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基于VIP/cAMP/Epac信号通路探讨星状神经节埋线对哮喘模型大鼠的作用机制
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作者 张莹 程燕 +1 位作者 董佳雯 王珏 《江苏中医药》 2026年第1期72-76,共5页
目的:探讨星状神经节埋线通过血管活性肠肽(VIP)/环腺苷酸(cAMP)/cAMP直接激活的交换蛋白(Epac)信号通路对哮喘模型大鼠的干预机制。方法:将40只雄性SD大鼠随机分为空白组、模型组、星状神经节埋线组、星状神经节阻滞组和布地奈德组,每... 目的:探讨星状神经节埋线通过血管活性肠肽(VIP)/环腺苷酸(cAMP)/cAMP直接激活的交换蛋白(Epac)信号通路对哮喘模型大鼠的干预机制。方法:将40只雄性SD大鼠随机分为空白组、模型组、星状神经节埋线组、星状神经节阻滞组和布地奈德组,每组8只。除空白组外,其余4组大鼠采用卵清蛋白(OVA)和氢氧化铝佐剂致敏结合OVA雾化激发的方法建立哮喘大鼠模型。自入组日起,造模大鼠于实验第0日、第7日,每只大鼠腹腔注射10% OVA混悬液1 mL以致敏,第15日起连续7 d每日雾化吸入5% OVA生理盐水溶液进行哮喘激发,所有大鼠均造模成功。实验第15日,星状神经节埋线组大鼠予C7椎体横突处穴位埋线;星状神经节阻滞组大鼠予星状神经节(C7椎体横突处)罗哌卡因注射,每日1次,连续7 d;布地奈德组大鼠予布地奈德雾化,每日1次,连续7 d。末次给药24 h后,麻醉大鼠取材进行指标检测。采用苏木精-伊红(HE)染色法观察各组大鼠肺组织病理变化,酶联免疫吸附(ELISA)法检测各组大鼠血清和肺泡灌洗液中白细胞介素5(IL-5)以及肺组织匀浆和血清中cAMP水平,蛋白质印迹法(Western blot法)检测各组大鼠肺组织VIP、Epac表达水平。结果:HE染色结果显示,模型组大鼠局部肺泡塌陷或间隔显著增厚,支气管周围可见大量炎性细胞浸润;各治疗组大鼠肺泡结构、支气管周围炎性细胞浸润均有明显改善,其中布地奈德组和星状神经节埋线组大鼠肺泡结构较完整,支气管周围炎性细胞浸润情况改善明显。模型组大鼠血清和肺泡灌洗液IL-5水平均明显高于空白组(P<0.01),血清和肺组织匀浆cAMP水平、肺组织VIP及Epac蛋白相对表达量均明显低于空白组(P<0.01);各治疗组大鼠上述指标均较模型组有明显改善(P<0.05,P<0.01);星状神经节埋线组大鼠上述指标与布地奈德组、星状神经节阻滞组比较,差异均无统计学意义(P>0.05)。结论:星状神经节埋线可显著改善哮喘模型大鼠气道炎症,减轻肺组织病理损伤,其机制可能与激活VIP/cAMP/Epac信号通路和降低炎性因子水平有关。 展开更多
关键词 哮喘 星状神经节 穴位埋线 vip/cAMP/Epac信号通路 白细胞介素5
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Nonlocal Boundary Value Problems for Nonlinear Fractional Differential Equations with a Disturbance Parameter on the Infinite Interval
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作者 ZHENG Yanping YANG Hui WANG Wenxia 《应用数学》 北大核心 2026年第2期360-372,共13页
This paper is concerned with a class of nonlinear fractional differential equations with a disturbance parameter in the integral boundary conditions on the infinite interval.By using Guo-Krasnoselskii fixed point theo... This paper is concerned with a class of nonlinear fractional differential equations with a disturbance parameter in the integral boundary conditions on the infinite interval.By using Guo-Krasnoselskii fixed point theorem,fixed point index theory and the analytic technique,we give the bifurcation point of the parameter which divides the range of parameter for the existence of at least two,one and no positive solutions for the problem.And,by using a fixed point theorem of generalized concave operator and cone theory,we establish the maximum parameter interval for the existence of the unique positive solution for the problem and show that such a positive solution continuously depends on the parameter.In the end,some examples are given to illustrate our main results. 展开更多
关键词 Boundary value problem Disturbance parameter Infinite interval Bifurcation point CONE
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Mindfulness and internalizing/externalizing problems among adolescents:Ethnicity moderation and psychological capital mediation
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作者 Jia Wu Wei Luo +4 位作者 Qianguo Xiao Qinhong Xie Xiaodong Li Taiyong Bi Hui Kou 《Journal of Psychology in Africa》 2026年第1期97-106,共10页
This study examines the mediating role of positive psychological capital and the moderating role of ethnicity in the relationship between mindfulness and internalizing/externalizing problems among adolescents.The stud... This study examines the mediating role of positive psychological capital and the moderating role of ethnicity in the relationship between mindfulness and internalizing/externalizing problems among adolescents.The study sample comprized Chinese adolescents(N=637 ethnic minority;females=40.97%,meam age=12.68,SD=0.49 years;N=636 Han;females=49.06%,mean age=12.71,SD=0.47 years).The participants completed the Child and Adolescent Mindfulness Measure,the Positive Psycap Questionnaire,and the Youth Self-Report.Results from the moderated mediation analysis showed mindfulness was negatively associated with both internalizing and externalizing problems.Ethnicity moderated the relationship between mindfulness and internalizing problems to be stronger for Han adolescents compared to ethnic minority adolescents.Psychological capital mediated the relationship between mindfulness and internalizing problems in both groups,with a negative direction.Findings support the Conservation of Resources theory and highlight mindfulness as a personal resource fostering adolescent well-being in multicultural contexts. 展开更多
关键词 Ethnic minority adolescent MINDFULNESS positive psychological capital internalizing problems externalizing problems
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Bifurcation and Stability of Nonlinear Steklov Problems on the Unit Disk
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作者 Qingbo LIU Ruihao LIU Yingxin SUN 《Journal of Mathematical Research with Applications》 2026年第2期251-262,共12页
This paper is concerned with the following nonlinear Steklov problemΔu=0 in D,∂vu=λf(u)on∂D,where D is the unit disk in the plane,∂v denotes the unit outward normal derivative.For each k∈N,under some natural condit... This paper is concerned with the following nonlinear Steklov problemΔu=0 in D,∂vu=λf(u)on∂D,where D is the unit disk in the plane,∂v denotes the unit outward normal derivative.For each k∈N,under some natural conditions on f,using the Crandall-Rabinowitz bifurcation theorem,we obtain a bifurcation curve emanating from(k,0).Furthermore,we also analyze the local structure of bifurcation curves and stability of solutions on them.Specifically,our results indicate the bifurcation is critical for each k and is subcritical(supercritical)if f'''(0)>0(f'''(0)<0). 展开更多
关键词 teklov eigenvalue BIFURCATION STABILITY nonlinear boundary problem
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VIP真空绝热板企业积极应对成本挑战,助力冰箱行业节能升级
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作者 邓雅静 《电器》 2026年第3期42-42,共1页
GB 12021.2-2025《家用电冰箱耗电量限定值及能效等级》即将正式实施,具有极低导热系数的VIP真空绝热板或将迎来较大的市场机会,但现阶段依然面临成本较高的挑战。机会和挑战面前,VIP真空绝热板企业一方面通过技术创新降低产品成本,另... GB 12021.2-2025《家用电冰箱耗电量限定值及能效等级》即将正式实施,具有极低导热系数的VIP真空绝热板或将迎来较大的市场机会,但现阶段依然面临成本较高的挑战。机会和挑战面前,VIP真空绝热板企业一方面通过技术创新降低产品成本,另一方面拓展更多新业务领域,打造多元化赛道。 展开更多
关键词 节能升级 冰箱行业 vip真空绝热板 成本挑战
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The Curvilinear Relationship between Maternal-Parenting Stress and Adolescent Internalizing-Problems:Family Socioeconomic-Status and Adolescent Gender’s Moderating Roles
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作者 Xiaoting Hou Jingjing Zhao +2 位作者 Yuxin Shi Yuhua Li Shufen Xing 《International Journal of Mental Health Promotion》 2026年第3期26-37,共12页
Background:The growing parenting stress among Chinese mothers in recent years raises concerns about its impact on adolescent internalizing problems.The purpose of this study was to examine the curvilinear relationship... Background:The growing parenting stress among Chinese mothers in recent years raises concerns about its impact on adolescent internalizing problems.The purpose of this study was to examine the curvilinear relationship between maternal parenting stress and internalizing problems in adolescents,and further explore the moderating effects of family socioeconomic status(SES)and adolescent gender.Methods:Data were collected from 405 mothers and adolescents(203 boys,Meanage=12.23)across five cities(Beijing,Hebei,Shanxi,Shenzhen,and Shandong)in China,who completed self-report measures of maternal parenting stress and internalizing problems.Descriptive statistics and multiple regression analyses were conducted using SPSS 27.0.Results:Multiple regression analyses indicated that the association between maternal parenting stress2 and adolescents’internalizing problems was moderated by the interaction between gender and SES(b=−0.03,p<0.01).Specifically,a significant U-shaped relationship was observed among high-SES boys(b=0.12,t=3.89,p<0.001),with internalizing problems peaking at both low and high levels of maternal parenting stress,whereas the moderating effect of SES was not significant among girls.Conclusion:The study highlights that moderate maternal parenting stress is associated with lower internalizing problems among adolescents,particularly among high-SES boys,indicating that interventions should consider the optimal balance of parental stress and account for family socioeconomic and adolescent gender differences. 展开更多
关键词 Maternal parenting stress internalizing problems family socioeconomic status GENDER
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Somatization and Eating Problems in Adolescents in Residential Care: The Influence of Relational Trauma, Attachment, Gender, and Personal Resources
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作者 Laura Lacomba-Trejo Francisco González-Sala +1 位作者 Sandra Simó Florencia Talmón-Knuser 《International Journal of Mental Health Promotion》 2026年第3期38-58,共21页
Backgrounds:Somatization and eating-related problems in adolescents living in residential care may be shaped by the interplay of risk and protective factors,including gender,relational trauma,attachment patterns,emoti... Backgrounds:Somatization and eating-related problems in adolescents living in residential care may be shaped by the interplay of risk and protective factors,including gender,relational trauma,attachment patterns,emotional intelligence,and perceived social support.This study examined how gender,relational trauma,attachment dimensions,resilience,and emotional intelligence contribute to the presence of somatic and eating difficulties in this population.Methods:The sample included 46 adolescents(63%female;ages 12–17,Mean=14.85,Standard Deviation(SD)=1.49)residing in child protection institutions in Uruguay.Participants completed self-report measures assessing childhood relational trauma(CaMir),attachment dimensions(anxiety and avoidance),resilience,emotional intelligence(adaptability and stress management),social support(MOS),and psychosocial adjustment(SENA subscales of somatization and eating problems).Using a fuzzy-set Qualitative Comparative Analysis(fsQCA)approach,distinct configurations of risk and protective factors associated with elevated levels of somatization and eating problems were identified.Results:Relational trauma and attachment anxiety showed moderate associations with both somatization and eating problems(r=0.52–0.57,p<0.01),whereas stress management was negatively associated with both outcomes(r=−0.37 to−0.47,p<0.05).FsQCA revealed multiple configurations of risk and protective factors explaining 81–90%of cases,with solution consistencies ranging from 0.83 to 0.87.Results suggest that relational trauma and attachment anxiety are key risk conditions,whereas resilience,emotional regulation,and perceived social support function as protective factors.Conclusions:Findings highlight the importance of considering multifactorial patterns of vulnerability and protection rather than single predictors and underscore the need for tailored interventions that strengthen resilience and emotional skills while addressing the impact of early relational trauma. 展开更多
关键词 Residential care SOMATIZATION eating problems relational trauma RESILIENCE emotional intelligence social support
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NONLINEAR RIEMANN AND HILBERT BOUNDARY VALUE PROBLEMS WITH SQUARE ROOTS IN VARIABLE EXPONENT SPACES
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作者 Yajun Hu Fuli He 《Acta Mathematica Scientia》 2026年第1期1-18,共18页
In this paper,we study the nonlinear Riemann boundary value problem with square roots that is represented by a Cauchy-type integral with kernel density in variable exponent Lebesgue spaces.We discuss the odd-order zer... In this paper,we study the nonlinear Riemann boundary value problem with square roots that is represented by a Cauchy-type integral with kernel density in variable exponent Lebesgue spaces.We discuss the odd-order zero-points distribution of the solutions and separate the single valued analytic branch of the solutions with square roots,then convert the problem to a Riemann boundary value problem in variable exponent Lebesgue spaces and discuss the singularity of solutions at individual zeros belonging to curve.We consider two types of cases those where the coefficient is Hölder and those where it is piecewise Hölder.Then we solve the Hilbert boundary value problem with square roots in variable exponent Lebesgue spaces.By discussing the distribution of the odd-order zero-points for solutions and the method of symmetric extension,we convert the Hilbert problem to a Riemann boundary value problem.The equivalence of the transformation is discussed.Finally,we get the solvable conditions and the direct expressions of the solutions in variable exponent Lebesgue spaces. 展开更多
关键词 boundary value problem Cauchy-type integral variable exponent spaces non-linearity piecewise Lyapunov curve
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Design and Validation of Zeroing Neural Network With Active Noise Rejection Capability for Time-Varying Problems Solving
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作者 Yilin Shang Wenbo Zhang +1 位作者 Dongsheng Guo Shan Xue 《CAAI Transactions on Intelligence Technology》 2026年第1期256-266,共11页
Recently,the zeroing neural network(ZNN)has demonstrated remarkable effectiveness in tackling time-varying problems,delivering robust performance across both noise-free and noisy environments.However,existing ZNN mode... Recently,the zeroing neural network(ZNN)has demonstrated remarkable effectiveness in tackling time-varying problems,delivering robust performance across both noise-free and noisy environments.However,existing ZNN models are limited in their ability to actively suppress noise,which constrains their robustness and precision in solving time-varying problems.This paper introduces a novel active noise rejection ZNN(ANR-ZNN)design that enhances noise suppression by integrating computational error dynamics and harmonic behaviour.Through rigorous theoretical analysis,we demonstrate that the proposed ANR-ZNN maintains robust convergence in computational error performance under environmental noise.As a case study,the ANR-ZNN model is specifically applied to time-varying matrix inversion.Comprehensive computer simulations and robotic experiments further validate the ANR-ZNN's effectiveness,emphasising the proposed design's superiority and potential for solving time-varying problems. 展开更多
关键词 active noise rejection matrix inversion robot application time-varying problems zeroing neural network
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Cooperative Metaheuristics with Dynamic Dimension Reduction for High-Dimensional Optimization Problems
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作者 Junxiang Li Zhipeng Dong +2 位作者 Ben Han Jianqiao Chen Xinxin Zhang 《Computers, Materials & Continua》 2026年第1期1484-1502,共19页
Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when ta... Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when tackling high-dimensional optimization challenges.To effectively address these challenges,this study introduces cooperative metaheuristics integrating dynamic dimension reduction(DR).Building upon particle swarm optimization(PSO)and differential evolution(DE),the proposed cooperative methods C-PSO and C-DE are developed.In the proposed methods,the modified principal components analysis(PCA)is utilized to reduce the dimension of design variables,thereby decreasing computational costs.The dynamic DR strategy implements periodic execution of modified PCA after a fixed number of iterations,resulting in the important dimensions being dynamically identified.Compared with the static one,the dynamic DR strategy can achieve precise identification of important dimensions,thereby enabling accelerated convergence toward optimal solutions.Furthermore,the influence of cumulative contribution rate thresholds on optimization problems with different dimensions is investigated.Metaheuristic algorithms(PSO,DE)and cooperative metaheuristics(C-PSO,C-DE)are examined by 15 benchmark functions and two engineering design problems(speed reducer and composite pressure vessel).Comparative results demonstrate that the cooperative methods achieve significantly superior performance compared to standard methods in both solution accuracy and computational efficiency.Compared to standard metaheuristic algorithms,cooperative metaheuristics achieve a reduction in computational cost of at least 40%.The cooperative metaheuristics can be effectively used to tackle both high-dimensional unconstrained and constrained optimization problems. 展开更多
关键词 Dimension reduction modified principal components analysis high-dimensional optimization problems cooperative metaheuristics metaheuristic algorithms
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Neural boundary shape functions in physics-informed neural networks for discontinuous and high-frequency problems
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作者 P.T.NGUYEN K.A.LUONG J.H.LEE 《Applied Mathematics and Mechanics(English Edition)》 2026年第2期423-442,共20页
Physics-informed neural networks(PINNs)have been shown as powerful tools for solving partial differential equations(PDEs)by embedding physical laws into the network training.Despite their remarkable results,complicate... Physics-informed neural networks(PINNs)have been shown as powerful tools for solving partial differential equations(PDEs)by embedding physical laws into the network training.Despite their remarkable results,complicated problems such as irregular boundary conditions(BCs)and discontinuous or high-frequency behaviors remain persistent challenges for PINNs.For these reasons,we propose a novel two-phase framework,where a neural network is first trained to represent shape functions that can capture the irregularity of BCs in the first phase,and then these neural network-based shape functions are used to construct boundary shape functions(BSFs)that exactly satisfy both essential and natural BCs in PINNs in the second phase.This scheme is integrated into both the strong-form and energy PINN approaches,thereby improving the quality of solution prediction in the cases of irregular BCs.In addition,this study examines the benefits and limitations of these approaches in handling discontinuous and high-frequency problems.Overall,our method offers a unified and flexible solution framework that addresses key limitations of existing PINN methods with higher accuracy and stability for general PDE problems in solid mechanics. 展开更多
关键词 physics-informed neural network(PINN) boundary shape function(BSF) strong-form approach energy approach DISCONTINUITY high-frequency problem
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Embodied-Intelligence Power Industrial Control Systems:Architecture Design,Key Scientific Problems,and Research Recommendations
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作者 Tingjun Zhang Dong Yue 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期239-242,共4页
THE power industrial control system(power ICS)is thecore infrastructure that ensures the safe,stable,and efficient operation of power systems.Its architecture typi-cally adopts a hierarchical and partitioned end-edge-... THE power industrial control system(power ICS)is thecore infrastructure that ensures the safe,stable,and efficient operation of power systems.Its architecture typi-cally adopts a hierarchical and partitioned end-edge-cloud collaborative design.However,the large-scale integration ofdistributed renewable energy resources,coupled with the extensivedeployment of sensing and communication devices,has resulted inthe new-type power system characterized by dynamic complexityand high uncertainty[1]-[4]. 展开更多
关键词 power system embodied intelligence power industrial control system power architecture design key scientific problems power industrial control systems sensing communication deviceshas renewable energy resourcescoupled
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助阳通便汤治疗功能性便秘临床观察及对便秘模型小鼠结肠组织VIP的影响 被引量:2
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作者 王璐 隋楠 《中华中医药学刊》 北大核心 2025年第4期66-71,I0016,共7页
目的观察助阳通便汤对功能性便秘(脾肾阳虚证)患者的临床疗效和患者血清P物质(substance P,SP)、血管活性肠肽(vasoactive intestinal peptide,VIP)含量的影响,以及其对便秘模型小鼠结肠组织病理及VIP表达的影响。方法(1)将66例符合功... 目的观察助阳通便汤对功能性便秘(脾肾阳虚证)患者的临床疗效和患者血清P物质(substance P,SP)、血管活性肠肽(vasoactive intestinal peptide,VIP)含量的影响,以及其对便秘模型小鼠结肠组织病理及VIP表达的影响。方法(1)将66例符合功能性便秘诊断,且中医证型为脾肾阳虚证的患者,用随机数字表法进行分组,其中治疗组(33例)、对照组(33例),治疗组助阳通便汤130 mL日2次口服,对照组乳果糖15 mL日2次口服,均治疗2周。比较两组患者用药前后便秘症状评分、粪便性状评分、中医证候评分及血清SP、VIP含量。(2)将18只雄性BALB/c小鼠依据随机数字表法分为KB组(空白对照组)、MX组(模型组)、ZY组(助阳通便汤组)3组,每组6只,以复方地芬诺酯片混悬液80 mg/kg灌胃的方法进行造模。ZY组给予助阳通便汤0.2 mL/10 g连续2周灌胃,结束后取材,观察各组小鼠结肠组织病理及VIP免疫组化表达。结果(1)治疗后两组患者便秘症状及粪便性状的评分均比治疗前显著提高(P<0.05);治疗组中医证候评分差异有统计学意义(P<0.05);治疗组患者血清SP含量高于对照组(P<0.05),血清VIP含量低于对照组(P<0.05)。治疗组有效率90.0%,对照组有效率73.3%(P<0.05)。(2)与模型组(MX组)小鼠比较,助阳通便汤组(ZY组)小鼠结肠组织中VIP阳性表达细胞分布相对较密集,阳性细胞数量较多(P<0.05)。结论助阳通便汤对功能性便秘(脾肾阳虚证)患者的临床症状及中医证候有较好地改善,并且对患者血清SP、VIP含量有干预作用;助阳通便汤调控便秘模型小鼠结肠组织VIP含量是其治疗功能性便秘的作用机制之一。 展开更多
关键词 助阳通便汤 功能性便秘 脾肾阳虚型 SP vip
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肥胖型PCOS不孕症患者血清铁代谢指标、miR-29a、VIP的变化及临床意义
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作者 王屹雯 任宝红 +1 位作者 周亚红 温丽娜 《中南医学科学杂志》 2025年第3期418-421,共4页
目的探讨肥胖型多囊卵巢综合征(PCOS)不孕症患者血清铁代谢指标、miR-29a、血管活性肠肽(VIP)的变化及其临床意义。方法选取PCOS不孕症患者130例,按照是否肥胖分为肥胖组和非肥胖组;按照随访结果,肥胖组分为促排妊娠成功组和失败组,或... 目的探讨肥胖型多囊卵巢综合征(PCOS)不孕症患者血清铁代谢指标、miR-29a、血管活性肠肽(VIP)的变化及其临床意义。方法选取PCOS不孕症患者130例,按照是否肥胖分为肥胖组和非肥胖组;按照随访结果,肥胖组分为促排妊娠成功组和失败组,或者妊娠结局不良组和良好组。比较各组血清铁蛋白、miR-29a、VIP水平,采用ROC曲线分析铁蛋白、miR-29a及VIP的预测价值。结果肥胖组铁蛋白、miR-29a高于非肥胖组,VIP低于非肥胖组(P<0.05)。失败组铁蛋白、miR-29a高于成功组,VIP低于成功组(P<0.05)。不良组铁蛋白、miR-29a高于良好组,VIP低于良好组(P<0.05)。铁蛋白、miR-29a及VIP对促排妊娠失败具有良好的预测价值,铁蛋白、miR-29a对不良妊娠结局具有良好的预测价值(P<0.05)。结论PCOS不孕症患者血清铁蛋白、miR-29a升高,VIP降低,且与促排妊娠、妊娠结局有明显关系。 展开更多
关键词 肥胖型PCOS 不孕症 铁蛋白 miR-29a vip 妊娠结局
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红景天苷通过VIP-cAMP通路对大鼠腮腺放射性损伤的改善作用及机制
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作者 张春英 阴广维 +4 位作者 陈红 尤鸣达 刘金凤 张亚昆 胡耀杰 《中国药房》 北大核心 2025年第22期2796-2801,共6页
目的探讨红景天苷对大鼠腮腺放射性损伤的改善作用及机制。方法将大鼠随机分为正常组、放射组、红景天苷低剂量(红景天苷-L,50 mg/kg)组、红景天苷高剂量(红景天苷-H,100 mg/kg)组、红景天苷-H+抑制剂(100 mg/kg红景天苷+0.1μmol/kg H-... 目的探讨红景天苷对大鼠腮腺放射性损伤的改善作用及机制。方法将大鼠随机分为正常组、放射组、红景天苷低剂量(红景天苷-L,50 mg/kg)组、红景天苷高剂量(红景天苷-H,100 mg/kg)组、红景天苷-H+抑制剂(100 mg/kg红景天苷+0.1μmol/kg H-89)组,每组10只。除正常组外,其余各组大鼠通过放射线照射构建腮腺放射性损伤模型。各组大鼠腹腔注射相应药物或生理盐水,每日1次,连续40 d。末次给药后,检测血清中活性氧(ROS)、环磷酸腺苷(cAMP)、超氧化物歧化酶(SOD)、淀粉酶水平,观察腮腺组织病理学变化,检测腮腺组织细胞凋亡率和其中B细胞淋巴瘤2(Bcl-2)及其相关X蛋白(Bax)表达情况,白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)mRNA表达水平,以及Ⅲ型胶原蛋白(ColⅢ)、血管活性肠肽(VIP)蛋白表达水平和cAMP依赖性蛋白激酶(PKA)磷酸化水平。结果与正常组比较,放射组大鼠ROS、淀粉酶水平,细胞凋亡率、Bax表达水平和IL-6、TNF-αmRNA表达水平以及ColⅢ蛋白表达水平均显著升高,cAMP、SOD水平,Bcl-2表达水平和VIP蛋白表达水平及PKA磷酸化水平均显著降低(P<0.05);与放射组比较,红景天苷-L组和红景天苷-H组大鼠上述指标均显著改善(P<0.05),且红景天苷-H组改善更明显(P<0.05);抑制剂H-89显著逆转了红景天苷-H组大鼠上述指标的变化(P<0.05)。结论红景天苷可有效改善大鼠的腮腺放射性损伤,其机制可能与激活VIP-cAMP通路有关。 展开更多
关键词 红景天苷 放射性损伤 腮腺 vip-cAMP通路
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VIPS参数优化制备高性能膜蒸馏膜及其高矿化度矿井水处理应用
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作者 李真 刘淑琴 +2 位作者 李井峰 蒋斌斌 卞伟 《煤炭科学技术》 北大核心 2025年第10期282-293,共12页
膜蒸馏技术凭借运行压力低、可高效利用低品位热源等独特优势,在高矿化度矿井水零排放处理工艺体系中占据重要地位,是构建经济高效处理流程的关键技术单元之一,但高能量抗污染的膜蒸馏膜的欠缺阻碍了其迈向工业化应用。使用蒸汽诱导相分... 膜蒸馏技术凭借运行压力低、可高效利用低品位热源等独特优势,在高矿化度矿井水零排放处理工艺体系中占据重要地位,是构建经济高效处理流程的关键技术单元之一,但高能量抗污染的膜蒸馏膜的欠缺阻碍了其迈向工业化应用。使用蒸汽诱导相分离(VIPS)技术取代传统液致相分离技术制备疏水微孔聚偏氟乙烯(PVDF)膜,并将其应用在膜蒸馏高矿化度矿井水处理技术中。通过对VIPS过程温度、湿度、暴露时间等参数的协同调控,实现对膜结构与性能的优化。利用扫描电镜、孔隙率测试、孔径分析仪等表征手段,监测了不同参数条件对膜结构的影响,通过响应面法综合分析多因素之间的协同作用,使用高盐模拟水与宁东矿区真实高矿化度矿井水测试了优化VIPS膜在膜蒸馏过程中的实际性能表现。结果表明:温度升高会加速VIPS过程的相分离速度,减少膜表面结节结构的形成并帮助膜形成更大的孔径与孔隙率,但过高的温度会对孔隙率的提升起到抑制作用;湿度的增加有利于提升VIPS过程中非溶剂的入侵速率,帮助增大孔径与孔隙率,提升膜通量,但过高的湿度反而会使得孔隙封闭;暴露时间主要决定相分离的进程,暴露时间过短相分离不充分,暴露时间过长会使孔隙坍缩,适宜的暴露时间帮助形成均匀且高性能的膜。参数之间还存在不同程度的相互作用,温度与暴露时间的协同作用最为显著,其次是温度与湿度,而湿度与时间之间的作用较弱。最终使用温度40℃、湿度70%、暴露时间15 min为优化参数制备了VIPS膜,并且使用直接接触膜蒸馏装置评估了其处理性能。测试发现膜的平均通量分别达到14.75 L/(m^(2)·h)和14.03 L/(m^(2)·h),截留率均在99.9%以上,并且在测试期间始终保持稳定。测试前后膜表面电镜图片显示其并未出现明显的污染物附着情况,接触角测量数据测试前后也稳定在110°左右,说明膜具有较好的抗润湿和污染能力,展现出了良好的性能。 展开更多
关键词 高矿化度矿井水 膜蒸馏 蒸汽诱导相分离 PVDF膜
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基于VIP-MIC-SBS变量筛选的火电厂烟气流量软测量研究
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作者 邹祥波 熊凯 +6 位作者 陈公达 刘泽明 陈创庭 卢志民 卢伟业 陈小玄 姚顺春 《广东电力》 北大核心 2025年第8期1-11,共11页
碳排放连续在线监测法作为一种高效、可溯源的方法,在我国碳计量领域中逐渐应用。然而,由于烟囱管道的大直径、复杂烟气流场,以及流量计检修维护、粉尘堵塞导致的监测数据中断与异常,烟气流量的准确监测成为一大挑战。为此,提出一种融... 碳排放连续在线监测法作为一种高效、可溯源的方法,在我国碳计量领域中逐渐应用。然而,由于烟囱管道的大直径、复杂烟气流场,以及流量计检修维护、粉尘堵塞导致的监测数据中断与异常,烟气流量的准确监测成为一大挑战。为此,提出一种融合变量投影重要性分析(variable importance in projection,VIP)、最大信息系数(maximal information coefficient,MIC)及后向搜索(sequential backward selection,SBS)算法的联合筛选方法,结合支持向量机(support vector machine,SVM)构建烟气流量软测量模型。基于某F级燃气-蒸汽联合循环发电机组,通过VIP值评估辅助变量显著性,并结合MIC和SBS算法,进行变量冗余消除与优化选择,从而提升模型的预测精度和泛化能力。实验结果显示:SVM的表现优于长短时间记忆网络模型,与反向传播神经网络相比具有较好的泛化能力;当辅助变量数量为12时,模型性能最佳,测试集的均方根误差和平均绝对百分比误差均较低,验证了变量筛选方法的有效性;在稳态和非稳态工况下,模型预测值的平均绝对百分比误差小于0.7%,并有一定的滤波作用。 展开更多
关键词 烟气流量 软测量技术 变量投影重要性分析 最大信息系数 后向搜索 支持向量机
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Pilot Study of a School-Based Parenting Intervention:Prevention of Emotional and Behavioral Problems among Chinese Children 被引量:1
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作者 Jin Peng Jiabei He Na Li 《International Journal of Mental Health Promotion》 2025年第7期953-977,共25页
Background:Parenting exerts a profound influence on children’s mental health and behavioral development.Despite the high prevalence of children’s emotional and behavioral problems(CEBP)in China,evidence-based parent... Background:Parenting exerts a profound influence on children’s mental health and behavioral development.Despite the high prevalence of children’s emotional and behavioral problems(CEBP)in China,evidence-based parenting interventions remain scarcely investigated as preventive public health strategies.This pilot study evaluated a school-based intervention for preventing CEBP.Methods:We employed a quasi-experimental design with propensity score matching(PSM)to select 28 families(intervention:n=13;control:n=15)from two matched urban primary schools.Quantitative data from seven validated scales were analyzed using t-tests and ANCOVA.Qualitative insights were derived from 10 semi-structured interviews via thematic analysis.Results:Compared to the control group,the intervention group demonstrated significantly greater improvements in CEBP(p=0.020,Cohen’s d=0.92),parental adjustment(p=0.031,Cohen’s d=0.80),parenting confidence(p=0.003,Cohen’s d=1.04),and parentchild relationships(p=0.001,Cohen’s d=1.46).Non-significant effects were observed for parenting style,parental relationship,and parenting conflict(p>0.05).Qualitative analysis corroborated these findings and further identified contributing factors for non-significant outcomes,including challengeswithmeasurement adaptability and inconsistent co-parenting practices.Conclusions:This pilot study suggests that an authoritative parenting style may be effective and culturally adaptable in China.Positive parenting interventions appear to mitigate CEBP by reducing risk factors and enhancing protective factors.However,improving parental relationships and parenting conflict may require targeted strategies.Given the pilot nature of this PSM-matched study(n=28),the findings should be interpreted as exploratory and used primarily for intervention refinement. 展开更多
关键词 Parenting intervention CHILDREN SCHOOL-BASED China emotional and behavioral problems
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基于VIP设计法则的老年旅拍产品设计创新
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作者 高一可 洪歆慧 《设计》 2025年第3期64-68,共5页
探究ViP设计法则在老年旅拍场景中的应用价值,构建契合老年群体旅拍情境需求的产品设计策略框架,为老年旅拍产品的创新设计提供有力支撑。运用ViP设计法则的三层模型法,结合情境矩阵分析法,深入解构旅拍场景下老年群体在情境层、交互层... 探究ViP设计法则在老年旅拍场景中的应用价值,构建契合老年群体旅拍情境需求的产品设计策略框架,为老年旅拍产品的创新设计提供有力支撑。运用ViP设计法则的三层模型法,结合情境矩阵分析法,深入解构旅拍场景下老年群体在情境层、交互层、产品层的需求。通过大数据分析和小样本访谈,全面收集老年群体对现有旅拍产品与服务的看法、需求和期望,进行情境构建与产品定义。在ViP设计法则指导下,产出“忘年胶”老年旅拍相机创新型产品方案,在强化产品易用性、实用性、交互性、功能性的基础上,强化针对旅拍情境的衍生服务。研究成果为老年旅拍产品交互评估、机会洞察和设计创新提供了切实可行的参考依据。 展开更多
关键词 老年旅拍 vip设计法则 产品设计 用户体验 交互设计
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A unified M-tree self-correction solver for math word problems
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作者 Zhiyuan Ma Jiayu Liu Zhenya Huang 《中国科学技术大学学报》 北大核心 2025年第7期26-35,25,I0001,共12页
Automatically answer math word problems is a challenging task in artificial intelligence.Previous solvers constructed mathematical expressions in sequence or binary tree.However,these approaches may suffer from the fo... Automatically answer math word problems is a challenging task in artificial intelligence.Previous solvers constructed mathematical expressions in sequence or binary tree.However,these approaches may suffer from the following issues:Models relying on such structures exhibit fixed-order reasoning(e.g.,left-to-right),limiting flexibility and increasing error susceptibility;prior models rely on autoregressive reasoning in a single pass,accumulating minor errors(e.g.,incorrect math symbols)during generation,resulting in reduced accuracy.To address the above issues,we emulate the human“check and modify”process in reasoning and propose a unified M-tree self-correction solver(UTSCSolver)by iterative inference with self-correction mechanism.First,we use an iterative,non-autoregressive process for generating mathematical expressions,free from fixed generation orders to handle complex and diverse problems.Additionally,we design a self-correction mechanism based on alternating execution between a generator and a discriminator.This module iteratively detects and rectifies errors in generated expressions,leveraging previous iteration information for subsequent generation guidance.Experimental results show that our UTSC-Solver outperforms traditional models in accuracy on two popular datasets,while it improves the interpretability of mathematical reasoning. 展开更多
关键词 mathematical reasoning non-autoregressive generation math word problems
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