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The geomagnetically induced current (GIC) produced during extreme geomagnetic storms can easily lead to large‐scale blackouts in China due to the increase in the scale of its electric power grid. A power grid's resilience is its capability to resist various natural hazards, withstand primary failures, and quickly resume normal operation. To avoid power grid damages, this study developed a resilient power grid, incorporating failure, power flow calculation and recovery models under a uniform induced geoelectric field. We chose a system's performance loss as the resilience evaluation indicator, which intuitively reflected a system's loss under GIC. In addition, the recovery model was optimized using a genetic algorithm, and two resilience improvement measures were proposed. The IEEE‐RTS‐79 system, consisting of 10 generators, 24 buses and 5 transformers, was chosen as an example to verify the feasibility of this study. The results show that the genetic algorithm and optimization measures effectively enhanced the system's resilience indicator and provided a reference for preventing system damages under GIC and quick recovery after possible failures. Plain Language Summary: Extreme space weather produces large geomagnetic field disturbances; these disturbances propagate down to Earth, inducing secondary geomagnetically induced currents (GICs) in earthed electric power grids. GICs increase transformers' reactive power loss and raise their temperatures; this affects a power system's normal operation, and in extreme cases causes major blackouts. Therefore, it is vital to study power grids' resilience under GIC events. In this study, we calculated the GIC level using a uniform geoelectrical conductivity model. Based on this, we proposed a resilient power grid model consisting of the failure model, power flow calculation model and recovery model, and evaluated optimization strategies. Our results show that the proposed model can improve a power system's recovery performance after possible failure due to GICs and effectively avoid GIC‐related large‐scale blackouts. Key Points: We proposed a resilience assessment method for transmission systems under extreme space weatherWe calculated a resilience indicator and identified multiple effective methods to improve a system's resilienceWe chose the IEEE‐RTS‐79 system as an example to verify the effectiveness of a genetic algorithm and optimization measures [ABSTRACT FROM AUTHOR]

The present cross-sectional study was conducted to assess and compare the prevalence of dental caries of 229 deaf adolescents in a special senior high school and to identify factors related to dental caries, with a match group of 196 healthy adolescents in a normal senior high school, in Jiangsu province of East China. In this study the prevalence of dental caries was 55.9%, Decayed, Missing and Filled Teeth (DMFT) index in deaf students was 1.40 [plus or minus] 1.89; in healthy students was 13.8% and 1.36 [plus or minus] 1.72, respectively. Relatively lower proportion of awareness on dental health knowledge and lower proper practice of dental health behavior have been observed among deaf students compared with the control group. Multiple logistic regressions showed that the risk factors of dental caries in deaf students involved high frequency of consuming dessert and carbonated beverage. Poor oral health, lack of oral health knowledge and proper oral health practice could be found in deaf students. The dental treatment for the two groups was urgently needed. The dental health education concerning dietary behavior and prevention program to the deaf students and their parents should be reinforced; the supervision of oral health behavior for deaf and healthy students needs to be strengthened. (Contains 5 tables.)

Background: The aim of this study was to better understand methicillin-resistant Staphylococcus aureus (MRSA) at the molecular level by investigating the genotypic characteristics and evolutionary patterns of MRSA clones in Shenyang, China. Methods: We analyzed the molecular epidemiology of 60 MRSA isolates in Shenyang, China, between 2002 and 2008, using pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCC mec) typing, and S. aureus protein A ( spa) typing. They were examined for their antimicrobial susceptibilities. Results: Among the 60 isolates, ST239 was identified most frequently (34 isolates; 58%), followed by ST5 (20 isolates; 34%). Nine spa types were obtained and 4 PFGE strain families (A, B, C, and D) were resolved. Spa type t030, which corresponded to PFGE genotypes A1, A3, and A4, constituted 45% (27/60) of all isolates; spa type t037, which corresponded to PFGE type A2, accounted for 13% (8/60) of all isolates. These 2 spa genotypes belonged to ST239 and carried SCC mec type III. Isolates genotyped as spa type t002 comprised 27% (16/60) of the study set and included isolates typed as PFGE B1 and B2, ST5, and SCC mec II. Most of MRSA isolates belonging to ST239 were susceptible to trimethoprim-sulfamethoxazole. The minimum inhibitory concentration (MIC50) of vancomycin among MRSA isolates belonging to ST5 (2 mg/l) was higher than that for other isolates (1 mg/l). Conclusions: These data document 2 major epidemic MRSA clones in Shenyang, China: ST239-MRSA-SCC mec type III-t037/t030 and ST5-MRSA-SCC mec type II-t002. [ABSTRACT FROM AUTHOR]

Background: The World Health Organization reported in 2011that irrational use of medicines was a serious global problem that is wasteful and harmful. The worst is use of ineffective or harmful interventions which should not be used at all. However, little is known about the changes that 20 years of evidence-based medicine has made particularly in reducing use of ineffective interventions. We surveyed clinicians in China to show how often ineffective interventions were still used in practice. Methods: 3,246 clinicians from 24 tertiary hospitals were surveyed in person and another 3,063 through an online survey between 2006–2007. The main outcomes are prescription by a clinician, and use in a patient of, an ineffective intervention and of a matched effective intervention in patients with the same disease. 129 ineffective interventions for 68 diseases were identified from the BMJ Clinical Evidence and included in the survey. One effective intervention was identified for each disease and a total of 68 effective interventions were thus also included. The frequency of use of effective interventions was used as a reference for that of ineffective intervention. Results: The mean prescription rate by clinicians is 59.0% (95% confidence interval (95% CI): 58.6% to 59.4%) and 81.0% (95% CI: 80.6% to 81.4%) respectively for ineffective and effective interventions. The mean frequency of use in patients is 31.2% (95% CI: 30.8% to 31.6%) and 56.4% (95% CI: 56.0% to 56.8%) for ineffective and effective interventions respectively. The relative reduction in use of ineffective interventions as compared with that of matched effective interventions is 27.2% (95% CI: 27.0% to 27.4%) and 44.7% (95% CI: 44.3% to 45.1%) for clinician's prescription and use in patients respectively. 8.6% ineffective interventions were still routinely used in practice. Conclusions: Ineffective interventions were still commonly used. Efforts are necessary to further reduce and eventually eliminate ineffective interventions from practice. [ABSTRACT FROM AUTHOR]

The present cross-sectional study was conducted to assess and compare the prevalence of dental caries of 229 deaf adolescents in a special senior high school and to identify factors related to dental caries, with a match group of 196 healthy adolescents in a normal senior high school, in Jiangsu province of East China. In this study the prevalence of dental caries was 55.9%, Decayed, Missing and Filled Teeth (DMFT) index in deaf students was 1.40±1.89; in healthy students was 13.8% and 1.36±1.72, respectively. Relatively lower proportion of awareness on dental health knowledge and lower proper practice of dental health behavior have been observed among deaf students compared with the control group. Multiple logistic regressions showed that the risk factors of dental caries in deaf students involved high frequency of consuming dessert and carbonated beverage. Poor oral health, lack of oral health knowledge and proper oral health practice could be found in deaf students. The dental treatment for the two groups was urgently needed. The dental health education concerning dietary behavior and prevention program to the deaf students and their parents should be reinforced; the supervision of oral health behavior for deaf and healthy students needs to be strengthened. [Copyright &y& Elsevier]

This paper aims to analyze the goals and objectives of the policies for marine ranching management. Content analysis was used to code the marine ranching management policies. The paper reviews the policies from three areas according to the definitions of marine ranching: proliferation and release, artificial reefs, and marine ranching. Correspondingly, the performances of the results of the investigation of the goals and objectives were analyzed: the high-level goals mostly focused on construction or management, and they were especially focused on construction. The gap between the centralized and local high-level goals was obvious and the goals and objectives were mostly time-bounded and indicated the expected results but not were measurable or assignable. According to the investigation results, this paper summarizes the prospects for the future. To improve the quality and speed of marine ranching development and prevent confusion during implementation, two-way communication between the central and local governments and overall management of central government to close the gap between the goals and objectives, pay more attention to management after construction, assignable and indirect measurable goals and objectives and a management plan should be considered in the future. • The high-level goals mostly focused on construction or management. • The gap between the centralized and local high-level goals was obvious. • Goals and objectives need be assignable and measurable. • A management plan can be considered. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to measure the basal energy expenditure (BEE) of Chinese healthy adults and establish an accurate predictive equation for this population., Methods: In total, 470 Chinese healthy adults had their BEE measured using the Cosmed K4b 2 portable metabolic system. Multiple linear regression analysis was applied to develop new optimal equations for predicting BEE. The bias, accuracy rate, concordance correlation coefficient (CCC), and root mean square error (RMSE) were used to evaluate the accuracy of the predictive equations., Results: There was a significant difference in BEE between males and females, with 5,954 kJ/d and 5,089 kJ/d, respectively. People living in rural areas expended significantly higher BEE (5,885 kJ/d) than those in urban areas (5,279 kJ/d). Previous equations developed by Henry, Schofield, Harris-Benedict (H-B), and Liu overestimated the BEE of Chinese healthy adults. The new equations derived from the present study displayed the smallest average bias and RMSE from the measured basal energy expenditure (mBEE). The CCC of the new equations was higher than other predictive equations, but it was lower than 0.8. There was no significant difference in the accuracy rate among all predictive equations., Conclusions: Sex and regional differences in BEE were observed in Chinese healthy adults. Neither the widely used previous predictive equations nor the one derived in the present study were accurate enough for estimating the BEE of Chinese healthy adults. Further study is required to develop more accurate equations for predicting the BEE of Chinese healthy adults aged between 20-45 years., (Copyright © 2020 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.)

This cross-sectional survey assessed both risk and prevention of health care workers to bloodborne virus transmission in 2 hospitals in Beijing. The identified discrepancy between the high level of occupational blood exposure and suboptimal compliance with standard precautions underscores the urgent need for interventions to enhance occupational safety of health care workers in China., (Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.)

Objective: To assess the improvement of intelligence quotient through an Universal Salt Iodization Supply Program, among children., Methods: 3518 and 1611 children were selected from primary schools in Linxia Hui Autonomous Prefecture of Gansu in 2006 and 2010 respectively. Intelligence quotient (IQ) were measured by the revised Chinese Combined Raven Test-C2 (CRT-C2)., Results: In 2006, the average IQ of children aged 8-10 was 85.1, including 16.7% of them with IQ ≤ 69. The average IQ was between 80-90 in different counties and cities, with significant differences (P < 0.05). The average IQs were 92.0, 90.6 and 81.8 among 8, 9 and 10 years old children respectively with 10 year old's low than those 8 and 9 year olds (P < 0.05). The average IQs of boys and girls were 84.5 and 85.6, but with no significant difference (P > 0.05). The average IQ of children aged 8-10 in 2010 was 97.2 and 12 points higher than in 2006 (P < 0.05), but 8 IQ points (P < 0.05) less than the average level 105 from the overall of Gansu province. 4.7% of the children having an IQ ≤ 69. IQ of children from Linxia city and Yongjing county, were up to the theoretical level of 100, with an average IQ at around 95 in other counties. The average IQs between counties or cities showed significant differences. The IQ of 8, 9 year olds and 10 year olds did not present significant difference (P > 0.05), but in boys (98.8) and in girls (95.9) the difference was significant (P < 0.05)., Conclusion: The average IQ was close to the theoretical level (100) with the gradual implementation of universal salt iodization program, showing that the iodized salt did play a key role on children's intelligence. However, the average IQ was still lower than the average level of the whole Gansu province in 2010.

Background: Evidence-based medicine has come into its second decade. How prepared clinicians are in practicing it in particular in developing countries remains unclear. Thus we conducted this survey of physicians in urban hospitals in China to determine the size of the gap between research evidence and physicians' knowledge and practice regarding antihypertensive drugs for primary prevention of cardiovascular diseases in China., Methods: A cross sectional survey by a face-to-face interview was conducted in 20 tertiary general hospitals in China in 2005. A total of 444 physicians (mostly cardiologists) in internal medicine who had treated at least one hypertensive patient in the past 12 months were invited for the interview on their perception of the cardiovascular risk of hypertension, the magnitude of the benefit of antihypertensive drugs, knowledge on the overall risk approach, first-line drugs used, the risk above which drug treatment is recommended, and knowledge on evidence-based medicine., Results: A total of 444 of the 468 eligible physicians were successfully interviewed with a response rate of 94.9%. They estimated that a hypertensive man with an actual 5-year cardiovascular risk of 8.4% would have a 5-year cardiovascular risk of 40% (95%CI: 38% to 42%) if not treated, and have an absolute risk reduction and relative risk reduction from drug treatment by 20% (95%CI: 18% to 22%) and 39% (95%CI: 37% to 42%) respectively, as compared to 3.3% and 33% respectively shown in research evidence. On average, the physicians would recommend drug treatment at a number needed to treat (NNT) of 368 or smaller, as compared to the actual NNT of 50 for drug treatment in an average hypertensive Chinese. Fifty-five percent (95%CI: 50% to 59%) of them had never intently used the national hypertension guidelines. The majority still prescribed drugs primarily based on blood pressure alone by ignoring other risk factors or the overall risk and 78% (95 % CI: 76% to 83%) used new expensive drugs such as calcium channel blockers and angiotensin converting enzyme (ACE) inhibitors as first-line treatment. Only 13% (95%CI: 9% to 18%) could correctly interpret the NNT. Forty-three percent (95%CI: 39% to 48%) did not know the randomized controlled trial was scientifically the most rigorous among other study designs for evaluating the effectiveness of anti-hypertensive drugs. Ninety-two percent (95%CI: 90% to 94%) did not know they could start by searching systematic reviews when looking for evidence on the effectiveness of anti-hypertensive drugs as opposed to trials. Ninety-six percent (95%CI: 94% to 98%) did not know the Cochrane Library was an important source of systematic reviews., Conclusions: The surveyed physicians significantly over-estimated the cardiovascular risk of hypertension and the benefit of drug treatment, and had insufficient knowledge on the overall risk approach. They recommended drug treatment at a cardiovascular risk which was even much lower than the cutoff suggested for western populations, which would make many more people eligible for drug treatment. They also tended to prescribe new expensive drugs although the older cheaper ones may be more appropriate in many patients. They showed inappropriate knowledge on the basics of evidence-based medicine.

Objective: This study was undertaken to determine the relationship between red cell distribution width (RDW) and short-term outcomes in acute coronary syndrome (ACS) in a Chinese population., Methods and Patients: A total of 1,654 patients with ACS on admission were divided into four groups according to quartiles of baseline RDW. The relationships between RDW and one-month cardiac mortality as well as heart failure and recurrent infarction were assessed., Results: Higher RDW values were associated with increased one-month cardiac mortality (quartile 1: 0.2%; quartile 2: 0.6%; quartile 3: 3.3%; quartile 4: 8.1%; p<0.001) and one-month heart failure and recurrent infarction (quartile 1: 2.1%; quartile 2: 2.7%; quartile 3: 3.6%; quartile 4: 15.2%; p<0.001). Logistic regression analysis revealed that RDW independently predicted for cardiac mortality (OR: 2.116, 95% CI: 1.427-3.137, p<0.001) and heart failure and recurrent infarction (OR: 2.134, 95% CI: 1.602-2.844, p<0.001) during a one-month follow-up in patients with ACS., Conclusion: The present study indicates that elevated RDW could predict an increased risk of short-term adverse outcomes in patients with ACS.

Objective: To assess the iodine status of pregnant women, lactating women and babies and to understand if iodized salt as the main iodine source had met the need of people's demand in regions where iodized salt coverage rate had been over 90%, for the last five years., Methods: Pregnant and lactating women, newborns and babies were selected randomly in region where iodized salt coverage rate had been more than 90%, for the five years. Urine iodine levels of pregnant and lactating women, newborns and babies, milk iodine of lactating women and thyroid-stimulating hormone (TSH) of newborns were measured., Results: The median urinary iodine (MUI) of people other than those recently pregnant women, had reached the MUI criterion recommended by WHO with the results as 174.18, 180.37, 147.42, 126.27, 145.26 microg/L, respectively. The percentage of TSH>5 pIU/ml of newborns was 14.5%. The median milk iodine of lactating women were in the range of 100-200 microg/L. The percentage of milk iodine < 150 microg/L of early lactating women was less than that of late lactating women (P < 0.01). There was a good correlation between urine iodine of babies and milk iodine of lactating women. The abnormal TSH of women was 15.4%. The abnormal TSH mainly existed in women whose urinary iodine level were lower than 150 microg/L., Conclusion: Iodized salt as the main iodine source could basically meet the need of pregnant women, lactating women and babies whose diet structure was simple in the region. However, some people in the area were still under the status of iodine deficiency suggesting that surveillance should be enhanced in people who need more iodine and efficient measures, should be taken.