针对线控转向(steer by wire, SBW)系统主动转向时面临的系统参数不确定性、轮胎回正力矩阻碍、转向电机电磁特性耦合等非线性干扰问题,提出一种自适应抗扰转角控制策略。采用径向基函数神经网络和鲁棒滑模理论设计外环转角控制器,自适...针对线控转向(steer by wire, SBW)系统主动转向时面临的系统参数不确定性、轮胎回正力矩阻碍、转向电机电磁特性耦合等非线性干扰问题,提出一种自适应抗扰转角控制策略。采用径向基函数神经网络和鲁棒滑模理论设计外环转角控制器,自适应补偿SBW系统参数不确定性和轮胎回正力矩阻碍。在内环电流控制器中引入线性自抗扰控制应对转向执行电机电磁特性耦合问题,提高SBW系统动态响应性能。仿真和硬件在环试验结果表明,设计的控制策略能够帮助SBW在多种工况中维持转角稳态跟随误差在1.5°内。展开更多
Objective:Postpartum nutrition plays a critical role in maternal recovery and long-term health.However,the nutritional status of working mothers in the postpartum period remains understudied.This study aimed to assess...Objective:Postpartum nutrition plays a critical role in maternal recovery and long-term health.However,the nutritional status of working mothers in the postpartum period remains understudied.This study aimed to assess the dietary quality of postpartum women in urban Beijing,identify occupational-related factors influencing their diet,and explore potential interventions to improve maternal nutrition during the postpartum period.Methods:In this cross-sectional analysis,554 women one year after delivery were recruited from ten community health centers.Sociodemographic,occupational and postpartum care variables were collected via questionnaire.Dietary intake over the preceding year was assessed using a food frequency questionnaire.The modified dietary balance index for postpartum women were used for dietary quality assessment.Results:The study revealed severe dietary imbalances among postpartum women,characterized by excessive consumption of cereals,eggs,and meats,while their intake of vegetables,fruits,and dairy products was inadequate.According to dietary balance index for postpartum women,66.25%of mothers showed varying degrees of excessive intake.45.31%of mothers experienced varying levels of insufficient intake,with only 19.86%of participants having a relatively balanced diet.Occupational differences were observed,with women in the commercial employment group showing higher levels of excessive food intake.The analysis of influencing factors showed that family monthly income,maternity leave,and postpartum care significantly affected the dietary quality.Conclusions:Postpartum women in Beijing experience widespread dietary imbalances,with both excesses and deficiencies.Occupational context and related factors significantly shape diet quality.These findings highlight the need for targeted nutritional interventions tailored to the specific challenges of different occupational groups.展开更多
Erythroid cells, the predominant circulating blood cells, are essential for oxygen and carbon dioxide transport (Obeagu, 2024).Their production, erythropoiesis, involves the coordinated synthesis of globin chains and ...Erythroid cells, the predominant circulating blood cells, are essential for oxygen and carbon dioxide transport (Obeagu, 2024).Their production, erythropoiesis, involves the coordinated synthesis of globin chains and heme molecules to assemble hemoglobin(Zhang et al., 2021). The erythroid-specific enzyme δ-aminolevulinate synthase 2 (ALAS2) is a key rate-limiting factor in heme biosynthesis,with its expression increasing in late-stage erythropoiesis to meet heme demands (Sadlon et al., 1999). Zebrafish (Danio rerio) is a well-established model for studying erythropoiesis due to its genetic tractability and optical transparency (Zhang and Hamza, 2019;Zhang et al., 2021). The Tol2-mediated Gal4-UAS system has been widely applied for gene and enhancer trapping in zebrafish (Asakawa and Kawakami, 2009). However, reliable Gal4 enhancer-trap lines for erythropoiesis remain limited. Here, we report a transgenic zebrafish line with erythroid-specific Gal4FF expression under the control of the endogenous alas2 promoter, offering a more precise erythroblast labeling than the gata1a reporter line. This model provides a valuable tool for erythroid-specific investigations of blood flow dynamics and gene function.展开更多
Taking into account the characteristics of non-Newtonian fluids and the influence of latent heat of wax crystallization,this study establishes physical and mathematical models for the synergy of tubular heating and me...Taking into account the characteristics of non-Newtonian fluids and the influence of latent heat of wax crystallization,this study establishes physical and mathematical models for the synergy of tubular heating and mechanical stirring during the waxy crude oil heating process.Numerical calculations are conducted using the sliding grid technique and FVM.The focus of this study is on the impact of stirring rate(τ),horizontal deflection angle(θ1),vertical deflection angle(θ2),and stirring diameter(D)on the heating effect of crude oil.Our results show that asτincreases from 200 rpm to 500 rpm and D increases from 400 mm to 600 mm,there is an improvement in the average crude oil temperature and temperature uniformity.Additionally,heating efficiency increases by 0.5%and 1%,while the volume of the low-temperature region decreases by 57.01 m^(3) and 36.87 m3,respectively.Asθ1 andθ2 increase from 0°to 12°,the average crude oil temperature,temperature uniformity,and heating efficiency decrease,while the volume of the low-temperature region remains basically the same.Grey correlation analysis is used to rank the importance of stirring parameters in the following order:τ>θ1>θ2>D.Subsequently,multiple regression analysis is used to quantitatively describe the relationship between different stirring parameters and heat transfer evaluation indices through equations.Finally,based on entropy generation minimization,the stirring parameters with optimal heat transfer performance are obtained when τ=350 rpm,θ1=θ2=0°,and D=500 mm.展开更多
This paper investigated and analyzed the conservation and utilization of four local livestock breeds in Binzhou City:Wadi Sheep,Bohai Black Cattle,Wudi Donkey,and Lubei White Goat.Shortcomings in the protection and ut...This paper investigated and analyzed the conservation and utilization of four local livestock breeds in Binzhou City:Wadi Sheep,Bohai Black Cattle,Wudi Donkey,and Lubei White Goat.Shortcomings in the protection and utilization of local germplasm resources were pointed out,and strategies and recommendations were proposed to promote high-quality development of livestock and poultry genetic resources in Binzhou,including building a solid germplasm foundation,standardizing production,and driving innovation.This paper provides references for the conservation,development,and utilization of local genetic resources in Binzhou City.展开更多
Selective catalytic transfer hydrogenation(CTH)of carbonyl compounds to obtain specific alcohols holds significant importance across various fields.Achieving multiple selectivity in CTH is particularly crucial,but ful...Selective catalytic transfer hydrogenation(CTH)of carbonyl compounds to obtain specific alcohols holds significant importance across various fields.Achieving multiple selectivity in CTH is particularly crucial,but full of great challenge.Herein,a cationic In-captured Zr-porphyrin framework(1)with nanosized pores/cages was successfully constructed and showed high structure stability.Catalytic investigations revealed that 1 displayed highly multi-selective CTH of aldehydes and ketones containing both chemo-and size selectivity for the first time.The CTH of aldehydes and ketones exhibited remarkable reductive selectivity of 99%towards C=O bonds into CH–OH in the presence of-NO_(2),-CN and C=C groups.Through tuning the reaction conditions,1 also exhibited highly selective reduction of 97%for-CHO groups in the simultaneous presence of-CHO and-COCH3groups in intra-and intermolecular settings.Remarkably,reductive selectivity towards-CHO group remained prominent among five concurrent unsaturated groups mentioned above.Additionally,the definite pore size of 1 facilitated volume control of substrates,enabling size selectivity.1 as a heterogeneous catalyst was further confirmed by leaching tests,and maintained high activity even after being used for at least six cycles.Mechanistic studies have revealed that Zr6O8clusters served as the catalytic centers and the observed chemoselectivity mainly results from the synergistic effect of distinct metal sites within 1.The heightened selectivity towards-CHO over-COCH_(3)can be attributed to the easier realization of transfer hydrogenation processes for-CHO compared to-COCH_(3).展开更多
This paper systematically analyzed the development status of sheep industry in Lubei region,and comprehensively expounded the scale and distribution of key industries,breed resources and genetic characteristics,feedin...This paper systematically analyzed the development status of sheep industry in Lubei region,and comprehensively expounded the scale and distribution of key industries,breed resources and genetic characteristics,feeding management status,disease prevention and control and veterinary services,and sheep product processing and sales.The research shows that the sheep industry in Lubei region has formed a certain scale,but there are some problems such as intensified resource and environmental constraints,unreasonable industrial structure,insufficient scientific and technological innovation capacity and market competitiveness to be improved.In view of these problems,this paper put forward some countermeasures and suggestions to promote the high-quality development of the industry,including establishing forage and feed system,promoting the adjustment and optimization of industrial structure,strengthening scientific and technological innovation and talent cultivation and introduction,and enhancing brand influence and market competitiveness,providing useful reference for the sustainable development of sheep industry in Lubei region.展开更多
Background:Over the past 15 years,research has emphasized the crucial role of the gut microbiota in metabolism and its potential association with osteoporosis.Given the increasing interest in this area,a bibliometric ...Background:Over the past 15 years,research has emphasized the crucial role of the gut microbiota in metabolism and its potential association with osteoporosis.Given the increasing interest in this area,a bibliometric analysis is essential to comprehensively understand the field.Methods:Literature published between 2009 and 2023 was retrieved from the Web of Science.CiteSpace,a tool for visual analysis,was employed to examine various aspects of the research,including the annual number of publications,contributing institutions,journals,authors,keywords,clusters,hotspots,and emerging frontiers.Results:The analysis included 1,075 articles from 80 countries,283 institutions,and 155 authors,reflecting the rapid growth of research in this field.PEOPLES R CHINA emerged as the most productive country,while the University of California System was the most active institution.Parameswaran,Narayanan had the highest number of publications,and LI JY and OHLSSON C were the most cited authors.Key keywords such as“gut microbiota,”“bone loss,”“bone mineral density,”“inflammation,”and“health”were identified,and keywords with strong citation bursts like“in vitro,”“inflammatory bowel disease,”and“bone mineral density”indicated emerging trends.Conclusion:This bibliometric analysis successfully identified research trends and hotspots,including the fecal microbiome,musculoskeletal studies,and postmenopausal women.Continued research in these areas will enhance our understanding of osteoporosis and may lead to the development of new treatments.The findings offer valuable insights for scholars aiming to conduct in-depth research in this field.展开更多
Gas–liquid two-phase jets exhibit markedly enhanced impact performance due to the violent collapse of entrained bubbles,which generates transient microjets and shock waves.The geometry of the nozzle is a decisive fac...Gas–liquid two-phase jets exhibit markedly enhanced impact performance due to the violent collapse of entrained bubbles,which generates transient microjets and shock waves.The geometry of the nozzle is a decisive factor in controlling jet formation,flow modulation,and impact efficiency.In this work,the structural optimization of gas–liquid two-phase nozzles was investigated numerically using the Volume of Fluid(VOF).Simulation results show that the aero-shaped nozzle delivers a significantly stronger impact on the target surface than conventional geometries.Specifically,its impact pressure is 21%higher than that of a conical straight nozzle and 37%higher than that of a conical nozzle.The aero nozzle not only increases peak impact pressure but also sustains it over a longer duration,leading to an overall improvement in energy transfer efficiency.Parametric analyses further reveal the key geometric conditions governing performance.When the nozzle curvature is set to 0.01,the jet achieves a higher and more stable surface pressure profile,maintaining elevated impact for a prolonged period.At an aspect ratio of 15,the jet exhibits pronounced pulsation under high pressure,thereby enhancing impact intensity.The contraction ratio exerts a non-monotonic influence:as it increases,impact pressure initially rises and subsequently declines,with an optimal value of 4 yielding the highest and most persistent impact pressure.Likewise,when the ratio of inlet length to outlet diameter is 2.5,the jet demonstrates the strongest impact on the target surface.展开更多
BACKGROUND Sepsis-induced intestinal injury disrupts barrier function and exacerbates systemic inflammation,contributing to high mortality.AIM To investigate the mechanism by which sphinganine protects against sepsisi...BACKGROUND Sepsis-induced intestinal injury disrupts barrier function and exacerbates systemic inflammation,contributing to high mortality.AIM To investigate the mechanism by which sphinganine protects against sepsisinduced intestinal injury,focusing on macrophage polarization and toll like receptor 2(TLR2)/nuclear factor kappa-B(NF-κB)signaling.METHODS A cecal ligation and puncture sepsis model was established in mice(n=20/group).Treatments included sphinganine(15 mg/kg)and a TLR2 agonist[fibroblast-stimulating lipopeptide-1(FSL-1),10μg/kg].Serum markers[diamine oxidase(DAO),interleukin(IL)-1β,tumor necrosis factor(TNF)-α,IL-6]were measured by enzyme-linked immunosorbent assay.Intestinal injury and macrophage polarization[cluster of differentiation(CD)86^(+)M1,CD206^(+)M2]were assessed via hematoxylin and eosin and immunofluorescence staining.Proteomic analysis,molecular docking,and Western blot were used to evaluate TLR2/NF-κB signaling.Data were analyzed by analysis of variance and t-test.RESULTS Sphinganine significantly reduced serum levels of DAO(P<0.05),IL-1β,TNF-α,and IL-6(P<0.05),preserved intestinal crypt structure,and enhanced tight junction protein zonula occludens-1 expression.It promoted a shift from M1(CD86^(+))to M2(CD206^(+))macrophages.Proteomics identified TLR2 as the most differentially expressed protein,and molecular docking confirmed strong binding between sphinganine and TLR2(-4.3 kcal/mol).Sphinganine downregulated TLR2 and phosphorylated-NF-κB p65 expression(P<0.05),effects reversed by FSL-1.Total NF-κB p65 levels remained unchanged.CONCLUSION Sphinganine protects against sepsis-induced intestinal injury by inhibiting TLR2/NF-κB signaling,modulating macrophage polarization toward the M2 phenotype,and preserving intestinal barrier integrity.展开更多
Objective:To investigate the clinical efficacy and safety of the extrapleural approach versus the traditional intrathoracic approach in minimally invasive correction of pectus excavatum in children,providing a more sc...Objective:To investigate the clinical efficacy and safety of the extrapleural approach versus the traditional intrathoracic approach in minimally invasive correction of pectus excavatum in children,providing a more scientific basis for selecting a more appropriate surgical method in clinical practice.Methods:This study included 50 children who underwent pectus excavatum correction at Harbin Children’s Hospital from January 2023 to January 2025.All patients were divided into two groups based on surgical approach:the observation group(n=26)and the control group(n=24).Children in the observation group underwent correction surgery via an extrapleural approach,while those in the control group underwent correction surgery via the traditional intrathoracic approach.Both groups underwent Nuss bar placement surgery under thoracoscopic guidance.Intraoperative indicators were compared between the two groups,including operative time,blood loss,pain scores at 24 and 48 hours postoperatively,hospital stay duration,thoracic correction outcomes,and the incidence of complications during a 6-month postoperative follow-up.Results:The intraoperative blood loss in the observation group was significantly lower than that in the control group(p<0.05),and the pain scores at 24 and 28 hours postoperatively were also significantly lower(p<0.05).The improvement in thoracic index postoperatively was relatively similar between the two groups,with no statistically significant difference(p>0.05).During the 6-month postoperative follow-up period,no complications such as pneumothorax,hemothorax,pleural effusion,plate displacement,or infection occurred in the observation group,whereas the overall complication rate in the control group was 25%,showing a significant difference(p<0.05).Conclusion:The extrapleural approach for corrective surgery can ensure the efficacy of thoracic deformity correction while reducing intraoperative blood loss,lowering the incidence of complications,alleviating postoperative pain,and accelerating recovery.It is a safe and effective approach for minimally invasive Nuss correction of pediatric pectus excavatum.展开更多
The anti-inflammatory properties of silkworm pupa peptide(SPP)have been recognized for their potential benefits in colitis treatment.However,the underlying mechanism of SPP in colitis animal models remains unclear.The...The anti-inflammatory properties of silkworm pupa peptide(SPP)have been recognized for their potential benefits in colitis treatment.However,the underlying mechanism of SPP in colitis animal models remains unclear.The objective of our work was to investigate the improving effect and the mechanism of action of SPP on a mouse model of dextran sulfate sodium(DSS)-induced colitis.The findings suggested that SPP effectively eased ulcerative colitis(UC)symptoms in mice by decreasing disease activity index,ameliorating histopathological injury,and decreasing serum and colonic markers of inflammation.In addition,our research findings demonstrated that SPP restored intestinal barrier function by increasing the production of tight junction proteins such as zonula occludens-1(ZO-1),claudin-1,claudin-3,occludin,and adherens junction protein E-cadherin1.Further,SPP supplementation enhanced the concentration of short-chain fatty acids and positively altered the makeup of the gut bacteria in the mice's gut.These findings underscore SPP's ability to slow the progression of colitis and point to its possible use as a functional component in dietary supplements for the prevention of early-stage colitis.展开更多
Network intrusion detection systems(IDS)are a prevalent method for safeguarding network traffic against attacks.However,existing IDS primarily depend on machine learning(ML)models,which are vulnerable to evasion throu...Network intrusion detection systems(IDS)are a prevalent method for safeguarding network traffic against attacks.However,existing IDS primarily depend on machine learning(ML)models,which are vulnerable to evasion through adversarial examples.In recent years,the Wasserstein Generative Adversarial Network(WGAN),based on Wasserstein distance,has been extensively utilized to generate adversarial examples.Nevertheless,several challenges persist:(1)WGAN experiences the mode collapse problem when generating multi-category network traffic data,leading to subpar quality and insufficient diversity in the generated data;(2)Due to unstable training processes,the authenticity of the data produced by WGAN is often low.This study improves WGAN to address these issues and proposes a new adversarial sample generation algorithm called Distortion Enhanced Multi-Generator Generative Adversarial Network(DEMGAN).DEMGAN effectively evades ML-based IDS by proficiently obfuscating network traffic data samples.We assess the efficacy of our attack method against five ML-based IDS using two public datasets.The results demonstrate that our method can successfully bypass IDS,achieving average evasion rates of 97.42%and 87.51%,respectively.Furthermore,empirical findings indicate that retraining the IDS with the generated adversarial samples significantly bolsters the system’s capability to detect adversarial samples,resulting in an average recognition rate increase of 86.78%.This approach not only enhances the performance of the IDS but also strengthens the network’s resilience against potential threats,thereby optimizing network security measures.展开更多
Numerical simulation plays an important role in the dynamic analysis of multibody system.With the rapid development of computer science,the numerical solution technology has been further developed.Recently,data-driven...Numerical simulation plays an important role in the dynamic analysis of multibody system.With the rapid development of computer science,the numerical solution technology has been further developed.Recently,data-driven method has become a very popular computing method.However,due to lack of necessary mechanism information of the traditional pure data-driven methods based on neural network,its numerical accuracy cannot be guaranteed for strong nonlinear system.Therefore,this work proposes a mechanism-data hybrid-driven strategy for solving nonlinear multibody system based on physics-informed neural network to overcome the limitation of traditional data-driven methods.The strategy proposed in this paper introduces scaling coefficients to introduce the dynamic model of multibody system into neural network,ensuring that the training results of neural network conform to the mechanics principle of the system,thereby ensuring the good reliability of the data-driven method.Finally,the stability,generalization ability and numerical accuracy of the proposed method are discussed and analyzed using three typical multibody systems,and the constrained default situations can be controlled within the range of 10^(-2)-10^(-4).展开更多
With the rapid proliferation of Internet ofThings(IoT)devices,ensuring their communication security has become increasingly important.Blockchain and smart contract technologies,with their decentralized nature,provide ...With the rapid proliferation of Internet ofThings(IoT)devices,ensuring their communication security has become increasingly important.Blockchain and smart contract technologies,with their decentralized nature,provide strong security guarantees for IoT.However,at the same time,smart contracts themselves face numerous security challenges,among which reentrancy vulnerabilities are particularly prominent.Existing detection tools for reentrancy vulnerabilities often suffer from high false positive and false negative rates due to their reliance on identifying patterns related to specific transfer functions.To address these limitations,this paper proposes a novel detection method that combines pattern matching with deep learning.Specifically,we carefully identify and define three common patterns of reentrancy vulnerabilities in smart contracts.Then,we extract key vulnerability features based on these patterns.Furthermore,we employ a Graph Attention Neural Network to extract graph embedding features from the contract graph,capturing the complex relationships between different components of the contract.Finally,we use an attention mechanism to fuse these two sets of feature information,enhancing the weights of effective information and suppressing irrelevant information,thereby significantly improving the accuracy and robustness of vulnerability detection.Experimental results demonstrate that our proposed method outperforms existing state-ofthe-art techniques,achieving a 3.88%improvement in accuracy compared to the latest vulnerability detection model AME(Attentive Multi-Encoder Network).This indicates that our method effectively reduces false positives and false negatives,significantly enhancing the security and reliability of smart contracts in the evolving IoT ecosystem.展开更多
Tensile cracking is a predominant mode of failure in rocks within underground resource excavation and engineering structures,where rocks are frequently subjected to dynamic disturbances while simultaneously experienci...Tensile cracking is a predominant mode of failure in rocks within underground resource excavation and engineering structures,where rocks are frequently subjected to dynamic disturbances while simultaneously experiencing in-situ stresses.This paper proposes a new dynamic split tension setup utilising a cubic specimen to investigate the dynamic behaviour of rocks across various tensile strain rates and confining pressures.The objective is to extend the applicability of the triaxial Hopkinson bar in studying dynamic behaviour of geomaterials.For comparison,the dynamic Brazilian disc(BD)tests were performed using three rock types(e.g.,sandstone,granite and marble)under different strain rates ranging from 10^(−3)∼10^(2) s^(−1).Besides,the Digital Image Correlation(DIC)technique was adopted to measure full-field real-time tensile strain of rocks and demonstrated that tensile crack initiated at the middle part and split the specimen into two similar halves.Effects of specimen size,geometry,loading rate as well as the confining pressure are investigated in detail.The dynamic fracture behaviours,including dynamic tensile strength,tensile strain,time to fracture and dynamic increase factor(DIF),were characterised for the rocks.It is found that dynamic tensile strength of rock minimal dependence on size and geometry but is significantly influenced by loading rate and confinement.It exhibited a linear increase with strain rate(10^(0)∼10^(2) s^(−1))and demonstrated a nonlinear growth with lateral confinement from 0 to 15 MPa.The nonlinear dependency on confinement can be attributed to the restriction imposed on the opening and propagation of tensile cracks due to the presence of confinement.These findings enhance our understanding of the safety aspects associated with underground rock excavations,particularly in situations where considering in-situ stress is crucial for evaluating the dynamic tensile failure of rocks.展开更多
Website fingerprinting (WF) attacks can reveal information about the websites users browse by de-anonymizing encrypted traffic. Traditional website fingerprinting attack models, focusing solely on a single spatial fea...Website fingerprinting (WF) attacks can reveal information about the websites users browse by de-anonymizing encrypted traffic. Traditional website fingerprinting attack models, focusing solely on a single spatial feature, are inefficient regarding training time. When confronted with the concept drift problem, they suffer from a sharp drop in attack accuracy within a short period due to their reliance on extensive, outdated training data. To address the above problems, this paper proposes a parallel website fingerprinting attack (APWF) that incorporates an attention mechanism, which consists of an attack model and a fine-tuning method. Among them, the APWF model innovatively adopts a parallel structure, fusing temporal features related to both the front and back of the fingerprint sequence, along with spatial features captured through channel attention enhancement, to enhance the accuracy of the attack. Meanwhile, the APWF method introduces isomorphic migration learning and adjusts the model by freezing the optimal model weights and fine-tuning the parameters so that only a small number of the target, samples are needed to adapt to web page changes. A series of experiments show that the attack model can achieve 83% accuracy with the help of only 10 samples per category, which is a 30% improvement over the traditional attack model. Compared to comparative modeling, APWF improves accuracy while reducing time costs. After further fine-tuning the freezing model, the method in this paper can maintain the accuracy at 92.4% in the scenario of 56 days between the training data and the target data, which is only 4% less loss compared to the instant attack, significantly improving the robustness and accuracy of the model in coping with conceptual drift.展开更多
文摘针对线控转向(steer by wire, SBW)系统主动转向时面临的系统参数不确定性、轮胎回正力矩阻碍、转向电机电磁特性耦合等非线性干扰问题,提出一种自适应抗扰转角控制策略。采用径向基函数神经网络和鲁棒滑模理论设计外环转角控制器,自适应补偿SBW系统参数不确定性和轮胎回正力矩阻碍。在内环电流控制器中引入线性自抗扰控制应对转向执行电机电磁特性耦合问题,提高SBW系统动态响应性能。仿真和硬件在环试验结果表明,设计的控制策略能够帮助SBW在多种工况中维持转角稳态跟随误差在1.5°内。
基金supported by an Innovation Fund for Medical Sciences of the Chinese Academy of Medical Sciences (Grant No.2019-I2M-2-007).
文摘Objective:Postpartum nutrition plays a critical role in maternal recovery and long-term health.However,the nutritional status of working mothers in the postpartum period remains understudied.This study aimed to assess the dietary quality of postpartum women in urban Beijing,identify occupational-related factors influencing their diet,and explore potential interventions to improve maternal nutrition during the postpartum period.Methods:In this cross-sectional analysis,554 women one year after delivery were recruited from ten community health centers.Sociodemographic,occupational and postpartum care variables were collected via questionnaire.Dietary intake over the preceding year was assessed using a food frequency questionnaire.The modified dietary balance index for postpartum women were used for dietary quality assessment.Results:The study revealed severe dietary imbalances among postpartum women,characterized by excessive consumption of cereals,eggs,and meats,while their intake of vegetables,fruits,and dairy products was inadequate.According to dietary balance index for postpartum women,66.25%of mothers showed varying degrees of excessive intake.45.31%of mothers experienced varying levels of insufficient intake,with only 19.86%of participants having a relatively balanced diet.Occupational differences were observed,with women in the commercial employment group showing higher levels of excessive food intake.The analysis of influencing factors showed that family monthly income,maternity leave,and postpartum care significantly affected the dietary quality.Conclusions:Postpartum women in Beijing experience widespread dietary imbalances,with both excesses and deficiencies.Occupational context and related factors significantly shape diet quality.These findings highlight the need for targeted nutritional interventions tailored to the specific challenges of different occupational groups.
基金supported by the National Key Research and Development Plan of China (2023YFA1802000)the National Natural Science Foundation of China for Distinguished Young Scholars (31925014),the National Natural Science Foundation of China Key Program (32130033),the National Natural Science Foundation of Original Exploratory Program (32350006)+5 种基金the Key Research Program of Frontier Sciences,Chinese Academy of Sciences (ZDBS-LY-SM010)Shanghai Pilot Program for Basic Research-Chinese Academy of Sciences,Shanghai Branch (JCYJ-SHFY-2022-006)Shanghai Science Technology Innovation Action Plan for Basic Research Program (21JC1406300)Haihe laboratory of Cell Ecosystem Innovation Fund (24HHXBSS00011)CAS project for Young Scientists in Basic Research (YSBR-077)supported by Science and Technology Commission of Shanghai Municipality (Shanghai Rising-Star Program,23QA1411300)
文摘Erythroid cells, the predominant circulating blood cells, are essential for oxygen and carbon dioxide transport (Obeagu, 2024).Their production, erythropoiesis, involves the coordinated synthesis of globin chains and heme molecules to assemble hemoglobin(Zhang et al., 2021). The erythroid-specific enzyme δ-aminolevulinate synthase 2 (ALAS2) is a key rate-limiting factor in heme biosynthesis,with its expression increasing in late-stage erythropoiesis to meet heme demands (Sadlon et al., 1999). Zebrafish (Danio rerio) is a well-established model for studying erythropoiesis due to its genetic tractability and optical transparency (Zhang and Hamza, 2019;Zhang et al., 2021). The Tol2-mediated Gal4-UAS system has been widely applied for gene and enhancer trapping in zebrafish (Asakawa and Kawakami, 2009). However, reliable Gal4 enhancer-trap lines for erythropoiesis remain limited. Here, we report a transgenic zebrafish line with erythroid-specific Gal4FF expression under the control of the endogenous alas2 promoter, offering a more precise erythroblast labeling than the gata1a reporter line. This model provides a valuable tool for erythroid-specific investigations of blood flow dynamics and gene function.
基金supported by the National Natural Science Foundation of China(Grant no.52304065)China Postdoctoral Science Foundation(Grant no.2022MD723759).
文摘Taking into account the characteristics of non-Newtonian fluids and the influence of latent heat of wax crystallization,this study establishes physical and mathematical models for the synergy of tubular heating and mechanical stirring during the waxy crude oil heating process.Numerical calculations are conducted using the sliding grid technique and FVM.The focus of this study is on the impact of stirring rate(τ),horizontal deflection angle(θ1),vertical deflection angle(θ2),and stirring diameter(D)on the heating effect of crude oil.Our results show that asτincreases from 200 rpm to 500 rpm and D increases from 400 mm to 600 mm,there is an improvement in the average crude oil temperature and temperature uniformity.Additionally,heating efficiency increases by 0.5%and 1%,while the volume of the low-temperature region decreases by 57.01 m^(3) and 36.87 m3,respectively.Asθ1 andθ2 increase from 0°to 12°,the average crude oil temperature,temperature uniformity,and heating efficiency decrease,while the volume of the low-temperature region remains basically the same.Grey correlation analysis is used to rank the importance of stirring parameters in the following order:τ>θ1>θ2>D.Subsequently,multiple regression analysis is used to quantitatively describe the relationship between different stirring parameters and heat transfer evaluation indices through equations.Finally,based on entropy generation minimization,the stirring parameters with optimal heat transfer performance are obtained when τ=350 rpm,θ1=θ2=0°,and D=500 mm.
基金Supported by Binzhou Social Sciences Planning Project in 2024(24-SKGH-051)Binzhou Comprehensive Experimental Station Project of Shandong Provincial Forage Industry Technology System(SDAIT-23-10).
文摘This paper investigated and analyzed the conservation and utilization of four local livestock breeds in Binzhou City:Wadi Sheep,Bohai Black Cattle,Wudi Donkey,and Lubei White Goat.Shortcomings in the protection and utilization of local germplasm resources were pointed out,and strategies and recommendations were proposed to promote high-quality development of livestock and poultry genetic resources in Binzhou,including building a solid germplasm foundation,standardizing production,and driving innovation.This paper provides references for the conservation,development,and utilization of local genetic resources in Binzhou City.
基金supported by National Nature Science Foundation of China(Nos.92161202 and 22121005)China Postdoctoral Science Foundation(Nos.2023M741814 and 2023M741815)+2 种基金Postdoctoral Fellowship Program of CPSF(No.GZC20231170)Natural Science Foundation of Science&Technology Department of Sichuan Province(No.2023NSFSC110)Research and Innovation Team of China West Normal University(No.KCXTD2023-1)。
文摘Selective catalytic transfer hydrogenation(CTH)of carbonyl compounds to obtain specific alcohols holds significant importance across various fields.Achieving multiple selectivity in CTH is particularly crucial,but full of great challenge.Herein,a cationic In-captured Zr-porphyrin framework(1)with nanosized pores/cages was successfully constructed and showed high structure stability.Catalytic investigations revealed that 1 displayed highly multi-selective CTH of aldehydes and ketones containing both chemo-and size selectivity for the first time.The CTH of aldehydes and ketones exhibited remarkable reductive selectivity of 99%towards C=O bonds into CH–OH in the presence of-NO_(2),-CN and C=C groups.Through tuning the reaction conditions,1 also exhibited highly selective reduction of 97%for-CHO groups in the simultaneous presence of-CHO and-COCH3groups in intra-and intermolecular settings.Remarkably,reductive selectivity towards-CHO group remained prominent among five concurrent unsaturated groups mentioned above.Additionally,the definite pore size of 1 facilitated volume control of substrates,enabling size selectivity.1 as a heterogeneous catalyst was further confirmed by leaching tests,and maintained high activity even after being used for at least six cycles.Mechanistic studies have revealed that Zr6O8clusters served as the catalytic centers and the observed chemoselectivity mainly results from the synergistic effect of distinct metal sites within 1.The heightened selectivity towards-CHO over-COCH_(3)can be attributed to the easier realization of transfer hydrogenation processes for-CHO compared to-COCH_(3).
基金Supported by Binzhou Social Science Planning Project(25-SKGH-063)Shandong Agricultural Innovation Team Project(SDAIT-10-06,SDAIT-23-10).
文摘This paper systematically analyzed the development status of sheep industry in Lubei region,and comprehensively expounded the scale and distribution of key industries,breed resources and genetic characteristics,feeding management status,disease prevention and control and veterinary services,and sheep product processing and sales.The research shows that the sheep industry in Lubei region has formed a certain scale,but there are some problems such as intensified resource and environmental constraints,unreasonable industrial structure,insufficient scientific and technological innovation capacity and market competitiveness to be improved.In view of these problems,this paper put forward some countermeasures and suggestions to promote the high-quality development of the industry,including establishing forage and feed system,promoting the adjustment and optimization of industrial structure,strengthening scientific and technological innovation and talent cultivation and introduction,and enhancing brand influence and market competitiveness,providing useful reference for the sustainable development of sheep industry in Lubei region.
文摘Background:Over the past 15 years,research has emphasized the crucial role of the gut microbiota in metabolism and its potential association with osteoporosis.Given the increasing interest in this area,a bibliometric analysis is essential to comprehensively understand the field.Methods:Literature published between 2009 and 2023 was retrieved from the Web of Science.CiteSpace,a tool for visual analysis,was employed to examine various aspects of the research,including the annual number of publications,contributing institutions,journals,authors,keywords,clusters,hotspots,and emerging frontiers.Results:The analysis included 1,075 articles from 80 countries,283 institutions,and 155 authors,reflecting the rapid growth of research in this field.PEOPLES R CHINA emerged as the most productive country,while the University of California System was the most active institution.Parameswaran,Narayanan had the highest number of publications,and LI JY and OHLSSON C were the most cited authors.Key keywords such as“gut microbiota,”“bone loss,”“bone mineral density,”“inflammation,”and“health”were identified,and keywords with strong citation bursts like“in vitro,”“inflammatory bowel disease,”and“bone mineral density”indicated emerging trends.Conclusion:This bibliometric analysis successfully identified research trends and hotspots,including the fecal microbiome,musculoskeletal studies,and postmenopausal women.Continued research in these areas will enhance our understanding of osteoporosis and may lead to the development of new treatments.The findings offer valuable insights for scholars aiming to conduct in-depth research in this field.
基金funded by the National Natural Science Foundation of China,grant number 52204022Natural Science Foundation of Shandong Province,grant number ZR2022ME152+3 种基金Youth Innovation and Technology Support Program for Shandong Provincial Universities,grant number 2022KJ066National Key Research and Development Program of China,grant number 2021YFE0111400Shandong Provincial Key Research and Development Program(2025TSGCCZZB0419)The Major Special Project for Scientific and Technological Innovation of Dongying City(Science and Technology Development Guidance Plan),grant number 2023ZDJH110.
文摘Gas–liquid two-phase jets exhibit markedly enhanced impact performance due to the violent collapse of entrained bubbles,which generates transient microjets and shock waves.The geometry of the nozzle is a decisive factor in controlling jet formation,flow modulation,and impact efficiency.In this work,the structural optimization of gas–liquid two-phase nozzles was investigated numerically using the Volume of Fluid(VOF).Simulation results show that the aero-shaped nozzle delivers a significantly stronger impact on the target surface than conventional geometries.Specifically,its impact pressure is 21%higher than that of a conical straight nozzle and 37%higher than that of a conical nozzle.The aero nozzle not only increases peak impact pressure but also sustains it over a longer duration,leading to an overall improvement in energy transfer efficiency.Parametric analyses further reveal the key geometric conditions governing performance.When the nozzle curvature is set to 0.01,the jet achieves a higher and more stable surface pressure profile,maintaining elevated impact for a prolonged period.At an aspect ratio of 15,the jet exhibits pronounced pulsation under high pressure,thereby enhancing impact intensity.The contraction ratio exerts a non-monotonic influence:as it increases,impact pressure initially rises and subsequently declines,with an optimal value of 4 yielding the highest and most persistent impact pressure.Likewise,when the ratio of inlet length to outlet diameter is 2.5,the jet demonstrates the strongest impact on the target surface.
基金Supported by the Natural Science of Minhang District of Shanghai,No.2023MH2085.
文摘BACKGROUND Sepsis-induced intestinal injury disrupts barrier function and exacerbates systemic inflammation,contributing to high mortality.AIM To investigate the mechanism by which sphinganine protects against sepsisinduced intestinal injury,focusing on macrophage polarization and toll like receptor 2(TLR2)/nuclear factor kappa-B(NF-κB)signaling.METHODS A cecal ligation and puncture sepsis model was established in mice(n=20/group).Treatments included sphinganine(15 mg/kg)and a TLR2 agonist[fibroblast-stimulating lipopeptide-1(FSL-1),10μg/kg].Serum markers[diamine oxidase(DAO),interleukin(IL)-1β,tumor necrosis factor(TNF)-α,IL-6]were measured by enzyme-linked immunosorbent assay.Intestinal injury and macrophage polarization[cluster of differentiation(CD)86^(+)M1,CD206^(+)M2]were assessed via hematoxylin and eosin and immunofluorescence staining.Proteomic analysis,molecular docking,and Western blot were used to evaluate TLR2/NF-κB signaling.Data were analyzed by analysis of variance and t-test.RESULTS Sphinganine significantly reduced serum levels of DAO(P<0.05),IL-1β,TNF-α,and IL-6(P<0.05),preserved intestinal crypt structure,and enhanced tight junction protein zonula occludens-1 expression.It promoted a shift from M1(CD86^(+))to M2(CD206^(+))macrophages.Proteomics identified TLR2 as the most differentially expressed protein,and molecular docking confirmed strong binding between sphinganine and TLR2(-4.3 kcal/mol).Sphinganine downregulated TLR2 and phosphorylated-NF-κB p65 expression(P<0.05),effects reversed by FSL-1.Total NF-κB p65 levels remained unchanged.CONCLUSION Sphinganine protects against sepsis-induced intestinal injury by inhibiting TLR2/NF-κB signaling,modulating macrophage polarization toward the M2 phenotype,and preserving intestinal barrier integrity.
基金Research on Surgical Strategies for the Correction of Pectus Excavatum in Children via an Extrapleural Approach(Project No.:20220404021010)。
文摘Objective:To investigate the clinical efficacy and safety of the extrapleural approach versus the traditional intrathoracic approach in minimally invasive correction of pectus excavatum in children,providing a more scientific basis for selecting a more appropriate surgical method in clinical practice.Methods:This study included 50 children who underwent pectus excavatum correction at Harbin Children’s Hospital from January 2023 to January 2025.All patients were divided into two groups based on surgical approach:the observation group(n=26)and the control group(n=24).Children in the observation group underwent correction surgery via an extrapleural approach,while those in the control group underwent correction surgery via the traditional intrathoracic approach.Both groups underwent Nuss bar placement surgery under thoracoscopic guidance.Intraoperative indicators were compared between the two groups,including operative time,blood loss,pain scores at 24 and 48 hours postoperatively,hospital stay duration,thoracic correction outcomes,and the incidence of complications during a 6-month postoperative follow-up.Results:The intraoperative blood loss in the observation group was significantly lower than that in the control group(p<0.05),and the pain scores at 24 and 28 hours postoperatively were also significantly lower(p<0.05).The improvement in thoracic index postoperatively was relatively similar between the two groups,with no statistically significant difference(p>0.05).During the 6-month postoperative follow-up period,no complications such as pneumothorax,hemothorax,pleural effusion,plate displacement,or infection occurred in the observation group,whereas the overall complication rate in the control group was 25%,showing a significant difference(p<0.05).Conclusion:The extrapleural approach for corrective surgery can ensure the efficacy of thoracic deformity correction while reducing intraoperative blood loss,lowering the incidence of complications,alleviating postoperative pain,and accelerating recovery.It is a safe and effective approach for minimally invasive Nuss correction of pediatric pectus excavatum.
基金supported by the National Key Research and Development Program of China(2023YFF1103802)。
文摘The anti-inflammatory properties of silkworm pupa peptide(SPP)have been recognized for their potential benefits in colitis treatment.However,the underlying mechanism of SPP in colitis animal models remains unclear.The objective of our work was to investigate the improving effect and the mechanism of action of SPP on a mouse model of dextran sulfate sodium(DSS)-induced colitis.The findings suggested that SPP effectively eased ulcerative colitis(UC)symptoms in mice by decreasing disease activity index,ameliorating histopathological injury,and decreasing serum and colonic markers of inflammation.In addition,our research findings demonstrated that SPP restored intestinal barrier function by increasing the production of tight junction proteins such as zonula occludens-1(ZO-1),claudin-1,claudin-3,occludin,and adherens junction protein E-cadherin1.Further,SPP supplementation enhanced the concentration of short-chain fatty acids and positively altered the makeup of the gut bacteria in the mice's gut.These findings underscore SPP's ability to slow the progression of colitis and point to its possible use as a functional component in dietary supplements for the prevention of early-stage colitis.
基金supported by the National Defense Basic Scientific Research Programof China under grant No.JCKY2023602C026.
文摘Network intrusion detection systems(IDS)are a prevalent method for safeguarding network traffic against attacks.However,existing IDS primarily depend on machine learning(ML)models,which are vulnerable to evasion through adversarial examples.In recent years,the Wasserstein Generative Adversarial Network(WGAN),based on Wasserstein distance,has been extensively utilized to generate adversarial examples.Nevertheless,several challenges persist:(1)WGAN experiences the mode collapse problem when generating multi-category network traffic data,leading to subpar quality and insufficient diversity in the generated data;(2)Due to unstable training processes,the authenticity of the data produced by WGAN is often low.This study improves WGAN to address these issues and proposes a new adversarial sample generation algorithm called Distortion Enhanced Multi-Generator Generative Adversarial Network(DEMGAN).DEMGAN effectively evades ML-based IDS by proficiently obfuscating network traffic data samples.We assess the efficacy of our attack method against five ML-based IDS using two public datasets.The results demonstrate that our method can successfully bypass IDS,achieving average evasion rates of 97.42%and 87.51%,respectively.Furthermore,empirical findings indicate that retraining the IDS with the generated adversarial samples significantly bolsters the system’s capability to detect adversarial samples,resulting in an average recognition rate increase of 86.78%.This approach not only enhances the performance of the IDS but also strengthens the network’s resilience against potential threats,thereby optimizing network security measures.
基金supported by the National Natural Science Foundation of China(Grant No.U2241263)the fellowship of China Postdoctoral Science Foundation(Grant No.2024M750310).
文摘Numerical simulation plays an important role in the dynamic analysis of multibody system.With the rapid development of computer science,the numerical solution technology has been further developed.Recently,data-driven method has become a very popular computing method.However,due to lack of necessary mechanism information of the traditional pure data-driven methods based on neural network,its numerical accuracy cannot be guaranteed for strong nonlinear system.Therefore,this work proposes a mechanism-data hybrid-driven strategy for solving nonlinear multibody system based on physics-informed neural network to overcome the limitation of traditional data-driven methods.The strategy proposed in this paper introduces scaling coefficients to introduce the dynamic model of multibody system into neural network,ensuring that the training results of neural network conform to the mechanics principle of the system,thereby ensuring the good reliability of the data-driven method.Finally,the stability,generalization ability and numerical accuracy of the proposed method are discussed and analyzed using three typical multibody systems,and the constrained default situations can be controlled within the range of 10^(-2)-10^(-4).
基金supported by theHigher Education Research Project of Jilin Province:JGJX24C118the National Defense Basic Scientific Research Program of China(No.JCKY2023602C026).
文摘With the rapid proliferation of Internet ofThings(IoT)devices,ensuring their communication security has become increasingly important.Blockchain and smart contract technologies,with their decentralized nature,provide strong security guarantees for IoT.However,at the same time,smart contracts themselves face numerous security challenges,among which reentrancy vulnerabilities are particularly prominent.Existing detection tools for reentrancy vulnerabilities often suffer from high false positive and false negative rates due to their reliance on identifying patterns related to specific transfer functions.To address these limitations,this paper proposes a novel detection method that combines pattern matching with deep learning.Specifically,we carefully identify and define three common patterns of reentrancy vulnerabilities in smart contracts.Then,we extract key vulnerability features based on these patterns.Furthermore,we employ a Graph Attention Neural Network to extract graph embedding features from the contract graph,capturing the complex relationships between different components of the contract.Finally,we use an attention mechanism to fuse these two sets of feature information,enhancing the weights of effective information and suppressing irrelevant information,thereby significantly improving the accuracy and robustness of vulnerability detection.Experimental results demonstrate that our proposed method outperforms existing state-ofthe-art techniques,achieving a 3.88%improvement in accuracy compared to the latest vulnerability detection model AME(Attentive Multi-Encoder Network).This indicates that our method effectively reduces false positives and false negatives,significantly enhancing the security and reliability of smart contracts in the evolving IoT ecosystem.
基金supported by the Australian Research Council(LE150100058)the Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering(Z020002)State Key Laboratory of Coal Mine Disaster Dynamics and Control.The specimens were scanned at the Imaging and Medical beamline(IMBL)under the Australian Synchrotron projects(NO:M15862 and M14428).
文摘Tensile cracking is a predominant mode of failure in rocks within underground resource excavation and engineering structures,where rocks are frequently subjected to dynamic disturbances while simultaneously experiencing in-situ stresses.This paper proposes a new dynamic split tension setup utilising a cubic specimen to investigate the dynamic behaviour of rocks across various tensile strain rates and confining pressures.The objective is to extend the applicability of the triaxial Hopkinson bar in studying dynamic behaviour of geomaterials.For comparison,the dynamic Brazilian disc(BD)tests were performed using three rock types(e.g.,sandstone,granite and marble)under different strain rates ranging from 10^(−3)∼10^(2) s^(−1).Besides,the Digital Image Correlation(DIC)technique was adopted to measure full-field real-time tensile strain of rocks and demonstrated that tensile crack initiated at the middle part and split the specimen into two similar halves.Effects of specimen size,geometry,loading rate as well as the confining pressure are investigated in detail.The dynamic fracture behaviours,including dynamic tensile strength,tensile strain,time to fracture and dynamic increase factor(DIF),were characterised for the rocks.It is found that dynamic tensile strength of rock minimal dependence on size and geometry but is significantly influenced by loading rate and confinement.It exhibited a linear increase with strain rate(10^(0)∼10^(2) s^(−1))and demonstrated a nonlinear growth with lateral confinement from 0 to 15 MPa.The nonlinear dependency on confinement can be attributed to the restriction imposed on the opening and propagation of tensile cracks due to the presence of confinement.These findings enhance our understanding of the safety aspects associated with underground rock excavations,particularly in situations where considering in-situ stress is crucial for evaluating the dynamic tensile failure of rocks.
基金supported by the National Defense Basic Scientific Research Program of China(No.JCKY2023602C026)the funding of Key Laboratory of Mobile Application Innovation and Governance Technology,Ministry of Industry and Information Technology(2023IFS080601-K).
文摘Website fingerprinting (WF) attacks can reveal information about the websites users browse by de-anonymizing encrypted traffic. Traditional website fingerprinting attack models, focusing solely on a single spatial feature, are inefficient regarding training time. When confronted with the concept drift problem, they suffer from a sharp drop in attack accuracy within a short period due to their reliance on extensive, outdated training data. To address the above problems, this paper proposes a parallel website fingerprinting attack (APWF) that incorporates an attention mechanism, which consists of an attack model and a fine-tuning method. Among them, the APWF model innovatively adopts a parallel structure, fusing temporal features related to both the front and back of the fingerprint sequence, along with spatial features captured through channel attention enhancement, to enhance the accuracy of the attack. Meanwhile, the APWF method introduces isomorphic migration learning and adjusts the model by freezing the optimal model weights and fine-tuning the parameters so that only a small number of the target, samples are needed to adapt to web page changes. A series of experiments show that the attack model can achieve 83% accuracy with the help of only 10 samples per category, which is a 30% improvement over the traditional attack model. Compared to comparative modeling, APWF improves accuracy while reducing time costs. After further fine-tuning the freezing model, the method in this paper can maintain the accuracy at 92.4% in the scenario of 56 days between the training data and the target data, which is only 4% less loss compared to the instant attack, significantly improving the robustness and accuracy of the model in coping with conceptual drift.
