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.

In current clinical practice, various dermal templates and skin substitutes are used to enhance wound healing. However, the role of wound commensal microbiome in regulating scaffold performance and the healing process remains unclear. In this study, we investigated the influence of both natural and synthetic scaffolds on the wound commensal microbiome and wound repair in three distinct models including diabetic wounds, burn injuries, and germ-free (GF) wounds. Remarkably, synthetic electrospun polycaprolactone (PCL) scaffolds were observed to positively promote microbiome diversity, leading to enhanced diabetic wound healing compared to the natural scaffolds Integra® (INT) and MatriDerm® (MAD). In contrast, both natural and synthetic scaffolds exhibited comparable effects on the diversity of the microbiome and the healing of burn injuries. In GF wounds with no detectable microorganisms, a reversed healing rate was noted showing natural scaffold (MAD) accelerated wound repair compared to the open or the synthetic scaffold (PCL) treatment. Furthermore, the response of the wound commensal microbiome to PCL scaffolds appears pivotal in promoting anti-inflammatory factors during diabetic wound healing. Our results emphasize that the wound commensal microbiome, mediated by different scaffolds plays an important role in the wound healing process.

Objective:To establish an arsenic free fully automatic online digestion iodine analyzer detection method for urinary iodine (hereinafter referred to as the method).Methods:Based on the principle of iodine catalyzed antimony cerium redox reaction, a fully automatic online digestion iodine analyzer was used to determine the iodine content in urine. The effectiveness of the method in terms of detection limit, precision, accuracy (determination of urinary iodine primary standard reference materials GBW09108z and GBW09110f and spiked recovery experiment), and interference experiments was validated. The method was compared with the arsenic cerium catalytic spectrophotometry method recommended by the National Reference Laboratory for Iodine Deficiency Disorders.Results:The linear range of the method was 0 - 300 μg/L, with a correlation coefficient │ r│> 0.999 5. The qualitative and quantitative detection limits were 7.41 and 18.01 μg/L, respectively. The relative standard deviation ( RSD) of urine samples with different iodine concentrations ranged from 1.0% to 1.7%. The results of the determination of iodine concentrations in urine using standard substances GBW09108z and GBW09110f were within the given standard range, with RSD < 2.5%. The range of spiked recovery rates for urine samples with different iodine concentrations was 101.3% to 104.8%, with an overall average spiked recovery rate of 103.0%. The average concentration of the baseline iodine standard solution was determined to be 116.21 μg/L, and the relative error of the concentration determination with the addition of interfering substances was less than 5.0%. The comparison results showed that there was no statistically significant difference in the measurement results between the two methods ( t = - 0.06, P = 0.952). Conclusions:The method adopts automated detection, which is simple to operate, labor-saving, and does not require the use of arsenic trioxide. It has high precision and accuracy, and is suitable for detection of large quantities of samples.

Objective:To establish an arsenic free fully automatic online digestion iodine analyzer detection method for urinary iodine (hereinafter referred to as the method).Methods:Based on the principle of iodine catalyzed antimony cerium redox reaction, a fully automatic online digestion iodine analyzer was used to determine the iodine content in urine. The effectiveness of the method in terms of detection limit, precision, accuracy (determination of urinary iodine primary standard reference materials GBW09108z and GBW09110f and spiked recovery experiment), and interference experiments was validated. The method was compared with the arsenic cerium catalytic spectrophotometry method recommended by the National Reference Laboratory for Iodine Deficiency Disorders.Results:The linear range of the method was 0 - 300 μg/L, with a correlation coefficient │ r│> 0.999 5. The qualitative and quantitative detection limits were 7.41 and 18.01 μg/L, respectively. The relative standard deviation ( RSD) of urine samples with different iodine concentrations ranged from 1.0% to 1.7%. The results of the determination of iodine concentrations in urine using standard substances GBW09108z and GBW09110f were within the given standard range, with RSD < 2.5%. The range of spiked recovery rates for urine samples with different iodine concentrations was 101.3% to 104.8%, with an overall average spiked recovery rate of 103.0%. The average concentration of the baseline iodine standard solution was determined to be 116.21 μg/L, and the relative error of the concentration determination with the addition of interfering substances was less than 5.0%. The comparison results showed that there was no statistically significant difference in the measurement results between the two methods ( t = - 0.06, P = 0.952). Conclusions:The method adopts automated detection, which is simple to operate, labor-saving, and does not require the use of arsenic trioxide. It has high precision and accuracy, and is suitable for detection of large quantities of samples.

Objective:To study the application of antimony cerium catalytic spectrophotometry using a fully automatic biochemical analyzer (hereinafter referred to as this method) in the determination of water iodine.Methods:Based on the principle of antimony cerium reoxidation reduction reaction catalyzed by iodine, the iodine content in water was determined in the range of 0 - 100 μg/L iodine mass concentration. The detection limit, precision and accuracy (determination of standard substances GBW09113j and GBW09114j for iodine composition analysis in water and the experiment of standard recovery) of this method were verified. This method was compared with the arsenic and cerium catalytic spectrophotometry recommended by the National Reference Laboratory for Iodine Deficiency Disorders.Results:Within the range of 0 - 100 μg/L iodine mass concentration, the qualitative and quantitative detection limits of this method were 0.81 and 2.70 μg/L, respectively (sampling quantity was 35 μl). In the precision experiment, the relative standard deviation of water samples with different iodine mass concentrations ranged from 1.2% to 4.0%. The determination results of the standard substances GBW09113j and GBW09114j for iodine composition analysis in water were both within the given standard value range. The standard recovery rates of water samples with low, medium and high iodine mass concentrations ranged from 101.0% to 106.0%, and the total average standard recovery rate was 103.2%. The results of the method comparison experiment showed that there was no statistically significant difference in the results of water iodine determination between the two methods ( t = - 0.78, P = 0.779). Conclusion:This method has a low detection limit, high precision and good accuracy, making it suitable for the detection of large quantities of samples in the monitoring of iodine deficiency disorders.

Objective:To establish a hydride generation atomic fluorescence method using ammonium persulfate as the digestion reagent for determination of arsenic in urine (hereinafter referred to as this method).Methods:The collected urine samples with ammonium persulfate were heated and digested on the tubular electric heating automatic control constant temperature digester (60 holes), with 5% hydrochloric acid solution as reaction medium and current carrier and 1.5% potassium borohydride solution as reducing agent. Arsenic content was determined with a four-channel atomic fluorescence spectrometer. The arsenic standard solution of 0 - 10 μg/L was prepared to determine the standard curve of this method, and the method was evaluated from the detection limit, linear range, correlation coefficient, precision, standard addition recovery experiment, and urine arsenic quality control sample detection. The standard method "Determination of Arsenic in Urine by Hydride Generation Atomic Fluorescence Spectrometry" (WS/T 474-2015, referred to as the standard method) was used for comparison experiments.Results:When the sampling volume was 1 ml, the detection limit of this method (digest with 1 ml 1.5 mol/L ammonium persulfate) was 0.03 μg/L. In the range of arsenic content from 0 - 10 μg/L, the linear relationship between arsenic content and fluorescence intensity was good, and the correlation coefficients ( r) were all 0.999 9. The relative standard deviations( RSD) of the three replicates of urine samples with different concentrations were 1.00%, 0.89% and 0.49%, respectively. Urine arsenic quality control samples were tested, and the test results were all within the range of public values; the overall average recovery was 102.29%, and the recovery range was 92.10% - 108.15%. Compared with the standard method in the determination results of 20 urine samples, the difference was not statistically significant ( t = - 0.40, P > 0.05). Conclusions:The hydride generation atomic fluorescence spectrometry using ammonium persulfate as digestion reagent for the determination of arsenic in urine has the advantages of low detection limit, good precision, high accuracy, small amount of sampling and digestion reagent, simple operation, and less harmful gas generation in sample pretreatment. It is suitable for rapid determination of arsenic in urine in large quantities.

Gastric cancer is the most common gastrointestinal cancer in China. The morbidity and mortality are extremely high and there are significant challenges in the treatment of gastric cancer. Recent studies have shown that the expressions of T lymphocyte subsets vary in the immune microenvironment of gastric cancer patients. T lymphocytes are not only the main effector cells of human cellular immunity, but also the important immunoregulatory cells. T lymphocytes not only reflect the state of the tumor microenvironment, but also closely relate with the prognosis of patients. T lymphocytes play a crucial guiding role in the clinical treatment. Currently, clinical trials related to immunological checkpoint inhibitors are still underway, among which PD-1/PD-L1 monoclonal antibody has been approved for the treatment of gastric cancer. The applications of tumor vaccines and adoptive cell therapies in gastric cancer are also being explored. How to screen patients suitable to immunotherapy, develop the best combination therapy and evaluate the effectiveness of immunotherapy need to be studied and solved.

Gastric cancer is the most common gastrointestinal cancer in China. The morbidity and mortality are extremely high and there are significant challenges in the treatment of gastric cancer. Recent studies have shown that the expressions of T lymphocyte subsets vary in the immune microenvironment of gastric cancer patients. T lymphocytes are not only the main effector cells of human cellular immunity, but also the important immunoregulatory cells. T lymphocytes not only reflect the state of the tumor microenvironment, but also closely relate with the prognosis of patients. T lymphocytes play a crucial guiding role in the clinical treatment. Currently, clinical trials related to immunological checkpoint inhibitors are still underway, among which PD?1／PD?L1 monoclonal antibody has been approved for the treatment of gastric cancer. The applications of tumor vaccines and adoptive cell therapies in gastric cancer are also being explored. How to screen patients suitable to immunotherapy, develop the best combination therapy and evaluate the effectiveness of immunotherapy need to be studied and solved.

Gastric cancer is the most common gastrointestinal cancer in China. The morbidity and mortality are extremely high and there are significant challenges in the treatment of gastric cancer. Recent studies have shown that the expressions of T lymphocyte subsets vary in the immune microenvironment of gastric cancer patients. T lymphocytes are not only the main effector cells of human cellular immunity, but also the important immunoregulatory cells. T lymphocytes not only reflect the state of the tumor microenvironment, but also closely relate with the prognosis of patients. T lymphocytes play a crucial guiding role in the clinical treatment. Currently, clinical trials related to immunological checkpoint inhibitors are still underway, among which PD?1／PD?L1 monoclonal antibody has been approved for the treatment of gastric cancer. The applications of tumor vaccines and adoptive cell therapies in gastric cancer are also being explored. How to screen patients suitable to immunotherapy, develop the best combination therapy and evaluate the effectiveness of immunotherapy need to be studied and solved.