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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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Drifting Modulation Instability:Periodization of General Breathers,Asymmetric Sideband Modulation,and IST Spectral Portrait
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作者 Ming-Hao Ma Xiaotian Xu +1 位作者 Chong Liu Wen-Li Yang 《Chinese Physics Letters》 2026年第4期7-13,共7页
study drifting modulation instability(MI)that exhibits asymmetric discrete spectrum recurrences in the nonlinear stage within the framework of the focusing nonlinear Schr¨odinger equation.We demonstrate that such... study drifting modulation instability(MI)that exhibits asymmetric discrete spectrum recurrences in the nonlinear stage within the framework of the focusing nonlinear Schr¨odinger equation.We demonstrate that such drifting MI can arise either from the local periodization of general breathers or from numerical simulations starting with an initial modulation containing asymmetric sidebands. 展开更多
关键词 initial modulation containing asymmetric sidebands local periodization numerical simulations general breathers drifting modulation instability asymmetric sideband modulation asymmetric discrete spectrum recurrences spectral portrait
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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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A Study on the Intervention Effect of Whole- Process Blood Glucose Management for Patients with Diabetes Complicated with Cataract During the Postoperative Period
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作者 Ying Chen Siyu Zhou +3 位作者 Zhonglian Zhou Yangyang Wang Fen Liu Shuhu Feng 《Journal of Clinical and Nursing Research》 2026年第2期75-80,共6页
Objective:To explore the intervention effect of comprehensive perioperative blood glucose management on patients with diabetes complicated with cataract surgery.Method:A total of 68 patients in our hospital from July ... Objective:To explore the intervention effect of comprehensive perioperative blood glucose management on patients with diabetes complicated with cataract surgery.Method:A total of 68 patients in our hospital from July 2024 to July 2025 were selected and randomly divided into the experimental group and the control group,with 34 cases in each group.The control group received routine blood glucose management,while the experimental group,on this basis,implemented individualized intervention 3 days before the operation,real-time regulation during the operation,dynamic management 7 days after the operation,and self-management training.Result:The blood glucose control in the experimental group was more stable 7 days after the operation.The total incidence of complications(2.9%)was significantly lower than that in the control group(38.2%),and the average hospital stay(5.1±1.0 days)was shorter than that in the control group(7.3±1.4 days).One week after the operation,the proportions of uncorrected visual acuity and visual acuity≥0.6(67.6%)were both better than those of the control group(p<0.001).Conclusion:The whole-course management of perioperative blood glucose can enhance the stability of blood glucose control,reduce the risk of complications,shorten the length of hospital stay,promote visual recovery,and has high clinical promotion value. 展开更多
关键词 DIABETES CATARACT Perioperative period Full-course blood glucose management Intervention effect
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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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Information for Authors
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《Journal of Beijing Institute of Technology》 2026年第1期F0003-F0003,共1页
General Journal of Beijing Institute of Technology (JBIT)is a periodical publication on science and technology published by Beijing Institute of Technology under the sponsorship of the Ministry of Industry and Informa... General Journal of Beijing Institute of Technology (JBIT)is a periodical publication on science and technology published by Beijing Institute of Technology under the sponsorship of the Ministry of Industry and Information Technology of the People’s Republic of China.JBIT was inaugurated in 1992. 展开更多
关键词 Beijing Institute Technology science technology periodical publication Ministry Industry Information Technology China inauguration
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Imperial Power and Medicine:Ingot and Its Equipment Made by Qing Palace during Yongzheng Period
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作者 LI Haotian LIU Yanjun 《Chinese Medicine and Culture》 2026年第1期40-50,共11页
This study aims to explore the Qing court’s emphasis on traditional Chinese medicine(TCM)culture and technology,as well as the role of ingots as a carrier of imperial medical culture.By systematically sorting out the... This study aims to explore the Qing court’s emphasis on traditional Chinese medicine(TCM)culture and technology,as well as the role of ingots as a carrier of imperial medical culture.By systematically sorting out the types,quantities,and shapes of medicinal ingots recorded in Huo Ji Dang(活计档Archives of Imperial Workshops)during the 13-year Yongzheng reign,and by combining these records with existing ingot-related molds,physical specimens,and other collections in the Palace Museum,this research finds that:the Yongzheng Emperor incorporated ingots into the production list of the Imperial Workshop and established standardized preparation procedures,making them a technical practice for displaying imperial power;the fixed system of rewarding ingots during the Dragon Boat Festival turned ingots into a product of Manchu-Han cultural integration and formed a custom;the evolution of ingot equipment was dynamically related to military activities in the mid-Qing dynasty,confirming its function in court politics;and the integration of the preparation and packaging process of ingots into the power operation system,and transforming TCM-related knowledge and technology into means of exercising power,constructed a materialized path for imperial power to regulate the bureaucratic system and social order.The conclusion reveals the inherent logic of the Qing court:establishing authoritative identity through material culture. 展开更多
关键词 Yongzheng period Medicinal ingot Imperial power Traditional Chinese medicine
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Case analysis of diurnal stratospheric Rayleigh temperature and atmospheric fluctuations based on 589 nm lidar
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作者 ZhiFang Chen ZhaoAi Yan +5 位作者 Xiong Hu WenJie Guo ZunJie Wu HaiLong Sun ShangYong Guo YongQiang Cheng 《Earth and Planetary Physics》 2026年第2期251-258,共8页
Observational analysis of the Earth’s stratospheric temperature structure and its dynamical behavior is of great significance for atmospheric dynamics research.In this paper,we present stratospheric temperatures in t... Observational analysis of the Earth’s stratospheric temperature structure and its dynamical behavior is of great significance for atmospheric dynamics research.In this paper,we present stratospheric temperatures in the range of 30–50 km above the Yinchuan observation site,retrieved from diurnal continuous Rayleigh scattering signal observation data collected by a 589 nm lidar throughout a single day.We also present observational studies of atmospheric tides and gravity wave cases.The diurnal temperature background field and perturbation field were obtained from the lidar data using the linear fitting method;these results exhibit good consistency with the temperature perturbation field extracted from ERA5.An obvious quasi-monochromatic inertial gravity wave was detected by application of a two-dimensional Fourier transform to the nighttime observation data with complete height coverage,which revealed these characteristic gravity wave parameters:a vertical wavelength of 8.53 km,a period of 8.46 h,and a downward-propagating vertical phase velocity.A nonlinear least-squares harmonic fitting method was used to extract amplitudes and phases of atmospheric diurnal and semi-diurnal tides in the 30−34 km range,where the diurnal data were relatively complete.The amplitudes increased with height,ranging from 0.6 to 2.5 K(diurnal tide)and 0.3 to 1.9 K(semi-diurnal tide),respectively.The phases showed a decreasing trend with height,indicating that the vertical phase velocity of the tides propagates downward while the energy propagates upward.These results indicate that diurnal 589 nm lidar observations data can provide important reference values for understanding the temperature structure of the stratosphere and the dynamical characteristics of atmospheric gravity waves and tides. 展开更多
关键词 STRATOSPHERE atmospheric temperature quasi-monochromatic inertial gravity wave vertical wavelength period atmospheric tidal wave
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Structure-activity relationship in periodate activation by Fe-MOFs:Why MIL-101(Fe)outperforms other MIL-series in antibiotic degradation
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作者 Ning Liu Jingwen Xu +7 位作者 Yixuan Zhai Ziyi Zhang Yi Dang Yusong Cao Zhe Li Wenyuan Huang Xiaodong Zhang Liang Tang 《Green Energy & Environment》 2026年第2期578-590,共13页
Antibiotics are emerging pollutants that pose significant risks to environmental and human health.Periodate(PI)-based advanced oxidation processes have shown promise for their effective degradation.In this study,we sy... Antibiotics are emerging pollutants that pose significant risks to environmental and human health.Periodate(PI)-based advanced oxidation processes have shown promise for their effective degradation.In this study,we systematically investigate the structure-activity relationship of four representative Fe-based metal-organic frameworks(Fe-MOFs)-MIL-101(Fe),MIL-88B(Fe),MIL-88A(Fe),and MIL-53(Fe)-as PI activators for tetracycline(TC)degradation.Among them,MIL-101(Fe)exhibited the highest catalytic performance,owing to its unique Fe3O-OH nodes and mesoporous architecture.The MIL-101(Fe)/PI system achieved 93.3%TC degradation and 55.9%mineralization rate within 60 min.Mechanistic studies combining scavenger quenching,sulfoxide probe transformation,X-ray photoelectron spectroscopy,and X-ray absorption fine structure confirmed the generation of multiple reactive oxygen species,and high-valent Fe(IV)]O and O_(2)^(·-)played major roles in the tetracycline degradation process.Density functional theory calculations further revealed that MIL-101(Fe)and MIL-88B(Fe)effectively interact with PI to form Fe(Ⅲ)-superoxide(Fe(Ⅲ)-O-O^(·-)),a key intermediate in Fe(IV)]O generation.In contrast,the adsorption energy of MIL-53(Fe)and MIL-88A(Fe)was relatively weak,with fewer binding sites,resulting in poor performance.The synergy between Fe(Ⅲ)-O-O^(·-)formation and the pore accessibility of MIL-101(Fe)accounted for its superior catalytic efficiency.This work not only clarifies the structural factors governing PI activation in Fe-MOFs,but also proposes a mechanistically informed strategy for designing high-performance catalysts for antibiotic degradation. 展开更多
关键词 PERIODATE Advanced oxidation processes Fe-MOFs Antibiotic degradation Fe(Ⅲ)-Superoxide
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Periodic solutions and fixed-time synchronization of discontinuous time-varying delayed Cohen-Grossberg neural networks
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作者 ZHANG Yi-cheng KONG Fan-chao Rathinasamy Sakthivel 《Applied Mathematics(A Journal of Chinese Universities)》 2026年第1期140-160,共21页
In this paper,a class of discontinuous Cohen-Grossberg neural networks with timevarying delays is considered.Firstly,under the extended Filippov differential inclusions framework,the problem of periodic solutions of t... In this paper,a class of discontinuous Cohen-Grossberg neural networks with timevarying delays is considered.Firstly,under the extended Filippov differential inclusions framework,the problem of periodic solutions of the considered neural networks with more relaxed conditions imposed on the amplification functions is analyzed by using set-valued mapping and Kakutani's fixed point theorem,which has rarely been used to study such problem.Secondly,the fixed-time synchronization of the error system of the considered neural networks is also investigated by designing a novel control strategy,which can improve not only the previous ones with sign function greatly,but also can reduce the chattering phenomenon.Finally,two numerical examples are presented to further illustrate the validity of the obtained results. 展开更多
关键词 Cohen-Grossberg neural networks periodic solutions Kakutani's fixed point theorem differential inclusions theory fixed-time synchronization
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Next-generation craniomaxillofacial implants for reconstructive surgery: balancing biomechanics,biocompatibility,and bioactivity
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作者 Bozhi Hou Yuehua Li Raymond Chung Wen Wong 《International Journal of Oral Science》 2026年第1期1-17,共17页
Next-generation craniomaxillofacial implants(CMFIs) are redefining personalized bone reconstruction by balancing and optimizing biomechanics,biocompatibility,and bioactivity—the "3Bs".This review highlights... Next-generation craniomaxillofacial implants(CMFIs) are redefining personalized bone reconstruction by balancing and optimizing biomechanics,biocompatibility,and bioactivity—the "3Bs".This review highlights recent progress in implant design,material development,additive manufacturing,and preclinical evaluation.Emerging biomaterials,including bioresorbable polymers,magnesium alloys,and composites with bioactive ceramics,enable patient-specific solutions with improved safety and functionality.Triply periodic minimal surface(TPMS) architectures exemplify how structural design can enhance both mechanical performance and biological integration.Additive manufacturing technologies further allow the fabrication of geometrically complex,customized impla nts that meet individual anatomical and pathological needs.In parallel,multiscale evaluation techniques—from mechanical testing to in vitro and in vivo models—provide comprehensive insights into implant performance and safety.Looking ahead,the field is poised to benefit from several transformative trends:the development of smart and multifunctional biomaterials;Al-driven design frameworks that leverage patient-specific data and computational modeling;predictive additive manufacturing with real-time quality control;and advanced biological testing platforms for preclinical evaluation.Together,these advances form the foundation of a data-informed,translational pipeline from bench to bedside.Realizing the full potential of nextgene ration CMFIs will require close interdisciplina ry collaboration across mate rials science,computational engineering,and clinical medicine. 展开更多
关键词 bioresorbable polymersmagnesium alloysand BIOCOMPATIBILITY next generation craniomaxillofacial implants craniomaxillofacial implants cmfis periodic mini balancing optimizing BIOMECHANICS bioactive ceramicsenable
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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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Validation of time-space collocation method for simulating asymmetric unsteady flows in eccentric compressors
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作者 Haowei ZHOU Pengcheng DU Fangfei NING 《Chinese Journal of Aeronautics》 2026年第2期80-99,共20页
Circumferentially non-uniform tip clearances induced by rotor eccentricity significantly affect the overall performance of axial compressors,particularly the stability margin.Currently,Computational Fluid Dynamics(CFD... Circumferentially non-uniform tip clearances induced by rotor eccentricity significantly affect the overall performance of axial compressors,particularly the stability margin.Currently,Computational Fluid Dynamics(CFD)plays a crucial role in the aerodynamic analysis of eccentric compressors.However,conventional full-annulus Unsteady Reynolds-Averaged Navier-Stokes(URANS)simulations are prohibitively expensive for routine design and analysis purposes.To address this issue,the paper presents a novel Fourier-based method,called the Time-Space Collocation(TSC)method,for efficient simulations of eccentric compressors.This method coherently treats temporal and spatial harmonics,making it well-suited to tackle the rotor eccentricity problem,as the perturbation waves induced by eccentricity are time-periodic with respect to the rotor and space-periodic with respect to the stator.Three numerical cases,including NASA Rotor 67,original Stage 67,and Stage 67 with a reduced rotor-stator axial gap,were conducted to verify the effectiveness of the TSC method.The results indicate that,for the rotor eccentricity levels studied in this paper,the influence of weak rotor-stator interactions can be disregarded in the original Stage 67.In this situation,applying three harmonics can accurately capture both the performance variations and the non-uniformly distributed flowfields of eccentric compressors,while achieving a reduction in run time by two orders of magnitude compared to full-annulus URANS simulations.However,in Stage 67 with a reduced rotor-stator axial gap,the results that include rotor-stator interactions align much more closely with the URANS results.Nevertheless,the TSC simulations can still achieve speed-ups of several dozen times.Overall,the TSC method shows promising potential for application within the engineering community. 展开更多
关键词 Circumferentially nonuniform tip clearance Full-annulus unsteady simulation Rotor eccentricity Time-space collocation method Time-space periodic flow
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