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1.
ACS Omega ; 9(18): 20012-20020, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38737061

RESUMO

In the process of coalbed methane extraction, due to the strong hydrophilicity of coal, the surface interaction force between water and the coal matrix is strong. The hydrophobic effect of the coal seam during drainage and pressure reduction is not significant, and adsorbed methane is difficult to desorb. In order to reduce the surface interaction force promoting methane desorption between water and coal, the surfactants NH766, G526, and D001 with a concentration of 0.1% were selected. A pressure of 12 MPa, which is close to that used for the on-site mining of coalbed methane in Baode, was selected as the experimental condition to simulate hydraulic fracturing of high fat coal, and the influence of different surfactants on methane desorption characteristics was analyzed. Combining contact angle experiments and infrared spectroscopy experiments, we explored the changes in wettability of the coal samples. We compared the changes in wettability and methane desorption characteristics and explored the similarities between these changes. The experimental results showed that after NH766 treatment, the content of oxygen-containing functional groups in coal rock decreased by 30%, and the contact angle of the coal matrix surface increased by 10°. Furthermore, its hydrophobicity was enhanced, and the desorption amount increased by 24%. In contrast, the oxygen-containing functional groups in coal rock after G526 and D001 treatments increased by 5% and 16%, respectively, and the contact angle of the coal matrix surface became smaller. Furthermore, its hydrophilicity was enhanced, and the desorption amount was reduced by 12.5% and 20%, respectively. NH766 reduces wettability and promotes methane desorption, and it can be applied to improve CBM extraction efficiency. G526 and D001 enhance wettability and inhibit methane desorption, which make them suitable for dust prevention and gas control in coal mines.

2.
Front Public Health ; 12: 1295924, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38327571

RESUMO

Purpose: Recent studies have shown that physical activity (PA) levels are low among children and adolescents globally. In order to reverse this trend, PA interventions are increasingly favoured. The school setting is the ideal place to address the issues that many children face. The purpose of this study was to (a) The primary focus of this study is to delve into the mediating role played by school-based rope skipping sports participation (SRSP) in the connection between social support and moderate to high-intensity physical activity (MVPA) among school children. (b) Additionally, this research aims to examine the moderating effect of within this pathway. Methods: We conducted a survey involving 721 adolescents residing in Changsha City. The participants' ages ranged from 8 to 12 years, with an average age of 9.84 ± 1.535 years. Out of these participants, 406 were boys, and 315 were girls. To assess variables such as social support and autonomous motivation, we employed standardized measurement scales. Subsequently, we analyzed the collected data using various statistical methods, including independent s-amples t-tests, bivariate correlation analysis, descriptive statistical analysis, structural equation modeling (SEM), and the Johnson-Neyman method. Results: An independent samples t-test revealed a statistically significant difference in MVPA between genders (p = 0.003 < 0.05), with boys exhibiting a higher level of engagement in MVPA compared to girls, Correlation analysis revealed significant positive associations among several key variables. Specifically, social support demonstrated a noteworthy positive correlation with autonomous motivation (r = 0.331, p < 0.01) as well as school children's engagement in MVPA (r = 0.308, p < 0.01). Moreover, autonomous motivation displayed a significant positive correlation with school children's involvement in MVPA (r = 0.459, p < 0.01). The moderating analysis revealed a significant influence of the interaction between increased participation in and social support on school children's engagement in MVPA. Conclusion: Social support and autonomy support have been proven effective in enhancing school children's engagement in MVPA. They exert their influence indirectly by fostering autonomous motivation. Notably, robust social support can significantly benefit MVPA school children with high activity requirements, particularly those regularly engaged in MVPA during the school day.


Assuntos
Motivação , Esportes , Criança , Adolescente , Humanos , Masculino , Feminino , Comportamento Infantil , Exercício Físico , Apoio Social
3.
Front Psychol ; 14: 1220362, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37854135

RESUMO

Introduction: This study explores the relationship between perceived school climate and exercise behavior among obese adolescents, as well as the multiple mediating effects of perseverance qualities and exercise benefits. Methods: A survey was conducted on 586 obese adolescents in Beijing, with an age range of 13-18 years old and an average age of 15.40 ± 1.824, among who 337 were male, 249 were female, 303 were high school students and 238 were middle school students. A standard scale was used to evaluate perceived school climate, exercise benefits, perseverance qualities, and exercise behaviors. The data was analyzed by independent samples t-test, bivariate correlation analysis, descriptive statistical analysis, and structural equation model (SEM). Results: (1) Perceived school climate among obese adolescents positively predicted exercise behavior (Z = 2.870, p < 0.01), perseverance qualities (Z = 3.107, p < 0.01) and exercise benefits (Z = 4.290, p < 0.001); perseverance qualities positively predicted exercise behavior in obese adolescents (Z = 4.431, p < 0.001); exercise benefits positively predicted the obese adolescents' exercise behavior (Z = 4.267, p < 0.001). (2) Perseverance qualities (Z = 2.282, 95% CI [0.032, 0.191], [0.028, 0.179]) and exercise benefits (Z = 2.518, 95% CI [0.060, 0.287], [0.053, 0.271]) play a mediating role in the obese adolescents' perceived school climate and exercise behavior, respectively. These two factors have parallel multiple mediating effects between obese adolescents' perceived school climate and exercise behavior, with mediating effects accounting for 16 and 25%, respectively. The mediating effect of exercise benefits is greater than that of perseverance qualities. (3) There is no difference in the specific indirect effects of perseverance qualities and exercise benefits (Z = -0.800, 95% CI [- 0.198, 0.064], [-0.190, 0.068]). Conclusion: Obese adolescents' perception of school climate can effectively enhance their motivation to participate in exercise behavior and indirectly influence exercise behavior through exercise benefits and perseverance qualities, cultivate good physical exercise behavior among obese adolescents, and effectively prevent and intervene in the occurrence of obesity.

4.
Front Public Health ; 11: 1133614, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37521969

RESUMO

Metabolic syndrome (MetS) has the largest global burden of all noncommunicable diseases. Owing to the clinical heterogeneity of MetS, wide variations have been reported in the efficacy of moderate-to-vigorous physical activity (MVPA) and intermittent fasting (IF) for improving MetS. We searched five databases for randomized controlled trials published through December 2021, and 372 participants from 11 studies were included in this meta-analysis. Compared with MVPA alone, IF combined with MVPA had a more significant effect on improving body mass and levels of fasting blood glucose and high-density lipoprotein cholesterol; however, it was ineffective in improving triglycerides level, systolic blood pressure, and diastolic blood pressure. Subgroup analysis showed that, except for blood pressure, time-restricted fasting combined with MVPA had a better effect than alternate-day fasting with MVPA. Meanwhile, when the intervention lasted longer than 8 weeks, the effect of the combined intervention was significantly better than that of MVPA alone. This finding provides a basis for clinicians to manage the health of overweight individuals. This study also showed that Caucasians may be more suitable for the combined intervention than Asians. And the combined intervention may provide a preventive effect for MetS risk factors in healthy populations, although this may be due to the small sample size. In general, this study provides a novel perspective on special interventions for MetS traits.

5.
Front Nutr ; 10: 1062845, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37360293

RESUMO

Background: Chinese college students used to eat in student canteens, making dietary consumption outside the cafeterias the main reason for the difference in sodium intake. This study aims to develop and validate a food frequency questionnaire (Sodium-FFQ) targeting dietary sodium intake outside the canteens among undergraduates in China. Methods: This cross-sectional study included 124 and 81 college students from comprehensive universities in the development and validation stage. A 24 h dietary recall and a food frequency questionnaire were used to develop the Sodium-FFQ. Food items were selected according to the foods that contributed more to the total sodium intake. Test-retest correlation coefficients with an interval of 14 days were employed to evaluate reproducibility. Validity was assessed against a single 24 h urine collection and a 3-day dietary record using correlation coefficients, Bland-Altman analyses, and cross-classification analysis of Kappa coefficients. Results: The Sodium-FFQ consists of 12 groups of foods with 48 items. The Spearman correlation coefficient of test-retest on sodium intake was 0.654 (p < 0.05), and that between the Sodium-FFQ, 3 × 24 h dietary record, and 24-h urinary sodium were 0.393 (p < 0.05) and 0.342 (p < 0.05), respectively. The Sodium-FFQ was correlated to 24 h urinary sodium-to-potassium ratio, with a Spearman coefficient of 0.370 (p < 0.05). The classification agreement of the Sodium-FFQ and 24 h urinary sodium was 68.4%, and the Kappa coefficient was 0.371 (p < 0.001). Conclusion: The Sodium-FFQ developed in this study presented an acceptable reproducibility, validity, and classification agreement. It indicates that the Sodium-FFQ could be a potential tool for promoting sodium restriction in college students.

6.
Artigo em Inglês | MEDLINE | ID: mdl-36901042

RESUMO

On the basis of self-efficacy theory, self-control theory and psychological resilience theory, this paper discusses the relationship between physical exercise, self-efficacy, self-control, psychological resilience and Internet addiction among adolescents in Beijing. A convenience sampling method was used to conduct a questionnaire survey on physical activity and Internet addiction among 466 adolescents from first to third year in 10 high schools in Beijing, of which 41% were girls and 59% were boys; 1.9% of students were 14 years old, 42.5% were 15 years old, 23.4% were 16 years old, 31.3% were 17 years old and 0.9% were 18 years old. Using the research methods of the literature, correlation analysis and multiple intermediary structure model, this paper constructed and tested the multiple intermediary model between physical exercise and Internet addiction. The results show that physical exercise can significantly predict self-efficacy, psychological resilience and self-control; self-efficacy, psychological resilience and self-control significantly interfered with Internet addiction behaviour; there was a significant difference in the total effect of multiple intermediaries; the effect value was -0.173; the specific indirect effects of self-efficacy, psychological resilience and self-control had intermediary effects in the relationship between physical exercise and Internet addiction; and there was no difference in specific indirect effects. This paper puts forward some countermeasures and suggestions to prevent teenagers' Internet addiction from cultivating, such as through good sports activities, thereby improving their Internet addiction. We should actively strive to improve teenagers' deep understanding of the effect of physical exercise and gradually form physical exercise habits, with sports addiction replacing Internet addiction.


Assuntos
Comportamento Aditivo , Transtorno de Adição à Internet , Masculino , Feminino , Humanos , Adolescente , Exercício Físico , Instituições Acadêmicas , Autoeficácia , Pequim , Comportamento Aditivo/psicologia , Internet
7.
ACS Omega ; 8(7): 6584-6596, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36844577

RESUMO

The geological conditions of coal reservoirs in China are complex, and the reservoir permeability is generally lower. Multifracturing is an effective method of improving reservoir permeability and coalbed methane (CBM) production. In this study, two types of dynamic loads, CO2 blasting and a pulse fracturing gun (PF-GUN), were used to conduct multifracturing engineering tests in nine surface CBM wells in the Lu'an mining area in the central and eastern parts of the Qinshui Basin. The curves of pressure versus time of the two dynamic loads were obtained in the laboratory. The prepeak pressurization time of the PF-GUN was 200 ms, and that of the CO2 blasting was 2.05 ms, which just falls in the optimum pressurization time of multifracturing. The microseismic monitoring results revealed that, in terms of the fracture morphology, both the CO2 blasting and PF-GUN loads produced multiple sets of fractures in the near-well zone. In the six wells used for the CO2 blasting tests, an average of three branch fractures were produced outside of the main fracture, and the average angle between the main fracture and the branch fractures exceeded 60°. In the three wells stimulated by PF-GUN, an average of two branch fractures were produced outside of the main fracture, and the average angle between the main fracture and the branch fractures was 25-35°. The multifracture characteristics of the fractures formed via CO2 blasting were more obvious. However, a coal seam is a multifracture reservoir with a large filtration coefficient; the fracture will not extend after reaching the maximum scale under a certain gas displacement condition. Compared with the traditional hydraulic fracturing technique, the nine wells used in the multifracturing tests exhibited an obvious stimulation effect with an average increase of 51.4% in daily production. The results of this study provide an important technical reference for the efficient development of CBM in low- and ultralow-permeability reservoirs.

8.
Med Eng Phys ; 111: 103943, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36609015

RESUMO

The design of the probes is based on bioluminescence imaging, which has been widely adopted in studies of many important biological processes. Traditional Chinese Medicine (TCM) fitness could improve the state of health of adults' intestinal flora. The research aims at analyzing the impact of TCM fitness on the intestinal probiotics (Bifidobacterium, Lactobacillus) and opportunistic pathogen (Enterococcus, Enterobacteriaceae) by the noninvasive imaging. In accordance with the searching results, the researchers have found that TCM fitness has a significant impact on improving Bifidobacterium (SDM = 1.55; P = 0.02) and Lactobacillus (SDM = 1.26; P <0.01), while the impact could not be seen on Enterococcus (SDM = 0.29;P = 0.68) and Enterobacteriaceae (SDM = 0.05;P = 0.94). And there is no significant difference between the two interventions of Tai Chi and Fitness Qigong. The results of the present review show that TCM fitness could significantly better the probiotics of intestinal flora while the influence on opportunistic pathogen needs to be further investigated with the precise and reasonable proof of scientific studies.The findings suggest that TCM fitness can be used as an effective intervention, and there is no significant difference between the two interventions on the improvement of the intestinal flora. The using of optical tool based on ultrasensitive bioluminescent imaging may lead to better precision medicine treatments in the future.


Assuntos
Microbioma Gastrointestinal , Qigong , Tai Chi Chuan , Medicina Tradicional Chinesa/métodos
9.
Artigo em Inglês | MEDLINE | ID: mdl-36360973

RESUMO

Inadequate intake of fruits and vegetables (FV) and moderate-to-vigorous physical activity (MVPA) in children has become a global public health problem. Therefore, school-based gardening and cooking (SGC) and sports participation (SP) interventions may be effective in improving children's FV intake and MVPA. The aim of this study is to develop and evaluate the effectiveness of SGC and SP interventions on FV intake and MVPA among Chinese children. In this cluster randomized controlled trial study, 237 children in grades 4-5 from six public primary schools from Changsha, Hunan Province, China will be randomly assigned to: (1) a SGC and SP combined intervention group; (2) a SP intervention group; (3) a regular practice group. The intervention clusters will be implemented for a period of 6 months and follow up will be carried out after 12 months. The outcome will be collected using a combination of self-reported and objective measures. Primary outcomes will include children's FV intake and duration of MVPA per day, and secondary outcomes will included frequency and attitudes of FV intake and SP, in addition to other measures. Finally, a process evaluation will be used to analyze the facilitators and barriers to intervention implementation. Trial Registration: (Registration Number: ChiCTR2200064141).


Assuntos
Jardinagem , Verduras , Criança , Humanos , Frutas , Promoção da Saúde/métodos , Instituições Acadêmicas , Culinária , Exercício Físico , Serviços de Saúde Escolar , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Comput Math Methods Med ; 2022: 4700325, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36060664

RESUMO

Purpose: The study is conducted to analyze the risk factors and the protective factors of myopia in Chinese adolescents and its correlation with physical activities and then to provide 2 formulas to predict the probability of becoming myopic and the probability of preventing myopia. Methods: This is a cross-sectional study in which a questionnaire survey was conducted among 650 students aged 14-17 from 5 schools in Beijing in 2021. The students were divided into two groups: nonmyopia group and myopia group. Statistically significant variables were selected after the univariate analysis for a binary logistic regression analysis. Results: In the univariate analysis, 18 risk factors of myopia were found and 14 physical-activity-related protective factors were found. In the multivariate analysis, 5 independent factors were found to be positively related to myopia and could be used for calculating the probability of becoming myopic. The 5 factors are gender, staying up late playing smartphones, parental myopia, daily time spent on digital devices, and regular eye examinations. Five physical-activity-related factors were found to be positively related to the prevention of myopia and can be used for the calculation of the probability of preventing myopia. The 5 factors are regular physical activities, attitude towards physical education, daily time spent on in-school physical activities, daily time spent on after-school physical activities, and eye exercises. Conclusions: The influencing factors of myopia in adolescents mainly include heredity, habits of using eyes, and environment. Physical activities can effectively reduce the probability of becoming myopic in adolescents and promote eye health. Therefore, taking part in physical activities is an effective way to reduce the prevalence of myopia in adolescents.


Assuntos
Miopia , Adolescente , China/epidemiologia , Estudos Transversais , Exercício Físico , Humanos , Miopia/epidemiologia , Miopia/prevenção & controle , Estudantes
11.
Biomed Res Int ; 2022: 6879566, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35342756

RESUMO

Objective: This study is aimed at evaluating the effect of Chinese traditional Wushu (CTW) on cancer-related fatigue (CRF), sleep quality, and upper limb dysfunction. Data Sources. We searched studies containing randomized controlled trials up to July 2021 in PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang database, and China Biological Medicine on this topic. Methods: A randomized controlled trial of CTW on major outcome indicators such as CRF, sleep quality, and upper limb dysfunction of breast cancer survivors. Study screening, data extraction, and risk of bias assessment were performed independently by two reviewers. Meta-analysis was conducted with Stata 16.0 software. The quality of the evidence was assessed by the Cochrane Collaboration Risk of Bias (ROB2.0). Results: Eighteen studies met the requirements for meta-analysis (n = 1331). We found that CTW has no obvious effect on improving breast cancer survivors' CRF (SMD = -0.733; P = 0.059; I 2 = 89.3%), but it can effectively improve their sleep quality (WMD = -2.266; P = 0.022; I 2 = 99.2%) and upper limb dysfunction (SMD = 1.262; P ≤ 0.001; I 2 = 88.5%). Conclusion: Although more studies on this topic are needed to prove the effectiveness of this method, the results of our review show that CTW is significantly helpful for better sleep and upper limb dysfunction. But the effects on CRF will need to be confirmed further. Implications for Cancer Survivors. In the future intervention process, to verify the effectiveness of CTW on improving CRF for breast cancer survivors, it would be suggested to pay close attention to breast cancer survivors' response to exercise, achieve regular follow-up, strictly conduct the intervention scheme on the premise of ensuring absolute security, and reduce the loss of intervention objects.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Artes Marciais , Neoplasias da Mama/complicações , Fadiga , Feminino , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Qualidade do Sono , Extremidade Superior
12.
Nutrients ; 13(8)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34444765

RESUMO

School gardening activities (SGA) combined with physical activities (PA) may improve childhood dietary intake and prevent overweight and obesity. This study aims to evaluate the effect of SGA combined with PA on children's dietary intake and anthropometric outcomes. We searched studies containing randomized controlled trials up to January 2021 in Web of Science, PubMed, Cochrane Library, and the EBSCO database on this topic for children aged 7 to 12 years. Fourteen studies met the requirements for meta-analysis (n = 9187). We found that SGA has no obvious effect on improving children's BMI (WMD = -0.49; p = 0.085; I2 = 86.3%), BMI z-score (WMD = -0.12; p = 0.235; I2 = 63.0%), and WC (WMD = -0.98; p = 0.05; I2 = 72.9%). SGA can effectively improve children's FVs (WMD = 0.59, p = 0.003, I2 = 95.3%). SGA combined with PA can significantly increase children's FVs but cannot greatly improve weight status. Although more studies on this topic are needed to prove the effectiveness of this method, the results of our review show that both SGA and SGA combined with PA has a modest but positive impact of reducing BMI and WC outcomes but can significantly increase children's FVs.


Assuntos
Exercício Físico , Jardinagem , Obesidade Infantil/terapia , Instituições Acadêmicas , Criança , Bases de Dados Factuais , Ingestão de Alimentos , Humanos , Sobrepeso
13.
Sci Total Environ ; 712: 136371, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-31931196

RESUMO

Considering that Canada joined and then withdrew from the Kyoto Protocol, we assess the impact of the dynamics of Canada's environmental policy on the general innovation and environmental innovation of oil and gas firms. This study compensates for the shortcomings of the Porter hypothesis, which features no discussion of the influence of a loosened environmental policy on innovation. We highlight that the quantity and quality of innovation can be measured using the numbers of patents and citations of patents as proxy variables. We find that the dynamics of Canada's environmental policy have an asymmetric impact on oil and gas firms' innovation; strict policy promotes firm innovation and loose regulation reduces firm innovation, with the positive effect of strict policy being stronger than the negative effect of loose policy. In addition, environmental policy has a strong impact on environmental innovation. A loosened environmental policy increases the number of environmental patents but reduces the number of citations of environmental patents.

14.
Chinese Journal of School Health ; (12): 1544-1546, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-829324

RESUMO

Objective@#To understand the differences in physical indices, physical functions, and physical fitness among primary school students of De’ang and Han nationalities in the De’ang community, and to provide a reference for the healthy development of the physique of children and adolescents.@*Methods@#The cluster sampling method was used to select the test data of height, weight, vital capacity, 50 meter running, seated forward flexion, and 1 minute skipping rope of 2 493 De’ang and Han pupils in five complete primary schools in Mangshi, Dehong Prefecture. Differences in each indices were compared between groups.@*Results@#For physical indicators: height in boys in 8,9 and 11 year old group, girls in 7 and 8 year old group, were significantly higher in Han nationality,weight among Han boys of 9 years old was higher than Deang nationality; For physical function indicators: vital capacity of girls 11 years old group and 12 years old group, boys 9 years old group, 10 years old group, 12 years old group, children of Han nationality were higher than Deang peers. For physical fitness indicators: in 50 m running, Han boys of 8,9,10 and 12 year old,as well as Han girls of 8 year old were higher than age matched peers of De’ang nationality;For seated forward flexion, Han boys of 11 years old and girls of 9 years old, were lower than Deang; in 1 min skipping, Han boys of 9,10,11 and 12 year old,as well as Han girls of 9 and 10 year old, were lower than the De’ang nationality.@*Conclusion@#Unbalanced development of physical fitness is observed among primary school students of De’hong and Han nationality, with significant differences in physical, functional and fitness indices.

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