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HOMOGENIZATION,SYMMETRY,AND PERIODIZATION IN DIFFUSIVE RANDOM MEDIA
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作者 Alen Alexanderian Muruhan Rathinam Rouben Rostamian 《Acta Mathematica Scientia》 SCIE CSCD 2012年第1期129-154,共26页
We present a systematic study of homogenization of diffusion in random me- dia with emphasis on tile-based random microstructures. We give detailed examples of several such media starting from their physical descripti... We present a systematic study of homogenization of diffusion in random me- dia with emphasis on tile-based random microstructures. We give detailed examples of several such media starting from their physical descriptions, then construct the associated probability spaces and verify their ergodicity. After a discussion of material symmetries of random media, we derive criteria for the isotropy of the homogenized limits in tile-based structures. ~rthermore, we study the periodization Mgorithm for the numerical approxi- mation of the homogenized diffusion tensor and study the algorithm's rate of convergence. For one dimensional tile-based media, we prove a central limit result, giving a concrete rate of convergence for periodization. We also provide numerical evidence for a similar central limit behavior in the case of two dimensional tile-based structures. 展开更多
关键词 HOMOGENIZATION periodization random media ergodic dynamical systems material symmetry ISOTROPY
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微穿孔板-三周期极小曲面复合吸声超材料设计与声学特性研究
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作者 张明康 刘文斌 +2 位作者 陈杰 王迪 王关皓 《航空制造技术》 北大核心 2026年第1期56-70,共15页
针对航空航天低频噪音问题,将微穿孔板(Microperforated plate,MPP)和三周期极小曲面(Triply periodic minimal surface,TPMS)进行复合设计获得MPP-TPMS夹芯结构,实现了对中低频噪声的高效吸声,同时保持了轻量化与紧凑性优势。选用TPMS... 针对航空航天低频噪音问题,将微穿孔板(Microperforated plate,MPP)和三周期极小曲面(Triply periodic minimal surface,TPMS)进行复合设计获得MPP-TPMS夹芯结构,实现了对中低频噪声的高效吸声,同时保持了轻量化与紧凑性优势。选用TPMS结构中的Primitive结构作为结构芯材,可通过设计穿孔板-腔体单元,形成亥姆霍兹共振器阵列。基于微穿孔板吸声理论和Johnson-Champoux-Allard等效流体理论,建立MPP-Primitive夹芯结构的吸声理论模型,探究局部共振效应和热粘滞耗散机制在声波衰减中的耦合作用。利用熔融沉积成型(Fused deposition modeling,FDM)技术制备样品,采用声阻抗管测试和有限元仿真,探究了微穿孔板、Primitive单元体尺寸、腔体厚度、MPP孔径对吸声特性的影响。结果表明,MPP结构与TPMS结构的组合设计,激活了结构中亥姆霍兹共振腔吸声机制,大幅提升吸声特性,吸声频带向低频区域移动,吸声峰值接近1;通过增大Primitive单元体尺寸,有效扩张共振腔体积,降低低频声阻抗,增强与低频声波声阻抗匹配,从而提升低频声波吸收效率;通过减小MPP孔径,使吸声峰峰值得到提升并向低频迁移;增加Primitive腔体厚度,延长声波传播路径,通过增强粘滞耗散与热传导效应将亥姆霍兹共振峰向低频迁移。这项工作为亚波长低频吸声MPP-TPMS复合吸声超材料制备提供了设计参考。 展开更多
关键词 三周期极小曲面(Triply periodic minimal surface TPMS) 微穿孔板(Microperforated plate MPP) 夹芯结构 熔融沉积成型(Fused deposition modeling FDM) 声学超材料
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Coupling of methanol and long chain alkanes on molecular sieves with CHA structures
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作者 YANG Chuang WANG Kangjun +1 位作者 LI Jinzhe LIU Zhongmin 《燃料化学学报(中英文)》 北大核心 2026年第2期64-75,共12页
The coupling reactions of methanol and long-chain alkanes(n-dodecane,n-tetradecane and n-hexadecane)over CHA-type molecular sieves were studied in a fixed bed reactor.Over SAPO-34 and SSZ-13,it was found that the indu... The coupling reactions of methanol and long-chain alkanes(n-dodecane,n-tetradecane and n-hexadecane)over CHA-type molecular sieves were studied in a fixed bed reactor.Over SAPO-34 and SSZ-13,it was found that the induction period of methanol conversion was shortened by the introduction of long-chain alkanes.However,the addition of long-chain alkanes had little influence on the product distribution.Polymethylbenzenes and the derivatives were the main retained species on spent SSZ-13 catalyst,while adamantanes were the main retained species on SAPO-34.This indicates that coking species formation was mainly related to the further transformation of long-chain alkane/methanol coupling products at acid sites of the molecular sieve.These findings provide valuable information of long chain alkanes conversion and methanol reaction behavior of induction period over small pore CHA molecular sieves. 展开更多
关键词 METHANOL long-chain alkane coupling transformation induction period molecular sieves
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Potential role of astrocyte on gamma-aminobutyric acid tone regulation during developmental period
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作者 Erva Ozkan Wuhyun Koh 《Neural Regeneration Research》 2026年第3期1118-1119,共2页
The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitte... The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitter,plays a crucial role in coordinating synapse formation,neuronal proliferation,and migration during this time. 展开更多
关键词 early developmental period developmental period brain cells neuronal proliferation synapse formation gamma aminobutyric acid ASTROCYTE GABA
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Inter-Individual Rapid Force Improvements after Mixed Session and Traditional Periodization in Aging Adults:A Randomized Trial
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作者 Bruno Monteiro Moura Ewertton de Souza Bezerra +2 位作者 Lucas B.R.Orssatto Antonio Renato Pereira Moro Fernando Diefenthaeler 《Journal of Science in Sport and Exercise》 2021年第2期125-137,共13页
Background Different periodization models have been widely used to improve maximum and rapid force in aging adults.However,it is unclear if some specific model can influence the remarkable heterogeneity of responsiven... Background Different periodization models have been widely used to improve maximum and rapid force in aging adults.However,it is unclear if some specific model can influence the remarkable heterogeneity of responsiveness to rapid torque improvements following resistance training.Aims Compare the effects of mixed session periodization(MSP)and traditional(TP)models on neuromuscular performance and individual responsiveness in aging adults.Methods Twenty-two aging men and women(64.6±5.2 years old;1.68±0.1 m;77.8±16.0 kg)completed the intervention period.They were assigned into MSP(n=11)or TP(n=11)resistance training for lower limbs.The outcome measures normalized dynamic leg press(5-RM:BM),absolute and normalized knee isometric peak torque(PT and PT:BM)and rate of torque development,and impulse were assessed at baseline and after three blocks of a 9-wk resistance training(3 sessions per week).Thigh leg lean mass was assessed by dual-energy x-ray absorptiometry at baseline and after the intervention.Results Similar increases were observed for 5-RM:BM(MSP:28.8%±13.5%and TP:26.4%±7.6%,P<0.001),PT(MSP:223.7±50.7 N·m and TP:189.9±58.6 N·m,P<0.001),but it was not observed for PT:BM(MSP:16.4%±16.5%and TP:4.7%±9.2%,P>0.05).Absolute and normalized RTD remained unchanged throughout intervention(P>0.05),but both groups improved impulse(MSP:22.1%±25.7%and TP:12.6%±45.2%,P<0.001).Only MSP responders(n=5)presented significant time effect for absolute RTD(P<0.05)and impulse(P<0.05).Conclusion Although both periodization protocols increased 5-RM:BM and PT,it was not interchangeable through improve-ments in RTD even adopting power training session.Furthermore,these results suggest a great inter-individual variability following different periodization models for aging people. 展开更多
关键词 Rate of torque development IMPULSE Strength training Muscular strength HYPERTROPHY periodization
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Research Progress on Malnutrition and Nutritional Intervention in Children with Leukemia During Chemotherapy
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作者 Xiangyan Cao Shuang Zhang Jialin Ye 《Proceedings of Anticancer Research》 2026年第1期61-68,共8页
This study systematically analyzed the primary causes of malnutrition in children with leukemia during chemotherapy,clarified the status of malnutrition and specific nutritional intervention measures,and comprehensive... This study systematically analyzed the primary causes of malnutrition in children with leukemia during chemotherapy,clarified the status of malnutrition and specific nutritional intervention measures,and comprehensively evaluated the research progress.The research indicates a shift from basic supportive care toward precision intervention strategies.Immunonutrition approaches,such as omega-3 fatty acid supplementation and probiotics for gut microbiota modulation,significantly mitigate chemotherapy-related side effects and enhance nutritional status.These targeted novel regimens demonstrate clear clinical advantages.The success of nutritional management depends on a multidisciplinary collaboration mechanism.The organic integration of innovative nutritional protocols with standard treatments from hematology,pediatrics,and nutrition departments significantly optimizes treatment outcomes and long-term quality of life for children with leukemia.This interdisciplinary synergy is reshaping contemporary medical models. 展开更多
关键词 Childhood leukemia Chemotherapy period MALNUTRITION Nutritional intervention
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The Application of Frailty Prediction Model for Middle-aged and Elderly Patients with Upper Gastrointestinal Bleeding in Peri-inpatient Nursing Intervention
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作者 Chaoxiang You Xiaoqin Ren +4 位作者 Fen Wu Ying Yang Jianrong Wang Cuixia Zhao Yuting He 《Journal of Clinical and Nursing Research》 2026年第1期161-166,共6页
Objective:To investigate the impact of targeted nursing interventions based on frailty prediction models on peri-hospitalization clinical outcomes in middle-aged and elderly patients with upper gastrointestinal bleedi... Objective:To investigate the impact of targeted nursing interventions based on frailty prediction models on peri-hospitalization clinical outcomes in middle-aged and elderly patients with upper gastrointestinal bleeding(UGIB).Methods:A prospective cohort study was conducted,and 126 middle-aged and elderly patients with UGIB admitted from August 2024 to August 2025 were selected as the study subjects.The patients were divided into the intervention group(63 cases)and the control group(63 cases)based on whether they received nursing intervention based on frailty prediction models.The control group received routine care,while the intervention group,on the basis of routine care,used the FRAIL scale combined with laboratory indicators(albumin,hemoglobin,etc.)to establish a predictive model to evaluate patients within 24 hours of admission,and implemented multi-dimensional targeted nursing intervention for pre-frailty or frailty patients screened out.The incidence of frailty,rebleeding rate,average length of stay,hospitalization cost,and nursing satisfaction during hospitalization were compared between the two groups.Results:The incidence of frailty during hospitalization in the intervention group was 11.1%(7 cases/63 cases),significantly lower than 31.7%(20 cases/63 cases)in the control group,and the difference was statistically significant(p<0.05).The rebleeding rate of 4.8%vs 12.7%,the average length of stay of(7.2±1.5)days vs(9.1±2.2)days,and the average hospitalization cost of(23,000±6,000)yuan vs(28,000±7,000)yuan in the intervention group were all lower than those in the control group(all p<0.05).The nursing satisfaction score of the intervention group(93.5±4.2)points was higher than that of the control group(86.3±5.8)points(p<0.05).Conclusion:The frailty prediction model applied to the peri-hospitalization care of middle-aged and elderly patients with UGIB can effectively identify frailty risk.Through early targeted intervention,the incidence of frailty and rebleeding rate can be reduced,the length of hospital stay can be shortened,medical expenses can be reduced,and nursing satisfaction can be improved,which has clinical promotion value. 展开更多
关键词 Upper gastrointestinal bleeding WEAKNESS Predictive models Elderly care Perioperative period
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THE DYNAMICAL BEHAVIOR OF AN ALMOST PERIODIC SVEIR WARNING MODEL IN A PATCHY ENVIRONMENT
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作者 Binguo WANG Xiaomei MA Yashi WANG 《Acta Mathematica Scientia》 2026年第1期427-458,共32页
The outbreak of infectious diseases is the result of a combination of various factors,including season,the movement of individuals,non-pharmaceutical interventions(NPIs)and the effectiveness and availability of vaccin... The outbreak of infectious diseases is the result of a combination of various factors,including season,the movement of individuals,non-pharmaceutical interventions(NPIs)and the effectiveness and availability of vaccines.Taking these key elements into consideration,an almost periodic SVEIR warning model in the patch environment is here proposed.First,in terms of reproduction numbers,our results imply that if the effective reproduction numbers are R_(e)<1,then the disease dies out;if R_(e)>1,then the disease spreads and leads to local outbreaks.Second,the relationships between R_(e)and C_(s1),C_(a1)(see Section 2)are given by numerical simulations.The numerical results show that even if all people are vaccinated,NPIs are still needed because of the potentially low efficacy of vaccines.Furthermore,the numerical results suggest that NPIs and the strengthening of the effective rate of vaccination are essential in order to achieve herd immunity.Theories involving this model effectively explain the transmission mechanism of most infectious diseases,and provide a valuable theoretical basis for analyzing new infectious diseases in the future.Moreover,this model is helpful for the prevention and control of infectious diseases and the formulation of public health safety policies. 展开更多
关键词 SVEIR model almost periodicity reproduction ratio skew-product semiflow threshold dynamics
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Research on the Impact of Evidence-Based Predictive Nursing on Elderly Cataract Patients During the Perioperative Period
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作者 Weijian Ma Lili Sun +1 位作者 Rong Zeng Yanling Liu 《Journal of Clinical and Nursing Research》 2026年第1期13-20,共8页
Objective:To explore the impact of evidence-based predictive nursing intervention on psychological stress and physiological indicator stability of elderly cataract patients during the perioperative period(1 day before... Objective:To explore the impact of evidence-based predictive nursing intervention on psychological stress and physiological indicator stability of elderly cataract patients during the perioperative period(1 day before surgery to 1 day after surgery),and to provide a basis for optimizing clinical nursing plans for elderly cataract surgery.Methods:A retrospective selection of 90 elderly patients(aged≥60 years)who underwent cataract surgery in the Ophthalmology Department of our hospital from August 2024 to December 2024 was conducted.They were divided into an observation group(n=45)and a control group(n=45)using a random number table method.The control group received routine nursing for cataract surgery,while the observation group implemented evidence-based predictive nursing intervention(including the establishment of a multidisciplinary evidence-based team,hierarchical psychological intervention,perioperative environment optimization,intraoperative personalized cooperation,and video-based health education).Psychological stress indicators[Self-Rating Anxiety Scale(SAS),Self-Rating Depression Scale(SDS),General Self-Efficacy Scale(GSES)]on the 1st day before surgery and 1st day after surgery,and fluctuations of physiological indicators[Heart Rate(HR),Systolic Blood Pressure(SBP),Diastolic Blood Pressure(DBP)]on the 1st day before surgery and during surgery were compared between the two groups.Results:Before intervention,there were no statistically significant differences in SAS,SDS,GSES scores,HR,SBP,or DBP between the two groups(p>0.05);after intervention,the SAS score(33.62±5.72)and SDS score(32.14±4.86)of the observation group on the 1st day after surgery were significantly lower than those of the control group[(41.05±5.56),(43.59±4.75)],and the GSES score(31.15±3.28)was significantly higher than that of the control group(24.84±3.52)(all p<0.05);during surgery,the fluctuations of HR(74.0±6.0)beats/min,SBP(127.0±15.8)mmHg,and DBP(75.0±5.9)mmHg in the observation group were significantly smaller than those in the control group(all p<0.05).Conclusion:Evidence-based predictive nursing intervention can effectively alleviate anxiety and depression in elderly cataract patients during the perioperative period,improve self-efficacy,stabilize intraoperative physiological status,and enhance surgical cooperation,which is worthy of clinical promotion. 展开更多
关键词 Evidence-based nursing Predictive nursing Elderly patients CATARACT Perioperative period Psychological stress Physiological stability SELF-EFFICACY
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Enhanced recovery after surgery-based recovery room nursing improves perioperative safety in gastrointestinal tumor surgery
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作者 Wan-Qi Zhong Su Wu +6 位作者 Ru-Xin Jiang Shao-Ru Chen Dan-Yang Li Jun Zhou Jiang-Xia Wu Ruo-Jing Zeng Hui Zhi 《World Journal of Gastrointestinal Oncology》 2026年第1期211-220,共10页
BACKGROUND Gastrointestinal(GI)tumors are among the most prevalent malignancies,and surgical intervention remains a primary treatment modality.However,the complexity of GI surgery often leads to prolonged recovery and... BACKGROUND Gastrointestinal(GI)tumors are among the most prevalent malignancies,and surgical intervention remains a primary treatment modality.However,the complexity of GI surgery often leads to prolonged recovery and high postoperative complication rates,which threaten patient safety and functional outcomes.Enhanced recovery after surgery(ERAS)principles have been shown to improve perioperative outcomes through evidence-based,multidisciplinary care pathways.Despite its widespread adoption,there is a paucity of research focusing specifically on optimizing ERAS-guided nursing processes in the post-anesthesia care unit(PACU)and evaluating its impact on perioperative safety in patients undergoing GI tumor surgery.This study aimed to investigate whether an ERASbased PACU nursing protocol could enhance recovery,reduce complications,and improve patient safety in this surgical population.AIM To explore the impact of optimizing the recovery room nursing process based on ERAS on the perioperative safety of patients with GI tumors.METHODS A total of 260 patients with GI tumors who underwent elective surgeries under general anesthesia in our hospital from August 2023 to August 2025 and were then observed in the recovery unit(PACU)were selected.They were randomly divided into the observation group(the PACU nursing process was optimized based on ERAS)and the control group(the conventional PACU nursing process was adopted)by the random number grouping method,with 130 cases in each group.The time of gastric tube removal,urinary catheter removal,defecation time,hospital stay,time of leaving the room after tube removal,retention time in the recovery room,occurrence of complications,satisfaction and readmission rate were compared between the two groups after entering the room.Compare the occurrence of adverse events in the PACU nursing process between the two groups.RESULTS The time of gastric tube removal,urinary catheter removal,defecation time,hospital stay,retention time in the recovery room,total incidence of complications and readmission rate in the observation group were significantly lower than those in the control group,and the satisfaction rate was higher than that in the control group(P<0.05).The occurrence of adverse events in the PACU nursing process in the observation group was lower than that in the control group(P<0.05).CONCLUSION Optimizing the PACU nursing process based on ERAS can effectively accelerate the recovery process of patients undergoing GI tumor surgery,reduce adverse events,improve nursing satisfaction,and at the same time,lower the incidence of adverse events in the PACU nursing process,providing a more refined management basis for clinical practice. 展开更多
关键词 Enhanced recovery after surgery Recovery room NURSING Gastrointestinal tumors Perioperative period
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Contents of linoleic acid,α-linolenic acid and their ratio in human milk,influence factors,and effects on infant health
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作者 Jiahui Yu Lili Zheng +7 位作者 Shengyuan Ye Xingwang Ye Shuangshuang Chen Zhiyuan Yan Zhengdong Liu Yuanyuan Yan Wei Wei Xingguo Wang 《Food Science and Human Wellness》 2026年第1期28-37,共10页
Both linoleic acid(18:2 n-6,LA)andα-linolenic acid(18:3 n-3,ALA)are essential fatty acids for infants.The contents of LA and ALA,and their ratio exhibited significant changes in human milk over the past 4 decades,whi... Both linoleic acid(18:2 n-6,LA)andα-linolenic acid(18:3 n-3,ALA)are essential fatty acids for infants.The contents of LA and ALA,and their ratio exhibited significant changes in human milk over the past 4 decades,which were not well summarized.Here,we summarized these values in 9898 human breast milk samples of 6664 mothers from 50 countries in 81 studies.A literature search was conducted using PubMed,Embase,and Web of Science between January 1980 and October 2023.The 95%confidence interval of LA/ALA ratio across lactation and gestation ranged from 14.24 to 31.26.The LA content was higher in China and Turkey(>20%)whereas the ALA content was below 1%in Africa.The LA/ALA ratio in countries along the Mediterranean coast exceeded 20 or even 30.LA and ALA contents increased significantly(P<0.01)while the ratio remained stable over the last 40 years.Multivariate meta-regression results showed that regions significantly(P<0.01)determined the LA,ALA,and LA/ALA ratio.Especially,maternal diet could definitely explain the variation while the effects of gestational age,lactation period was not significant.Clinical trials demonstrated that decreasing the LA/ALA ratio increased docosahexaenoic acid(22:6 n-3,DHA)status,reduced arachidonic acid(20:4 n-6,AA)contents,exerted no effect on the visual function of infants,and reached no consensus on growth.The current review aims to provide an overview on the LA and ALA contents and their ratio in human breast milk to raise concern in infant formula. 展开更多
关键词 Human milk Linoleic acid α-Linolenic acid Essential fatty acid Infant nutrition Clinical trial Lactation period Maternal diet
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Random State Approach to Quantum Computation of Electronic-Structure Properties
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作者 Yiran Bai Feng Xiong Xueheng Kuang 《Chinese Physics Letters》 2026年第1期89-104,共16页
Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and v... Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and viable quantum algorithms for simulating large-scale materials are still limited.We propose and implement random-state quantum algorithms to calculate electronic-structure properties of real materials.Using a random state circuit on a small number of qubits,we employ real-time evolution with first-order Trotter decomposition and Hadamard test to obtain electronic density of states,and we develop a modified quantum phase estimation algorithm to calculate real-space local density of states via direct quantum measurements.Furthermore,we validate these algorithms by numerically computing the density of states and spatial distributions of electronic states in graphene,twisted bilayer graphene quasicrystals,and fractal lattices,covering system sizes from hundreds to thousands of atoms.Our results manifest that the random-state quantum algorithms provide a general and qubit-efficient route to scalable simulations of electronic properties in large-scale periodic and aperiodic materials. 展开更多
关键词 periodic materials random state circuit random state quantum algorithms electronic structure properties density states aperiodic materials quantum algorithms quantum computation
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Clinical Observation of TCM Constitution Theory-Based Intervention in the Critical Window of AECOPD
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作者 Xiaoyan Wang Jianlong Ke +3 位作者 Yanyu Lv Hao Meng Yuke Wang Li Zhao 《Journal of Clinical and Nursing Research》 2026年第1期292-300,共9页
Objective:To observe the efficacy and safety of TCM syndrome differentiation-guided herbal intervention for patients with five constitutions during the high-risk window period of acute exacerbation of chronic obstruct... Objective:To observe the efficacy and safety of TCM syndrome differentiation-guided herbal intervention for patients with five constitutions during the high-risk window period of acute exacerbation of chronic obstructive pulmonary disease(AECOPD)based on TCM constitution theory.Methods:A total of 300 AECOPD patients in the high-risk window period(54-66 cases for each constitution)were randomly divided into two groups(150 cases each).The control group received fluticasone furoate/umeclidinium/vilanterol inhalation therapy,while the experimental group was additionally given constitution-specific TCM decoctions(e.g.,Erchen Decoction combined with Sanzi Yangqin Decoction for Phlegm-Dampness constitution).The treatment course was 8 weeks with a 6-month follow-up.CAT score,TCM syndrome score,pulmonary function,6-minute walking distance(6MWD),and levels of CRP and IL-6 were observed.Recurrence and safety indicators were recorded.Results:After treatment,all indicators improved significantly in both groups(p<0.05),with the experimental group showing superior improvements in CAT score,TCM syndrome score,FEV1,6MWD,and inflammatory indicators(p<0.01).The recurrence rate was lower in the experimental group during follow-up(p<0.05).No severe adverse reactions or abnormalities in liver/kidney function were observed in either group.Conclusion:TCM syndrome differentiation treatment guided by constitution theory can improve symptoms,quality of life,and pulmonary function,reduce inflammatory levels and recurrence rate in AECOPD patients during the high-risk window period,with good safety. 展开更多
关键词 TCM constitution theory Acute exacerbation of chronic obstructive pulmonary disease(AECOPD) Risk window period
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Breaking the scalability and monolithic shaping barriers with a solid-state hot-pressing strategy for COFs
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作者 Xia Li Zhenjie Zhang 《Science China Materials》 2026年第3期1808-1809,共2页
Covalent organic frameworks(COFs)are an emerging class of porous crystalline materials formed by the precise assembly of organic molecular building blocks into extended periodic structures via strong covalent bonds.Th... Covalent organic frameworks(COFs)are an emerging class of porous crystalline materials formed by the precise assembly of organic molecular building blocks into extended periodic structures via strong covalent bonds.They feature well-defined pore structure,high specific surface area,and tunable physicochemical properties,endowing them with broad application prospects in gas storage,molecular separation. 展开更多
关键词 strong covalent bondsthey gas storagemolecular separation covalent organic frameworks porous crystalline materials solid state hot pressing assembly organic molecular building blocks extended periodic structures covalent organic frameworks cofs SCALABILITY
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番红砗磲生物钟基因Cryptochrome和Period克隆鉴定及光照相关性分析
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作者 杨文红 南祎晗 +4 位作者 李萌 刘春胜 杨毅 於锋 顾志峰 《渔业科学进展》 北大核心 2025年第4期153-167,共15页
生物钟是生物体适应地球周期性昼夜变化而演化出体内自持的计时机制,Cryptochrome和Period是生物钟的2个核心基因,其通过形成PER/CRY异二聚体调控生物体节律。本研究应用分子生物学和生物信息学技术对番红砗磲(Tridacna crocea)生物钟基... 生物钟是生物体适应地球周期性昼夜变化而演化出体内自持的计时机制,Cryptochrome和Period是生物钟的2个核心基因,其通过形成PER/CRY异二聚体调控生物体节律。本研究应用分子生物学和生物信息学技术对番红砗磲(Tridacna crocea)生物钟基因Cryptochrome和Period的编码区进行了克隆和特征分析,继而开展了其组织特异性和不同光照周期下的表达节律性研究。结果显示,Cryptochrome编码区碱基序列长1641 bp,编码546个氨基酸,理论等电点为6.08,分子量为62.98 kDa;Period编码区碱基序列长4386 bp,编码1461个氨基酸,理论等电点为6.14,分子量为164.99 kDa;Hdock互作模式研究结果显示,2个蛋白可形成异二聚体,结合能为–279.88 kcal/mol。组织表达分析显示,Cryptochrome和Period在7个组织中均有表达,其中,外外套膜、内外套膜、鳃和闭壳肌相对表达量较高(Cryptochrome在心脏中亦有较高表达量)。Cryptochrome和Period基因在外外套膜、内外套膜、鳃和闭壳肌中均昼夜变化,并呈现振荡表达的规律。在内、外外套膜中,Cryptochrome和Period基因分别在光照后1 h和光照前2 h表达量达到最高,且均随光照周期的推移(光照时间07:00~19:00推迟至09:00~21:00)而推移;在鳃组织中,正常光周期处理的Cryptochrome和Period基因均在光照前1 h表达量达到最高,当光照延迟2 h后,2个基因的最高表达时间推至光照后1 h;与之相反,闭壳肌中Cryptochrome和Period基因在08:00左右表达量最高,且未随光照延迟而发生变化。综上,本研究首次克隆获得番红砗磲2个关键生物钟基因Cryptochrome和Period,初步验证了这2个基因在主要组织表达的昼夜节律性,结果对揭示番红砗磲行为、生理节律和光照适应机制具有重要意义。 展开更多
关键词 番红砗磲 Cryptochrome和Period 昼夜节律 表达规律
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Circadian disruption by simulated shift work aggravates periodontitis via orchestrating BMAL1 and GSDMD-mediated pyroptosis 被引量:2
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作者 Yazheng Wang Rui Li +6 位作者 Qingyuan Ye Dongdong Fei Xige Zhang Junling Huang Tingjie Liu Jinjin Wang Qintao Wang 《International Journal of Oral Science》 2025年第1期122-132,共11页
Approximately 20%to 30%of the global workforce is engaged in shift work.As a significant cause of circadian disruption,shift work is closely associated with an increased risk for periodontitis.Nevertheless,how shift w... Approximately 20%to 30%of the global workforce is engaged in shift work.As a significant cause of circadian disruption,shift work is closely associated with an increased risk for periodontitis.Nevertheless,how shift work-related circadian disruption functions in periodontitis remains unknown.Herein,we employed a simulated shift work model constructed by controlling the environmental light-dark cycles and revealed that shift work-related circadian disruption exacerbated the progression of experimental periodontitis.RNA sequencing and in vitro experiments indicated that downregulation of the core circadian protein brain and muscle ARNT-like protein 1(BMAL1)and activation of the Gasdermin D(GSDMD)-mediated pyroptosis were involved in the pathogenesis of that.Mechanically,BMAL1 regulated GSDMD-mediated pyroptosis by suppressing NOD-like receptor protein 3(NLRP3)inflammasome signaling through modulating nuclear receptor subfamily 1 group D member 1(NR1D1),and inhibiting Gsdmd transcription via directly binding to the E-box elements in its promoter.GSDMD-mediated pyroptosis accelerated periodontitis progression,whereas downregulated BMAL1 under circadian disruption further aggravated periodontal destruction by increasing GSDMD activity.And restoring the level of BMAL1 by circadian recovery and SR8278 injection alleviated simulated shift work-exacerbated periodontitis via lessening GSDMD-mediated pyroptosis.These findings provide new evidence and potential interventional targets for circadian disruption-accelerated periodontitis. 展开更多
关键词 BMAL1 NLRP3 PERIOD
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An Improved Repetitive-Control System Using a Complex-Coefficient Filter 被引量:1
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作者 Qicheng Mei Jinhua She +1 位作者 Fei Long Yanjun Shen 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期282-284,共3页
Dear Editor,This letter presents an improved repetitive controller(IRC) that uses a complex-coefficient filter to enhance the tracking performance of a system for periodic signals. Compared with the low-pass filter us... Dear Editor,This letter presents an improved repetitive controller(IRC) that uses a complex-coefficient filter to enhance the tracking performance of a system for periodic signals. Compared with the low-pass filter used in the conventional repetitive controller(CRC), the complex-coefficient filter causes less change in the phase and amplitude of a signal at the frequencies of the periodic signal, especially at the fundamental frequency, when the two filters have the same cutofffrequency. 展开更多
关键词 improved repetitive controller irc periodic signals repetitive control system complex coefficient filter tracking performance conventional repetitive controller crc periodic signal enhance tracking performance
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Research on the rapid diagnosis method for hunting of high-speed trains 被引量:1
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作者 Wanru Xie Yixin Zhao +3 位作者 Gang Zhao Fei Yang Zilong Wei Jinzhao Liu 《Railway Sciences》 2025年第1期1-21,共21页
Purpose–High-speed turnouts are more complex in structure and thus may cause abnormal vibration of highspeed train car body,affecting driving safety and passenger riding experience.Therefore,it is necessary to analyz... Purpose–High-speed turnouts are more complex in structure and thus may cause abnormal vibration of highspeed train car body,affecting driving safety and passenger riding experience.Therefore,it is necessary to analyze the data characteristics of continuous hunting of high-speed trains passing through turnouts and propose a diagnostic method for engineering applications.Design/methodology/approach–First,Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)is performed to determine the first characteristic component of the car body’s lateral acceleration.Then,the Short-Time Fourier Transform(STFT)is performed to calculate the marginal spectra.Finally,the presence of a continuous hunting problem is determined based on the results of the comparison calculations and diagnostic thresholds.To improve computational efficiency,permutation entropy(PE)is used as a fast indicator to identify turnouts with potential problems.Findings–Under continuous hunting conditions,the PE is less than 0.90;the ratio of the maximum peak value of the signal component to the original signal peak value exceeded 0.7,and there is an energy band in the STFT time-frequency map,which corresponds to a frequency distribution range of 1–2 Hz.Originality/value–The research results have revealed the lateral vibration characteristics of the high-speed train’s car body during continuous hunting when passing through turnouts.On this basis,an effective diagnostic method has been proposed.With a focus on practical engineering applications,a rapid screening index for identifying potential issues has been proposed,significantly enhancing the efficiency of diagnostic processes. 展开更多
关键词 High-speed railway Periodic hunting Rapid diagnosis CEEMDAN STFT Permutation entropy
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Enhancing angiogenesis and osseointegration through a double gyroid Ti6Al4V scaffold with triply periodic minimal surface 被引量:1
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作者 Hao Liu Hao Chen +9 位作者 Bin Sun Danyang Fan Aobo Zhang Hanqiang Liu Hexiang Wei Wenbo Yang Yongyue Li Peng Xia Qing Han Jincheng Wang 《Bio-Design and Manufacturing》 2025年第1期36-54,I0013-I0017,共24页
The pore structure of porous scaffolds plays a crucial role in bone repair.The prevalent bone implant structure in clinical practice is the traditional cubic structure.However,the traditional cubic structure exhibits ... The pore structure of porous scaffolds plays a crucial role in bone repair.The prevalent bone implant structure in clinical practice is the traditional cubic structure.However,the traditional cubic structure exhibits sharp edges and junctions that are not conducive to cell adhesion or growth.In this study,a double gyroid(DG)Ti6Al4V scaffold based on a triply periodic minimal surface(TPMS)structure was devised,and the osseointegration performance of DG structural scaffolds with varying porosities was investigated.Compression tests revealed that the elastic modulus and compressive strength of DG structural scaffolds were sufficient for orthopedic implants.In vitro cellular experiments demonstrated that the DG structure significantly enhanced cell proliferation,vascularization,and osteogenic differentiation compared to the cubic structure.The DG structure with 55%porosity exhibited the most favorable outcomes.In vivo experiments in rabbits further demonstrated that DG scaffolds could promote neovascularization and bone regeneration and maturation;those with 55%porosity performed best.Comparing the surface area,specific surface area per unit volume,and internal flow distribution characteristics of gyroid and DG structure scaffolds,the latter are more conducive to cell adhesion and growth within scaffolds.This study underscored the potential of DG scaffolds based on the TPMS structure in optimizing the pore structure design of titanium scaffolds,inducing angiogenesis,and advancing the clinical application of titanium scaffolds for repairing bone defects. 展开更多
关键词 Double gyroid Triply periodic minimal surface OSSEOINTEGRATION ANGIOGENESIS
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Efficacyand safety of exercise rehabilitation in the vulnerable phase in patients with acute decompensated heart failure:A systematic review and meta-analysis 被引量:1
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作者 Lihua Zhao Jing Ye +2 位作者 Zhuo Zhao Lei Yang Yimei Zheng 《International Journal of Nursing Sciences》 2025年第4期408-414,I0006,I0007,共9页
Objectives:This study aimed to assess the impact of exercise rehabilitation during the vulnerable period on cardiac recovery(CR)outcomes in patients with acute decompensated heart failure(ADHF).Methods:Multiple databa... Objectives:This study aimed to assess the impact of exercise rehabilitation during the vulnerable period on cardiac recovery(CR)outcomes in patients with acute decompensated heart failure(ADHF).Methods:Multiple databases including PubMed,Web of Science,Embase,the Cochrane Library,CINAHL,China National Knowledge Infrastructure(CNKI),Chinese Science and Technology Periodical Database(VIP),Wanfang database,SinoMed,ClinicalTrials.gov,and American Heart Association(AHA)and European Society of Cardiology(ESC)were searched for RCTs on exercise rehabilitation in ADHF patients’vulnerable period from inception to April 2,2025.The risk of bias was assessed with Cochrane Risk of Bias 2.0,and data were analyzed in RevMan 5.3.Results:A total of seven RCTs involving 946 patients were included.The results demonstrated that exercise rehabilitation training during the vulnerable period in patients with ADHF significantly increased the 6-min walk test distance(6-MWTD)(SMD=0.37;95%CI:0.09,0.65;P=0.01),short physical performance battery(SPPB)score(MD=1.26;95%CI:0.82,1.70;P<0.001)and peak oxygen consumption(VO2peak)(SMD=1.43;95%CI:0.53,2.34;P=0.002),improved quality of life(QoL)(SMD=0.85;95%CI:0.07,1.64,P=0.03),reduced depression score(MD=-0.73;95%CI:1.27,-0.18;P=0.009),frailty(MD=-0.22;95%CI:-0.48,0.05;P=0.11),and decreased 6-month all-cause readmission(OR=0.67;95%CI:0.49,0.91;P=0.01).However,no statistically significantdifferences were observed between the two groups in left ventricular ejection fraction(LVEF)(MD=0.96;95%CI:-1.84,3.77;P=0.50),6-month heart failure(HF)-related readmission(OR=1.01;95%CI:0.66,1.53;P=0.98),and all-cause mortality(OR=0.63;95%CI:0.18,2.24;P=0.47).There were no adverse events reported.Conclusions:Exercise rehabilitation during the vulnerable phase improves exercise tolerance,QoL,and depressive symptoms while reducing 6-month all-cause readmissions in ADHF patients,with no reported adverse events.Although trends toward improved LVEF,HF-related readmissions,and all-cause mortality were observed.Large-scale,high-quality studies are warranted to explore individualized responses and long-term outcomes. 展开更多
关键词 Acute decompensated heart failure Exercise rehabilitation Evidence-based nursing META-ANALYSIS Vulnerable period
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