Background High-speed train engineers' lower extremities are constrained by compulsive vigilance pedal tasks and limited space beneath the control console during driving. Shifts in alertness triggered by running route observation may share the same mental resource required by moderate-to-low physical exertion. Current research on improving cab design and maintaining optimal on-duty attention allocation remains limited. Objective To examine variations in lower extremity muscle load, gaze-tracking behavior, and driving performance under various combinations of vigilance pedal positions and route scenarios during simulated high-speed train tasks. To identify optimal working condition combinations that promote level and variety of physical activity and facilitate rational attention allocation. Methods A 4×2 within-subjects design were employed (4 vigilance pedal position profiles: knee front, side, and any; 2 route scenarios: monotonous and complex). Nine male college volunteers were recruited as simulated drivers to perform designated interval driving tasks. Surface electromyography and eye tracking were used to assess leg muscle load and gaze behavior respectively. Task performance and subjective fatigue were recorded. Results In all simulation driving tasks, skeletal muscle loads were low with the percentage of maximum voluntary contraction (%MVC) at approximately 4%. No fatigue tendencies were observed within single trial blocks (7 min), and the subjective fatigue ratings remained relatively low. While the activation of the dominant-side tibialis anterior was higher for the knee pedal than for the front (%MVC: 3.7% ± 3.13% vs. 1.08% ± 0.72%) or the side pedals (%MVC: 3.7% ± 3.13% vs. 1.4% ± 0.77%). The activation level of the dominant-side gastrocnemius was higher for the knee pedal than for the other three pedal profiles. For the any pedal condition, the intercept of the instantaneous median frequency curve for the dominant-side rectus femoris was lower in the monotonous route than in the complex route [(111.18 ± 35.78) Hz vs. (153.33 ± 39.12) Hz]. Among eye-tracking metrics, total fixations were higher during knee-level pedaling than side pedaling, while more saccades were recorded in monotonous routes than in complex ones. Regarding task performance, the any pedal yielded fewer missed signals than the front pedal, with 2/3 and 1/3 of participants preferring the front and knee pedals, respectively. The activation levels of the dominant tibialis anterior and dominant gastrocnemius muscles during the knee pedal × complex route combination were higher than any combination involving the front pedal. No statistically significant effect of pedal position or route scenario was found on other indicators. Conclusion The combination of knee pedal and complex route provides an optimal working setting for maximizing leg muscle mobility without compromising attention allocation or driving performance. It is recommended that train engineers modulate attention during monotonous routes to avoid emotional tension and increased muscle strain caused by over-monitoring. Given the ergonomic characteristics of high cognitive load, low physical exertion levels, and highly restricted lower limb mobility among high-speed train engineers, future cab designs should consider incorporating knee-level vigilance pedal and adjust safety alertness rules to allow reset via either front or knee pedal.

Background High-speed train engineers' lower extremities are constrained by compulsive vigilance pedal tasks and limited space beneath the control console during driving. Shifts in alertness triggered by running route observation may share the same mental resource required by moderate-to-low physical exertion. Current research on improving cab design and maintaining optimal on-duty attention allocation remains limited. Objective To examine variations in lower extremity muscle load, gaze-tracking behavior, and driving performance under various combinations of vigilance pedal positions and route scenarios during simulated high-speed train tasks. To identify optimal working condition combinations that promote level and variety of physical activity and facilitate rational attention allocation. Methods A 4×2 within-subjects design were employed (4 vigilance pedal position profiles: knee front, side, and any; 2 route scenarios: monotonous and complex). Nine male college volunteers were recruited as simulated drivers to perform designated interval driving tasks. Surface electromyography and eye tracking were used to assess leg muscle load and gaze behavior respectively. Task performance and subjective fatigue were recorded. Results In all simulation driving tasks, skeletal muscle loads were low with the percentage of maximum voluntary contraction (%MVC) at approximately 4%. No fatigue tendencies were observed within single trial blocks (7 min), and the subjective fatigue ratings remained relatively low. While the activation of the dominant-side tibialis anterior was higher for the knee pedal than for the front (%MVC: 3.7% ± 3.13% vs. 1.08% ± 0.72%) or the side pedals (%MVC: 3.7% ± 3.13% vs. 1.4% ± 0.77%). The activation level of the dominant-side gastrocnemius was higher for the knee pedal than for the other three pedal profiles. For the any pedal condition, the intercept of the instantaneous median frequency curve for the dominant-side rectus femoris was lower in the monotonous route than in the complex route [(111.18 ± 35.78) Hz vs. (153.33 ± 39.12) Hz]. Among eye-tracking metrics, total fixations were higher during knee-level pedaling than side pedaling, while more saccades were recorded in monotonous routes than in complex ones. Regarding task performance, the any pedal yielded fewer missed signals than the front pedal, with 2/3 and 1/3 of participants preferring the front and knee pedals, respectively. The activation levels of the dominant tibialis anterior and dominant gastrocnemius muscles during the knee pedal × complex route combination were higher than any combination involving the front pedal. No statistically significant effect of pedal position or route scenario was found on other indicators. Conclusion The combination of knee pedal and complex route provides an optimal working setting for maximizing leg muscle mobility without compromising attention allocation or driving performance. It is recommended that train engineers modulate attention during monotonous routes to avoid emotional tension and increased muscle strain caused by over-monitoring. Given the ergonomic characteristics of high cognitive load, low physical exertion levels, and highly restricted lower limb mobility among high-speed train engineers, future cab designs should consider incorporating knee-level vigilance pedal and adjust safety alertness rules to allow reset via either front or knee pedal.

Background The neck, shoulders, and lower back are the primary affected areas of work-related musculoskeletal disorders. In manual tasks, combinations of hand functional height (defined as working height below the waist), awkward postures, and cognitive load are common risk factors. However, there is limited literature documenting how these factors specifically alter biomechanical load on the neck, shoulders, and lower back when working at hand functional height. Objective To explore quantitative differences in biomechanical load on the neck, shoulders, and lower back of workers performing manual tasks at hand functional height under different postures and cognitive load combinations. Methods A 3x2 within-subject design was implemented, with three postures (squat, kneeling, and stoop) and two levels of cognitive load (with cognitive load induced by a 2back task and without cognitive load). Ten male university students were recruited to perform a predetermined assembly task (a sequence of loosening and tightening screws) at hand functional height. Surface electromyography (sEMG) and 3D motion capture system were employed to assess the participants’ trunk biomechanical load in executing the tasks. Additionally, subjective perception, including fatigue, muscle pain, and cognitive load, were evaluated using scales. Results Significant variations in biomechanical load were observed across the three postures (P<0.05). The stoop posture exhibited the lowest muscle activation in most target muscles, except for the sternocleidomastoid, and showed the fastest decline in instantaneous median frequency (IMF) of the erector spinae, with a rate of (-0.050±0.008) Hz per unit time (0.128 s), and the greatest trunk flexion angle (35.14°±4.40°). Performing the task by squatting resulted in the highest muscle activation, especially in the upper trapezius, where maximum voluntary contraction percentage reached 20.07%±1.26%. In addition, the squatting posture also resulted in larger joint angles in the sagittal plane for the neck (−7.03°±2.70°), shoulders (60.20°±7.89°), and lower back (34.42°±4.20°). The kneeling posture showed intermediate muscle activation, the slowest IMF decline for the erector spinae in the lower back (−0.005±0.008) Hz per unit time (0.128s), and the joint angles were closest to neutral. The task performance results were also superior in the kneeling posture. Regarding cognitive load, no significant differences were found for most biomechanical indicators, except for subjective cognitive load scores, neck flexion, and shoulder external rotation angles. Conclusion In assembly tasks performed at hand functional height, kneeling results in moderate biomechanical load on the neck, shoulders, and lower back while also improves task performance compared to squatting and forward bending. Additionally, no significant effects of cognitive load under the 2back condition on biomechanical load are observed.

BACKGROUND:Intestinal flora is a diverse and dynamic microbial community located in the human gastrointestinal tract,which plays a crucial role in maintaining human immunity and health.In recent years,the concept of"gut-lung axis"has been proposed,suggesting that intestinal flora is closely related to the lung,and exercise can regulate respiratory diseases by maintaining the balance of intestinal flora.OBJECTIVE:To review the relationship between intestinal flora and different respiratory diseases such as pneumonia,lung cancer,asthma and chronic pulmonary obstruction,and the influence of different exercise modes on intestinal flora and respiratory diseases,providing new ideas for an in-depth exploration of the mechanisms by which exercise regulates the role of intestinal flora in respiratory diseases.METHODS:CNKI and PubMed databases were searched for relevant literature published from 1944 to 2024,using the search terms of"intestinal flora,gut bacteria,respiratory illness,pneumonia,lung cancer,asthma,chronic obstructive pulmonary diseases,aerobic exercise,resistance training"in Chinese and English,respectively.Totally 101 documents were included according to inclusion and exclusion criteria.RESULTS AND CONCLUSION:(1)Intestinal flora plays an important role in the regulation of respiratory diseases such as pneumonia,lung cancer,asthma and chronic pulmonary obstruction diseases.(2)Different exercise modes are closely related to intestinal flora.Aerobic exercise can play a beneficial role in the regulation of intestinal flora by improving insulin sensitivity,increasing microbial diversity and inhibiting systemic chronic inflammation.Resistance exercise can decrease the permeability of intestinal mucosa and promote the production of short-chain fatty acids.Aerobic exercise combined with resistance exercise can also increase the diversity of intestinal flora and affect the composition of intestinal flora.(3)Exercise can improve respiratory diseases by regulating inflammatory response and reducing oxidative stress damage as well as improving cardiopulmonary function and exercise performance.(4)Exercise plays a key role in the prevention and treatment of respiratory diseases by regulating intestinal flora,inhibiting inflammatory response,regulating oxidative stress,improving intestinal barrier permeability and maintaining intestinal flora homeostasis.

BACKGROUND:Intestinal flora is a diverse and dynamic microbial community located in the human gastrointestinal tract,which plays a crucial role in maintaining human immunity and health.In recent years,the concept of"gut-lung axis"has been proposed,suggesting that intestinal flora is closely related to the lung,and exercise can regulate respiratory diseases by maintaining the balance of intestinal flora.OBJECTIVE:To review the relationship between intestinal flora and different respiratory diseases such as pneumonia,lung cancer,asthma and chronic pulmonary obstruction,and the influence of different exercise modes on intestinal flora and respiratory diseases,providing new ideas for an in-depth exploration of the mechanisms by which exercise regulates the role of intestinal flora in respiratory diseases.METHODS:CNKI and PubMed databases were searched for relevant literature published from 1944 to 2024,using the search terms of"intestinal flora,gut bacteria,respiratory illness,pneumonia,lung cancer,asthma,chronic obstructive pulmonary diseases,aerobic exercise,resistance training"in Chinese and English,respectively.Totally 101 documents were included according to inclusion and exclusion criteria.RESULTS AND CONCLUSION:(1)Intestinal flora plays an important role in the regulation of respiratory diseases such as pneumonia,lung cancer,asthma and chronic pulmonary obstruction diseases.(2)Different exercise modes are closely related to intestinal flora.Aerobic exercise can play a beneficial role in the regulation of intestinal flora by improving insulin sensitivity,increasing microbial diversity and inhibiting systemic chronic inflammation.Resistance exercise can decrease the permeability of intestinal mucosa and promote the production of short-chain fatty acids.Aerobic exercise combined with resistance exercise can also increase the diversity of intestinal flora and affect the composition of intestinal flora.(3)Exercise can improve respiratory diseases by regulating inflammatory response and reducing oxidative stress damage as well as improving cardiopulmonary function and exercise performance.(4)Exercise plays a key role in the prevention and treatment of respiratory diseases by regulating intestinal flora,inhibiting inflammatory response,regulating oxidative stress,improving intestinal barrier permeability and maintaining intestinal flora homeostasis.

Objective To explore the impact of ten-eleven translocation 2(TET2)mutations on imiquimod(IMQ)-induced psoriatic skin inflammation using a TET2-knockout(TET2-/-)mouse model.Methods Mice were divided randomly into a wild-type(WT)vaseline group,WT imiquimod group,TET2-/-vaseline group,and TET2-/-imiquimod group.IMQ was used to establish a psoriasis-like dermatitis model,and the degree of skin lesions and pathological changes in mice in the WT imiquimod and TET2-/-imiquimod groups were observed and compared daily during the modeling period.The mice were sacrificed when the phenotype had reached the peak and the spleen index was recorded in each group.Gene expression levels of the inflammatory factors tumor necrosis factor(TNF)-α,interleukin(IL)-6,IL-17A,and IL-23 in mouse back lesions were detected by quantitative reverse transcription polymerase chain reaction.Skin histopathology was compared in hematoxylin/eosin-stained sections.IL-17,interferon(INF)-γ,and TNF-α protein expression levels in the back skin of mice in the four groups were detected by immunohistochemistry.The ultrastructure of the dermis and epidermis was observed using transmission electron microscopy.Results TET2 expression was down-regulated in skin lesions in WT imiquimod group.Dermatitis lesions were more severe and progressed faster in TET2-/-imiquimod group compared with WT imiquimod group,and the psoriasis area and severity index score and spleen index were both higher.mRNA expression levels of TNF-α,IL-6,IL-17A,and IL-23 in skin lesions were higher and epidermal thickening and inflammatory cell infiltration were increased,and protein expression levels of IL-17,INF-γ,and TNF-α were significantly higher in skin lesions in TET2-/-imiquimod group compared with WT imiquimod group.In addition,cell junctions were absent in skin lesions in TET2-/-imiquimod group and mitochondrial ridges were broken and dissolved,mitochondrial vacuoles were present,and the texture of the mitochondrial membrane was darker.Conclusions Loss of TET2 promotes the inflammatory response and exacerbates IMQ-induced psoriasis-like dermatitis injury in mice.

Objective To analyze stroke-related risk factors and their impact on urban community residents in Beijing,focusing on chronic diseases,psychological health,and quality of life,to provide evidence for community screening and intervention strategies.Methods Data were collected from residents aged 50+in 19 communities by using questionnaires and a WeChat App.Propensity score matching(PSM)balanced baseline characteristics.Logistic regression(univariate and stepwise)and mediation effect analysis were conducted by using SPSS and R.Results After PSM,87 stroke cases and 348 controls showed balanced baseline characteristics.The stroke group had higher chronic disease prevalence and lower psychological and quality of life scores.Hypertension increased stroke risk(P=0.002).Cognitive-12 Scale(Cog-12)was positively,and European Quality of Life-5 Dimensions(EQ-5D)negatively,associated with stroke(P＜0.001).Hypertension mediated stroke risk through Cog-12 and EQ-5D,with EQ-5D contributing 26.72％.Conclusion In this urban community study,stroke prevention should focus on managing chronic diseases,improving cognitive health and quality of life,and addressing psychological health.Digital tools can enhance follow-up and assessment,optimizing community-based stroke management strategies.

Objective To explore the impact of ten-eleven translocation 2(TET2)mutations on imiquimod(IMQ)-induced psoriatic skin inflammation using a TET2-knockout(TET2-/-)mouse model.Methods Mice were divided randomly into a wild-type(WT)vaseline group,WT imiquimod group,TET2-/-vaseline group,and TET2-/-imiquimod group.IMQ was used to establish a psoriasis-like dermatitis model,and the degree of skin lesions and pathological changes in mice in the WT imiquimod and TET2-/-imiquimod groups were observed and compared daily during the modeling period.The mice were sacrificed when the phenotype had reached the peak and the spleen index was recorded in each group.Gene expression levels of the inflammatory factors tumor necrosis factor(TNF)-α,interleukin(IL)-6,IL-17A,and IL-23 in mouse back lesions were detected by quantitative reverse transcription polymerase chain reaction.Skin histopathology was compared in hematoxylin/eosin-stained sections.IL-17,interferon(INF)-γ,and TNF-α protein expression levels in the back skin of mice in the four groups were detected by immunohistochemistry.The ultrastructure of the dermis and epidermis was observed using transmission electron microscopy.Results TET2 expression was down-regulated in skin lesions in WT imiquimod group.Dermatitis lesions were more severe and progressed faster in TET2-/-imiquimod group compared with WT imiquimod group,and the psoriasis area and severity index score and spleen index were both higher.mRNA expression levels of TNF-α,IL-6,IL-17A,and IL-23 in skin lesions were higher and epidermal thickening and inflammatory cell infiltration were increased,and protein expression levels of IL-17,INF-γ,and TNF-α were significantly higher in skin lesions in TET2-/-imiquimod group compared with WT imiquimod group.In addition,cell junctions were absent in skin lesions in TET2-/-imiquimod group and mitochondrial ridges were broken and dissolved,mitochondrial vacuoles were present,and the texture of the mitochondrial membrane was darker.Conclusions Loss of TET2 promotes the inflammatory response and exacerbates IMQ-induced psoriasis-like dermatitis injury in mice.

Objective To analyze stroke-related risk factors and their impact on urban community residents in Beijing,focusing on chronic diseases,psychological health,and quality of life,to provide evidence for community screening and intervention strategies.Methods Data were collected from residents aged 50+in 19 communities by using questionnaires and a WeChat App.Propensity score matching(PSM)balanced baseline characteristics.Logistic regression(univariate and stepwise)and mediation effect analysis were conducted by using SPSS and R.Results After PSM,87 stroke cases and 348 controls showed balanced baseline characteristics.The stroke group had higher chronic disease prevalence and lower psychological and quality of life scores.Hypertension increased stroke risk(P=0.002).Cognitive-12 Scale(Cog-12)was positively,and European Quality of Life-5 Dimensions(EQ-5D)negatively,associated with stroke(P＜0.001).Hypertension mediated stroke risk through Cog-12 and EQ-5D,with EQ-5D contributing 26.72％.Conclusion In this urban community study,stroke prevention should focus on managing chronic diseases,improving cognitive health and quality of life,and addressing psychological health.Digital tools can enhance follow-up and assessment,optimizing community-based stroke management strategies.

Iron is an essential element for living organisms that plays critical roles in the process of bacterial growth and metabolism. However, it remains to be elucidated whether piuB encoding iron-uptake factor is involved in iron uptake and pathogenicity of Xanthomonas axonopodis pv. glycines (Xag). To investigate the function of piuB, we firstly generated a piuB deletion mutant (ΔpiuB) by homologous recombination. Compared with the wild-type, the piuB mutant exhibited significantly reduced growth and virulence in host soybean. The mutant displayed markedly increased siderophore secretory volume, and its sensitivity to Fe³⁺, Cu²⁺, Zn²⁺ and Mn²⁺ was significantly enhanced. Additionally, the H₂O₂ resistance, exopolysaccharide yield, biofilm formation, and cell mobility of ΔpiuB were significantly diminished compared to that of the wild-type. The addition of exogenous Fe³⁺ cannot effectively restore the above characteristics of ΔpiuB. However, expressing piuB in trans rescued the properties lost by ΔpiuB to the levels in the wild-type. Taken together, our results demonstrated that PiuB is a potential factor for Xag to assimilate Fe³⁺, and is necessary for Xag to be pathogenic in host soybean.
Iron ; Glycine max ; Virulence ; Xanthomonas axonopodis/genetics* ; Hydrogen Peroxide