On the pressure resistant clothing,suitcases and bags,a load-bearing zipper is an effective device to keep pressure and fold-unfold the structure.The load-bearing zipper should has a high-strength and moderate operation force.A model of zipper was established and the changing process bearing the breaking strength crosswise of chain was calculated by finite element software Ansys,and the structure sizes were improved according on the fracture mechanism.A kind of high strength zipper was obtained by the continuous molding nylon zipper tooth and the properties were measured.An air pressure bag was made to evaluate the performance in use.Results indicate that the breaking strength crosswise of chain reaches 2000 N/25 mm with a moderate 14.5 N tab pull-off strength,which means the load-bearing zipper could meet the requirements of high strength pressure resistant structures.

Algorithmic systems based on artificial intelligence(AI)and machine learning(ML)have undergone rapid advancement in recent years, demonstrating extensive application across diverse ophthalmic disorders. Owing to the public availability of multiple global databases, significant progress has been achieved in the training and development of AI-integrated algorithms utilizing multimodal ophthalmic imaging modalities, including fundus photography and optical coherence tomography(OCT). These advancements have established a foundation for precision medicine and efficient healthcare delivery. The diagnosis of macular diseases relies on the identification of subtle alterations in tissue anatomy, where AI demonstrated exceptional performance in detecting intraocular biomarkers and evaluating anatomical changes during disease progression, with particularly prominent utility in the field of macular pathologies. This article provides a comprehensive review of the current applications of AI in macular diseases, aiming to synthesize existing research achievements and current challenges, while proposing visionary prospects for the broader implementation of AI in ophthalmology and even systemic medicine in the future.

Objective:To investigate the diagnostic efficacy of artificial intelligence(AI)software combined with contrast-enhanced ultrasound(CEUS)on portal hypertension of cirrhosis.Methods:A retrospective analysis was conducted on 106 patients with cirrhosis who admitted to Handan Communicable Disease Hospital from January 2024 to June 2024 and were confirmed by surgical pathology.In them,60 cases with positive portal hypertension were included in positive group,and 46 cases with negative portal hypertension were included in negative group.The receiver operating characteristic(ROC)curve was used to analyze the diagnostic values of ultrasound characteristics via preoperative AI quantization,enhanced ultrasound mode and the combination of them for portal hypertension of cirrhosis.Results:The mean peak intensity,mean vessel density and branching morphology index of AI software were respectively 201.23±10.18,0.62±0.11 and 1.23±0.24 in diagnosing portal hypertension of positive group,all of which were significantly higher than those of negative group(t=8.551,3.707,2.054,P<0.05).However,the mean peak reaching time,uniformity of flow perfusion,mean flow velocity and uniformity of microcirculation perfusion of the positive group were respectively(18.22±2.18)seconds,(75.22±5.46)%,(10.09±2.22)cm/s,(80.78±5.11)%,all of which were significantly lower than those in the negative group(t=3.729,5.237,4.969,4.491,P<0.05).The enhancement speed and degree of liver parenchyma,the enhancement speed of portal vein,and the enhancement speed and degree of spleen in CEUS of positive group were significantly higher than those of negative group,and the differences were significant(t=4.770,12.781,7.313,5.501,4.645,7.513,P<0.05).ROC curve analysis showed that the area under curve(AUC)value of CEUS combined with AI algorithm was 0.926 in diagnosis,which was significantly better than single CEUS and single AI analysis(0.853,0.925).Conclusion:CEUS technique combines with AI software can show higher diagnostic efficacy in the diagnosis for portal hypertension of cirrhosis,which diagnostic effect was better than single either of two methods.

Objective:To investigate the diagnostic efficacy of artificial intelligence(AI)software combined with contrast-enhanced ultrasound(CEUS)on portal hypertension of cirrhosis.Methods:A retrospective analysis was conducted on 106 patients with cirrhosis who admitted to Handan Communicable Disease Hospital from January 2024 to June 2024 and were confirmed by surgical pathology.In them,60 cases with positive portal hypertension were included in positive group,and 46 cases with negative portal hypertension were included in negative group.The receiver operating characteristic(ROC)curve was used to analyze the diagnostic values of ultrasound characteristics via preoperative AI quantization,enhanced ultrasound mode and the combination of them for portal hypertension of cirrhosis.Results:The mean peak intensity,mean vessel density and branching morphology index of AI software were respectively 201.23±10.18,0.62±0.11 and 1.23±0.24 in diagnosing portal hypertension of positive group,all of which were significantly higher than those of negative group(t=8.551,3.707,2.054,P<0.05).However,the mean peak reaching time,uniformity of flow perfusion,mean flow velocity and uniformity of microcirculation perfusion of the positive group were respectively(18.22±2.18)seconds,(75.22±5.46)%,(10.09±2.22)cm/s,(80.78±5.11)%,all of which were significantly lower than those in the negative group(t=3.729,5.237,4.969,4.491,P<0.05).The enhancement speed and degree of liver parenchyma,the enhancement speed of portal vein,and the enhancement speed and degree of spleen in CEUS of positive group were significantly higher than those of negative group,and the differences were significant(t=4.770,12.781,7.313,5.501,4.645,7.513,P<0.05).ROC curve analysis showed that the area under curve(AUC)value of CEUS combined with AI algorithm was 0.926 in diagnosis,which was significantly better than single CEUS and single AI analysis(0.853,0.925).Conclusion:CEUS technique combines with AI software can show higher diagnostic efficacy in the diagnosis for portal hypertension of cirrhosis,which diagnostic effect was better than single either of two methods.

Objective To investigate the neurobehavioral effects of long-term mild hypothermia(MHT)combined with compound porcine cerebroside and ganglioside injection(CPCGI)after traumatic brain injury(TBI)in rats and its mechanism.Methods 36 healthy adult male SD rats were randomly divided into model group,MHT group,CPCGI group and MHT+CPCGI group.The TBI model was prepared using an electronically controlled cortical in-jury device.The rats in model group received an intraperitoneal injection of an equal amount of normal saline(NS,2 ml/kg)and were treated at room temperature(37℃)for 48 hours.The rats in MHT group received an intraper-itoneal injection of an equal amount of NS and were treated at a slightly low temperature(33.0±1.0)℃for 48 hours.The rats in CPCGI group received an intraperitoneal injection of an equal amount of CPCGI(0.6 ml/kg)and were treated at room temperature for 48 hours.The rats in MHT+CPCGI group received an intraperitoneal in-jection of an equal amount of CPCGI and were treated at a slightly low temperature for 48 hours.The sensorimotor function of rats was evaluated by modified Neurological Severity Score(mNSS).The motor and spatial memory a-bilities of rats were detected by Morris water maze test,and the motor function of rats was evaluated by beam walk-ing test(BWT)and inclined-grid climbing test.The number of neurons in hippocampus was observed by Nissl stai-ning and immunofluorescence was used to detect the expression of doublecortin(DCX)and neuronal nuclear anti-gen antibody(NeuN).Western blot was used to observe the protein expression of B-cell lymphoma-2(Bcl-2),Bcl-2 associated X protein(Bax)and cysteine proteinase-3(Caspase-3).Results Compared with MHT group and CPCGI group,MHT+CPCGI group had a lower mNNS score,shorter escape latency,higher times across the platform and the percentage of time in the target quadrant,higher BWT score and larger climbing angle,increased numbers of neurons,DCX and NeuN positive cells,increased Bcl-2 expression and decreased expression of Bax and Caspase-3.(P<0.05).Conclusion Long-term mild hypothermia combined with CPCGI can effectively im-prove the neurological deficits of TBI rats by promoting nerve regeneration and inhibiting cell apoptosis,and provide potential strategies and basis for the clinical treatment of TBI.

Neuromyelitis optica spectrum disorders (NMOSD) are a group of autoimmune-mediated demyelinating diseases of the central nervous system. A growing number of studies have identified asymptomatic lesions on imaging in patients with NMOSD, including asymptomatic optic neuropathy, asymptomatic spinal lesions, and asymptomatic brain lesions, even in the absence of clinical symptoms. The characteristics of asymptomatic lesions of NMOSD, influencing factors, relationship with relapse and disability progression, and management strategies were reviewed in this article.

Objective:To investigate the relationship between vaccination doses and the duration of positive nucleic acid or antigen tests in Corona Virus Disease 2019 (COVID-19) patients during omicron epidemic.Methods:A cross-sectional study was conducted from December 26 to December 31, 2022 among COVID-19 patients from all community health service centers in 16 districts of Beijing municipality selected by multi-stage stratified cluster quota sampling method. A questionnaire was used to collect the basic information, vaccination doses, results of nucleic acid or antigen tests of all subjects. The subjects were divided into 5 groups according to the doses of COVID-19 vaccination: the non-vaccination group, the 1, 2, 3 and 4 doses vaccination group. The relationship between vaccination doses and the duration of positive nucleic acid or antigen tests was analyzed by univariate and multivariate logistic regression models.Results:A total of 10 506 COVID-19 cases were included in the study with the age of (43.3±13.7) years. The duration of positive nucleic acid or antigen tests was longer than 7 days in 59.4%(276/465), 51.5%(67/130), 50.6%(355/701), 46.1% (3 464/7 520) and 39.2%(662/1 690) of non-vaccination, and 1, 2, 3, 4 dose vaccination groups, respectively ( P<0.001). Multivariate logistic regression analysis showed that compared with non-vaccination patients, the vaccination dose was an independent protective factor for duration of positive nucleic acid or antigen tests>7 days, and the OR values were 0.7 (95% CI 0.5-0.9, P=0.015), 0.6 (95% CI 0.5-0.8, P<0.001) and 0.5 (95% CI 0.4-0.6, P<0.001) for 2, 3 and 4 doses of vaccination, respectively. Conclusion:The vaccination doses are independently related to the duration of positive nucleic acid or antigen tests in COVID-19 patients and the risk is gradually decreases with the increasing vaccination doses.

Abstract Flood disasters are the common public health emergencies, mainly leading to environmental damage, water pollution, food pollution, vector breeding, infectious disease epidemic and other risk factors of sanitary and anti epidemic work. The guideline has been formulated with reference to the technical documents such as Guideline for Environmental Sanitation Disposal and Preventive Disinfection in Flooded Areas and Technical Proposal for Sanitary and Anti epidemic Measures after Flood Disasters, as well as the latest research progress at home and abroad. In order to guide the sanitary and anti epidemic measures in flooded areas, protect the health and safety of students and teachers and ensure the normal educational and teaching order, the guideline introduces the key measures that should be taken by schools, teachers and students in flood striken areas.

Objective:To understand the status of knowledge, attitude and practice of metabolic syndrome(MS) among the elderly in the community and analyze its influencing factors, so as to provide guidance for the prevention and treatment of MS.Methods:From January 2021 to August 2021, permanent residents(residence duration ≥6 months)aged 65 and above with regular health check examination in Fangzhuang Community Health Service Center of Fengtai District, Beijing were investigated using self-designed MS knowledge, attitude and practice questionnaire.After excluding 34 incomplete questionnaires, the 491 valid questionnaires were recycled with questionnaire valid percentage of 93.5%(491/525). The survey results were analyzed by descriptive analysis, Mann-Whitney U test, Kruskal-Wallis H test and multiple linear regression analysis and multiple linear regression.Results:The scores of MS knowledge, attitude and practice of the elderly in the community were 7(5, 10), 9(8, 10)and 19(18, 21)respectively.The correct answer rate of the diagnostic criteria of MS components was less than 50%.The score of knowledge about MS in the elderly was positively correlated with the scores of attitudes( r=0.263)and practice( r=0.134)(all P<0.01). The results of univariate and multiple linear regression analysis showed that gender, attending educational lectures and the prevalence of MS were the influencing factors of MS knowledge score(all P<0.05). Leisure time, attending educational lectures, pre-retirement occupation and regular health check examination were the influencing factors for MS attitude score(all P<0.05); attending educational lectures, leisure time, regular health check examination and pre-retirement occupation were the influencing factors for MS practice score(all P<0.05). Conclusions:The elderly in the community have a low level of knowledge about the components and diagnostic criteria of MS, but have a positive attitude and practice towards the prevention and treatment of MS.The level of knowledge, attitude and practice of MS is affected by health education lectures, occupation, regular health check examination and other factors.Health education on the diagnostic criteria and the awareness of disease prevention for the elderly in the community should be strengthened to improve the levels of the knowledge, attitude and practice of MS.

Objective To compare the effect and safety of stenting versus directional atherectomy (DA) in the treatment of TASCⅡ A and B superficial femoral artery lesions.Methods 100 patients with TASC Ⅱ A and B lesions were divided into percutaneous transluminal stenting(PTS) group (n =50) and DA group (n =50).Patients were compared in terms of technical success rate,treatment success rate,first operation cost,postoperative ankle brachial index (ABI),limb salvage rate,survival,and patency.Results The technical success rate in both PTS and DA group was 100％.The treatment success rate was 98％ vs.86％,P＞0.05.Postoperative ABI:0.82 ±0.19 vs.0.80 ±0.27,P＞0.05.First operation cost:(34 820 ± 1 051) yuan vs.(45 635 ± 1 358) yuan,P ＜0.001;All patients were followed-up for up to 2-year,the cumulative patency rate was 81.6％ vs.72.9％ (P＞0.05).Limb salvage rate was 97.9％ vs.93.8 ％,P ＞ 0.05.Conclusion There were no significant differences in the effect and safety of PTS versus DA in the treatment of TASCⅡ A and B superficial femoral artery lesions.