolic blood pressures, pulse pressure, fasting plasma glucose and white blood cell count (P value for trend ranged from 0.04 to0.001), and also consistently associated with metabolic disorders including obesity, hypertension, hypertension treatment, dyslipidemia, waist circumference increased since the age of 18 years and the metabolic syndrome (P value for trend ranged from 0.02 to0.001).Increasing UA levels, even in subjects with normouricemia and without diabetes, were associated with increasing prevalence of cardiovascular risk factors, suggesting that clinically dichotomous definition of hyperuricemia may be inadequate and high-normal value of UA may warn of metabolic disorders.

Chinese people have a markedly lower alcohol consumption than people in the West. Whether alcohol consumption at such levels is associated with left ventricular hypertrophy, and the role of blood pressure (BP) in this relationship is unclear. We investigated the association between alcohol consumption and electrocardiographic left ventricular hypertrophy (ECG-LVH) and the mediating role of BP in Chinese men aged ≥50 years.A case-control analysis was conducted on baseline cross-sectional data from the community-based Guangzhou Biobank Cohort Study (2003-2008), using standard 12-lead resting electrocardiograms. By comparing 191 new ECG-LVH cases with 4311 controls, excessive drinking (210 g/week) showed excess risks for ECG-LVH (odds ratio [OR] = 1.90, 95% confidence interval [CI] = 1.12-3.24), after adjusting for education, income, occupation, physical activity, smoking, body mass index, fasting glucose, triglyceride, total cholesterol, high-density lipoprotein cholesterol, BP, and antihypertensive medication. Mediation analysis showed a significant mediating effect of BP on the association between excessive drinking and ECG-LVH: systolic (31%) and diastolic (16%). After multivariate adjustment, no significant association was found between occasional drinking (once/week: OR = 1.20, 95% CI = 0.80-1.80) and moderate drinking (≥once/week to ≤210 g/week: OR = 0.88, 95% CI = 0.53-1.47) with increased/decreased risk of ECG-LVH.Alcohol consumption at210 g/week in Chinese men is an independent risk factor for ECG-LVH. Low power prevented us from examining whether drinking atonce/week to ≤210 g/week is associated with decreased/increased risk of ECG-LVH. Elevated BP partially mediates between alcohol and ECG-LVH. A Mendelian randomization approach with a large sample size is warranted to determine the relations among alcohol consumption, BP, and LVH.

The effects of alcohol dehydrogenase (ADH) 2 and aldehyde dehydrogenase (ALDH) 2 genotypes on the alcohol–blood pressure association are unclear. We examined the association of ADH2 or ALDH2 genotypes with blood pressure in older Chinese men. Based on the Guangzhou Biobank Cohort Study (GBCS), 4792 men with valid ADH2, ALDH2 genotypes were included, and genotyping of rs1229984 ADH2 and rs671 ALDH2 (AA, AG/GA or GG) was performed using a Sequenom Mass-Array platform. Information on socio-demographics and lifestyle factors, including alcohol use, was obtained from a questionnaire, and blood pressure was measured. Among alcohol drinkers, systolic and diastolic blood pressure (SBP and DBP) and mean arterial pressure (MAP) were highest for men with the GG ADH2 genotype (136.6, 77.9 and 97.5 mm Hg, respectively), followed by those with the (AA/AG ADH2+GG ALDH2) genotype (133.4, 77.6 and 96.2 mm Hg, respectively) and then the (AA/AG ADH2+AA/AG ALDH2) genotype (SBP=132.6, DBP=76.6 and MAP=95.2 mm Hg) (P for trend ranged 0.025–0.035). After adjustment for potential confounders, as well as frequency or amount of alcohol use, men with the GG ADH2 genotype were more likely to have hypertension (odds ratio (OR)=1.62, 95% confidence interval 1.15–2.28) as were men with the (AA/AG ADH2+AA/AG ALDH2) genotype (OR=1.40, 95% confidence interval 1.01–1.96) compared with men with the (AA/AG ADH2+GG ALDH2) genotype). ADH2 or ALDH2 genotypes were unrelated to hypertension among those who never drink alcohol. ADH2 genotype influences blood pressure and risk of hypertension among male alcohol drinkers, suggesting that the hypertensive effect of alcohol is due to ethanol rather than acetaldehyde.

Objective To examine the association between alcohol consumption and aortic arch calcification (AAC) in an older Chinese sample. Methods In 27,844 older people aged 50–85, socioeconomic position and lifestyle factors were assessed by a questionnaire. The presence and severity of AAC were diagnosed from chest X-ray by two experienced radiologists. Results In men, the risk for AAC increased significantly in frequent or excessive drinkers [adjusted odds ratio (OR)=1.36 (95% confidence interval (CI) 1.16–1.59) and 1.49 (1.21–1.83) for those who drank >5times/week and those who drank excessively, respectively] (P for trend from 0.002 to 0.001). When AAC was analyzed as an outcome variable with 3 categories of severity, significant dose–response relations between the severity of AAC and alcohol consumption were observed, with those who drank frequently (>5/week) or excessively having more serious AAC (P for trend=0.03 and 0.02, respectively). No significant association was found in women as few drank excessively. Conclusion The presence and severity of AAC were associated with quantity or frequency of alcohol consumption in a dose–response pattern, suggesting that alcohol drinking, even when moderate, has no benefit for AAC. Excessive drinking increased the risk of AAC by 50% compared to never drinkers.

Background: There is consistent evidence of the co-occurrence of poor mental health and asthma in Western populations. Since the experience and expression of mental health is partly culturally determined, it is of interest to examine if similar associations are found in other cultural settings. In that regard, very little is known about the association between mental health and asthma in Asian countries, such as China.Purpose: The aim of this study was to investigate the relationship between mental health and asthma in a large sample from China.Method: We used data from the Guangzhou Biobank Cohort Study phase 3 (n = 9,280). Participants reported physician-diagnosed asthma. Mental health measures included the 15-item Chinese version of the Geriatric Depression Scale (GDS-C) and the SF-12 Mental Component Summary (MCS) score. We compared the prevalence of asthma by GDS-C and MCS scores by estimating prevalence ratios (PRs) and their corresponding 95% confidence intervals (95% CI), using Poisson regression.Results: Compared to those without depression, the prevalence of asthma was higher in those with moderate or severe depression levels (PR = 2.63, 95% CI = 1.58-4.40 and PR = 4.43, 95% CI = 1.62-12.09, p for trend ≤0.0001). The prevalence of asthma increased by 46% with every 1 standard deviation increase of the GDS-C score (PR = 1.46, 95% CI = 1.24-1.73). The MCS score was not associated with asthma.Conclusion: Depressive symptoms were associated with asthma prevalence in a Chinese population. Further research into the mechanism and potential directions of causality is warranted.

The aim of this study was to examine the relationship between seated resting heart rate and the metabolic syndrome (MetS) among older residents of Guangzhou, South China. A total of 30,519 older participants (≥50 years) from the Guangzhou Biobank Cohort Study were stratified into quartiles based on seated resting heart rate. The associations between each quartile and the MetS were assessed using multivariable logistic regression. A total of 6,907 (22.8 %) individuals were diagnosed as having the MetS, which was significantly associated with increasing heart rate quartiles (P < 0.001). Participants in the uppermost quartile (mean resting heart rate 91 ± 8 beats/min) of this cardiovascular proxy had an almost twofold increased adjusted risk (odds ratio (95 % CI) = 1.94 (1.79, 2.11), P < 0.001) for the MetS, as compared to those in the lowest quartile (mean resting heart rate, 63 ± 4 beats/min). Heart rate, which is an inexpensive and simple clinical measure, was independently associated with the MetS in older Chinese adults. We hope these observations will spur further studies to examine the usefulness of resting heart rate as a means of risk stratification in such populations, for which targeted interventions should be implemented.

Objectives We studied the association between secondhand smoke (SHS) exposure and peripheral arterial disease (PAD) in Chinese non-smokers. Methods We conducted a cross-sectional study using baseline data from the Guangzhou Biobank Cohort Study: Cardiovascular Disease Sub-cohort Study (GBCS-CVD). Guangzhou residents aged ≥ 50 years were recruited between 2003 and 2008. Baseline data included measurement of ankle brachial pressure index (ABPI) and self-reported smoking status and SHS exposure. Univariate and multivariate logistic regression analyses were used to analyze the association between SHS and PAD (defined as ABPI Results Of the 1507 non-smokers, 24 (1.6%) had PAD. Of these, 12 were men and 12 were women. Exposure to SHS at home of ≥25 h per week was reported by 16.7% of PAD cases compared with 3.8% of those without PAD (χ2 test, p = 0.003). After adjustment for potential confounders, exposure to ≥25 h per week at home was still associated with PAD (adjusted OR 7.86, 95% CI 2.00–30.95, p = 0.003), with suggestion of a dose-response relationship. Conclusions Our results extend the US Surgeon General’s 2006 report that SHS exposure is an independent risk factor for PAD. National smoke-free legislation is needed to protect all people from exposure.

Observational studies of the association of alanine aminotransferase (ALT) levels with ischaemic heart disease (IHD) and cardiovascular disease (CVD) risk factors are inconsistent, probably because of confounding and reverse causality. Mendelian randomization (MR) provides less confounded results. We used MR analysis to assess the associations of ALT (U/L) with IHD, diabetes and other CVD risk factors. We used instrumental variable analysis based on two single nucleotide polymorphism (SNPs) HSD17B13/MAPK10 (rs6834314) and PNPLA3/SAMM50 (rs738409) to assess the associations of ALT (U/L) with IHD, diabetes and other CVD risk factors in the Guangzhou Biobank Cohort Study (GBCS). Observationally in 19,925 participants ALT levels were strongly positively associated with self-reported IHD, systolic and diastolic blood pressure, low-density lipoprotein- and total cholesterol, triglycerides, fasting glucose, body mass index, waist circumference, heart rate (HR) and diabetes, but were not associated with uncorrected QT interval, HR-corrected QT interval or high-density lipoprotein-cholesterol. In the MR study, using a credible genetic instrument (F-statistic = 23) for ALT, ALT levels were negatively associated with IHD (odds ratio (OR) 0.92, 95% confidence interval (CI) 0.87 to 0.97) and triglycerides (β - 0.08, 95% CI - 0.13 to - 0.03), but were not associated with other CVD risk factors. Our results using Mendelian randomization suggest that ALT reduces the risk of IHD, probably through reducing triglyceride levels. The underlying mechanisms deserve further investigation.

The mechanism of selenium-mediated salt tolerance has not been fully clarified. This study investigated the possible role of selenium (Se) in regulating maize salt tolerance. A pot experiment was conducted to investigate the role of Se (0, 1, 5 and 25 μM Na2SeO3) in photosynthesis, antioxidative capacity and ion homeostasis in maize under salinity. The results showed that Se (1 μM) relieved the salt-induced inhibitory effects on the plant growth and development of 15-day-old maize plants. Se application (1 μM) also increased the net photosynthetic rate and alleviated the damage to chloroplast ultrastructure induced by NaCl. The superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities were increased, and ZmMPK5, ZmMPK7 and ZmCPK11 were markedly up-regulated in the roots of Se-treated plants, likely contributing to the improvement of antioxidant defence systems under salinity. Moreover, 1 μM Se increased K+ in the shoots while decreasing Na+ in the roots, indicating that Se up-regulates ZmNHX1 in the roots, which may be involved in Na+ compartmentalisation under salinity. The findings from this single experiment require repetition together with measurement of reactive oxygen species (ROS), but nevertheless suggest that exogenous Se alleviates salt stress in maize via the improvement of photosynthetic capacity, the activities of antioxidant enzymes and the regulation of Na+ homeostasis.

Genome-wide association studies (GWASs) have identified many common type 2 diabetes-associated variants, mostly at the intronic or intergenic regions. Recent advancements of exome-array genotyping platforms have opened up a novel means for detecting the associations of low-frequency or rare coding variants with type 2 diabetes. We conducted an exomechip association analysis to identify additional type 2 diabetes susceptibility variants in the Chinese population.An exome-chip association study was conducted by genotyping 5640 Chinese individuals from Hong Kong, using a custom designed exome array, the Asian Exomechip. Single variant association analysis was conducted on 77,468 single nucleotide polymorphisms (SNPs). Fifteen SNPs were subsequently genotyped for replication analysis in an independent Chinese cohort comprising 12,362 individuals from Guangzhou. A combined analysis involving 7189 cases and 10,813 controls was performed.In the discovery stage, an Asian-specific coding variant rs2233580 (p.Arg192His) in PAX4, and two variants at the known loci, CDKN2B-AS1 and KCNQ1, were significantly associated with type 2 diabetes with exome-wide significance (pWe identified the association of a PAX4 Asian-specific missense variant rs2233580 with type 2 diabetes in an exome-chip association analysis, supporting the involvement of PAX4 in the pathogenesis of type 2 diabetes. Our findings suggest PAX4 is a possible effector gene of the 7q32 locus, previously identified from GWAS in Asians.