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1.
ACS Omega ; 9(12): 14075-14083, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38559929

RESUMO

Using water to displace carbon dioxide adsorbed in coal can prevent coal and gas outbursts. However, the mechanism of continuous water injection replacing adsorbed gases in coal has not been well studied. An experiment with the same water injection pressure and different adsorption equilibrium pressures for displacing carbon dioxide was conducted. The variation patterns of the amount of displaced carbon dioxide, time, and water displacement rate, displacement ratio, and water action ratio were analyzed. The modes of water injection displacing carbon dioxide are discussed. The results show that the change in the amount of displaced carbon dioxide consists of three stages: rapid, slow, and stop growth stages. For the same displacement time, as the adsorption equilibrium pressure rises, more carbon dioxide is displaced. The time displacement rate and water displacement rate can be divided into three stages: rising, peak, and dropping stages. As the adsorption equilibrium pressure increases, the duration of the peak stage decreases, while the time and water displacement rates increase. At different adsorption equilibrium pressures, the carbon dioxide displacement ratio ranged from 45% to 54%, less than the natural desorption ratio. But the water action ratio containing the gas dissolution amount was close to or greater than the natural desorption ratio. Thus, the displacement effect of flowing water accelerated the desorption of carbon dioxide in coal. The modes of carbon dioxide displacement by water injection include water-displacement, gas-dissolution displacement, and gas-diffusion-dissolution displacement. The findings of this study provide novel suggestions for preventing and controlling coal and gas outbursts.

2.
ACS Appl Mater Interfaces ; 16(11): 14333-14344, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38449445

RESUMO

Metal-organic framework (MOF)-modified biochars (BC) have gained recognition as potent adsorbents for phosphate. However, essential insights into the electronic interfacial state of the MOFs remain lacking. In this study, we propose a novel topological transformation strategy to directionally regulate the interfacial electronic states of BC/MOFs composites. The optimized BC/MOFs exhibited an excellent selective phosphate adsorption capacity of 188.68 mg·g-1, coupled with rapid sorption kinetics of 6.81 mg·(g·min0.5)-1 in simulated P-laden wastewater. When challenged with real bioeffluent, such efficacy was still maintained (5 mg·L-1, 25.92 mg·g-1). This superior performance was due to the Fe(III) → Fe(II) transition, promoting electron mobility and leading to the anchoring of Mg(II) to form specific coordination unsaturated sites (Mg-CUS) for phosphate adsorption. Importantly, the simultaneous regulation of binary defects further enhances electron mobility, resulting in the formation of sp3 unequal hybrid orbitals with a stronger internal coupling capability between Mg 3s in Mg-CUS and O 2p in phosphate. Furthermore, the high electron affinity of Mg effectively promotes electron cycling, endowing BC/MOFs with a distinct self-healing capability to facilitate phosphate desorption. The outcomes of this study provide novel perspectives for electronic regulated phosphate adsorption.

3.
Sci Rep ; 13(1): 22407, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38104207

RESUMO

Water from hydraulic technology affects the desorption of gas from coal seams. Gas desorption behavior is critical information for gas control in coal mines. In this study, a designed coal seam water injection simulation experimental device was utilized to conduct dynamic water injection experiments on coal samples at different adsorption equilibrium pressures, analyzing the gas desorption law under dynamic water injection, as well as the role of water replacement, water imbibition and water blockage in gas desorption. The results showed that water altered the gas desorption rate in coal, causing fluctuating attenuation of the desorption rate of a water-injected coal sample (WCS). Under the same adsorption equilibrium pressure, the relationship between the desorption rate of the WCS and the non-water-injected coal samples (NCS) underwent a transition in desorption time. In contrast to the NCS desorption curves, the WCS desorption curves lacked a rapid growth phase and exhibited only a slow growth phase and a stopping phase. Water imbibition and water replacement promoted the desorption of gas in the non-wet area during the water injection process, while it inhibited the desorption of gas in the wet area. Under the effects of water imbibition, water blockage, and water replacement, the discharge rate of WCS is greater than the desorption rate of NCS, indicating that water injection increases the total amount of gas desorption. The study results have significant implications for gas extraction and the prevention and control of coal and gas outbursts.

4.
Nat Commun ; 14(1): 6733, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872207

RESUMO

The regulation of heterogeneous material properties to enhance the peroxymonosulfate (PMS) activation to degrade emerging organic pollutants remains a challenge. To solve this problem, we synthesize S-scheme heterojunction PBA/MoS2@chitosan hydrogel to achieve photoexcitation synergistic PMS activation. The constructed heterojunction photoexcited carriers undergo redox conversion with PMS through S-scheme transfer pathway driven by the directional interface electric field. Multiple synergistic pathways greatly enhance the reactive oxygen species generation, leading to a significant increase in doxycycline degradation rate. Meanwhile, the 3D polymer chain spatial structure of chitosan hydrogel is conducive to rapid PMS capture and electron transport in advanced oxidation process, reducing the use of transition metal activator and limiting the leaching of metal ions. There is reason to believe that the synergistic activation of PMS by S-scheme heterojunction regulated by photoexcitation will provide a new perspective for future material design and research on enhancing heterologous catalysis oxidation process.

5.
Sci Rep ; 13(1): 15653, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730804

RESUMO

Indoor testing are performed to explore the charge induction law during the uniaxial compression fracture process of coal samples, and the charge time and frequency domain signals of coal samples with different primary fissures are analyzed in the paper. On-site monitoring of charge in different fissures distribution areas of underground coal tunnels, and the charge signals of different drillingdepths in coal seams are analyzed. The results show that the uniaxial compressive strength and elastic modulus of multi-fissured coal samples are less than those of less fissured coal samples, and the Poisson's ratio is greater than those of less fissured coal samples. The charge induction signal intensity during the fracture process of multi-fissured coal samples is relatively low, but it is concentrated at the low frequency of 0-50 Hz in the compacting elasticity stage. The charge signal intensity during the fracture process of coal samples with less fissure is relatively high, and the charge frequency during the reinforcement damage stage is concentrated at a low frequency of 0-50 Hz. Therefore, the sudden appearance of low-frequency charge signals is more suitable as effective precursor information for the instability and failure of less fissured coal bodies. The average charge intensity is small in the multi-fissured area with a drilling depth of 1-4 m in the coal seam, and the average charge intensity of the coal body with less fissures is larger in the 5-12 m region. The on-site charge monitoring results have good consistency with the indoor test results. This study has guiding significance in setting up a charge monitoring warning index of instability failure in different coal body fissures regions.

6.
Sci Rep ; 13(1): 12410, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37524999

RESUMO

To comprehensively understand the mechanical response of a rock-coal combination structure containing a weak layer, a series of laboratory static loading and impact loading experiments were conducted. The results showed that under static load, the sliding process of the rock coal structure was relatively slow, and fragments can be observed. Under the action of horizontal impact loading, the whole coal stratum slipped out rapidly, and the process lasted only 0.05 s. Under the horizontal and axial impact loads, the coal stratum remained stable first, and then it slipped out as a whole under the action of static load. Additionally, a sliding instability criterion of a rock coal structure containing a weak layer was established based on theoretical analysis. The key parameter P value was checked through a numerical simulation experiment. It was found that the value was linearly related to the mechanical properties of the weak layer and overburden stress, and the experimental results coincided with the theoretical results. Finally, the relationship between sliding rockburst and strain rockburst was discussed, and these results can provide an important scientific basis for the prevention and control of dynamic disasters in deep mining.

7.
J Exp Bot ; 74(12): 3667-3683, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-36912616

RESUMO

Pepper (Capsicum annuum) employs distinct defence responses against Ralstonia solanacearum infection (RSI); however, the mechanisms by which pepper activates these defence responses in a context-dependent manner is unclear. Here we study pepper plants defence response to RSI under room temperature-high humidity (RSRT, 28 °C / 90%) and high temperature-high humidity (RSHT, 37 °C / 90%) conditions, and non-infected plants under high temperature-high humidity (HTHH, 42 °C / 90%) stress. Herein, we found that the MADS-box transcription factor CaAGL8 was up-regulated by HTHH stress and RSRT or RSHT, and its silencing significantly reduced pepper thermotolerance and susceptibility to infection under both room and high temperature-high humidity (RSRT and RSHT). This was coupled with down-regulation of CaSTH2 and CaDEF1 upon RSRT, down-regulation of CaMgst3 and CaPRP1 upon RSHT, and down-regulation of CaHSP24 upon HTHH. In contrast, the ectopic overexpression of CaAGL8 significantly increased the resistance of Nicotiana benthamiana plants to RSRT, RSHT, and HTHH. In addition, CaAGL8 was found to interact with CaSWC4, which acted as a positive regulator of the pepper response to RSRT, RSHT, and HTHH. Silencing of either CaAGL8 or CaSWC4 blocked the hypersensitive response (HR) cell death and context-dependent up-regulation of defence-related genes triggered by the other. Importantly, enrichment of H4K5Ac, H3K9Ac, H3K4me3, and H3K9me2 on the tested defence-related genes was context- and gene-specifically regulated through synergistic interaction between CaSWC4 and CaAGL8. Our results indicate that pepper employs CaAGL8 to modulate chromatin remodelling by interacting with CaSWC4, thereby activating defence responses to RSRT, RSHT, and HTHH.


Assuntos
Capsicum , Ralstonia solanacearum , Termotolerância , Reguladores de Crescimento de Plantas/genética , Resistência à Doença/genética , Imunidade Vegetal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Montagem e Desmontagem da Cromatina , Cromatina , Capsicum/metabolismo , Doenças das Plantas , Regulação da Expressão Gênica de Plantas , Ralstonia solanacearum/fisiologia
8.
J Sport Rehabil ; 32(4): 449-461, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36791728

RESUMO

OBJECTIVES: To explore the immediate and retention effect of real-time tibial acceleration feedback on running biomechanics during gait retraining. METHODS: Five electronic databases were searched to identify relevant studies published before May 2022. The included studies were evaluated for methodological quality and bias risk, and data were extracted. A meta-analysis was conducted on the primary outcomes, including peak tibial acceleration (PTA) and vertical ground reaction force. Subgroup analysis was performed by gender, feedback criterion, mode, dosage, fading, retention period, and running environment to evaluate the source of heterogeneity. Qualitative analysis was performed to describe other variables. RESULTS: Fourteen studies (174 participants) were eligible. Meta-analysis showed that real-time tibial acceleration feedback reduced PTA (P < .01, P < .01), vertical impact peak (P = .004, P < .01), vertical average loading rate (P < .01, P < .01), and vertical instantaneous loading rate (P < .01, P < .01) after feedback and during retention period (5 min-12 mo). Subgroup analysis showed that the immediate effect of vertical impact peak was more noticeable with mixed gender (P = .005) and fading feedback (P = .005) conditions, and the retention effect of PTA was more noticeable with high feedback dosage (P < .01) and fading feedback (P < .01) conditions. CONCLUSIONS: Real-time tibial acceleration feedback can reduce PTA and vertical ground reaction force during gait retraining, and for periods of 5 minutes to 12 months when the feedback is removed.


Assuntos
Fraturas de Estresse , Corrida , Humanos , Retroalimentação , Fenômenos Biomecânicos , Marcha , Aceleração
9.
Clin Nurs Res ; 32(3): 629-638, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36169279

RESUMO

This study recruited 9,830 participants to identify whether the interaction between obesity and hypertension affects the occurrence of arteriosclerosis in Chinese adults. Brachial-ankle pulse wave velocity (baPWV) was measured to diagnose arteriosclerosis. Unconditional logistic regression was used for multiplicative interaction. The additive interaction was represented by relative excess risk due to interaction (RERI), attributable proportion (AP), and synergy (S). Hypertension was an independent risk factor for baPWV (p < .01), but obesity was not (p = .08). The interaction between obesity and hypertension on arteriosclerosis was not multiplicative (adjusted odds ratio = 0.89 (0.79-1.01), p = .07), but a negative additive interaction (RERI = -4.33, AP = -2.91, S = 0.10; p < .01) exists. Therefore, obesity may reduce the risk of arteriosclerosis caused by hypertension when hypertension and obesity coexist, especially in women and middle-aged people, which supports the obesity paradox.


Assuntos
Arteriosclerose , Hipertensão , Pessoa de Meia-Idade , Adulto , Humanos , Feminino , Estudos Transversais , Índice Tornozelo-Braço , População do Leste Asiático , Análise de Onda de Pulso , Hipertensão/complicações , Obesidade/complicações , Obesidade/epidemiologia , Arteriosclerose/complicações , Fatores de Risco
10.
Front Public Health ; 10: 1042236, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36504986

RESUMO

Objective: To compare the predictive performance of the percentage body fat (PBF), body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-hip ratio (WHR), waist-height ratio (WHtR), a body shape index (ABSI), body roundness index (BRI), abdominal volume index (AVI), and conicity index (CI) for identifying hypertension. Methods: A cross-sectional study was conducted among 2,801 adults (1,499 men and 1,302 women) aged 18 to 81 in Ningbo, China. The receiver operator characteristic (ROC) analysis and multiple non-parametric Z tests were used to compare the areas under the curve (AUC). The maximum Youden's indices were used to determine the optimal cut-off points of 10 obesity-related indices (ORI) for hypertension risk. Results: The AUC of all the indices were statistically significant (P < 0.05). The AUC of all the indices in men and women were 0.67-0.73 and 0.72-0.79, respectively. Further non-parametric Z tests showed that WHR had the highest AUC values in both men [0.73 (95% CI: 0.70, 0.76)] and women (0.79 (95% CI: 0.75, 0.83)], and several central ORI (men: WHR, WC, BRI, AVI, and CI, 0.71-0.73; women: WC, WHR, and AVI, 0.77-0.79) were higher than general ORI (PBF and BMI, 0.68 in men; 0.72-0.75 in women), with adjusted P < 0.05. The optimal cut-off points for identifying hypertension in men and women were as follows: PBF (23.55%, 32.55%), BMI (25.72 kg/m2, 23.46 kg/m2), HC (97.59 cm, 94.82 cm), WC (90.26 cm, 82.78 cm), WHR (0.91, 0.88), WHtR (0.51, 0.55), ABSI (0.08 m7/6/kg2/3, 0.08 m7/6/kg2/3), BRI (4.05, 4.32), AVI (16.31 cm2, 13.83 cm2), and CI (1.23 m2/3/kg1/2, 1.27 m2/3/kg1/2). Multivariate logistic regression models showed that all indices were statistically significant (P < 0.05) with the adjusted ORs (per 1-SD increase) at 1.39-2.06 and ORs (over the optimal cut-off points) at 1.80-2.64. Conclusions: All 10 ORI (PBF, BMI, HC, WC, WHR, WHtR, ABSI, BRI, AVI, and CI) can effectively predict hypertension, among which WHR should be recommended as the best predictor. Central ORI (WHR, WC, and AVI) had a better predictive performance than general ORIs (PBF and BMI) when predicting the risk of hypertension.


Assuntos
População do Leste Asiático , Hipertensão , Adulto , Masculino , Feminino , Humanos , Estudos Transversais , Curva ROC , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Obesidade/epidemiologia
11.
Front Public Health ; 10: 903036, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35769791

RESUMO

Objective: To compare the predictive performance of five handgrip strengths for cardiovascular disease (CVD) risk factors. Methods: A total of 804 Chinese middle-aged community residents' health medical examinations were collected. The absolute handgrip strength was denoted as HGS. HGS/body weight (HGS/BW), HGS/body mass index (HGS/BMI), HGS/lean body mass (HGS/LBM), and HGS/muscle mass (HGS/MM) represented relative handgrip strength (RHGS). To assess predictive performance, receiver operating characteristic (ROC) curves and the area under the curve (AUC) were constructed. Results: HGS was not associated with most CVD risk biomarkers; however, RHGS showed a negative correlation trend after controlling for covariates (sex, age, smoking, and exercise). HGS/BMI and HGS/BW had better AUCs for predicting CVD risk factors than HGS/LBM or HGS/MM. HGS/BMI and HGS/BW can successfully predict all CVD risk factors in men with AUCs 0.55-0.65; similarly, women may effectively predict arteriosclerosis, hyperglycemia, hyperuricemia, and metabolic syndrome with AUCs 0.59-0.64, all p < 0.05. The optimal HGS/BW cut-off points for identifying different CVD risk factors were 0.59-0.61 in men and 0.41-0.45 in women, while the HGS/BMI were 1.75-1.79 in men and 1.11-1.15 in women. Conclusions: Almost all CVD risk biomarkers and CVD risk factors were unrelated to HGS. There is, however, a significant inverse relationship between RHGS and CVD risk factors. HGS/BMI or HGS/BW should be recommended to be the best choice for predicting the risk of CVD risk factors in five expressions of handgrip strength. We also acquired the recommended optimal cut-off points of HGS/BMI and HGS/BW for predicting CVD risk factors.


Assuntos
Doenças Cardiovasculares , Força da Mão , Biomarcadores , Peso Corporal , Doenças Cardiovasculares/epidemiologia , China/epidemiologia , Feminino , Força da Mão/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
12.
J Am Pharm Assoc (2003) ; 62(1): 86-94.e4, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34688567

RESUMO

BACKGROUND: Burnout describes emotional exhaustion (EE), depersonalization (DP), and low personal achievement caused by work and is known to bring about negative consequences to practitioners, patients, and health systems. Various organizational and personal factors, such as organizational strategies and resilience, have been associated with this phenomenon. However, there is a paucity of data describing the prevalence of burnout among pharmacy staff within Singapore and Asia, especially in the pharmacy technician (PT) population. OBJECTIVES: This study aimed to (1) quantify burnout in PTs in patient-care sectors in Singapore and (2) explore factors that may be associated with burnout. METHODS: A cross-sectional survey among PTs in patient-care areas in Singapore, which includes hospitals, primary and secondary care institutions, and retail pharmacies, across both public and private sectors was conducted from February to April 2020. The Maslach Burnout Inventory - Human Services Survey and Brief Resilience Scale were used to assess burnout and resilience among participants. Demographic, employment, and well-being information were also collected and summarized. Univariate analysis and multivariate logistic regression were used to assess associations between burnout and potential risk and impact factors. RESULTS: Slightly more than half (52.0%) of PTs reported burnout (EE score ≥27 or DP ≥10 or both). Statistically significant factors associated with burnout include resilience, age, years of experience, ethnicity, marital status, nationality, highest qualifications, pharmacy-related certification, full-time employment status, and work hours. Impact associated with burnout includes intent for job change, job satisfaction, sleep, and presence of mental conditions. Statistically significant reported reasons for burnout and ways to build resilience were also elucidated. CONCLUSION: Burnout affects most PTs in Singapore and is primarily driven by workload and nature of their work, low resilience, and poor social support structures. National and organizational efforts are needed to arrest the vicious cycle that propagates burnout in PTs.


Assuntos
Esgotamento Profissional , Técnicos em Farmácia , Esgotamento Profissional/epidemiologia , Esgotamento Psicológico/epidemiologia , Estudos Transversais , Humanos , Satisfação no Emprego , Singapura/epidemiologia , Inquéritos e Questionários
13.
J Hazard Mater ; 426: 128106, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-34953261

RESUMO

Semiconductor photocatalytic degradation of pollutants is considered to be one of the promising sustainable energy routes. Nevertheless, it is challenging for photocatalysts to have excellent visible light absorption and suppress photo-generated electron-hole recombination at the same time. Here, we prepared nitrogen-doped ZnO carbon skeleton by directly calcining the metal-organic framework. Then hierarchical Bi2MoO6 nanosheets are grown in situ on its surface to synthesize S-scheme heterojunction. This special 3D layered and oxygen vacancies work together to make photo-generated electrons and holes easier to separate and migrate. Therefore, the pseudo-first-order kinetic constant of N-doped ZnO carbon skeleton@Bi2MoO6 degradation of sulfamethoxazole reaches 0.022 min-1, which is almost 10 times that of ZIF-8 derived ZnO and 27.5 times Bi2MoO6 under visible light irradiation. Meanwhile, the mechanism of driving charge transfer of S-scheme heterojunction, and the photocatalytic degradation pathway of sulfamethoxazole are also analyzed. This work will provide a new way to construct S-scheme heterojunction photocatalyst to degrade antibiotic pollutants.


Assuntos
Óxido de Zinco , Bismuto , Carbono , Catálise , Teoria da Densidade Funcional , Molibdênio , Fotólise , Esqueleto , Sulfametoxazol
14.
Artigo em Inglês | MEDLINE | ID: mdl-34501516

RESUMO

This study aimed to assess the predictive performance and establish optimal cut-off points of blood pressure for identifying arteriosclerosis in eastern Chinese adults. Brachial-ankle pulse wave velocity (baPWV) was utilized to evaluate arteriosclerosis. The predictive performance of blood pressure for arteriosclerosis was determined by the area under the curve (AUC) of receiver operating characteristics; the optimal blood pressure cut-off points were determined by Youden's index. A logistic regression model was used to acquire the odds ratio (OR) of blood pressure for arteriosclerosis. The AUCs of blood pressure for identifying arteriosclerosis were 0.868 (95%CI: 0.860-0.875) for systolic blood pressure (SBP) and 0.835 (95%CI: 0.827-0.843) for diastolic blood pressure (DBP), both p < 0.01. The AUCs of women were higher than that of men (0.903 vs. 0.819 for SBP; 0.847 vs. 0.806 for DBP; Z test p < 0.05). The AUCs in the 18-39.9-years group were higher than that in the 40-59.9-years and 60-84-years groups (0.894 vs. 0.842 and 0.818 for SBP; 0.889 vs. 0.818 and 0.759 for DBP; Z test p < 0.05). The total optimal cut-off points of blood pressure for predicting arteriosclerosis were 123.5/73.5 mmHg (SBP/DBP) overall; 123.5/73.5 and 126.5/79.5 mmHg for women and men, respectively; and 120.5/73.5, 123.5/76.5, and 126.5/75.5 mmHg for 18-39.9-years, 40-59.9-years, and 60-84-years groups, respectively. Blood pressure indexes had a high predictive performance for identifying arteriosclerosis with the optimal cut-off point of 123.5/73.5 mmHg (SBP/DBP) in eastern Chinese adults. Women or the younger population have a higher predictive performance and lower cut-off points to identify arteriosclerosis.


Assuntos
Arteriosclerose , Hipertensão , Adulto , Índice Tornozelo-Braço , Arteriosclerose/diagnóstico , Arteriosclerose/epidemiologia , Pressão Sanguínea , China/epidemiologia , Feminino , Humanos , Masculino , Análise de Onda de Pulso
15.
Front Psychol ; 12: 644188, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34526927

RESUMO

Hazardous knee biomechanics, such as excessive knee affordance link with injuries in volleyball spike jumps (SPJs) and can be reconfigured by the enhancement of internal focus. The study aimed to explore the effects of video tasks illustrating a high-level SPJ on knee movement in the volleyball SPJ with 15 elite male volleyball athletes. This study investigated the knee movements in sagittal, coronal, and transverse planes before and after the video task in SPJ using one-dimensional statistical parametric mapping (SPM 1D) and discrete statistics. The SPM 1D indicated a larger knee flexion angle (31.17-73.19%, t = 2.611, and p = 0.012), increased knee flexion moment (19.72-21.38%, t = 0.029, and p = 0.029), and increased knee adduction angular velocity (49.07-62.64%, t = 3.148, and p = 0.004) after video task; alternatively, smaller knee external rotation angular velocity (45.85-49.96%, t = 5.199, and p = 0.017) and vertical ground reaction (vGRF) (3.13-5.94%, t = 4.096, and p = 0.014; 19.83-21.97%, t = 4.096, and p = 0.024) were found after the task. With discrete value statistics, the video task increased the peak of knee flexion angle while decreased the peak of extension moment, flexion moment, abduction moment, external moment, the first peak vGRF, and related loading rate. Conclusions: The results indicate that knee biomechanics in volleyball SPJ positively influenced by the video task. The task has the athletes control the knee movements more actively and improves the original hazardous movement strategies. Therefore, the video task presumably can abate the occurrence of knee injuries in volleyball SPJ. Further validation especially in the exercise effect is needed in the future.

16.
Front Psychol ; 12: 669119, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335381

RESUMO

BACKGROUND: The coronavirus disease (COVID-19) pandemic has been spreading and brought unprecedented psychological pressure on people across the entire globe since December 2019. OBJECTIVES: To synthesize the existing evidence of the prevalence of mental health status during the epidemic and provide the basis for mental health education. MATERIALS AND METHODS: The literature search was conducted in nine databases from December 2019 to October 2020. The risk of bias for each study was assessed, and the random-effects meta-analysis was used to estimate the prevalence of specific mental health problems. The review protocol was registered in PROSPERO with the registration number CRD42020208619. RESULTS: About 27 studies were included in the analysis with a total of 706,415 participants combined, and 14 mental health problems were gathered. Meta-analysis showed that the prevalence of depression was 39% (95% CI: 27-51%) and that of anxiety was 36% (95% CI: 26-46%). Subgroup analysis indicated that the prevalence of depression and anxiety varied among nations and due to the survey date. The prevalence of depression (60%, 95% CI: 46-74%) and anxiety (60%, 95% CI: 46-74%) in non-Chinese college students was higher than those in Chinese college students (26%, 95% CI: 21-30% and 20%, 95% CI: 14-26%). The proportion of depression (54%, 95% CI: 40-67%) and anxiety (37%, 95% CI: 26-48%) was higher after March 1 than before it (21%, 95% CI: 16-25% and 19%, 95% CI: 13-25%). CONCLUSIONS: The meta-analysis results presented that the prevalence of depression (39%) or anxiety (36%) among college students greatly increased during the COVID-19 pandemic. In addition, the mental health of college students is affected by the nations and the survey date. It was necessary to take measures to reduce mental health risks during the pandemic.

17.
Life (Basel) ; 11(7)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34357085

RESUMO

Although the impact of physical exercise on blood lipids is well documented, less information is available regarding the effect of traditional Chinese exercises (TCEs), and it is unclear what the best TCE treatment for dyslipidemia in middle-aged and elderly individuals is. The aim of this study was to systematically assess the effects of TCEs (Taijiquan, TJQ; Wuqinxi, WQX; Baduanjin, BDJ; Liuzijue, LZJ; Yijinjing, YJJ; Dawu, DW) on blood lipids in middle-aged and elderly individuals. Chinese and English databases were searched, including PubMed, China National Knowledge Infrastructure, Wanfang Database, Chongqing VIP, and Web of Science. A total of 42 randomized controlled trials (RCTs) including 2977 subjects were analyzed. Outcome indicators include total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triacylglyceride (TAG), and high-density lipoprotein cholesterol (HDL-C). Summary mean differences (MD) were calculated using pairwise and network meta-analysis with a random-effects model. The results of this study showed that compared to non-exercise intervention (NEI), all six kinds of TCE treatment had some kind of influence on blood lipid indicators, among which WQX and TJQ could improve all four blood lipid indicators, whereas BDJ was effective on three indicators but not on TC. The results of cumulative probability ranking showed that WQX (84.9%, 73.8%, 63.4%, 63.1% to TC, TAG, HDL-C, LDL-C, respectively) was at the top spot being the best intervention, followed by BDJ (55.6%, 83.7%, 68.4%, 56.1%) and TJQ (73.7%, 47.6%, 63.1%, 54.1%). The network meta-analysis of RCTs demonstrates that WQX may be the best TCE treatment for dyslipidemia in middle-aged and elderly individuals.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34300094

RESUMO

(1) Objective: Our objective was to conduct a meta-analysis of randomized controlled trials that have evaluated the benefits of exercise training for elderly pulmonary fibrosis (PF) patients. (2) Methods: Studies in either English or Chinese were retrieved from the China National Knowledge Infrastructure (CNKI) and the Wanfang, PubMed, Web of Science and SPORTDiscus databases from inception until the first week of April 2021. Age, body mass index (BMI), and exercise frequency, intensity, type, and duration were considered for each participant. The specific data recorded were the six-minute walk distance (6MWD), maximal rate of oxygen consumption (peak VO2), predicted forced vital capacity (FVC% pred), predicted diffusing capacity of the lung for carbon monoxide (DLCO% pred), predicted total lung capacity (TLC% pred), St. George's respiratory questionnaire (SGRQ) total score and a modified medical research council score (mMRC). (3) Results: Thirteen studies comprised this meta-analysis (eleven randomized controlled trials and two prospective studies design), wherein 335 patients were exercised and 334 were controls. The results showed that exercise training increased the 6MWD (Cohen's d = 0.77, MD = 34.04 (95% CI, 26.50-41.58), p < 0.01), peak VO2 (Cohen's d = 0.45, MD = 1.13 (95% CI, 0.45-1.82), p = 0.0001) and FVC% pred (Cohen's d = 0.42, MD = 3.94 (95% CI, 0.91-6.96), p = 0.01). However, exercise training reduced scores for the SGRQ (Cohen's d = 0.89, MD = -8.79 (95% CI, -10.37 to -7.21), p < 0.01) and the mMRC (Cohen's d = 0.64, MD = -0.58 (95% CI, -0.79 to -0.36), p < 0.01). In contrast, exercise training could not increase DLCO% pred (Cohen's d = 0.16, MD = 1.86 (95% CI, -0.37-4.09), p = 0.10) and TLC% pred (Cohen's d = 0.02, MD = 0.07 (95% CI, -6.53-6.67), p = 0.98). Subgroup analysis showed significant differences in frequency, intensity, type, and age in the 6MWD results (p < 0.05), which were higher with low frequency, moderate intensity, aerobic-resistance-flexibility-breathing exercises and age ≤ 70. Meanwhile, the subgroup analysis showed significant differences in exercise intensity and types in the mMRC results (p < 0.05), which were lower with moderate intensity and aerobic-resistance exercises. (4) Conclusions: Exercise training during pulmonary rehabilitation can improved cardiopulmonary endurance and quality of life in elderly patients with PF. The 6MWDs were more noticeable with moderate exercise intensity, combined aerobic-resistance-flexibility-breathing exercises and in younger patients, which all were not affected by BMI levels or exercise durations. As to pulmonary function, exercise training can improve FVC% pred, but has no effect on DLCO% pred and TLC% pred.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Fibrose Pulmonar , Idoso , China , Exercício Físico , Tolerância ao Exercício , Humanos , Estudos Prospectivos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Brain Sci ; 11(5)2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-33922951

RESUMO

Poor knee biomechanics in a volleyball spike jump generally result in a higher knee injury risk, which can be altered by an internal focus of attention (FOA). The constrained action hypothesis (CAH) purports that the FOA inhibits sports performance whereas no ecologically valid evidence has been found in previous studies. The purpose of this research is to explore the effect of video feedback on knee biomechanics in a volleyball spike jump including landing and take-off phases. The video feedback was performed in a natural way. Fourteen volleyball male players were recruited in this study. A paired t-test was used to detect the effect of the feedback; meanwhile, statistical parameter mapping (SPM) statistics were used for the continuum differences during movement. After biofeedback, the initial contact flexion angle of the knee (t = 2.179, p = 0.049), the maximal flexion angle of the knee (t = 3.242, p = 0.006) and the maximal internal rotation angular velocity of the knee (t = 5.209, p = 0.003) increased significantly; the maximal extension moment of the knee (t = 3.962, p < 0.001) and the maximal flexion moment of the knee (t = -3.711, p = 0.002) significantly decreased; the maximal abduction moment significantly decreased (t = 3.069, p = 0.037) but the maximal internal rotation moment significantly increased (t = 2.813, p = 0.018); the first peak of the vertical ground reaction force (vGRF) (t = 7.618, p < 0.001) and the average loading rate to the first peak (t = 4.205, p = 0.004) significantly decreased; the other peaks of the vGRF were not found to have differences; a larger knee flexion was found during the phase from 31.17 to 73.19% (t = 2.611, p = 0.012); a larger adduction angular velocity was found during the phase from 49.07 to 62.46% (t = 3.148, p = 0.004); a smaller external rotational angular velocity was found during the phase from 45.85 to 49.96% (t = 5.011 p = 0.017); there was an increased flexion moment of the knee during the phase from 19.72 to 21.38% (t = 0.029, p = 0.029) and an external moment of the knee during the phase from 85.55 to 95.06% (t = 4.214, p < 0.001); the vGRF significantly decreased during the phase from 3.13 to 5.94% (t = 4.096, p = 0.014) and 19.83-21.97% (t = 4.096, p = 0.024) but significantly increased in the phase of 91.43-100% (t = 4.096, p < 0.001). The impulse of the vGRF and knee power were not found to be different compared with before biofeedback. Therefore, our study suggests video feedback in a natural practice has the potential to improve knee movement whilst not altering the performance in a volleyball spike jump. This indicates that the CAH theory is possibly not suitable in a real competition. Due to the complexity of human movements and the limitations of this study, muscle activities must be considered in the future.

20.
Artigo em Inglês | MEDLINE | ID: mdl-33503914

RESUMO

Physical activity has been suggested to be beneficial in preventing disease and improving body function in older people. Older people's leisure-time physical activity (LTPA) is affected by various factors, especially environmental factors. However, the differences in the association between older people's LTPA and the built environment in different sex groups remain unclear. Perceived built environment scores and older people's LTPA were collected for 240 older people in Jinhua using the Neighborhood Environment Walkability Scale and International Physical Activity Questionnaire, respectively. A linear regression method was used to analyze the associations between older people's LTPA and the built environment in men, women, and all participants. The results showed that land use mix diversity was associated with LTPA in older people for both sexes. In men, LTPA was also associated with access to services. However, in women, LTPA was associated with residential density, street connectivity, and crime safety. The relationship varied when demographic variables were incorporated into the regression analysis. Those results indicated that a shorter perceived distance from home to destination would motivate older people to engage more in LTPA. Older people's LTPA was affected by various built environment factors according to different sex groups. Women's LTPA was generally more sensitive to the built environment. More studies are needed to confirm the association between LTPA in older people and the built environment in men and women in mid- or small-sized Chinese cities in the future.


Assuntos
Ambiente Construído , Caminhada , Idoso , Idoso de 80 Anos ou mais , China , Cidades , Estudos Transversais , Planejamento Ambiental , Exercício Físico , Feminino , Humanos , Atividades de Lazer , Masculino , Características de Residência
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