Sodium catalytic phenylpentazole cracking: a theoretical study.

This work presents an in-depth investigation into the cracking reaction mechanism of phenylpentazole (C6H5N5) under the catalytic influence of sodium metal, utilizing density functional theory. The geometries of the reactants, transition states, intermediates, and products are meticulously optimized employing the GGA/PW91/DNP level of theory. Also, a rigorous analysis is undertaken, encompassing various key factors including configuration parameters, Mulliken charges, densities of states, and reaction energies. Three distinct reaction pathways are comprehensively examined, shedding light on the intricate details and intricacies of each pathway. The results show that a remarkable outcome in which the activation energy of the C6H5N5 cracking reaction releases N2, facilitated by catalytic metal Na, reveals a strikingly reduced value of a mere 5.2 kcal mol-1 compared to the previously reported activation energies ranging from 20 to 30 kcal mol-1. Evidently, this significantly lowered barrier can be readily surpassed at typical room temperatures, exhibiting practical applicability. Notably, the alkali metal Na effectively serves as a catalyst, successfully diminishing the activation energy required for N2 production through the pyrolysis of pentazole compounds. This breakthrough discovery provides a theoretical basis for experimental research on the low-temperature cracking of pentazole compounds. It also offers valuable insights for the development and application of new high energy density materials, contributing to the creation of a green and low-carbon circular economic system.

Latent classes of health risk behaviors and their association with school connectedness among adolescents in the Wuling Mountain Area / 中国学校卫生

Objective@#To understand the potential categories of health risk behaviors among adolescents in the Wuling Mountain Area and their association with school connectedness, so as to provide reference for formulating classified and effective intervention measures.@*Methods@#From March to June 2023, 3 386 middle and high school students from eight schools in the Wuling Mountain Area were selected using the multistage stratified cluster random sampling method. A basic information questionnaire, health risk behaviors questionnaire, and school connectedness scale were utilized for the survey. The latent classes of adolescent health risk behaviors in the Wuling Mountain Area were investigated by using latent class analysis, while an multinomial Logistic regression model was employed to analyze the association between latent classes and school connectedness.@*Results@#Adolescent health risk behaviors in the Wuling Mountains Area were classified into three latent classes: high risk class of episodic behaviors ( 5.64 %), high risk class of implicit behaviors (26.90%), and low risk class of implicit behaviors (67.45%). Gender, ethnicity, and family type revealed significant differences in the distribution of the three latent classes ( χ 2=117.91, 22.55, 21.51, P <0.05). The results of the regression model analysis showed that, with the low risk class as the reference category, high school connectedness scores were associated with the high risk class of episodic behaviors ( OR=0.89, 95%CI = 0.88- 0.91) and the high risk class of implicit behaviors ( OR=0.90, 95%CI =0.89-0.91)( P <0.05).@*Conclusions@#The characteristics of adolescent health risk behavior classes in the Wuling Mountain Area are obvious. The high risk class of episodic behaviors and the high risk class of implicit behaviors are negatively correlated with school connectedness. Corresponding measures should be taken to enhance adolescents sense of belonging in school and reduce the aggregation and co occurrence of health risk behaviors.

Three decades of shade trees improve soil organic carbon pools but not methane uptake in coffee systems.

The rapid expansion of coffee plantations in tropical area at the cost of natural forest may suppress the methane (CH4) uptake and change the soil fertility. However, observations on soil CH4 uptake rates and the ecological consequence studies on coffee-based plantations are sparse. The objectives of this study were to characterize the dynamics of CH4 uptake among natural forest, coffee monoculture (CM), and coffee intercropping with shade tree (CI), and to evaluate the key drivers of soil CH4 uptake. Results showed that the conversion of forest into 25-year and 34-year CM plantations significantly reduced the soil organic carbon (SOC) content by 57% and 76%, respectively, whereas CI plantation profoundly increased the SOC by 20%-76% compared with CM plantation. Although soils of forest, CM and CI functioned exclusively as CH4 sinks, the CM and CI plantations significantly decreased the ambient CH4 uptake rates by 64%-83% due to soil moisture shift and soil nitrate availability by using chemical fertilizer. Interestingly, the potential CH4 uptake of CM and CI plantations did not decrease and in some treatments, was even higher than that of the natural forest. Potential CH4 uptake showed a negative correlation with soil pH and SOC content, but a positive correlation with soil available phosphorus (AP). Collectively, although the SOC and soil pH were increased through intercropping with shade trees for decades, the inhibition of atmospheric CH4 uptake was still difficult to alleviate.

[Effects of exercise on bone mineral content in children and adolescents at different growth stages: a Meta-analysis].

OBJECTIVE: To evaluate the effect of exercise on bone mineral content(BMC) in children and adolescents at different growth stages. METHODS: EMBASE, PubMed, Web of Science, CNKI, VIP database and Wanfang database were searched. The randomized controlled trials(RCTS) published in Chinese and English on the effects of exercise on BMC in children and adolescents were collected using exercise, children, adolescents and BMC as search terms. Cochrane collaboration tool was used to evaluate the quality of the included studies, and RevMan5.4 software was used for Meta-analysis. The search time limit is from the establishment of the database to July 20, 2022. RESULTS: A total of 18 articles(22 RCTS) involving 1305 children and adolescents were included. The result of the Meta-analysis showed that: Compared with the control group, (1) exercise significantly improved spinal BMC(SMD=0.28, 95%CI 0.17-0.40, P<0.01) and femoral neck BMC(SMD=0.40, 95%CI 0.20-0.61, P<0.01), but not for systemic BMC(SMD=0.08, 95%CI-0.04-0.21, P=0.19). (2) Subgroup analysis showed that exercise significantly improved spinal BMC in the following stages: prepubertal(SMD=0.48, 95%CI 0.27-0.69, P<0.01)and early pubertal(SMD=0.22, 95%CI 0.05-0.39, P=0.01). The stages in which exercise significantly improved femoral neck BMC were as follows: prepubertal(SMD=0.60, 95%CI 0.05-1.16, P=0.03), early pubertal(SMD=0.22, 95%CI 0.01-0.43, P=0.04), middle and late pubertal(SMD=0.43, 95%CI 0.13-0.72, P<0.01). CONCLUSION: Exercise significantly enhanced spinal BMC during preadolescence and early adolescence as well as femoral neck BMC throughout childhood and adolescence, especially with higher effect sizes during preadolescence.

Potential categories of health risk behaviors of college students in Wuling Mountain Area and its association with campus bullying / 中国学校卫生

Objective@#To understand the potential categories of harmful behaviors of college students in Wuling Mountain Area and its relationship with campus bullying, so as to provide a theoretical basis for promoting the development of college students physical and mental health.@*Methods@#The stratified random cluster sampling method was used to select 3 042 college students from six universities in Wuling Mountain Area from October to December, 2022. The "Chinese Youth Health Related/Risk Behaviors Questionnaire" (University Edition) compiled by the National Youth Health Related/Risk Behaviors Survey Group was used to investigate the health risk behaviors. The potential category analysis method was used to analyze the food preference, insecurity, fighting, loneliness, depression, insomnia, heartbreak, suicidal ideation, smoking, drinking, game addiction, Internet addiction of health risk behaviors were used to further analyze the relationship between different categories and campus bullying by using multi category Logistic regression method.@*Results@#College students in Wuling Mountain Area were classified into low risk group of category 1 (44.2%), category 2 (5.4%) substance dependent group, category 3(50.4%) emotional disorder group. The distribution of potential categories of health risk behaviors among college students was statistically significant by gender( χ 2=31.44, 11.69， P < 0.05 ). Logistic regression analysis showed that after controlling demographic variables, campus bullying was the risk factor of category 3 emotional disorder group( OR =1.88, P <0.01).@*Conclusion@#bullying. Colleges and universities should attach great importance to the occurrence of campus bullying, formulate intervention programs for different categories of health hazard behaviors, and promote the healthy development of college students physical and mental health.

Effect of Vitapex Combined with AH-Plus Paste on Inflammation in Middle-Aged and Elderly Patients with Periodontal-Endodontic Disease.

Aims: To investigate the effect of Vitapex combined with AH-plus paste on inflammation in middle-aged and elderly patients with periodontal-endodontic disease. Materials and Methods: A total of 80 teeth of middle-aged and elderly patients with the periodontal-endodontic disease who were treated in our hospital from June 2020 to June 2021 were selected as the research objects and were divided into comparison group and treatment group with 40 teeth each according to different treatment methods. Among them, the comparison group was filled with zinc oxide clove oil paste gutta-percha, and the treatment group was filled with Vitapex combined with AH-plus paste. The changes in apical cross-section sealing performance, periodontal pocket depth (PD), and gingival index (GI) of the two groups before treatment and after 6 months of follow-up were observed and compared, and X-ray analysis was performed. Results: There was no significant difference in the level of periodontal indexes and serum inflammatory indexes between the two groups before treatment (P > 0.05). After treatment, the levels of PD, BI, PLI, and GI in the two groups were significantly lower than before treatment (P < 0.05). The differences in IL-6, IL-10, TNF-α, and IL-1ß after treatment were significant (P < 0.05). There was no significant difference in the root canal area data of each cross-section between the two groups when the root canal was filled with root filling paste at different positions from the apex (P > 0.05). After root canal filling with root canal paste, the cross-sectional area from different parts of the root canal in the treatment group was significantly smaller than comparison group (P < 0.05). After 6 months of treatment, it was found that CEJ-BD and CEJ-AC in the treatment group were significantly lower than those in the comparison group (P < 0.05). Conclusion: Vitapex combined with AH-plus paste filling can effectively treat middle-aged and elderly periodontal-endodontic disease, which provides a certain reference for the clinical treatment of middle-aged and elderly periodontal-endodontic disease.

The use of metabolomics to reveal differences in functional substances of milk whey of dairy buffaloes raised at different altitudes.

Buffalo milk is nutrient-rich and contains less cholesterol than cow milk. Dairy buffaloes are widely distributed at different altitudes in the Yunnan Province, China; however, the impacts of altitude on the whey-derived functional metabolites of buffalo milk whey are not well understood. Here, we used non-targeted and targeted metabolomics to evaluate the differential metabolites in the milk whey of buffaloes raised at low altitudes (LA), medium altitudes (MA), and high altitudes (HA). ANOVA statistical test was performed to acquire differential metabolites using IBM SPSS statistics 22 software. The results showed that LA- and MA-milk whey had higher levels of amino acids (glutamine and pyroglutamic acid) and vitamin B6 than HA-milk whey. LA-milk whey had higher levels of the carbohydrates involved in galactose, amino sugar, and nucleotide sugar metabolism than MA- and HA-milk whey, but HA-milk whey showed significantly higher levels of free fatty acids. In conclusion, owing to the biological functions of their most abundant components, LA-milk is more suitable for the production of functional milk with high levels of amino acids, vitamin B6, and carbohydrates; while HA-milk is suitable as raw milk for the production of dairy products with high free fatty acid content.

DIA proteomics reveals hypotensive and immune-enhancing constituents in buffalo whey from different altitudes.

The selection of raw milk with high levels of functional components that have health-promoting activities is very important for the exploitation and production of functional milk, but the differences in the functional components of whey from buffalo raised at different altitudes have not been thoroughly investigated. Here, we detected the effects of altitudes on the functional components in whey from dairy buffalo farms situated at low altitude (LA), medium altitude (MA), and high altitude (HA) sites with data-independent acquisition proteomic approaches. In 33 samples, 9331 peptides corresponding to 1008 high-confidence proteins were detected. HA-whey had a lower level of angiotensinogen than that of the LA- and MA-whey, and conversely contained higher levels of immune-enhancing components than for the latter two groups. Differential proteins were involved in vascular smooth muscle contraction, complement and coagulation cascades, and the secretion, production and regulation pathways in immune components. LA-whey showed higher levels of lymphocyte antigen and selenoprotein F than that of the HA-whey. Owing to the biological functions of their most abundant components, HA- and LA-whey are suitable for the processing of functional milk for lowering blood pressure, and the production of immune milk, respectively.

Impacts of drainage beds covered with sand and wood shavings on the comfort behaviour of dairy buffalo in a temperate climate.

BACKGROUND: Comfortable beds play an important role in increasing the ruminant and milk production efficiency of dairy buffalo. In loose housing systems, cow lying comfort depends on both the bedding materials and bed base. RESULTS: Buffaloes spent more lying time on sand beds at depth of 15 and 20 cm (S-15 and S-20) than on beds of 10 cm (S-10a) beds or in the feed alley in Exp1 (P < 0.01). No significant difference in the cow comfort index (CCI) was detected between S-10a and S-15; however, both showed higher CCI than that of the S-20 bed. In Exp2, buffaloes spent more time lying on the wood shavings at depth of 15 cm (WS-15) bed followed by the WS-20 and S-10b beds, respectively (P < 0.01), and CCI was greater in the WS-15 bed than in the S-10b and WS-20 beds (P < 0.05). CONCLUSION: A depth of sand or wood shavings at 15 cm can meet the lying comfort requirements of dairy buffaloes when bedding materials are used above drainage beds.

Effects of surface materials of self-draining beds on cattle behavior in a temperate climate.

OBJECTIVE: The objective of the present experiment was to construct self-draining beds to keep surface bedding materials clean and dry for beef cattle comfort in a temperate climate. METHODS: In Experiment 1, a self-draining bed was covered with sand at depths of 10 cm (S-10a), 15 cm (S-15), and 20 cm (S-20) respectively. In Experiment 2, self-draining beds of different sizes were covered with 10 cm of sand (S-10b) and wood shavings (WS) at depths of 15 cm and 20 cm (WS-15 and WS-20). Fifteen cattle were engaged to evaluate the comfort of self-draining beds covered with different bedding materials. RESULTS: No cattle lay in the feed alley and cattle spent more time lying on S-10a than S-15 or S-20 in Experiment 1 (p<0.01). No difference in lying time was detected between S-15 and S-20 (p>0.05). In Experiment 2, no cattle selected the feed alley as the lying area. Cattle preferred WS-15 as the lying area and time spent lying on WS-20 was slightly higher than on S-10b (p<0.05). Feces weight was higher in the feed alley than in the different bedding areas in both Experiments 1 and 2 (p<0.01). CONCLUSION: Sand-bedding depth at 10 cm and WSs at 15 cm above the self-draining bed can provide for the lying comfort of beef cattle. Design of a special feed alley to hold most of the feces to keep bedding materials clean and dry is desirable for organic beef cattle in a loose barn.

[Characteristics of injury behaviors of the four ethnic adolescents in rural of Wuling Mountainous Area].

OBJECTIVE: To know about the characteristics of injury behaviors of the four ethnic adolescents in rural of Wuling mountainous area. METHODS: From September to October 2016, a multiple stages hierarchical cluster random sampling method was used to extract 2170 middle school students aged(15. 25±1. 70) years old from 4 rural middle schools(1011 boys, 1159 girls; 1187 junior high school students, 983 senior high school students; 537 students from the Tujia Nationality, 546 from the Miao Nationality, 523 from the Dong Nationality, and 564 from the Bai Nationality), and conducted a survey on their injuries-related behaviors by "Chinese adolescent health related behaviors questionnaire". RESULTS: The incidence rate of cycling violations, walking violations and non-safeswimming in unintentional injury behaviors of the four ethnic adolescents in rural of Wuling Mountainous Area were 29. 49%(640/2170), 3. 18%(69/2170), 29. 49%(640/2170), respectively. As to intentional injury behavior, The rates of fight, perennial insecure, suicidal idea, suicide plan, have commit suicide, enduring unpleasant mood, enduring loneliness, enduring insomnia, depression, wanting to run away from home, and having ran away from home were: 26. 36%(572/2170), 7. 60%(165/2170), 18. 85%(409/2170), 6. 54%(142/2170), 3. 27%(71/2170), 31. 06%(674/2170), 17. 05%(370/2170), 11. 84%(257/2170), 15. 85%(344/2170), 26. 22%(569/2170), 6. 87%(149/2170), respectively. The correlation analysis of injury behavior showed that cycling violations and non-safe swimming, fight, enduring loneliness, enduring insomnia, wanting to run away from home, having ran away from home were positively correlated(r=0. 051-0. 227, P<0. 05); walking violations and fight, perennial insecure, suicidal idea, enduring unpleasant mood, enduring loneliness, enduring insomnia, wanting to run away from home, having ran away from home were positively correlated(r=0. 047-0. 096, P<0. 05); non-safe swimming and fight, enduring unpleasant mood, wanting to run away from home, having ran away from home were positively correlated(r=0. 048-0. 222, P<0. 05); fight and suicidal idea, enduring insomnia, depression, wanting to run away from home, having ran away from home were positively correlated(r=0. 053-0. 164, P<0. 05); perennial insecure and suicidal idea, enduring unpleasant mood, enduring loneliness, enduring insomnia, depression, wanting to run away from home were positively correlated(r=0. 046-0. 146, P<0. 05); suicidal idea and enduring unpleasant mood, enduring loneliness, enduring insomnia, depression, wanting to run away from home, having ran away from home were positively correlated(r=0. 157-0. 342, P<0. 05); enduring unpleasant mood and enduring loneliness, enduring insomnia, depression, wanting to run away from home, having ran away from home were positively correlated(r=0. 089-0. 317, P<0. 05); enduring loneliness and enduring insomnia, depression, wanting to run away from home, having ran away from home were positively correlated(r=0. 114-0. 281, P<0. 05); enduring insomnia and depression, wanting to run away from home, having ran away from home were positively correlated(r=0. 142-0. 236, P<0. 05); depression and wanting to run away from home, having ran away from home were positively correlated(r=0. 116～0. 166, P<0. 05); wanting to run away from home and having ran away from home was positively correlated(r=0. 293, P<0. 05). CONCLUSION: There are gender, grade and ethnic differences in the occurrence of injury behavior of the four ethnic adolescents in rural of Wuling Mountainous Area, and most injury behaviors interact with each other.

School bullying and its influencing factors in higher vocational college students in western Hunan province / 中国学校卫生

Objective@#To understand current situation and influencing factors of school bullying among left-behind and non left-behind students in vocational colleges in western Hunan, and to provide reference for the prevention and control of campus bullying in vocational colleges in poverty-stricken areas.@*Methods@#A multi-stage stratified random cluster sampling method was used to select 1 241 students from higher vocational colleges in Xiangxi for questionnaire survey. The survey included basic demographic characteristics, health-related behaviors and school bullying. Associcted factors were compared among students with and without school bullying by using the χ2 test and Logistic regression.@*Results@#The reported rate of school bullying in vocational colleges was 41.82%. The reported rate of left-behind students (45.05%) was higher than that of non-left-behind students (39.21%). The difference was statistically significant (χ2=4.29,P<0.05). Multivariate unconditional Logistic regression showed that male students and good parental relationship negatively associated with school bullying among left-behind students(OR=0.55，0.47). While rural students, 5 years of senior vocational, smoking, drinking, and game addiction were positively associated with school bullying among left-behind students(OR=1.93,2.57,2.51,3.95,4.73); good relationship with mothers was associated with less school bullying(OR=0.40), while smoke, drinking and game addiction was associated with more school bullying among non left-behind students(OR=1.86,2.32，3.81)(P<0.05).@*Conclusion@#School bullying among students in higher vocational colleges in western Hunan is highly prevalent. The reporting rate among left-behind students is higher than that of non-left-behind students. Due to different factors, joint intervention measures by government, schools and families should be carried out as soon as possible.

Health risk behaviors and cluster patterns of adolescents from four minorities in rural Wuling mountainous area / 中国学校卫生

Objective@#To determine health risk behaviors and cluster patterns among adolescents from four minorities in rural of Wuling mountainous area, and to provide a reference for health education for adolescents in ethnic minority areas.@*Methods@#Totally 4 162 teenagers from 8 rural middle schools of Xiangxi Tujia and Miao Autonomous Prefecture, Dong Autonomous County of Tongdao, Huaihua, Bai Minority Village of Sangzhi County, Zhangjiajie, were selected with multi-stage stratified random cluster sampling and surveyed with a questionnaire to collect information on health risk behaviors from September to October, 2018. Cluster patterns of health risk behaviors were analyzed by sex by two-step cluster method.@*Results@#The occurrence rates of the behaviors of the adolescents from four minorities of smoking, drinking, walking violations, unsafe swimming, fighting, suicide idea, feeling lonely constantly, frequent sleeplessness, depression, internet addiction were 18.9%, 31.0%, 49.6%, 32.3%, 28.6%, 18.3%, 16.3%, 12.4%, 16.3%, 6.7% respectively, among which the highest occurrence rates were Tujia teenagers’ fight(31.4%), Miao teenagers’ unsafe swimming(45.1%), Dong teenagers’ drinking(34.8%), Bai teenagers’ walking violation(52.9%). And the differences were statistically significant(P<0.05). Among the lowest risk group, there were 322 male students (16.4%) and 496 female students (22.5%); Among the moderate low group, there were 377 male students (19.3%) and 536 female students (24.3%); Among the implicit behavior high risk group, there were 518 male students (26.5%) and 758 female students(34.4%);Among the explicit behavior high risk group, there were 741 male students (37.8%) and 414 female students(18.8%). 23.1% of teenagers engaged in four or more types of health risk behaviors, with male higher than that of female(χ2=183.52, P<0.01), and the rate of Miao teenagers (28.2%) was the highest.@*Conclusion@#Health risk behaviors among minority adolescents in Wuling rural areas are prevalent and varied in ethnicity. Clustering of explicit risk behaviors in boys and implicit risk behaviors in girls were obvious. The hierarchical guidance and comprehensive intervention should be carried out on the basis of the characteristics of different minority teenagers’ health risk behaviors.

[Analysis on prevalence and influencing factors of health risk behaviors of Dong and Bai Nationality adolescents in rural of Wuling mountainous area in 2016].

OBJECTIVE: To understand the health risk behaviors prevalence and influencing factors of Dong and Bai Nationality adolescents in rural of Wuling mountainous area. METHODS: By the method of layered, random and total sampling, 2176 Dong and Bai Nationality adolescents were recruited from September to Octomber 2016 in rural of Wuling mountainous area. The investigation was conducted based on " The scale and evaluation method of health related/risk behaviors for adolescents in China". To analyze the behaviors on dietary bias, lack of physical exercise, suicidal ideation, smoking, drinking and internet addiction. Non conditional Logistic regression analysis was used to analyze the possible influencing factors of health risk behaviors. RESULTS: The report rates of dietary bias, lack of physical exercise, suicidal ideation、smoking、drinking and internet addiction were 36. 95%( 804), 55. 15%( 1200), 19. 03%( 414), 13. 60%( 296), 30. 88%( 672)and 7. 12%( 155), respectively. Logistic regression analysis result showed that the risk factors of dietary bias were schoolgirl( OR = 1. 275, P = 0. 012), lack of physical exercise( OR = 1. 751, P < 0. 001), depression( OR = 1. 297, P = 0. 046), suicidal ideation( OR= 1. 280, P = 0. 036) and internet addiction( OR = 1. 753, P = 0. 001). The risk factors of lack of physical exercise were high school( OR = 1. 839, P < 0. 001), schoolgirl( OR =1. 478, P < 0. 001), nuclear family( OR = 1. 240, P = 0. 034) and dietary bias( OR =1. 717, P < 0. 001). The risk factors of suicidal ideation were schoolgirl( OR = 1. 789, P< 0. 001), only child( OR = 1. 452, P = 0. 030), fight( OR = 1. 894, P < 0. 001), lonely( often or always OR = 4. 484, P < 0. 001), insomnia( often or always OR = 2. 392, P <0. 001), depression( OR = 2. 555, P < 0. 001) and internet addiction( OR = 1. 766, P =0. 004), the protective factor was in residence( OR = 0. 755, P = 0. 029). The risk factors of smoking were in residence( OR = 1. 638, P = 0. 004), fight( OR = 2. 315, P < 0. 001), insomnia( often or always OR = 2. 116, P = 0. 004) and drinking( OR = 5. 456, P < 0. 001), the protective factor were schoolgirl( OR = 0. 132, P < 0. 001) and school record( above average or good OR = 0. 571, P = 0. 004). The risk factors of drinking were total monthly income of family( above 3000 yuan OR = 1. 648, P = 0. 015), fight( OR = 1. 990, P < 0. 001), suicidal ideation( OR = 1. 363, P = 0. 019), smoking( OR = 5. 351, P < 0. 001) and internet addiction( OR = 1. 797, P = 0. 002), the protective factor was schoolgirl( OR = 0. 459, P <0. 001). The risk factors of internet addiction were dietary bias( OR = 1. 812, P = 0. 001), suicidal ideation( OR = 1. 843, P = 0. 002), lonely( often or always OR = 3. 029, P = 0. 003), drinking( OR = 2. 028, P < 0. 001) and mainly to play games( OR = 3. 650, P < 0. 001). CONCLUSION: The Dong and Bai Nationality boys are more prone to smoking、drinking and internet addiction behaviors, while girls were likely to happen dietary bias, lack of physical exercise and suicidal ideation. Insomnia and unhealthy psychology such as lonely and depression become risk factors of multiple health risk behaviors. The combined action should be carried out in order to prevent and intervene the health risk behaviors of Dong and Bai Nationality rural adolescents.

[Current situation of neglect and its influencing factors for rural children aged 12 to 17 years old of Tujia and Miao minorities in Wuling mountainous area in 2014].

OBJECTIVE: In order to have a basic understanding of the neglect condition of rural children aged 12 to 17 years old of Tujia and Miao minorities in Wuling mountainous area as well as its causes. METHODS: According to the principle of multistage stratified cluster samplingmethod, a total of 1974 students of eight middle schoolsfrom rural areas in four counties of Tujia-Miao Autonomous Prefecture of Xiangxi had been selected from November to December in 2014( 1020 students from Tujia minority and 954 students from Miao minority). In addition, by adopting themethod of "The Normal Value of Evaluation on the Neglect of Middle School Students from 12 to 17 Years Old in Rural China", the neglect rate and degree can reflect how often and how strong children in rural areas have been neglected. Also, relative factors of the neglect was analyzed by logistic multi-factor regression analysismethod. RESULTS: The total neglect rate of children in rural areas from 12 to 17 years old of Tujia and Miao minorities was 67. 83 %( 1339/1974). The proportion of male students which was 70. 42%( 631/896) was higher than the female students counterpart, which was 65. 68%( 708/1078)( χ~2= 5. 053, P <0. 05). The total neglect degree was( 54. 96 ± 10. 31), and the degree of children between 12 and 14 years old( 55. 45 ± 9. 51) was higher than that of children between 15 and 17 years old( 54. 54 ± 10. 95)( t = 1. 980, P < 0. 05). The neglect rate and degree in medication for female students were higher than male students( χ~2= 10. 233, P < 0. 01, t =2. 139, P < 0. 05), while the neglect rate and degree in education and the neglect degree in security male students had a higher rate and a more severe degree than female students( χ~2= 3. 969, t = 1. 989, t = 2. 014, P < 0. 05). In addition to the neglect of education, the neglect rate and degree of other aspects for children of Tujia and Miao minorities in rural areas had statistical significance( P < 0. 05). The neglect rate of left-behind children was higher than that of un-left-behind children in physical and medical aspects( χ~2= 6. 267, χ~2= 4. 040, P < 0. 05). As theresult of logistic multi-factor regression analysis showed, male students( OR = 1. 292, 95% CI 1. 062-1. 573), children who have less intimate relationship with parents( OR = 1. 344, 95% CI 1. 009-1. 791, OR = 1. 475, 95% CI 1. 063-2. 046), whose parents do not share a close relationship( OR = 1. 396, 95% CI 1. 042-1. 870), those without a single room( OR = 0. 577, 95% CI 0. 464-0. 719) were more likely to be neglected. CONCLUSION: Children of Tujia and Miao minorities in Wuling mountainous area are under a serious neglecting state, and the main influencing factors are whether children have single rooms, the relationship between children and parents and the relationship between parents.

[Gender differences in cluster pattern of health-risk behaviors among rural middle school students in Tujia-Miao Autonomous Prefecture of Xiangxi].

OBJECTIVE: To investigate the gender differences in cluster pattern of health risk behaviors among rural middle school students in Tujia-Miao Autonomous Prefecture of Xiangxi. METHODS: By the method of layered, random and total sampling, questionnaire survey about dietary bias, smoking, alcohol drinking, suicidal ideation, internet addiction and non-secure swimming was taken to 1974 students of eight middle schools from rural areas in four counties of Tujia-Miao Autonomous Prefecture of Xiangxi, Hunan Province in 2014. In 11 kinds of health risk behaviors as the clustering index, first by using the hierarchical clusteringmethod for male and female students were clusteranalysis, determine the optimal cluster number of male and female students were 4 class, then the two step cluster analysis, get the male and female students in 4 types of dangerous behavior clustering patterns of group characteristics. RESULTS: Among the survey of 896 boys and 1078 girls, the boys in the low risk group were composed of 262 people, the ratio was 29. 2%, the girls were composed of 215 people, the ratio was 19. 9%; the boys in the lower risk group were composed of 268 people, the ratio was 29. 9%, the girls were composed of 365 people, the ratio was 33. 9%; the boys with highest incidence of drinking in the moderate risk group were composed of 217 people, the ratio was 24. 2%, the girls with highest incidence of lonely were composed of 264 people, the ratio was24. 5%; the boys in the highest risk group were composed of 149 people, the ratio was16. 6%, the girls were composed of 234 people, the ratio was 21. 7%. In the moderate risk group, boys with highest incidence of drinking( 97. 7%) were always accompanied with behaviors like smoking( 67. 3%), fighting( 63. 6%), non-secure swimming( 66. 4%); girls with highest incidence of lonely( 45. 1%) in the moderate risk group also had behaviors like partial eclipse( 65. 2%), pedestrian violation( 50. 4%) and the like. The total boys and 92. 7% of girls have more than 4 kinds of health-risk behaviors in highest risk group. CONCLUSION: There were gender differences in risk behaviors among middle school students in rural areas of Xiangxi Autonomous Perfecture. Among them, the boys in moderate risk group were marked by drinking, the girls were marked by lonely. The highest risk group had a high rate of risky behaviors, showing a high degree of aggregation of "explicit problem behaviors and implicit behaviors".

[Analysis on prevalence and influence factors of smoking and drinking among middle shool students of Tujia and Miao in Xiangxi Area].

OBJECTIVE: To understand the prevalence and influence factors of smoking and drinking among middle shool students of Tujia and Miao in Xingxi Area. METHODS: By the method of layered, random and total sampling, questionnaire survey about smoking and alcohol drinking was taken to 2360 Tujia and Miao students. Logistic regression analysis was used to analyze the influence factors. RESULTS: The rates of try smoking and drinking were 39. 92% and 64. 87% . The rates of current smoking and drinking were 20. 04% and 26. 36%, the rates of smoking-drinking at the same was 12. 37%. The rates of start smoking and drinking before 13 years old were 30. 00% and 31. 95%. Logistic regression analysis result showed that the risk factors of current smoking were schoolboy (OR = 9. 765, P = 0. 000) and suicidal ideation (OR = 2. 139, P = 0. 000), the protective factors were city(OR = 0. 678, P = 0. 020)and school record (average OR = 0. 580, P = 0. 003,above average or good OR = 0. 477, P = 0. 002). The risk factors of current drinking were senior school (OR = 1. 438, P = 0. 005 ), Tujia (OR = 1. 784, P = 0. 000), mother' s degree of education(junior or senior school OR = 1. 330, P = 0. 045, college and above OR = 2. 938, P = 0. 000), depression (OR = 1. 570, P = 0. 004)and fight (OR = 1. 755, P =0. 000), the protective factor was school record (above average or good OR = 0. 646, P = 0. 019). The risk factors of smoking-drinking at the same were schoolboy (OR = 7. 246, P = 0. 000), left-behind children (OR = 1. 412, P = 0. 023), lonely (seldom or sometimes OR = 1. 646, P = 0. 030, often or always OR = 2. 193, P = 0. 006), insomnia (often or always OR = 2. 396, P = 0. 001), depression (OR = 1. 552, P =0. 018), fight (OR = 3. 432, P = 0. 000)and suicidal ideation (OR = 1. 918, P = 0. 001),the protective factors were in dad mood (seldom or sometimes OR = 0. 362, P = 0. 000, often or always OR = 0. 386, P =0. 001) and school record (average OR =0. 587, P =0. 001, above average or good OR = 0. 354, P =0. 000). CONCLUSION: Tujia and Miao boys were more prone to smoking and smoking-drinking, the risk of smoking-drinking was significantly increased because of depression, fight and suicidal ideation, good school record was the protective factor of smoking, drinking and smoking-drinking.

Theoretical study of the correlation between electrostatic hazard and electronic structure for some typical primary explosives.

The electronic structures of lead styphnate, hexa(1,5-diaminotetrazole) cobalt perchlorate, lead azide, (5-cyanotetrazolato-N (2)) pentaammine cobalt perchlorate, and tris(carbohydrazide) zinc perchlorate were investigated via density functional theory. The results obtained reveal that the electrostatic spark sensitivities of these primary explosives are related to their electrostatic potentials and energy gaps. Highly sensitive primary explosives show large cell electrostatic potentials per unit volume and small energy gaps. Moreover, the energy levels of the frontier molecular orbitals play an important role in triboelectrification between an explosive and a flume. The lower the energy level of the lowest unoccupied molecular orbital of the primary explosive, the more easily it can accept electrons and accumulate negative charge.

[Analysis on influence factors of health risk behaviors of Tujia and Miao adolescents in Xiangxi Area].

OBJECTIVE: To understand the health risk behaviors status and influence factors of Tujia and Miao adolescents in Xiangxi Area. METHODS: By the method of layered, random and total sampling, questionnaire survey about dietary bias, current smoking, current drinking, suicidal ideation, internet addiction and lack of physical exercise was taken to 2094 Tujia and Miao adolescents. Logistic regression analysis was used to analyze the risk factors of health risk behaviors. Results The report rates of dietary bias, current smoking, current drinking, suicidal ideation, internet addiction and lack of physical exercise were 27. 84%, 18. 29%, 28. 03%, 21. 68%, 5. 25% and 52. 82%, respectively. Logistic regression analysis result showed that the risk factor of dietary bias was depression(OR = 1. 352, P =0. 026), the protective factor were schoolboy (OR =0.765, P=0.008) and in residence(OR =0.743, P =0.004). The risk factor of current smoking were schoolboy (OR =6. 782, P =0. 000), insomnia(seldom or sometimes OR = 1. 516, P = 0. 013, often or always OR = 2. 738, P = 0. 000), internet addiction (OR =2.389, P =0. 000), fight(OR = 2. 481, P = 0. 000) and current drinking(OR = 4. 060, P = 0. 000), the protective factor was school record (average OR = 0. 699, P = 0. 026, above average or good OR = 0. 437, P = 0. 000). The risk factor of current drinking were schoolboy (OR = 1. 829, P = 0. 000), insomnia (seldom or sometimes OR = 1. 550, P = 0. 002, often or always OR = 1. 754, P = 0. 004), internet addiction (OR = 1. 901, P =0. 004), fight (OR = l.785, P = 0. 000)and current smoking (OR = 4. 016, P = 0. 000). The risk factor of suicidal ideation were lonely(seldom or sometimes OR = 1. 823, P =0. 010, often or always OR = 4. 445, P =0. 000), depression (OR = 3. 226, P = 0. 000) and only child (OR = 1. 612, P = 0. 003), the protective factor was schoolboy (OR =0. 648, P = 0. 000). The risk factor of internet addiction were schoolboy (OR = 2. 480, P = 0. 000) depression (OR = 2. 650, P = 0. 000) and mainly to play games(OR = 4. 631, P = 0. 000). The risk factor of lack of physical exercise were high school student (OR = 1. 536, P =0. 000) and depression(OR = 1. 410, P = 0. 003), the protective factor were schoolboy (OR ='0. 581, P = 0. 000) and school record (average OR = 0. 798, P = 0. 036, above average or good OR = 0. 609, P = 0. 000. CONCLUSION: Tujia and Miao boys were more prone to smoking and drinking behavior, while girls were likely to happen dietary bias, suicidal ideation and lack of physical exercise behavior. Miao students were high-risk population of smoking and drinking behavior. Insomnia and depression became risk factors of multiple health risk behaviors.

[Nutritional status and related factors of Tujia and Miao minority primary school students in Xiangxi Autonomous Prefecture].

OBJECTIVE: To understand the nutritional status and related factors of Tujia and Miao minority primary school students in Xiangxi Autonomous Prefecture and to provide refrence for the improvement of minority students' nutritional status. METHODS: By the method of layered and random sampling, physique test and questionnaire survey were taken to 682 Tujia students and 420 Miao students, the nutritional level of students were estimated by the method of height with standard weight. Logistic regression analysis was used to analyze the risk factors of nutritional status. RESULTS: The moderate malnutrition rate was 4.54% and the obesity rate was 11.43%. Logistic regression analysis showed that monthly income per capita (OR = 1.368, 95% CI 1.135-1.648) and culture level of fathers (OR = 1.332, 95% CI 1.108-1.602) were independent risk factors of malnutrition, children with family obesity history (OR =7.688, 95% C15. 134-11.513), monthly income per capita (OR = 1.516, 95% CI 1.204-1.910) and culture level of fathers (OR = 1.466, 95% CI 1.164-1.846 ) were independent risk factors of overnutrition. CONCLUSION: Malnutrition and overnutrition exist in Tujia and Miao students at the same time, family obesity history, monthly income per capita and culture level of fathers are factors of malnutrition and overnutrition. Nutritional education should be taken universal to students and their guardians.