With the use of Near-infrared spectroscopy(NIRS), the noninvasive measurement of cerebral oxygen concentration can be achieved in vivo based on the Lambert-Beer Law. In this paper, we discuss the possibility of studying higher brain functions through a combination of cerebral oxygen saturation and cerebral function measurement. Event-related experiments are introduced to measure the cerebral phronetal function. Time domain curves show sight differences among these experiment results. However, with the aid of DFT, experiment data of all five human volunteers show that the frequency near 20Hz or 40Hz is evoked depending on the difficulty of the mental tasks. The results demonstrate the feasibility of cerebral function studies by means of cerebral oxygen saturation measurement analysis in the frequency domain.

Objective To explore the differences of systolic segmental motion of left ventricle (LV) in patients with dilated cardiomyopathy (DCM) using illustration of the bull eye (IBE) from real-time three-dimensional echoeardiography(RT-3DE). Methods Quantitative analysis of LV segmental function was made in 43 patients with DCM by IBE. Percentage of compensated segments(PCS) was determined according to the segmental distribution by different color from IBE. Maximal exeursion(Emax),minimal excursion(Emin), average excursion (EA), standard difference of excursion(SD) and dispersion of excursion(Edis) were calculated. Results PCS in patients with DCM was 27.22%. Significant differences between DCM group and control group in Emax, Emin, EA,SD and Edis were observed( P <0. 001 ). Significant difference in segmental motion of LV was existed in patients with DCM and its distribution of motion seems tendency of irregularity. Conclnsions PCS and Edis from IBE might provide a convenient and macroscopic modality in selection of treatment and evaluation of prognosis in patients with DCM.

The biomechanical properties of 21 white New Zealand rabbits' corneas after Laser in situ keratomileusis (LASIK) were tested by use of one-dimension tensile test and creep test in the INSTRON 5544 mechanical machine. The cornea-related data from the experiments of one-dimension tensile test and creep test for an hour were obtained; a standard linear solid model was adopted to analyse the data, and the least square method was used to fit the viscoelastical coefficients of creep experiment on different corneas. We noticed there was certain difference between the LASIK groups and the normal group in respect to the corneal modulus of elasticity, the stiffness coefficients diminished with the increase of ablation depth; the anti-tensile ability of corneas also displayed some reduction. These findings indicate that the deeper the ablation goes, the easier will be the deformation after LASIK.
Animals ; Biomechanical Phenomena ; Cornea ; physiopathology ; surgery ; Elasticity ; Keratomileusis, Laser In Situ ; methods ; Lasers, Excimer ; therapeutic use ; Rabbits

Objective: To evaluate the effectiveness of a comprehensive intervention for childhood obesity on self-efficacy, weight perception, and stage of behavior change, and to provide a scientific evidence for childhood obesity interventions. Methods: The study was a cluster randomized controlled trial. Twelve primary schools and 1 889 children (aged 7-11 years) from Dongcheng District in Beijing were recruited in September, 2013, and were administered a comprehensive intervention for childhood obesity. Six schools (930) were randomly allocated to the intervention group, and six schools (959) were randomly allocated to the control group. A face-to-face questionnaire survey was carried out, R 4.0.3 software was used to analyze the data, and multiple linear regression model was used to analyze the intervention effect. Results: After the intervention, mean (standard deviation) scores of self-efficacy among children in the intervention and control groups were (4.4±0.9) and (4.2±1.1), respectively. After the intervention, the proportion of children in the intervention group who underestimated or overestimated their body weight was 28.4% and 11.3 %, respectively, while the figures in the control were 37.1% and 6.9%; compared with the control, the risk of underestimating body weight decreased among children in the intervention group( OR=0.64, 95%CI=0.52-0.80, P <0.01), while the risk of weight overestimation increased( OR=1.79, 95%CI=1.26-2.54, P <0.01). After the intervention, the proportion of children in the contemplation or action stage of behaviour change was 65.3% and 83.6%, while the figures in the control group were 59.8% and 69.8 %, respectively; in comparison with the control group, more children in the intervention group were in comtemplation ( OR= 1.28 , 95%CI=1.03-1.59, P =0.02) or action stage of behaviour change( OR=2.59, 95%CI=2.04-3.27, P <0.01). Conclusion The comprehensive intervention for childhood obesity improved self-efficacy, weight perception, and facilitated behavior change, but may increase the risk of weight overestimation.

Objective To develop a new method for describe features of inflow of left ventricle(LV) from color Doppler image by color singular value,and evaluat the value of color singular value in assessment of diastolic dysfunction. Methods Patients with diastolic dysfunction of LV including myocardial infarction (n = 37), angina( n = 35), cardiomyopathy( n = 45) and hypertension ( n =46) were selected and 30 healthy cases as control. CV and AV from color singular value of LV inflow was displayed and calculated automatically by an analyzing system developed in our laboratory. Results Compared with that of control (CV:2.40 0.22 and AV: -0.25 0.05), the absolute value of CV(1.67-1.90 in average)and AV( - 0. 11～-0. 20 in average) from color singular value were decreased significantly( P <0. 001) in groupsof myocardial infarction, angina, cardiomyopathy and hypertension. Conclusions Singular value can be applied to detect color differences in LV inflow from color Doppler signals. Changes of singular value within the diastolic inflow under pathological conditions may reflect the diastolic dysfunction of LV.

In recent years,magnetic resonance imaging (MRI) has been widely used in the early diagnosis as well as long-term follow-up study of Alzheimer's disease (AD).The studies were reviewed which applied the structural MRI and arterial spin labeling MRI (ASL-MRI) in AD over the past 20 years,and found more gray matter volume loss in multiple brain structures in individuals with AD spectrum.Among them,medial temporal lobe atrophy and posterior cortical atrophy are the most diagnostic.Meanwhile,cerebral blood flow changes in various brain regions with the progression of the AD.More investigations combining the changes of gray matter volume and cerebral blood flow to explore pathophysiological mechanisms underlying cognitive decline in AD spectrum are necessary in the future.

Objective: To study the relationship between nutrition status and physical fitness in 8-10 year-old children in 3 cities, and to provide a scientific reference for improving physical condition of chidren of pre-school age. Methods: To investigate the weight, height and physical fitness (standing long jump, endurance running, rope skipping in one minute and sit-ups in one minute) of 1 384 children in grade four from 24 primary schools in Beijing, Changzhi, Urumchi in 2018. Evaluated overweight and obesity by using the standard of “Screening for Overweight and Obesity among School-age Children”. Then used mixed linear model to compare the physical fitness of students with different nutritional status and to analyze the relationship between BMI and physical fitness. Results: The prevalence of overweight and obesity were 17.41% and 23.48%, respectively. And the prevalence in boys was both more than that in girls(χ2=9.84，47.68，P<0.01). The increase in BMI of children from the same age and the same gender was related with the decrease in physical fitness by correlation analysis(P<0.05). In comparison method, the performance of the students of normal weight was better than obese students, but the male and female students had got the same results in their physical fitness test(P<0.05). Conclusion There is a negative correlation between nutrition status and physical fitness and the physical fitness in normal weight and obese children are better than the overweight children or obese children.

Objective: To describe the baseline characteristics of School-based Cardiovascular and Bone Health Promotion Program(SCVBH) in Beijing. Methods: Children and adolescents were selected in 30 schools (8 primary schools, 21 middle schools and one 12-year education school) from Dongcheng, Tongzhou, Fangshan and Miyun districts of Beijing by using a stratified cluster sampling method. 15 391 students in grade 1 to 4 from primary schools, grade 1 from junior and senior high schools were enrolled in the investigation with an exclusion of students who were not able to participate due to trauma or other uncomfortable physical conditions. The baseline survey including a questionnaire survey, physical examination and blood biochemical test was conducted from September 2017 to January 2018. Obesity, blood pressure, fasting blood glucose, lipid, bone density and grip were evaluated. Results: The prevalence of obesity, hypertension, hyperglycemia (impaired fasting glucose and diabetes), dyslipidemia, lower bone density were 22.3%(3 394), 14.8%(2 248), 10.4%(1 490), 20.3%(2 919) and 2.1%(316) in total respectively, and 27.2%(2 081), 16.3%(1 244), 12.8%(922), 22.2%(1 595) and 1.2%(94) for boys, 17.3%(1 313), 13.3% (1 004), 7.9%(568), 18.4%(1 324) and 2.9%(229) for girls. Boys had higher prevalence of obesity, hypertension, hyperglycemia, and dyslipidemia and lower prevalence of low bone density than girls (all P values <0.05) The mean of body mass index, systolic blood pressure, fasting plasma glucose and grip of boys were significantly higher than that of girls (all P values <0.05).The mean of body mass index, systolic blood pressure, fasting plasma glucose and grip of boys were significantly higher than that of girls (all P values <0.05), the mean of fat mass percentage, total cholesterol, triglyceride, high density lipoprotein-cholesterol and low density lipoprotein-cholesterol of boys were significantly lower than those of girls (all P values <0.05). Conclusion The prevalence of risk factors of chronic cardiovascular disease was high and the low bone density was appearing in children and adolescents in this study. The promotion of cardiovascular and bone health should be implemented in children and adolescents.

Objective: To evaluate the effect of a dietary and exercise intervention on cognition and behaviors among primary school students, and to further explore the mediating role of family support, in order to provide scientific evidence for future effective intervention strategies. Methods: A dietary and exercise intervention program for childhood obesity prevention was carried out in 24 primary schools in Beijing, Changzhi and Urumqi from 2018 to 2019, and 1 392 children in grade four as well as their parents were included. Family support and children s cognition and behaviors were collected through questionnaire. To carry out diet and exercise behavior intervention on the three levels of school, family and individual in the intervention group,and children s dietary and exercise knowledge, eating habits, physical activities, as well as sedentary and screen behaviors were evaluated. The linear mixed model was used to analyze the effect of intervention on children s cognition and behaviors, and the mediation model was used to explore the role of family support. Results: The proportion of children with higher score of dietary and exercise knowledge ( OR= 2.34 , 95%CI =1.71-3.21), eating habits ( OR=2.58, 95%CI =1.75-3.82), and sedentary and screen behaviors ( OR=1.91, 95%CI =1.35-2.68) increased in the intervention group after one year intervention ( P <0.01), compared with the control group, respectively. The intervention also increased the proportion of children s family support in the intervention group compared with the control group ( OR=3.45, 95%CI =2.19-5.45), and the support from children s fathers ( OR=2.70, 95%CI =1.68-4.35), mothers ( OR=3.71, 95%CI =2.28-6.04), paternal grandmothers ( OR=1.65, 95%CI =1.00-2.70), and maternal grandmothers ( OR= 2.14, 95%CI =2.12-2.16) increased significantly ( P <0.05). The mediation analysis showed that family support played a mediating role in association between comprehensive intervention and children s eating habits as well as sedentary and screen behaviors. Conclusion The dietary and exercise intervention effectively promoted children s cognition and behaviors, and family support played an important mediating role.

Objective: To evaluate the cost effectiveness of a school based comprehensive intervention for childhood obesity and to provide scientific basis for formulating and promoting efficient and economic intervention measures for childhood obesity. Methods: In a cluster randomized controlled trial, 12 primary schools (1 889 students from grade 3 to 5) in Dongcheng District in Beijing were selected and randomly assigned to the intervention (6 schools, 930 students) and control group (6 schools, 959 students). Students in the intervention group received a one year school based comprehensive intervention for childhood obesity, including development of school level policies, health education activities, improvement of physical activity, and improvement of healthy diet. A cost analysis method from a social perspective was used to evaluate the implementation costs of the intervention. Cost effectiveness analysis was used by calculating incremental cost effectiveness ratio (ICER) on obesity related knowledge, number of days completing no less than 60 minutes of moderate to vigorous physical activity (MVPA) per week, students consuming sugar sweetened beverage. Results: The material cost and human cost were 46 376.24 yuan and 46 197.32 yuan, respectively. The total cost of the intervention was 92 573.56 yuan and the average cost was 99.54 yuan per student in the intervention group. ICER on obesity related knowledge, number of days completing no less than 60 minutes of MVPA per week, percentage of students consuming sugar sweetened beverage were 52.39%, 71.61% and 2.26%, respectively. Conclusion The school based comprehensive intervention for childhood obesity shows a good cost effectiveness promoting students obesity related knowledge, as well as dietary and physical activity behaviors.