[Relationship between nutrient-related dietary pattern and mild cognitive impairment in middle-aged and elderly people in 15 provinces of China].

Objective: To explore the relationship between nutrient-related dietary pattern and mild cognitive impairment (MCI) in middle-aged and elderly people. Methods: A total of 6 444 middle-aged and elderly people aged ≥55 years were selected in 2018 China Health and Nutrition Survey. MCI was evaluated by Mini-Mental State Examination, and the intakes of various foods were obtained by consecutive 3-day 24-hour dietary survey and weighing method. The intakes of various nutrients and total dietary energy were calculated based on the food composition table. Demographic and social information, lifestyle and health status of the respondents were obtained through questionnaire survey and physical measurements. In this study, vitamin C, vitamin E, zinc, iron, copper and selenium were selected as dependent variables. Nutrient-related dietary patterns were extracted by reduced rank regression method, and the relationship between dietary patterns and MCI was analyzed by multivariate logistic regression model. Results: Six dietary patterns were extracted in this study, and dietary pattern 1 with the highest explanatory degree was selected for subsequent analysis. Dietary pattern 1 was characterized by higher intakes of legume products, vegetables, fruits, nuts, pork, aquatic products and plant oil. Multivariate logistic regression analysis showed that the risk of MCI was lower in Q4 dietary score group than in Q1 dietary score group (OR=0.69, 95%CI: 0.49-0.98) in the 55-64 age group. In people with sleep duration of 8 hours per day, the risk of MCI was reduced in Q2, Q3 and Q4 dietary score groups compared with the Q1 dietary score group, with OR values of 0.68 (95%CI: 0.51-0.92), 0.67 (95%CI: 0.49-0.92) and 0.65 (95%CI: 0.45-0.92), respectively. Interaction analysis showed that the risk for MCI increased in those aged 65-74 years and ≥75 years compared with those aged 55-64 years in Q1 dietary score group. However, the risk for MCI decreased in both age groups as dietary pattern scores increased. Compared with those with sleep duration less or more than 8 hours per day in Q1 dietary score group, those with sleep duration of 8 hours per day in Q2 and Q3 dietary score groups had a reduced risk for MCI. Conclusion: Dietary patterns with higher intakes of legume products, vegetables, fruits, nuts, pork, aquatic products, and plant oil are negatively associated with MCI in people aged 55-64 years and those who slept 8 hours per day, and may reduce the risk of MCI with aging.

[Multi-level scanning of environmental factors of body mass index of children and adolescents aged 7-17 years in China].

Objective: To investigate the influence of environmental factors on body mass index of children and adolescents in China. Methods: Using data from the China Health and Nutrition Survey, the research object to 7 - 17 years old children and adolescents who participated in 2000, 2006, 2011, and 2015 round of survey with complete data, a total of 6 626 children and adolescents (male 3 473, female 3 153) were investigated under univariate analysis for each environmental factor variable before using Partial Least Square Regression fitting a linear model for further screening. Finally, we fitted a three-level linear mixed-effects model distinct by urban and rural area for analysis. Results: The three-level null model, log likelihood=-17 034.68, χ2=483.06, P<0.001. Intern-class correlation coefficient (ICC) showed that community-level was 9.97%, and both community and individual were 39.38%. The three-level model also showed that urban model's urbanization index (ß=-0.05, 95%CI: -0.09--0.01, P<0.05), the park location (ß=-0.88, 95%CI: -1.72 - -0.04, P<0.05), 15 - 17 age group (ß=-1.04, 95%CI:-1.78 - -0.30, P<0.05) were negatively correlated with BMI. The distance to the gym (ß=0.12, 95%CI: 0.02 - 0.22, P<0.05), the number of home TV sets (ß=0.50, 95%CI: 0.08 - 0.92, P<0.05) and the frequency of parents' alarm of fiction TV program contents (ß=1.85, 95%CI: 0.70 - 3.00, P<0.05) were correlated with BMI. Rural urbanization index (ß=-0.04, 95%CI:-0.07 - -0.01, P<0.05). Rural per capita income (ß=-7.29e-4, 95%CI:-1.00e-3 - -6.77e-5, P<0.05), parents' restricted frequency of watching TV (ß=-1.29, 95%CI:-2.36 - -0.21, P<0.05), adipo-energy ratio (ß=-0.03, 95%CI:-0.06 - -1.00e-3, P<0.05) were negatively correlated with the BMI. Factors as the frequency of parents' alarm of fiction TV program contents (ß=3.01, 95%CI: 0.03 - 6.00, P<0.05), the survey time was 2015 (ß=4.83, 95%CI: 1.96 - 7.69, P<0.05) were correlated with BMI. Conclusions: Environmental factors could indirectly influence the change of BMI of children and adolescents to different degrees and various aspects. Urbanization index and rural per capita income had a slight protective effect on increasing BMI of children and adolescents. At the community level, attention should be paid to the setting of activity places around the living environment of children and adolescents. Family members should also guide their children and adolescents to develop nice behavior in watching TV.

[Dietary sodium intake of adult residents in 15 provinces of China in 2015].

Objective: To analyze the status of dietary sodium intake of Chinese adult residents in fifteen provinces in 2015. Methods: Data were collected from 2015 China Nutrition Transition Cohort Study. This cohort study used a three consecutive 24-h retrospective method to record food intake and weighing method to record household condiment consumption. In this study, 14 847 residents aged 18 years and over with complete data from 15 provinces in 2015 were selected for the comparison of dietary sodium intake (median) with different characteristics. Results: Among the 14 847 residents, 47.1% were males, and the rural and northern residents accounted for 60.1% and 37.7%, respectively. Median sodium intake was 3 960.0 mg/d among residents in 2015. The sodium intake of males (4 272.1 mg/d) was higher than that of females (3 716.6 mg/d). Across age subgroups, sodium intake was highest among residents aged 45-59 years (4 257.0 mg/d; 18-44 years old, 3 867.1 mg/d; ≥60 years old, 3 799.0 mg/d). Sodium intake was higher in rural area (4 042.9 mg/d) than in urban area (3 866.8 mg/d), higher in north (4 229.2 mg/d) than in south (3 806.8 mg/d) (all P values <0.05). 11.8% of residents with dietary sodium intake were below 2 000 mg/d. The main sources of dietary sodium were condiments (79.4%), regular cooking foods (11.9%) and processed foods (8.7%). Among the condiments, the salt and soy sauce accounted for 63.6% and 10.4%, respectively. Conclusion: In 2015, Chinese adult residents had higher dietary sodium intake with gender and regional differences. Condiments were the main source of dietary sodium.

A first-principles study of the structural, mechanical and electronic properties of precipitates of Al2Cu in Al-Cu alloys.

The properties of precipitates are important in understanding the strengthening mechanism via precipitation during heat treatment and the aging process in Al-Cu based alloys, where the formation of precipitates is sensitive to temperature and pressure. Here we report a first-principles investigation of the effect of temperature and pressure on the structural stability, elastic constants and formation free energy for precipitates of Al2Cu, as well as their mechanical properties. Based on the formation enthalpy of Guinier-Preston (GP(I)) zones, the size of the GP(I) zone is predicted to be about 1.4 nm in diameter, which is in good agreement with experimental observations. The formation enthalpies of the precipitates are all negative, suggesting that they are all thermodynamically stable. The present calculations reveal that entropy plays an important role in stabilizing θ-Al2Cu compared with θC'-Al2Cu. The formation free energies of θ''-Al3Cu, θC'-Al2Cu, θD'-Al5Cu3 and θt'-Al11Cu7 increase with temperature, while those of θ'-Al2Cu, θO'-Al2Cu and θ-Al2Cu decrease. The same trend is observed with the effect of pressure. The calculated elastic constants for the considered precipitation phases indicate that they are all mechanically stable and anisotropic, except θC'-Al2Cu. θD'-Al5Cu3 has the highest Vicker's hardness. The electronic structures are also calculated to gain insight into the bonding characteristics. The present results can help in understanding the formation of precipitates by different treatment processes.

Longitudinal association of leisure time physical activity and sedentary behaviors with body weight among Chinese adults from China Health and Nutrition Survey 2004-2011.

BACKGROUND/OBJECTIVES: Present study aims to longitudinally explore independent association of physical activity and sedentary behaviors with body weight. SUBJECTS/METHODS: This study included 15050 adults who have complete demographic and dietary data, leisure time physical activity (LTPA) and sedentary behavior evaluations, anthropometric measurements from longitudinal data of China Health and Nutrition Survey 2004-2011. Three-level mixed-effects linear and logistic regression models were performed for association analysis. RESULTS: Overweight and obesity prevalence in men and women progressively increased from 2004 to 2011. MET-h/week from LTPA declined, whereas time (h/day) spent in sedentary behaviors increased in men and women over 7 years. After adjustment for confounders, LTPA (MET-h/week) was linked with weight gain for moderate (ß=0.43, 95% confidence interval (CI): 0.16-0.60, P<0.01) and low (ß=0.52, 95% CI: 0.23-0.81, P<0.01) versus high LTPA in men; weight was increased by 0.7 kg (95% CI: 0.44-0.93, P<0.001) and 0.4 kg (95% CI: 0.12-0.68, P<0.01) among men and women without LTPA, respectively, compared with those with high LTPA. Sedentary behavior was associated with weight gain in men (ß=0.45, 95% CI: 0.14-0.76, P<0.01) and in women (ß=0.29, 95% CI: 0.11-0.49, P<0.05) for high versus low level. Moreover, overweight and obesity risk in men with low LTPA or without LTPA was 1.88 (95% CI: 1.15-2.51, P<0.05) and 2.01 (95% CI: 1.41-3.03, P<0.001) times higher than those with high LTPA, respectively. Odds of overweight and obesity were increased to 1.63 (95% CI: 1.29-2.21, P<0.01) times in women with low LTPA and 1.69 (95% CI: 1.37-2.27, P<0.001) times in women without LTPA compared with those with high LTPA. High level sedentary behavior was associated with 19% (OR=1.19, 95% CI: 1.04-1.35, P<0.05) greater odds of overweight and obesity against low level in men. CONCLUSIONS: LTPA and sedentary behaviors are independently and longitudinally associated with overweight and obesity, especially in men.

Biomechanics of the wrist after proximal row carpectomy in cadavers.

We investigated the biomechanics of the radiocapitate joint after a proximal row carpectomy in six fresh-frozen cadaver wrists using super-low-pressure-sensitive film on a material testing system. The average pressure within the lunate fossa increased significantly from 23.2 to 136.4 N/cm(2) with a sharp decrease in the contact area from 2.08 to 0.30 cm(2) after a proximal row carpectomy. The cartilage of the proximal capitate had four sub-facets and therefore was not as smooth as the normal proximal lunate. We found that the wrist was overloaded after a proximal row carpectomy and the main cause was the anatomical mismatch of the radiocapitate articulation.