42 research outputs found
Impacts of undetected and inadequately treated hypertension on incident stroke in China
OBJECTIVES: China carries the greatest burden of stroke given its largest volume of people with hypertension. This study assessed the impacts of suboptimal controls of hypertension on incident stroke and projected the number of patients with stroke saved after the control of blood pressure improved in population. SETTING: Anhui, China. PARTICIPANTS: We examined data from the Anhui cohort of 2001-2011, consisting of 3336 participants aged ≥60 years who were randomly recruited from the urban and rural Anhui. 2852 participants (89.2%) had hypertensive status measured and no stroke at baseline, and were followed up until 2011 in three surveys using a standard method of interview. RESULTS: At baseline, 1646 participants (57.7%) were identified to have hypertension, among whom 912 (55.4%) were previously undetected, 115 (7.0%) detected but not treated, 452 (27.5%) treated but not controlled and only 127 (7.7%) controlled. During the 10-year follow-up, 211 incident stroke cases (12.8/1000 person-years) occurred. Compared with normotensive individuals at baseline, multivariate adjusted HR for having stroke increased in those with undetected hypertension by 1.63 (95%CI 1.15 to 2.32), untreated by 2.21 (1.26-3.85) and uncontrolled hypertension by 3.34 (2.28-4.88), but did not differ from those with controlled hypertension (1.34; 0.60-2.99). Based on a two-fold increase in the detection and management of current levels of hypertension and algorithms on the current situation in China, approximately 250 000 incident stroke cases could be prevented annually. CONCLUSIONS: In China, hypertension is frequently undetected or inadequately treated. With appropriate management of hypertension, a substantial number of people could be saved form stroke
Prevalence of internet addiction and its association with stressful life events and psychological symptoms among adolescent internet users
Internet addiction (IA) among adolescents is a serious public health problem around the world. However, there have been few studies that examine the association between IA and stressful life events and psychological symptoms among Chinese adolescent internet users. We examined the association between IA and stressful life events and psychological symptoms among a random sample of school students who were internet users (N = 755) in Wuhan, China. Internet addiction, stressful life events, coping style and psychological symptoms were measured by self-rated scales. The prevalence rate of internet addiction was 6.0% among adolescent internet users. Logistic regression analyses indicated that stressors from interpersonal problem and school related problem and anxiety symptoms were significantly associated with IA after controlling for demographic characteristics. Analyses examining the coping style with the IA revealed that negative coping style may mediate the effects of stressful life events to increase the risk of IA. However, no significant interaction of stressful life events and psychological symptoms was found. These findings of the current study indicate a high prevalence of internet addiction among Chinese adolescent internet users and highlight the importance of stressors from interpersonal problem and school related problem as a risk factor for IA which mainly mediated through negative coping style.Published versio
Correlation-driven eightfold magnetic anisotropy in a two-dimensional oxide monolayer.
Engineering magnetic anisotropy in two-dimensional systems has enormous scientific and technological implications. The uniaxial anisotropy universally exhibited by two-dimensional magnets has only two stable spin directions, demanding 180° spin switching between states. We demonstrate a previously unobserved eightfold anisotropy in magnetic SrRuO3 monolayers by inducing a spin reorientation in (SrRuO3)1/(SrTiO3) N superlattices, in which the magnetic easy axis of Ru spins is transformed from uniaxial 〈001〉 direction (N < 3) to eightfold 〈111〉 directions (N ≥ 3). This eightfold anisotropy enables 71° and 109° spin switching in SrRuO3 monolayers, analogous to 71° and 109° polarization switching in ferroelectric BiFeO3. First-principle calculations reveal that increasing the SrTiO3 layer thickness induces an emergent correlation-driven orbital ordering, tuning spin-orbit interactions and reorienting the SrRuO3 monolayer easy axis. Our work demonstrates that correlation effects can be exploited to substantially change spin-orbit interactions, stabilizing unprecedented properties in two-dimensional magnets and opening rich opportunities for low-power, multistate device applications
MCR-ALS-based muscle synergy extraction method combined with LSTM neural network for motion intention detection
IntroductionThe time-varying and individual variability of surface electromyographic signals (sEMG) can lead to poorer motor intention detection results from different subjects and longer temporal intervals between training and testing datasets. The consistency of using muscle synergy between the same tasks may be beneficial to improve the detection accuracy over long time ranges. However, the conventional muscle synergy extraction methods, such as non-negative matrix factorization (NMF) and principal component analysis (PCA) have some limitations in the field of motor intention detection, especially in the continuous estimation of upper limb joint angles.MethodsIn this study, we proposed a reliable multivariate curve-resolved-alternating least squares (MCR-ALS) muscle synergy extraction method combined with long-short term memory neural network (LSTM) to estimate continuous elbow joint motion by using the sEMG datasets from different subjects and different days. The pre-processed sEMG signals were then decomposed into muscle synergies by MCR-ALS, NMF and PCA methods, and the decomposed muscle activation matrices were used as sEMG features. The sEMG features and elbow joint angular signals were input to LSTM to establish a neural network model. Finally, the established neural network models were tested by using sEMG dataset from different subjects and different days, and the detection accuracy was measured by correlation coefficient.ResultsThe detection accuracy of elbow joint angle was more than 85% by using the proposed method. This result was significantly higher than the detection accuracies obtained by using NMF and PCA methods. The results showed that the proposed method can improve the accuracy of motor intention detection results from different subjects and different acquisition timepoints.DiscussionThis study successfully improves the robustness of sEMG signals in neural network applications using an innovative muscle synergy extraction method. It contributes to the application of human physiological signals in human-machine interaction
Sexual Knowledge, attitudes and behaviors among unmarried migrant female workers in China: a comparative analysis
<p>Abstract</p> <p>Background</p> <p>In recent years, many studies have focused on adolescent's sex-related issues in China. However, there have been few studies of unmarried migrant females' sexual knowledge, attitudes and behaviors, which is important for sexual health education and promotion.</p> <p>Methods</p> <p>A sample of 5156 unmarried migrant female workers was selected from three manufacturing factories, two located in Shenzhen and one in Guangzhou, China. Demographic data, sexual knowledge, attitudes and behaviors were assessed by self-administered questionnaires. Multivariate logistic regression analysis was conducted to examine the factors associated with premarital sexual intercourse.</p> <p>Results</p> <p>The average age of the unmarried female workers included in the sample was 20.2 years, and majority of them showed a low level of sex-related knowledge. Females from the west of China demonstrated a significant lower level of sex-related knowledge than those from the eastern or central provinces (<it>p </it>< 0.05). Approximately 13% of participants held a favorable attitude towards premarital sexual intercourse, and youths from the east/central were more likely to have favorable attitudes compared with those from the west (<it>p </it>< 0.05). About 17.0% of the unmarried female workers reported having engaged in premarital sexual intercourse, and females from the east/central were more likely to have experienced premarital sexual intercourse than those from the west (<it>p </it>< 0.05). Multivariate analysis revealed that age, education, current residential type, dating, sexual knowledge, attitudes, and pattern of communication were significantly associated with premarital sexual intercourse.</p> <p>Conclusion</p> <p>The unmarried migrant female workers lack sexual knowledge and a substantial proportion of them are engaged in premarital sexual behaviors. Interventions aimed at improving their sexual knowledge and related skills are needed.</p
Prevalence of and risk factors for non-suicidal self-injury in rural China: Results from a nationwide survey in China
Background
Non-suicidal self-injury (NSSI) is a highly prevalent and serious public health problem among adolescents worldwide. However, to date there were no studies assessing the prevalence of NSSI defined by suggested DSM-5 criteria among Chinese adolescents. We aimed to conduct a nationwide survey to explore the prevalence of and risk factors for NSSI among school-based adolescents in rural China.
Methods
A total sample of 15,623 adolescents in rural China were enrolled by using a multistage sampling method. Data was collected by self-report questionnaires including demographic characteristics, neglect, maltreatment, loneliness, resilience, social support and emotional management ability. NSSI was defined by suggested DSM-5 criteria, according to which the engagement in self-injury took place more than 5 times a year. Multinomial logistic regression models were used to estimate the association between risk factors and NSSI.
Results
There were 12.2% of adolescents (n = 1908) met the suggested DSM-5 criteria. Approximately 29% reported a history of NSSI at least once during the last year. Significant differences were found in several demographic factors including gender, ethnicity, grade, and family structure between adolescents with and without experiencing NSSI. The top three NSSI behaviors among adolescents with NSSI experience were hitting self, pinching, and pulling hair, with a prevalence rate of 16.7%, 14.1% and 11.2%, respectively. Female, Han ethnicity, fathers’ education level, neglect, maltreatment, loneliness, social support, suicidal behaviors and emotional management ability were significantly associated with NSSI by multivariate analysis. No significant relationship was found between resilience and risk of NSSI.
Limitation
The DSM-5 has proposed 6 groups of criteria for NSSI, we only used criteria on frequency given its more accepted feasibility and pragmatic application. Consequently, it may different from other prevalence that estimated by other criteria.
Conclusion
To the best of our knowledge, this is the first study reporting prevalence of NSSI defined by suggested DSM-5 criteria among adolescent in rural China. In comparison to finding from the similar samples of adolescents, Chinese rural adolescents seem to have a relative higher prevalence. The potential risk factors for NSSI include female, father's education, Han ethnicity, psychosocial factors and suicide behaviors. More evidence for further understanding of context of the occurrence, improving access to health care utilization, and identifying the role of psychosocial factors and family relationship, is needed for the prevention and management of NSSI.Published versio
Features of X-Band Radar Backscattering Simulation Based on the Ocean Environmental Parameters in China Offshore Seas
The X-band marine radar has been employed as a remote sensing tool for sea state monitoring. However, there are few literatures about sea spectra considering both the wave parameters and short wind-wave spectra in China Offshore Seas, which are of theoretical and practical significance. Based on the wave parameters acquired from the European Centre for Medium-Range Weather Forecasts reanalysis data (ERA-Interim reanalysis data) during 36 months from 2015 to 2017, a finite depth sea spectrum considering both wind speeds and ocean environmental parameters is established in this study. The wave spectrum is then built into a modified two-scale model, which can be related to the ocean environmental parameters (wind speeds and wave parameters). The final results are the mean backscattering coefficients over the variety of sea states at a given wind speed. As the model predicts, the monthly maximum backscattering coefficients in different seas change slowly (within 4 dB). In addition, the differences of the backscattering coefficients in different seas are quite small during azimuthal angles of 0° to 90° and 270° to 360° with a relative error within 1.5 dB at low wind speed (5 m/s) and 2 dB at high wind speed (10 m/s). With the method in the paper, a corrected result from the experiment can be achieved based on the relative error analysis in different conditions