Objective To understand mosquito density, species composition, and seasonal variations around the Beijing Capital International Airport(BCIA)and provide scientific evidence for mosquito-borne disease prevention and control. Methods Meteorological data were collected from 2016 to 2022, and mosquito density was monitored at seven surveillance sites around the BCIA from May to October each year using CO2-baited mosquito traps to analyze the relationship between mosquito density and meteorological factors. Results In total,68 518 female mosquitoes were captured, with a mosquito density of 10.20 per light · hour. The dominant species was Culex pipiens pallens(73.90%), followed by Aedes albopictus(9.71%)and Ae. vexans(9.29%);the mosquito density was highest in 2016(14.8 per light·hour)and lowest in 2022(4.46 per light·hour). Significant statistical differences were observed in mosquito density among different species(F=18.118, P<0.05). The density of Cx. pipiens pallens and other mosquito species showed a mutually exclusive trend; the peak of mosquito density varied based on years and habitats, with significant statistical differences in mosquito density among different habitats(F=8.504, P<0.05). The highest mosquito density was observed near the Wenyu River(21.50 per light·hour), whereas the lowest was recorded at the BCIA construction site(2.44 per light· hour). The monthly average temperature(r=0.595), monthly average highest temperature(r=0.575), and monthly average lowest temperature(r=0.624)showed moderate positive correlations, whereas the monthly average air pressure(r=-0.484)showed a moderate negative correlation. The monthly average minimum temperature was included in the regression model(F=25.575, P<0.000), and the equation Y=1.029X4-8.181 was used. The monthly average air pressure 2 months prior(b=-2.418, β=-1.619, P<0.05)and the monthly average relative humidity(b=-0.739, β=-1.201, P<0.05)significantly negatively predicted the mosquito density. Notably, the regression equation used was y=2526.170+(-2.418)X9+(-0.739)X13. The exposure-response analysis revealed that the density of mosquitoes was not linearly related to the average monthly air pressure, rainfall, and duration of sunshine. Conclusions The dominant mosquito species around the BCIA was Cx. pipiens pallens, Ae. albopictus, and Ae. vexans. During the control of Cx. pipiens pallens, the impact on other mosquito species must also be considered. Environmental management, breeding sites, and scientific use of pesticides should be prioritized based on the activity periods of mosquitoes. Further studies on mosquitoes and meteorological factors should be conducted to provide references and novel avenues for mosquito control.

Objective To investigate the effect of different decompression methods on the efficacy of the unilateral biportal endoscopy(UBE)in the treatment of severe lumbar spinal stenosis(LSS).Methods A total of 203 elderly patients with LSS who underwent UBE treatment in our hospital from September 2021 to June 2024 were selected and divided into the unilateral group(102 cases)and the bilateral group(101 cases)according to different decompression methods.The unilateral group underwent unilateral decompression during operation,while the bilateral group underwent bilateral decompression(with bilateral decompression through the same incision and unilateral approach)during operation.The perioperative conditions,anatomical image parameters,visual analogue scale(VAS)scores,Oswestry disability index(ODI),and complications were compared between the two groups.The rehabilitation progress and complications of patients with different Charlson comorbidity index(CCI)values were compared.Results The operation time of patients in the bilateral group was longer than that in the unilateral group(P<0.05).The dural sac area and lumbar spinal canal area of patients in the bilateral group were larger than those in the unilateral group immediately after operation and 3 months after operation(P<0.05).The VAS scores and ODI 7 days and 3 months after operation of patients in the bilateral group were lower than those in the unilateral group(P<0.05).There was no statistically significant difference in the total incidence of complications between the two groups of patients(P>0.05).The first time of getting out of bed after operation and hospital stay in patients with CCI value>2 scores were longer than those in patients with CCI value≤2 scores(P<0.05).Conclusion Compared with unilateral decompression,bilateral decompression for elderly patients with severe LSS takes a longer surgical time,but it can better restore lumbar shape,alleviate pain,improve lumbar function,and has higher safety,and the milder the patient's condition,the faster the postoperative recovery.

Objective To develop a novel protective ventilator circuit component and to verify its performance by water seal and anti-splash experiments.Methods A novel protective ventilator circuit component had a design scheme with the multifunctional joint,and consisted of a tee connection tube,an isolation sleeve and a stop sleeve,of which,the tee connection tube was made of polyethylene polymer material and the others were made of silicone material.The tee connection tube had a T-shaped structure with two standard connection ports,which was composed of an adapter,a sealing cap,a plug and a sealing ring;the isolation sleeve was in the shape of a cylinder with a raised bottom,which was inserted into the adapter;the stop sleeve was located in the isolation sleeve,with an inverted frustum of a cone at the bottom and a rounded hole in the middle of the inverted frustum.An open ventilator circuit tube was involved in the performance verification of the circuit component developed.In the water seal experiment,sputum aspiration was simulated and the heights of the liquid level drop in the L-shaped tubes were compared after sputum aspiration.In the anti-splash experiment,the infection rates on the surfaces of the sterile hole towels and gloves were calculated.Results Water seal experiment showed after sputum aspiration the open ventilator circuit tube had the liquid level at the L-shaped tube higher significantly than that of the circuit component;the anti-splash experiment indicated sputum aspiration resulted in the occurance of the splashing out of the secretion and 77.5%infection rate by the open ventilator circuit tube,while no splashing out and 0%infection rate by the circuit component developed.Conclusion The novel protective ventilator circuit component behaves well in sealing and anti-splashing,and thus is worthy of clinical application for sputum aspiration.[Chinese Medical Equipment Journal,2025,46(4):113-117]

Objective To compare the differences in dosimetry and treatment efficiency of three radiotherapy plans after left-sided breast-conserving surgery,including modified intensity-modulated radiation therapy(IMRT),cross-field volume-modulated arc therapy(VMAT)or improved VMAT,so as to provide references for clinical practice.Methods Three radiotherapy plans of modified IMRT,cross-field VMAT and improved VMAT were designed for 12 patients after left-sided-breast-conserving surgery.The modified IMRT with five irradiation fields and the improved VMAT with two arcs were modified by not setting cross-fields while determining the start and end angles with the rays passing through the least lung area.The cross-field VMAT had its start and end angles set based on the cross-fields.The doses to the target areas,peripheral organs at risk,heart and its substructures were evaluated,and dose verification was carried out.The three plans were compared in terms of treatment efficiency and gamma pass rate.SPSS 22.0 was used for statistical analysis.Results All the three plans behaved well in dose distribution.In terms of planning gross tumor volume dosimetry dosimetry,the improved VMAT and modified IMRT gained advantages than others in CI and D50,respectively,with the differences being significant(all P<0.05).In terms of planning target volume dosimetry,the modified IMRT had the V107 and D50 lower than those of the others,with the differences being significant(P<0.05).In terms of the protection of peripheral organs at risk,V5 of the left lung,Dmean of the right lung and Dmean of the healthy breast were lower in the modified IMRT plan than in the other 2 plans,with statistically significant differences(P<0.05);V20,V30,V35 and V40 of the left lung were lower in the modified VMAT plan than in the other 2 plans,with statistically significant differences(P<0.05).In terms of protection of heart and its substructures,the left ventricle V20,V30 and Dmean of the improved VMAT plan behaved better than those of other 2 plans,and the difference was statistically significant(all P<0.05).In terms of treatment efficiency,the cross-field VMAT plan had the lowest MU while highest treatment efficiency;the improved VMAT plan had the MU higher while the treatment efficiency lower than the cross-field VMAT plan;the modified IMRT plan had the highest MU while the lowest gamma pass rate,and the differences in the MUs and gamma pass rates among the three plans were statistically significant(P<0.05).Conclusion Under the same standard conditions,the cross-field VMAT and improved VMAT plans show technical advantages.Though the improved VMAT plan has the treatment efficiency lower than the cross-field VMAT,it decreases the possibility of radiocardiac injury in terms of dosimetry and thus can be used for radiotherapy after left-sided breast-conserving surgery.[Chinese Medical Equipment Journal,2025,46(4):45-51]

Objective:To construct a rat model of non-alcoholic fatty liver disease(NAFLD)by choline-deficient high fat diet(CDHFD),and to observe the association between feeding cycle and antioxidant pathway.Methods:The study lasted 16 weeks and was divided into 4 cycles.Detection of pathological changes and expression of antioxidant enzymes in rats liver in different cycles.Results:The early stage of liver steatosis and inflammation in model rats was 2～4 weeks,non-alcoholic steatohepatitis(NASH)stage was 4～8 weeks,and liver fibrosis progression was 8～16 weeks.Mechanistic studies had shown that the expressions of antioxidant enzymes Nrf2,SOD and GSH-Px in the liver of NAFLD rats gradually decreased with the extension of the feeding cycle.Conclusion:Different modeling cycles can successfully induce the pathological changes of steatosis,inflammation and liver fibrosis in rat liver,and the pathological changes are time-dependent with the expressions of antioxidant enzymes.

Aim To investigate the effects of the fangchinoline derivative LYY-32 on the biological prop-erties of the BLM642-1290 DNA helicase,in order to lay a foundation for further research on its antitumor activity.Methods Fluorescence polarization assay,malachite green-phosphate and ammonium molybdate colorime-try,and fluorescein-labeled DNA gel electrophoresis experiments were conducted to study the effects of fangchinoline derivative LYY-32 on the DNA binding activity,ATPase activity,and DNA unwinding activity of BLM642-1290 DNA helicase.The effects of LYY-32 on the DNA unwinding activity of DNA helicase in cells were studied using fluorescent techniques and time-lapse microscopy.Ultraviolet spectral scanning was used to investigate the effects of LYY-32 on the confor-mation of the BLM642-1290 DNA helicase.Results At a concentration of 10 μmol·L-1,the inhibition rate of LYY-32 on BLM642-1290 DNA helicase binding to dsDNA was 53.17％.At a concentration of 5 μmol·L-1,the inhibition rate of LYY-32 on BLM642-1290 DNA helicase binding to ssDNA was 88.49％.The inhibition rate of LYY-32 on the ATPase activity of BLM642-1290 DNA he-licase was 89.3％at a concentration of 50 μmol·L-1.When the concentration of LYY-32 exceeded 5μmol·L-1,its inhibition rate on the DNA unwinding activity of BLM642-1290 DNA helicase was 100％.LYY-32 also significantly inhibited the DNA unwinding ac-tivity of DNA helicase in cells.However,LYY-32 had no effect on the conformation of BLM642-1290 DNA heli-case.Conclusion The DNA binding activity,AT-Pase activity,and DNA unwinding activity of BLM642-1290 DNA helicase could be significantly inhibi-ted by the fangchinoline derivative LYY-32.

Aim To investigate the effects of the fangchinoline derivative LYY-32 on the biological prop-erties of the BLM642-1290 DNA helicase,in order to lay a foundation for further research on its antitumor activity.Methods Fluorescence polarization assay,malachite green-phosphate and ammonium molybdate colorime-try,and fluorescein-labeled DNA gel electrophoresis experiments were conducted to study the effects of fangchinoline derivative LYY-32 on the DNA binding activity,ATPase activity,and DNA unwinding activity of BLM642-1290 DNA helicase.The effects of LYY-32 on the DNA unwinding activity of DNA helicase in cells were studied using fluorescent techniques and time-lapse microscopy.Ultraviolet spectral scanning was used to investigate the effects of LYY-32 on the confor-mation of the BLM642-1290 DNA helicase.Results At a concentration of 10 μmol·L-1,the inhibition rate of LYY-32 on BLM642-1290 DNA helicase binding to dsDNA was 53.17％.At a concentration of 5 μmol·L-1,the inhibition rate of LYY-32 on BLM642-1290 DNA helicase binding to ssDNA was 88.49％.The inhibition rate of LYY-32 on the ATPase activity of BLM642-1290 DNA he-licase was 89.3％at a concentration of 50 μmol·L-1.When the concentration of LYY-32 exceeded 5μmol·L-1,its inhibition rate on the DNA unwinding activity of BLM642-1290 DNA helicase was 100％.LYY-32 also significantly inhibited the DNA unwinding ac-tivity of DNA helicase in cells.However,LYY-32 had no effect on the conformation of BLM642-1290 DNA heli-case.Conclusion The DNA binding activity,AT-Pase activity,and DNA unwinding activity of BLM642-1290 DNA helicase could be significantly inhibi-ted by the fangchinoline derivative LYY-32.

Objective To investigate the effect of different decompression methods on the efficacy of the unilateral biportal endoscopy(UBE)in the treatment of severe lumbar spinal stenosis(LSS).Methods A total of 203 elderly patients with LSS who underwent UBE treatment in our hospital from September 2021 to June 2024 were selected and divided into the unilateral group(102 cases)and the bilateral group(101 cases)according to different decompression methods.The unilateral group underwent unilateral decompression during operation,while the bilateral group underwent bilateral decompression(with bilateral decompression through the same incision and unilateral approach)during operation.The perioperative conditions,anatomical image parameters,visual analogue scale(VAS)scores,Oswestry disability index(ODI),and complications were compared between the two groups.The rehabilitation progress and complications of patients with different Charlson comorbidity index(CCI)values were compared.Results The operation time of patients in the bilateral group was longer than that in the unilateral group(P<0.05).The dural sac area and lumbar spinal canal area of patients in the bilateral group were larger than those in the unilateral group immediately after operation and 3 months after operation(P<0.05).The VAS scores and ODI 7 days and 3 months after operation of patients in the bilateral group were lower than those in the unilateral group(P<0.05).There was no statistically significant difference in the total incidence of complications between the two groups of patients(P>0.05).The first time of getting out of bed after operation and hospital stay in patients with CCI value>2 scores were longer than those in patients with CCI value≤2 scores(P<0.05).Conclusion Compared with unilateral decompression,bilateral decompression for elderly patients with severe LSS takes a longer surgical time,but it can better restore lumbar shape,alleviate pain,improve lumbar function,and has higher safety,and the milder the patient's condition,the faster the postoperative recovery.

Objective To develop a novel protective ventilator circuit component and to verify its performance by water seal and anti-splash experiments.Methods A novel protective ventilator circuit component had a design scheme with the multifunctional joint,and consisted of a tee connection tube,an isolation sleeve and a stop sleeve,of which,the tee connection tube was made of polyethylene polymer material and the others were made of silicone material.The tee connection tube had a T-shaped structure with two standard connection ports,which was composed of an adapter,a sealing cap,a plug and a sealing ring;the isolation sleeve was in the shape of a cylinder with a raised bottom,which was inserted into the adapter;the stop sleeve was located in the isolation sleeve,with an inverted frustum of a cone at the bottom and a rounded hole in the middle of the inverted frustum.An open ventilator circuit tube was involved in the performance verification of the circuit component developed.In the water seal experiment,sputum aspiration was simulated and the heights of the liquid level drop in the L-shaped tubes were compared after sputum aspiration.In the anti-splash experiment,the infection rates on the surfaces of the sterile hole towels and gloves were calculated.Results Water seal experiment showed after sputum aspiration the open ventilator circuit tube had the liquid level at the L-shaped tube higher significantly than that of the circuit component;the anti-splash experiment indicated sputum aspiration resulted in the occurance of the splashing out of the secretion and 77.5%infection rate by the open ventilator circuit tube,while no splashing out and 0%infection rate by the circuit component developed.Conclusion The novel protective ventilator circuit component behaves well in sealing and anti-splashing,and thus is worthy of clinical application for sputum aspiration.[Chinese Medical Equipment Journal,2025,46(4):113-117]

Objective To compare the differences in dosimetry and treatment efficiency of three radiotherapy plans after left-sided breast-conserving surgery,including modified intensity-modulated radiation therapy(IMRT),cross-field volume-modulated arc therapy(VMAT)or improved VMAT,so as to provide references for clinical practice.Methods Three radiotherapy plans of modified IMRT,cross-field VMAT and improved VMAT were designed for 12 patients after left-sided-breast-conserving surgery.The modified IMRT with five irradiation fields and the improved VMAT with two arcs were modified by not setting cross-fields while determining the start and end angles with the rays passing through the least lung area.The cross-field VMAT had its start and end angles set based on the cross-fields.The doses to the target areas,peripheral organs at risk,heart and its substructures were evaluated,and dose verification was carried out.The three plans were compared in terms of treatment efficiency and gamma pass rate.SPSS 22.0 was used for statistical analysis.Results All the three plans behaved well in dose distribution.In terms of planning gross tumor volume dosimetry dosimetry,the improved VMAT and modified IMRT gained advantages than others in CI and D50,respectively,with the differences being significant(all P<0.05).In terms of planning target volume dosimetry,the modified IMRT had the V107 and D50 lower than those of the others,with the differences being significant(P<0.05).In terms of the protection of peripheral organs at risk,V5 of the left lung,Dmean of the right lung and Dmean of the healthy breast were lower in the modified IMRT plan than in the other 2 plans,with statistically significant differences(P<0.05);V20,V30,V35 and V40 of the left lung were lower in the modified VMAT plan than in the other 2 plans,with statistically significant differences(P<0.05).In terms of protection of heart and its substructures,the left ventricle V20,V30 and Dmean of the improved VMAT plan behaved better than those of other 2 plans,and the difference was statistically significant(all P<0.05).In terms of treatment efficiency,the cross-field VMAT plan had the lowest MU while highest treatment efficiency;the improved VMAT plan had the MU higher while the treatment efficiency lower than the cross-field VMAT plan;the modified IMRT plan had the highest MU while the lowest gamma pass rate,and the differences in the MUs and gamma pass rates among the three plans were statistically significant(P<0.05).Conclusion Under the same standard conditions,the cross-field VMAT and improved VMAT plans show technical advantages.Though the improved VMAT plan has the treatment efficiency lower than the cross-field VMAT,it decreases the possibility of radiocardiac injury in terms of dosimetry and thus can be used for radiotherapy after left-sided breast-conserving surgery.[Chinese Medical Equipment Journal,2025,46(4):45-51]