In this study,an ON/OFF type micro-valve with a sandwich(glass-silicon-glass)structure was designed and fabricated based on the micro-electro-mechanical system(MEMS)technique.The deformable membrane of this micro-valve was prepared on the silicon on insulator(SOI)substrate and sealed using Si-Si bonding and anodic bonding methods.The micro-valve had high-temperature stability and was suitable for integration with other gas chromatography components.The deformable membrane with a thickness of 10 μm was processed on the top silicon of the SOI substrate.The flow control of the micro-valve could be achieved by changing the driving pressure applied to the deformable membrane to deform it.Compared with polymer membranes,the deformable membrane prepared on the top layer silicon of SOI had better temperature stability and could be released using the deep reactive ion etching technique after silicon-silicon bonding,avoiding deformation during the preparation process.In addition,due to the small gap between the membrane and the inlet/outlet holes,the dead volume of the microvalve was very small.The test results indicated that the micro-valve achieved flow control and ON/OFF functions with good repeatability.

A monolithic integrated gas chromatography chip,consisting of a micro gas chromatography column(μGCC)and a micro helium discharge ionization detector(μHDID)was proposed.The chip was fabricated using micro electromechanical system(MEMS)technique,and its sensitivity was improved from two aspects.On one hand,open tubular column was selected as the separation device,and the auxiliary helium channel width of μHDID was modulated based on the microchannel width of the μGCC to match the flow rates of μHDID and μGCC.On the other hand,the electrode structure inside the μHDID collection zone was optimized,a bias electrode group around the collection electrode was constructed,and the ion collection efficiency was improved.After coating HKUST-1 as the stationary phase,the monolithic integrated gas chromatography chip could achieve baseline separation and detection of light hydrocarbon gas mixture(methane,ethane,propane,andn-butane),with a detection limit for propane as low as 25 pg.The chip could carried out test under temperature-programmed conditions,with a resolution of 9.24 for ethane and propane.

A micro gas chromatographic column with mesoporous surface micro column array prepared by anodization method was proposed.A porous support layer with a characteristic pore size of about 30 nm inside the chromatographic column was prepared in situ using anodization method,and a uniform alumina stationary phase was deposited on the mesoporous support layer using atom layer deposition(ALD)technique.The existence of a mesoporous support layer increased surface area of the chromatographic column,thereby increasing the total amount of stationary phase loading and enhancing column capacity,which facilitated chromatographic separation.The test results showed that the porous support layer significantly reduced the longitudinal molecular diffusion and mass transfer resistance of the micro gas chromatographic column,and significantly increased the number of theoretical plates(n-nonane increased by 290.2%).Furthermore,column efficiency of the chromatographic column was less affected by flow rate,which was conducive to rapid separation of heavy hydrocarbon mixtures.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

Objective:This study investigated the independent risk factors for lymph node metastasis（LNM）in high-risk prostate cancer（HRPCa）patients undergoing robot-assisted radical prostatectomy（RARP），and constructed a nomogram model based on clinical data to improve the accuracy and clinical practicality of preoperative prediction of LNM.Methods:A retrospective analysis was conducted on the clinical data of 218 HRPCa patients who received RARP treatment at the First Medical Center of the PLA General Hospital from January 2020 to March 2025 as the modeling group. The age of the modeling group was（66.91±6.94）years old. 75 cases（34.40%）had a history of smoking，and 48 cases（22.02%）had a history of drinking. There were a body mass index（BMI）of 25.55（23.58，27.00）kg/m 2，a total prostate-specific antigen（tPSA）of 20.59（10.42，30.61）ng/ml，a free prostate-specific antigen（fPSA）of 1.87（1.04，3.26）ng/ml，a prostate volume（PV）of（41.19±21.00）ml，a prostate-specific antigen density（PSAD）of 0.52（0.30，0.84）ng/ml 2. Among the patients，60 cases（27.52%）had a preoperative biopsy Gleason score >8，and the percentage of positive biopsy cores（PPBC）was 50%（31%，80%）. Thirty-one patients（14.22%）were staged clinically as >T 2c. The diagnostic criteria for high-risk prostate cancer（HRPCa）were defined as meeting any one of the following：PSA >20 ng/ml，Gleason score on prostate biopsy ≥8，or clinical stage ≥T 3. Among the 218 patients in the modeling cohort，67 cases（30.73%）met two of the criteria，and 7 cases（3.21%）met all three criteria. All 218 patients underwent RARP，and based on postoperative pathology，they were divided into the LNM group and the non-LNM group. The relationship between the number of diagnostic criteria met and the occurrence of LNM was analyzed. An external validation cohort included 42 HRPCa patients who underwent RARP at the Third，Fifth Medical Centers of the PLA General Hospital between January 2023 and May 2025. Their mean age was（66.79±5.92）years. Eighteen patients（42.86%）had a smoking history，and nine（21.43%）had a history of alcohol consumption. The median BMI was 26.00（23.80，27.13）kg/m 2. The median tPSA level was 17.34（8.97，27.30）ng/ml. The median fPSA was 1.51（0.83，2.52）ng/ml，and the median PV was（35.57 ± 15.25）ml. The median PSAD was 0.57（0.23，0.87）ng/ml 2，and the median PPBC was 58%（36%，71%）. Three patients（7.14%）had a clinical stage >T 2c，and 12 patients（28.57%）had a Gleason score >8 on preoperative biopsy. Univariate and multivariate binary logistic regression analyses were used to identify independent risk factors for LNM，and a nomogram model was constructed based on these factors. The predictive performance of the model was evaluated using receiver operating characteristic（ROC）curves and calibration plots，and the model was validated in the external cohort. Result:According to postoperative pathology，45 patients were classified into the LNM group，and 173 into the non-LNM group. The probability of LNM increased proportionally with the number of diagnostic criteria met for HRPCa（meeting two criteria： OR = 4.762，95% CI 2.323-9.761， P < 0.01；meeting three criteria： OR = 10.667，95% CI 2.187-52.025， P=0.003）. Binary logistic regression analysis revealed that age（ OR=0.913，95% CI 0.859-0.971， P = 0.004），tPSA（ OR=1.039，95% CI 1.018-1.061， P<0.01），PPBC（ OR = 5.656，95% CI 1.101-29.056， P = 0.038），and clinical T stage（T 2c stage： OR=2.945，95% CI 0.888-9.769， P=0.077；>T 2c stage OR = 18.351，95% CI 4.790-70.306， P < 0.01）were independent risk factors for postoperative LNM in HRPCa patients after RARP. The ROC curve of the nomogram model based on these factors showed an area under the curve（AUC）of 0.853（95% CI 0.790-0.917）. In the external validation cohort，the nomogram achieved an AUC of 0.743（95% CI 0.556-0.929）. The calibration plots demonstrated good agreement between the predicted probabilities and actual observations. Conclusions:Age，tPSA，PPBC，and clinical T stage were independent predictors of postoperative LNM in HRPCa patients undergoing RARP. The greater the number of HRPCa diagnostic criteria met，the higher the likelihood of postoperative LNM. The nomogram developed in this study could effectively predict the risk of LNM in HRPCa patients after RARP.

The scaphoid bone is one of the important bone of hand,which is frequently injured and difficult to treat in clinical practice.Therefore,it is very important to deeply study the microstructure and biomechanical characteristics of the scaphoid bone for understanding its injury mechanism and optimizing treatment scheme.Microcomputed tomography(micro-CT)provides high-resolution imaging of bone tissue,while finite element analysis can help to simulate the stress distribution and behavioral patterns of the scaphoid bone under various physiological and pathological states.The high-resolution three-dimensional image of the scaphoid bone obtained by micro-CT technology can be used to construct finite element models of real anatomical structure of the scaphoid bone,thus achieving accurate simulation of the mechanical properties of the scaphoid bone.The fusion of these two advanced technologies provides a new perspective for revealing the structural and functional relationships and injury mechanism of the scaphoid bone.Therefore,this paper reviews the anatomical characteristics of the scaphoid bone and its biomechanical behavior in different states,emphasizing the specific applications and advantages of micro-CT and finite element analysis techniques in the study of the scaphoid bone.By summarizing the research findings in recent years,this paper provides novel scientific basis and methods for the diagnosis,treatment,and prevention of scaphoid bone-related disorders.

Objective To study the effect of auditory and speech development after cochlear implant(CI)in children with bilateral cochlear nerve deficiency(CND)and its influencing factors.Methods A total of 20 children with bilateral CND were included in the study,of which 5 were implanted bilaterally and 15 unilaterally.CT of the temporal bone showed stenosis of the cochlear aperture in 14 cases and atresia of the cochlear aperture in 6 cases.There were 8 cases accompanied by other inner ear malformations,and 12 cases with no accompanying inner ear mal-formations.MRI of the internal auditory canal showed 1 nerve in 5 cases,2 nerves in 6 cases,3 nerves in 8 cases,and 4 nerves in 1 case.There were 6 cases in which the EABR was not elicited and 14 cases in which it was elicited.The postoperative auditory and speech abilities of the subjects were evaluated using categories of auditory perform-ance(CAP)and speech intelligibility rating(SIR).Results ① The CAP(P＜0.001)and SIR(P＜0.001)scores of the children with stenosis of the cochlea nerve canal were higher than those of the patients with atresia of the cochlea nerve canal.② The more nerve roots in the internal auditory canal,the higher the score of CAP(P=0.003)and SIR(P=0.008).③ CAP score of the children with EABR elicited was higher than that of the children without EABR elicited(P=0.030).The difference in SIR scores was not statistically significant(P=0.14).④The differences in CAP and SIR between those with bilateral CI and unilateral CI,as well as between those with and without other inner ear malformations,were not statistically significant(P＞0.05).Conclusion Children with bi-lateral CND had significant postoperative improvement in auditory function but poor speech development after CI.Postoperative auditory speech ability was related to the condition of the cochlear foramen,the number of nerve roots in the internal auditory canal,and whether or not the EABR was elicited intraoperatively.

Objective:This study investigated the independent risk factors for lymph node metastasis（LNM）in high-risk prostate cancer（HRPCa）patients undergoing robot-assisted radical prostatectomy（RARP），and constructed a nomogram model based on clinical data to improve the accuracy and clinical practicality of preoperative prediction of LNM.Methods:A retrospective analysis was conducted on the clinical data of 218 HRPCa patients who received RARP treatment at the First Medical Center of the PLA General Hospital from January 2020 to March 2025 as the modeling group. The age of the modeling group was（66.91±6.94）years old. 75 cases（34.40%）had a history of smoking，and 48 cases（22.02%）had a history of drinking. There were a body mass index（BMI）of 25.55（23.58，27.00）kg/m 2，a total prostate-specific antigen（tPSA）of 20.59（10.42，30.61）ng/ml，a free prostate-specific antigen（fPSA）of 1.87（1.04，3.26）ng/ml，a prostate volume（PV）of（41.19±21.00）ml，a prostate-specific antigen density（PSAD）of 0.52（0.30，0.84）ng/ml 2. Among the patients，60 cases（27.52%）had a preoperative biopsy Gleason score >8，and the percentage of positive biopsy cores（PPBC）was 50%（31%，80%）. Thirty-one patients（14.22%）were staged clinically as >T 2c. The diagnostic criteria for high-risk prostate cancer（HRPCa）were defined as meeting any one of the following：PSA >20 ng/ml，Gleason score on prostate biopsy ≥8，or clinical stage ≥T 3. Among the 218 patients in the modeling cohort，67 cases（30.73%）met two of the criteria，and 7 cases（3.21%）met all three criteria. All 218 patients underwent RARP，and based on postoperative pathology，they were divided into the LNM group and the non-LNM group. The relationship between the number of diagnostic criteria met and the occurrence of LNM was analyzed. An external validation cohort included 42 HRPCa patients who underwent RARP at the Third，Fifth Medical Centers of the PLA General Hospital between January 2023 and May 2025. Their mean age was（66.79±5.92）years. Eighteen patients（42.86%）had a smoking history，and nine（21.43%）had a history of alcohol consumption. The median BMI was 26.00（23.80，27.13）kg/m 2. The median tPSA level was 17.34（8.97，27.30）ng/ml. The median fPSA was 1.51（0.83，2.52）ng/ml，and the median PV was（35.57 ± 15.25）ml. The median PSAD was 0.57（0.23，0.87）ng/ml 2，and the median PPBC was 58%（36%，71%）. Three patients（7.14%）had a clinical stage >T 2c，and 12 patients（28.57%）had a Gleason score >8 on preoperative biopsy. Univariate and multivariate binary logistic regression analyses were used to identify independent risk factors for LNM，and a nomogram model was constructed based on these factors. The predictive performance of the model was evaluated using receiver operating characteristic（ROC）curves and calibration plots，and the model was validated in the external cohort. Result:According to postoperative pathology，45 patients were classified into the LNM group，and 173 into the non-LNM group. The probability of LNM increased proportionally with the number of diagnostic criteria met for HRPCa（meeting two criteria： OR = 4.762，95% CI 2.323-9.761， P < 0.01；meeting three criteria： OR = 10.667，95% CI 2.187-52.025， P=0.003）. Binary logistic regression analysis revealed that age（ OR=0.913，95% CI 0.859-0.971， P = 0.004），tPSA（ OR=1.039，95% CI 1.018-1.061， P<0.01），PPBC（ OR = 5.656，95% CI 1.101-29.056， P = 0.038），and clinical T stage（T 2c stage： OR=2.945，95% CI 0.888-9.769， P=0.077；>T 2c stage OR = 18.351，95% CI 4.790-70.306， P < 0.01）were independent risk factors for postoperative LNM in HRPCa patients after RARP. The ROC curve of the nomogram model based on these factors showed an area under the curve（AUC）of 0.853（95% CI 0.790-0.917）. In the external validation cohort，the nomogram achieved an AUC of 0.743（95% CI 0.556-0.929）. The calibration plots demonstrated good agreement between the predicted probabilities and actual observations. Conclusions:Age，tPSA，PPBC，and clinical T stage were independent predictors of postoperative LNM in HRPCa patients undergoing RARP. The greater the number of HRPCa diagnostic criteria met，the higher the likelihood of postoperative LNM. The nomogram developed in this study could effectively predict the risk of LNM in HRPCa patients after RARP.