Leakage rate is a critical metric for evaluating protective efficacy of masks.This paper reviews the cur-rent status of experimental methods and numerical simulation studies for assessing the leakage rates of masks,and reveals that leakage rates are related to multiple factors.The inward and outward leakage rates of masks are further compared and analyzed,and the importance of developing a standardized test method for outward leakage rate is em-phasized.Finally,future development direction of mask leakage rate assessment is proposed,aiming to realize the scientific and comprehensive assessment on mask leakage rate and provide guidance for formulating public health policies.

Objective In response to the clinical needs for personalized wrist orthoses,a topological optimization design method was proposed to achieve an integrated macro-and micro-structural optimization of a personalized,lightweight,and comfortable wrist orthosis.Methods A composite biomechanical finite element model of the wrist orthosis and upper limb was established to quantify the effects of the orthosis geometry on its fixation performance and comfort.A multi-condition topological optimization and microstructure design approach was employed to optimize the non-load-bearing areas of the orthosis.The orthosis was manufactured using three-dimensional(3D)-printed polyether ether ketone(PEEK),and the feasibility of the design was validated.Results While maintaining mechanical strength,the weight of the 3D-printed PEEK orthosis was reduced by 28％compared to the traditional orthoses.Both the pressure at the skin contact interface and the results of a subjective questionnaire indicated that test subjects experienced a high level of comfort wearing the orthosis.Conclusions The orthosis design achieved personalization,lightweight structure,and high comfort while ensuring mechanical strength and fixation performance.

Stereotactic radiotherapy is widely favored because of its high treatment precision and less fractionations.ZND-A is a new domestic gamma-ray cone-beam focused stereotactic radiotherapy system.Herein the technical characteristics of ZND-A system are described in detail from the aspects of the treatment frame,gamma-ray module,collimator module,six-dimensional treatment couch module and image-guided system module,and the main parameters are compared with the mainstream gamma knife equipments at home and abroad.With reference to Response Evaluation Criteria in Solid Tumors(RECIST 1.1),the initial efficacy of the patients treated by the ZND-A system is analyzed to evaluate the advantages and disadvantages of the ZND-A system for providing a reference for the hospital clinical use of this type of gamma knife.

Aim To investigate the role and mechanism of RNA binding protein zinc finger protein 36(ZFP36)in vascular calcification.Methods Human aortic smooth muscle cells were infected with ZFP36-overex-pressing virus or transfected with ZFP36 siRNA,followed by high phosphate stimulation to observe the effect of overex-pression or knockdown of ZFP36 on smooth muscle cell calcification;RNA immunoprecipitation and stability experiments were used to detect whether Runx2 was the target gene of ZFP36;Smooth muscle specific ZFP36 knockout mice were generated and vitamin D was used to induce vascular calcification.Alizarin Red and Von Kossa staining were used to observe calcification of aortic vessels,and Western blot was used to detect Runx2 protein expression.Results ZFP36 expression was elevated under calcification-stimulating conditions.Overexpression of ZFP36 alleviated high phos-phate-induced smooth muscle cell calcification,while knockdown of ZFP36 exacerbated calcification.ZFP36 could bind to Runx2 mRNA and promote its degradation.At the cellular level,ZFP36 could inhibit smooth muscle cell calcification via Runx2.At the animal level,knockout of ZFP36 in smooth muscle exacerbated vascular calcification induced by vita-min D.Conclusion ZFP36 inhibits vascular calcification by targeting Runx2 mRNA and suppressing its expression in smooth muscle cells.

ObjectiveTo understand the whole genome characteristics and the information for genetic evolution in the two coxsackievirus A2 (CVA2) strains isolated from patients with herpangina in Shanghai, and to provide a scientific basis for the prevention and treatment of herpetic angina. MethodsTwo CAV2 strains isolated from patients with herpetic angina in Shanghai were performed whole genome sequencing and analysis for phylogenetics, nucleotide homology, and evolution. ResultsA phylogenetic analysis of the VP1 region revealed that the two Shanghai strains both belonged to CVA2 genotype D, with the highest homology to OL357660, a strain from Yunnan. The average nucleotide identity (ANI) of the whole genome between the two Shanghai strains was 98.88%, and the ANI of the whole genome comparisons to other CVA2 genotype D strains and CVA2 genotypes A-C strains ranged from 84.64% to 97.42% and from 79.21% to 84.20%, respectively. The two Shanghai strains had low homology in the 3D region compared to the existing CVA2 strains. The phylogenetic analysis and sliding window nucleotide similarity analysis indicated that the two Shanghai strains and the Yunnan OL357660 strain might constitute a new genetic lineage. ConclusionThe two CVA2 strains isolated for the first time in Shanghai are assigned to genotype D (GenBank: PQ130039 and PQ130040), which is identical to the existing subtype prevalent in China. As represented by the Shanghai strains, a new CVA2 genetic lineage is been identified. This study has enriched the data on genetic evolution and genetic variation of CVA2 in Shanghai, indicating the requirement to strengthen surveillance for the epidemiological pattern of CVA2.

Stereotactic radiotherapy is widely favored because of its high treatment precision and less fractionations.ZND-A is a new domestic gamma-ray cone-beam focused stereotactic radiotherapy system.Herein the technical characteristics of ZND-A system are described in detail from the aspects of the treatment frame,gamma-ray module,collimator module,six-dimensional treatment couch module and image-guided system module,and the main parameters are compared with the mainstream gamma knife equipments at home and abroad.With reference to Response Evaluation Criteria in Solid Tumors(RECIST 1.1),the initial efficacy of the patients treated by the ZND-A system is analyzed to evaluate the advantages and disadvantages of the ZND-A system for providing a reference for the hospital clinical use of this type of gamma knife.

Radiation-induced esophageal injury (RIEI) is a frequent complication following radiotherapy for thoracic and head-neck malignancies, which may lead to severe sequelae including esophageal stricture and perforation, adversely affecting patients' quality of life and therapeutic outcomes. With advancements in radiotherapy techniques — particularly the adoption of unconventional fractionation regimens, concurrent chemoradiotherapy, and combined molecular targeted / immunotherapy — the incidence of RIEI has been increasing. In this review, recent advances in understanding the pathogenesis, clinical manifestations, risk factors, and management strategies for RIEI were comprehensively summarized. Current therapeutic approaches have evolved beyond conventional anti-inflammatory and nutritional support to include novel interventions such as targeted therapy, free radical scavengers, and microbiota modulation, etc. Future research should prioritize the development of optimized, individualized prevention and treatment protocols to mitigate RIEI risk and improve patient prognosis.

Aim To investigate the role and mechanism of RNA binding protein zinc finger protein 36(ZFP36)in vascular calcification.Methods Human aortic smooth muscle cells were infected with ZFP36-overex-pressing virus or transfected with ZFP36 siRNA,followed by high phosphate stimulation to observe the effect of overex-pression or knockdown of ZFP36 on smooth muscle cell calcification;RNA immunoprecipitation and stability experiments were used to detect whether Runx2 was the target gene of ZFP36;Smooth muscle specific ZFP36 knockout mice were generated and vitamin D was used to induce vascular calcification.Alizarin Red and Von Kossa staining were used to observe calcification of aortic vessels,and Western blot was used to detect Runx2 protein expression.Results ZFP36 expression was elevated under calcification-stimulating conditions.Overexpression of ZFP36 alleviated high phos-phate-induced smooth muscle cell calcification,while knockdown of ZFP36 exacerbated calcification.ZFP36 could bind to Runx2 mRNA and promote its degradation.At the cellular level,ZFP36 could inhibit smooth muscle cell calcification via Runx2.At the animal level,knockout of ZFP36 in smooth muscle exacerbated vascular calcification induced by vita-min D.Conclusion ZFP36 inhibits vascular calcification by targeting Runx2 mRNA and suppressing its expression in smooth muscle cells.

Objective:To investigate the impact of central screw size on the stability of the glenoid baseplate in reverse shoulder arthroplasty using a finite element analysis.Methods:Four sizes of central screws (length × diameter) were designed: 25.0 mm×5.5 mm (G1), 30.0 mm×5.5 mm (G2), 25.0 mm×6.5 mm (G3), and 30.0 mm×6.5 mm (G4), along with a glenosphere, a baseplate, and peripheral screws. The central screw of group G1 was selected for a biomechanical test along with a set of customized prosthesis. The results were used to validate a finite element model. The validated finite element model was employed to analyze the central screws of 4 different sizes under a vertically downward 490 N load in simulation. After the model calculation was completed, the total displacement of each model, the maximum Von Mises stress on the bone surface at the baseplate-bone contact interface, the maximum Von Mises stress on the bone tissue around the screw-bone interface, the maximum value of the maximum principal strain (tensile strain), the maximum value of the minimum principal strain (compressive strain), the total volume of bone damage, and the volume of bone damage around the central screw were analyzed.Results:Insignificant differences were found in the total displacement and total volume of bone damage across the 4 models. On the bone surface at the baseplate-bone contact interface, the maximum Von Mises stress in G3 and G4 (11.26 MPa and 9.88 MPa, respectively) was slightly higher than that in G1 and G2 (9.11 MPa and 8.90 MPa, respectively). On the bone tissue around the screw-bone interface, G4 exhibited significantly higher maximum stress (15.82 MPa) and significantly higher maximum value of the maximum principal strain (10.09×10 -2) than G1 (8.51 MPa, 3.88×10 -2), G2 (9.45 MPa, 4.29×10 -2), and G3 (9.92 MPa, 3.92×10 -2), while the maximum value of the minimum principal strain in G3 (12.12×10 -2)was significantly higher than that in G1 (8.23×10 -2), G2 (8.10×10 -2), and G4 (8.34×10 -2). The volume of bone damage around the central screw in G3 (11.4 mm 3) was significantly smaller than that in G1 (24.9 mm 3), G2 (28.5 mm 3), and G4 (20.3 mm 3). Conclusions:In reverse shoulder arthroplasty, to a certain extent, increasing the length of a central screw amplifies bone damage volume around the screw. Conversely, increasing only the diameter of a central screw reduces bone damage volume around the screw, consequently lowering the loosening risk of a central screw.

Radiation-induced esophageal injury (RIEI) is a frequent complication following radiotherapy for thoracic and head-neck malignancies, which may lead to severe sequelae including esophageal stricture and perforation, adversely affecting patients' quality of life and therapeutic outcomes. With advancements in radiotherapy techniques — particularly the adoption of unconventional fractionation regimens, concurrent chemoradiotherapy, and combined molecular targeted / immunotherapy — the incidence of RIEI has been increasing. In this review, recent advances in understanding the pathogenesis, clinical manifestations, risk factors, and management strategies for RIEI were comprehensively summarized. Current therapeutic approaches have evolved beyond conventional anti-inflammatory and nutritional support to include novel interventions such as targeted therapy, free radical scavengers, and microbiota modulation, etc. Future research should prioritize the development of optimized, individualized prevention and treatment protocols to mitigate RIEI risk and improve patient prognosis.