Background Work-related musculoskeletal disorders (WMSDs) are a major occupational health concern, particularly among workers exposed to adverse ergonomic conditions. Manganese production involves heavy physical demands, yet research on WMSDs among manganese workers remains limited. Objective To investigate the prevalence and influencing factors of WMSDs among manganese workers in a manganese enterprise in Guangxi. Methods A cross-sectional survey was conducted from May to June 2024 on workers at a manganese factory in Guangxi. The Chinese Musculoskeletal Disorders Questionnaire was used to collect information on demographic characteristics, distribution of musculoskeletal symptoms, and work-related exposures. χ² test was applied to compare differences in positive WMSDs rates across groups, and logistic regression analysis was performed to identify associated factors. Results A total of 1476 workers were enrolled in the study after pre-determined inclusion and exclusion criteria. The overall prevalence of WMSDs was 34.15%. The most commonly affected body regions were the lower back (17.28%), neck (16.67%), and shoulders (13.82%). The results of logistic regression analysis indicated that female, older age, and education level of college or above were associated with a higher risk of WMSDs (P<0.05). Awkward working postures were significantly associated with WMSDs in corresponding body regions; in particular, awkward postures of the neck, upper limbs, trunk, and lower limbs were related to an increased risk of WMSDs in multiple body sites (P<0.05). In addition, poor lighting conditions, high workplace temperature, frequent or sustained arm support during work, and high job demands were associated with an increased risk of overall or site-specific WMSDs (P<0.05). Conclusion The high prevalence of WMSDs among manganese workers is closely associated with demographic characteristics, working postures, and work environment and organizational factors. Targeted ergonomic interventions focusing on high-risk body regions and key ergonomic exposures are warranted to reduce the risk of WMSDs among manganese workers.

Objective:To explore the feasibility and efficacy of left ventricular decompression in pediatric patients supported by extracorporeal membrane oxygenation（ECMO）.Methods:The clinical data of 15 children who underwent left ventricular decompression during ECMO in the cardiac intensive care unit（CICU）of Guangzhou Women and Children's Medical Center from February 2021 to August 2023 were retrospectively analyzed.Results:Among the 15 patients，there were 8 males and 7 females,with a median age of 1.1 years old（20 days to 15 years old）and a median weight of 8.5（3.1 to 38.0）kg. Cardiac pathologies varied，including hypertrophic obstructive cardiomyopathy(1 case),left coronary artery abnormalities originating from the pulmonary artery（3 cases），aortic coarctation with ventricular septal defect（1 case），complete transposition of great arteries with ventricular septal defect（1 case），ventricular septal defect with severe mitral valve insufficiency（1 case），fulminant myocarditis（5 cases），tetralogy of Fallot（1 case），ascending aortic aneurysm with aortic valve insufficiency（1 case），and Kawasaki disease complicated with giant aneurysm（1 case）. The venous-arterial ECMO mode was used in all 15 children,9 cases were intubated centrally and 6 cases were intubated peripherally. The reasons for ECMO：low cardiac output（8 cases），cardiogenic shock（5 cases），and frequent ventricular tachycardia and ventricular fibrillation（2 cases）. Extracorporeal cardiopulmonary resuscitation was performed in 3 cases. The median duration of mechanical ventilation was 248 (142-590) h,the median CICU stay was 18 (7-26) d,and the median hospital stay was 28 (7-37) d. Of the 15 children,7 cases underwent emergency left ventricular decompression through a small sternal incision,with a mean decompression time of ECMO-assisted 12.2(9-22) h，and 8 cases underwent selective left ventricular decompression through a median sternal incision. Left ventricular systolic function improved significantly after decompression in all 15 patients，of whom 12 cases were successfully withdrew off ECMO and 10 cases of them survived.Conclusion:Left ventricular decompression can improve the cardiac dysfunction in children with ECMO，reduce the occurrence of complications，and increase the success rate and survival rate of ECMO.

Objective To analyze the risk factors of delayed wound recovery after Meek skin grafting in patients with extensive deep burn and its predictive efficiency.Methods A total of 100 patients with extensive deep burn who underwent Meek skin grafting from August 2018 to November 2024 were selected,and they were divided into the normal group(n=79)and the delayed group(n=21)according to the wound healing time.The clinical data of all patients were collected,and the influencing factors of delayed wound recovery after Meek skin grafting in patients with extensive deep burn were analyzed by Logistic regression model,and the efficiency of the model was analyzed by the receiver operating characteristic(ROC)curve and the Hosmer-Lemeshow goodness-of-fit test,respectively.Results There were statistically significant differences in the body mass index,hospitalization time,burn index,burn area,donor skin area,number of postoperative dressing change,postoperative nutritional support,postoperative pain scores,and hospitalized blood glucose levels between the two groups(P<0.05).Logistic regression analysis showed that high burn index(OR=1.086,β=0.082),large burn area(OR=1.155,β=0.144),fewer postoperative dressing change(OR=0.746,β=-0.293),lack of postoperative nutritional support(OR=6.439,β=1.862),high postoperative pain score(OR=4.483,β=1.500),and high level of hospitalized blood glucose(OR=2.251,β=0.811)were the influencing factors for delayed wound recovery after Meek skin grafting in patients with extensive deep burn(P<0.05).The ROC curve revealed that the combined prediction of the above six influencing factors for delayed postoperative wound recovery had an area under the ROC curve(AUC)of 0.896,with a sensitivity and specificity of 88.00%and 89.10%,respectively;and the Hosmer-Lemeshow test result showed:χ2=10.641,and P=0.223,indicating a high predictive efficacy and a certain calibration ability of the model.Conclusion The high burn index,large burn area,fewer postoperative dressing change,lack of postoperative nutritional support,high postoperative pain score and hospitalized blood glucose level were the influencing factors for delayed wound recovery after Meek skin grafting in patients with extensive deep burn,and the prediction model constructed by the above factors has good predictive ability,which can provide a reference for clinical treatment.

Objectives:To investigate the clinical outcomes of unilateral biportal endoscopy assisted unilateral laminotomy for bilateral decompression(ULBD)in the treatment of lumbar spinal stenosis under local anesthe-sia,and to compare the anesthetic effects of single-stage and two-stage local anesthesia.Methods:A retro-spective analysis was conducted on the data of 106 patients with lumbar spinal stenosis who underwent uni-lateral biportal endoscopy assisted ULBD treatment under local anesthesia in our hospital from January 2022 to June 2023.There were 51 males and 55 females,aged 55-83(66.7±14.5)years old,with the following le-sion segments:17 cases at L3-4,36 cases at L4-5,and 53 cases at L5-S1.Schizas classification:25 cases of grade B,36 cases of grade C,and 45 cases of grade D.Among them,52 patients underwent single-stage local anesthesia and were included in the single anesthesia group(Group A),while 54 patients received two-stage local anesthesia and were included in the two-stage local anesthesia group(Group B).There were no statistically significant differences in age,gender ratio,body mass index(BMI),surgical segments,Schizas classification and American Society of Anesthesiologists(ASA)classification between the two groups of patients.The perioperative complications,operative time,as well as the visual analogue scale(VAS)score,oxygen saturation,mean arterial pressure,heart rate in both groups before surgery(T1),during exposure(T2),during traction of the nerve root(T3),and immediately after surgery(T4)were recorded;The VAS scores for low back pain and leg pain,as well as the Oswestry disability index(ODI),were compared between the two groups before and after surgery.The MacNab assessment criteria were used to evaluate the overall postoperative efficacy of the patients at the final follow-up.Results:All patients successfully completed the operation.Two cases had dural tear,but no dural repair was performed;Five cases had mild headache,which disappeared after symptomatic treatment;Four cases had increased lower limb pain and numbness compared to pre-operative conditions,which were treated with symptomatic treatment for swelling reduction,and the symptoms alleviated or disappeared 3-5d after surgery;All incisions healed in stage Ⅰ.During the operation,the vital signs remained stable throughout and no unexpected incidents occurred.There was no statistical difference between group A and group B in operative time(101.9±17.3min vs.103.6±15.9min,P＞0.05).No statistically significant difference was observed in VAS scores,mean arterial pressure and heart rate between the two groups at T1 and T2(P＞0.05).At T3 and T4,the VAS scores,mean arterial pressure and heart rate of group A were significantly higher than those of group B(P＜0.05).At each time point after surgery,the VAS scores and ODI of the two groups improved significantly compared with those before surgery(P＜0.05),but there was no statistically significant difference between the two groups at the same time point(P＞0.05).At the final follow-up,31 cases in group A were excellent,14 cases were good,and 7 cases were fair,with an excellent and good rate of 86.5％;36 cases in group B were excellent,13 cases were good,and 5 cases were fair,with an excellent and good rate of 90.7％.There was no statistically significant difference in the excellent and good rate between the two groups(P＞0.05).Conclusions:The unilateral biportal endoscopy technique under local anesthesia for ULBD in the treatment of lumbar spinal canal stenosis can achieve good clinical efficacy,and two-stage local anesthesia provides a superior analgesic effect compared to single-stage local anesthesia.This method holds significant clinical application value,particularly for patients with lumbar spinal canal stenosis accompanied by complex comorbidities and at high risk for general anesthesia.

SPF chickens were immunized with HN-mRNA vaccine by intramuscular injection.He-magglutination inhibition(HI)test,lymphocyte proliferation test,RT-qPCR and pathological sec-tions were used to evaluate the humoral and cellular immunity and protection against challenge in-duced by the candidate HN-mRNA vaccine.The results showed that 2.5,5.0,and 7.5 μg HN-mR-NA induced HI antibody antibodies in a dose-dependent manner.Among them,the Hi antibody in-duced by 7.5 μg HN-mRNA was slightly higher than that of the weak toxic vaccine(La Sota strain).In addition,in response to the stimulation of inactivated NDV virus,the proliferation and activation of lymphocytes in 2.5,5.0 and 7.5 μg HN-mRNA immunization groups and commercial vaccine group were observed.To further evaluate the antiviral protection provided by HN mRNA immunization,the 105 ELD50 NDV strong strain NA-1 was used to attack the 7.5 μg HN-mRNA immunised group and the commercial weakened vaccine(La Sota strain)and PBS groups using na-sal and ocular drops.The results showed that the survival rate of 7.5 μg HN-mRNA immunization group and commercial vaccine group was 100％,and these vaccines could protect tissues and or-gans from the damage caused by virus infection.At the same time,7.5 μg HN-mRNA and commer-cial vaccine could shorten the time of virus shedding in vitro and the viral load in vivo.This study provides a foundational framework for the clinical application of NDV HN mRNA candidate vac-cines and offers insights for the development of novel mRNA vaccines for poultry.

Objective To analyze the risk factors of delayed wound recovery after Meek skin grafting in patients with extensive deep burn and its predictive efficiency.Methods A total of 100 patients with extensive deep burn who underwent Meek skin grafting from August 2018 to November 2024 were selected,and they were divided into the normal group(n=79)and the delayed group(n=21)according to the wound healing time.The clinical data of all patients were collected,and the influencing factors of delayed wound recovery after Meek skin grafting in patients with extensive deep burn were analyzed by Logistic regression model,and the efficiency of the model was analyzed by the receiver operating characteristic(ROC)curve and the Hosmer-Lemeshow goodness-of-fit test,respectively.Results There were statistically significant differences in the body mass index,hospitalization time,burn index,burn area,donor skin area,number of postoperative dressing change,postoperative nutritional support,postoperative pain scores,and hospitalized blood glucose levels between the two groups(P<0.05).Logistic regression analysis showed that high burn index(OR=1.086,β=0.082),large burn area(OR=1.155,β=0.144),fewer postoperative dressing change(OR=0.746,β=-0.293),lack of postoperative nutritional support(OR=6.439,β=1.862),high postoperative pain score(OR=4.483,β=1.500),and high level of hospitalized blood glucose(OR=2.251,β=0.811)were the influencing factors for delayed wound recovery after Meek skin grafting in patients with extensive deep burn(P<0.05).The ROC curve revealed that the combined prediction of the above six influencing factors for delayed postoperative wound recovery had an area under the ROC curve(AUC)of 0.896,with a sensitivity and specificity of 88.00%and 89.10%,respectively;and the Hosmer-Lemeshow test result showed:χ2=10.641,and P=0.223,indicating a high predictive efficacy and a certain calibration ability of the model.Conclusion The high burn index,large burn area,fewer postoperative dressing change,lack of postoperative nutritional support,high postoperative pain score and hospitalized blood glucose level were the influencing factors for delayed wound recovery after Meek skin grafting in patients with extensive deep burn,and the prediction model constructed by the above factors has good predictive ability,which can provide a reference for clinical treatment.

BACKGROUND:Cervical instability is a common orthopedic disease in young and middle-aged people,and is the early manifestation of cervical spondylosis,which has a great impact on the quality of life of patients.Therefore,early diagnosis of cervical instability to implement early intervention has positive clinical and social significance.OBJECTIVE:The clinical prediction model of cervical instability in young and middle-aged people was constructed based on machine learning to realize early screening of cervical instability in young and middle-aged people before X-ray examination.METHODS:From September 2022 to October 2023,155 young and middle-aged adults with cervical instability and 88 with non-cervical instability recruited through recruitment advertisements and spinal department outpatient of Wangjing Hospital,China Academy of Chinese Medical Sciences were selected as research subjects.The research subjects'general information,living and working habits,discomfort symptoms,visual analog scale score,Neck Disability Index,and 36-ltem Short Form Health Survey were collected on site based on questionnaires.The above information was used as predictive factors.After screening,six machine learning algorithms of Support Vector Machine,LightGBM,RandomForest,Logistic,AdaBoost,and XGBClassifier were used to train the model by ten-fold cross-validation method,and the clinical prediction model of cervical instability was constructed.Area under the curve was used as the main evaluation index.Univariate analysis was performed on the predictors,and SHAP method was used to rank the importance of the predictors.Correlation heat maps were used to show the degree of linear correlation between the predictors and the cervical instability.RESULTS AND CONCLUSION:(1)Among the six machine learning models,RandomForest model was chosen as the final prediction model,including nine predictors,such as age,body mass index,neck circumference/neck length,visual analog scale score,Neck Disability Index,bodily pain,general health,vitality,and mental health,area under the curve=0.725 4,and the calibration degree was good.It could be used as a reference tool for early screening of cervical instability in young and middle-aged people.(2)There were significant differences in age,visual analog scale score,Neck Disability Index,bodily pain,general health,and vitality between the two groups(P＜0.05).(3)The order of importance of predictors was age,Neck Disability Index,visual analog scale score,general health,body mass index,vitality,bodily pain,neck circumference/neck length,mental health,among which age,visual analog scale score,Neck Disability Index were positively correlated with cervical instability,while general health,body mass index,vitality,bodily pain,neck circumference/neck length,and mental health were negatively correlated with cervical instability.

Objective To explore the impact of suture configuration and fixation type on the biome-chanical strength of rotator cuff repair,using a factorial design study.Methods Sixteen fresh-frozen porcine shoulder samples were randomized into an anchorless double-row suture bridge transosseous su-tures(DS)group,an anchored double-row suture bridge transosseous-equivalent(DE)group,an an-chorless X-BOX construct transosseous sutures(XS)group,and an anchored X-BOX construct transos-seous-equivalent(XE)group,each of four,according to suture configuration(double-row suture bridge,traditional X-BOX construct)and fixation type(suture anchors,transosseous sutures).Then,their fatigue resistance(first-cycle excursion,gap length difference ratio,and the percentage of ex-posed footprints)and the failure strength(the maximum failure load and the re-tear type)were mea-sured using a biomechanical material testing machine.Results Different suture configurations affected failure strength(F=39.559,P<0.001),with the double-row suture bridge groups(693.07±58.35 N,746.76±138.57 N)showing significantly higher failure strength,compared to the traditional X-BOX groups(462.90±18.91 N,421.43±90.76 N).However,the fixation type did not significantly im-pact failure strength(F=1.161,P=0.302).Moreover,the suture configuration influenced the gap differ-ence ratio(F=7.781,P=0.016),but had no significant correlation with other fatigue resistance indica-tors(P>0.05).Meanwhile,failure strength and fatigue resistance were not correlated with fixation type,and the interaction between suture and fixation type(P>0.05).The incidence of failure types for the four suture configurations was as follows:Type I tendon tear:XS>XE>DS=DE;type II tendon tear:DS>XE>XS=DE;fixing material-related failure:DE>DS=XE=XS.Conclusion The failure strength and gap formation ratio in rotator cuff repair under fatigue loading are influenced by suture configuration,whereas no significant association has been observed with respect to fixation method,whether using transosseous sutures or suture anchors.

Objective To systematically evaluate the radiation impact of radioactive sources used in online elemental analyzers in cement enterprises on the surrounding environment, and to provide a scientific basis for radiation monitoring and safety management at the application sites of this type of radioactive sources. Methods A statistical analysis was conducted on 15 cement enterprises in Guangxi Province using online elemental analyzers with ²⁵²Cf as the radioactive source. On-site investigation of radiation safety management and on-site monitoring of radiation environment were performed, followed by an evaluation based on the collected data. Results Although the gamma radiation ambient dose equivalent rate and neutron ambient dose equivalent rate increased around the sites using online elemental analyzers with ²⁵²Cf as the radioactive source, they all met the requirements of the Radiological Health Protection Requirements for Instruments with Sealed Sources (GBZ 125—2009). Conclusion Under the current usage and management conditions, the application of this type of radioactive sources has controllable radiation impact on the surrounding environment, and will not pose a threat to public health and environmental safety. However, continuous strengthening of radiation safety management measures and regular radiation monitoring work are still needed to ensure the safe use of radioactive sources, further reducing potential radiation risks and providing strong guarantees for the safe application of radioactive sources in online elemental analyzers in cement enterprises.

Objective: To explore the potential category patterns of risk prevention and control behaviors of HIV infection among young students who have sex with men (MSM) and their impact on HIV infection and late detection, aiming to optimize intervention strategies. Methods: From September 2017 to December 2024, a total of 1 637 MSM young students in Tianjin were recruited through both online and offline channels. Latent class analysis was applied to classify 11 HIV risk prevention and control behaviors [condom use during the most recent anal sex in the past 6 months, consistent condom use, use of water based lubricants, abstinence from recreational drugs, regular on site professional testing, fixed sexual partners, partner testing, awareness of partner s HIV testing results, testing before sexual activity, nucleic acid testing, and use of pre exposure prophylaxis (PrEP) or post exposure prophylaxis (PEP)]. Multivariate Logistic regression analyzed associations between demographic characteristics/intervention services factors and latent classes. Differences in HIV infection and late detection across behavior patterns were compared. Results: HIV risk prevention and control behaviors among MSM students were classified into three latent classes:condom dependent group (38.42%), low prevention group (27.73%), and comprehensive prevention group (33.85%). Students who received condom promotion/testing services were more likely to belong to the comprehensive prevention group ( OR =5.58), while those who received peer education were less likely to the comprehensive prevention group ( OR =0.43) (both P <0.01). Among the MSM student population, the HIV infection rate was 4.83%, with 2.26% of cases detected late. The HIV infection rate (1.45%) and late detection proportion (0.82%) in the comprehensive prevention group were lower than those in the low prevention group (7.89% and 3.83%, respectively) ( χ 2=16.20, 7.31, both P <0.01). Conclusions HIV risk prevention and control behaviors among MSM young students exhibit significant heterogeneity. Comprehensive prevention strategies can effectively reduce HIV infection and late detection risks. It is necessary to optimize peer education content and improve the accessibility of diversified prevention measures such as PrEP/PEP to enhance HIV prevention and control.