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Solar insolation driven periodicities in southwest monsoon and its impact on NE Arabian Sea paleoceanography
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作者 Syed Azharuddin Pawan Govil +2 位作者 Arun Deo Singh Ravi Mishra Mayank Shekhar 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第6期2251-2263,共13页
In the northeastern(NE) Arabian Sea,the fluctuation in terrestrial and freshwater runoff directly depends on southwest monsoon(SWM) precipitation as well as the meltwater flux provided by Indus River.Therefore,analysi... In the northeastern(NE) Arabian Sea,the fluctuation in terrestrial and freshwater runoff directly depends on southwest monsoon(SWM) precipitation as well as the meltwater flux provided by Indus River.Therefore,analysis of multi-proxy spectral signatures was carried out to trace the high-resolution SWM periodicities and their influence on the productivity,regional sea level fluctuations and depositional processes in the NE Arabian Sea.The time series data of stable isotopes of oxygen(δ^18 O(G.ruber)).carbon(δ^13 C(G.ruber) and δ^13 C(org)) and nitrogen(δ^15 N).Total Organic Carbon(TOC),planktic-benthic foraminiferal ratio(P/B ratio) and>63 μm coarse fraction(CF) were used from two coastal sedimentary cores located offshore Saurashtra,NE Arabian Sea(Core SK-240/485 having 88 m water depth;Core GC/SK-240/496 having 174 m water depth).The REDFIT based spectral analysis recorded significant periodicities(>90% significance) in δ^18 0 time series centered at^1609,~667,~525,~296,~290 and^256 years.Further,the significant periodicities recorded in carbon isotopes time series(δ^13 C(G.ruber) and δ^13 C(org))centered at^681,~512,~471,~452,~438,~360,~292,~275,~269,~245 and^209 years.The significant periodicities in TOC include^471 and-322 years whereas δ^15 N time series recorded significant periodicity centered at-360 years.The significant periodicities in P/B ratio time series centered at^512,~388,~304,~250,~235,~217,~152,~139 and^135 years while CF recorded^268,~216,~209,~198,~188,~173 and^140 years significant periodicities.The observed periodicities in the multi-proxy record consist of similar cycles(within the radiocarbon dating error) which also natch with previously reported solar insolation influenced SWM and other global and regional cycles.Further,the stationarity of the data has been verified using wavelet analysis and shows similar periodicities as observed in REDFIT analysis.Thereafter,the depositional behaviour was studied using correlation analysis of the common periods of δ^18 0 time series of both the cores.The result suggests that the depositional behaviour was different for both the core sites during the early Holocene and became similar during the middle Holocene.The correlation analysis of Total Solar Index(TSI) with δ^18 O time series reveals a significant correlation with the core SK-240/485 whereas an insignificant correlation with the core GC/SK-240/496.These observations suggest that the solar insolation has been a leading factor responsible for the SWM trends during the Holocene which may have further influenced the productivity.regional sea level fluctuations and depositional conditions in the NE Arabian Sea.However,these trends are better preserved in shallow marine sediments as compared to the deeper marine sediments. 展开更多
关键词 SOUTHWEST MONSOON periodicities Arabian SEA Spectral analysis FORAMINIFERA
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Climatic periodicities recorded in lake sediment magnetic susceptibility data:Further evidence for solar forcing on Indian summer monsoon 被引量:3
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作者 Anish Kumar Warrier Kizhur Sandeep Rajasekharaiah Shankar 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第6期1349-1355,共7页
The Indian summer monsoon exhibits considerable spatio-temporal variability.It is therefore important to understand its dynamics and the inherent periodicities.In this study,we have performed spectral and wavelet anal... The Indian summer monsoon exhibits considerable spatio-temporal variability.It is therefore important to understand its dynamics and the inherent periodicities.In this study,we have performed spectral and wavelet analyses of magnetic susceptibility data for sediments from Thimmannanayakanakere(TK)-a small lake in southern India.The main objective of this investigation is to identify and explain the possible origin of the prominent periodicities present in the magnetic susceptibility data.Significant periodicities in the TK χ_(lf)data are centered at 906,232,147,128,96,61,54 and 44 years,which might have a solar origin.The wavelet power spectrum of the raw and detrended χ_(lf)data confirms the findings of spectral analysis and also provides temporal variations of the significant cyclicities during the past3700 cal.years B.P.Positive correlation is documented between sunspot activity and TK xif data;crossspectral analysis of the reconstructed sunspot data and TK xif data suggest that there is a strong coherence between the two datasets as significant periodicities are documented in both.There is a good match between the TK xif and the reconstructed total solar irradiance data for the past 1200 years.However,an out-of-phase relationship is documented at certain time-intervals,which may be attributed to uncertainties in the age-depth model.The results obtained from this study show that solar variations are the main controlling factor of the southwest monsoon and,like other archives from different regions in India,the TK lake sediments have also recorded these solar signatures. 展开更多
关键词 Spectral analysis PERIODICITY Paleorainfall Lake SEDIMENTS Magnetic SUSCEPTIBILITY Southern India
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Periodicities in the emplacement of large igneous provinces through the Phanerozoic:Relations to ocean chemistry and marine biodiversity evolution 被引量:9
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作者 Andreas Prokoph Hafida E1 Bilali Richard Ernst 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第3期263-276,共14页
Large igneous provinces (LIPs) are considered a relevant cause for mass extinctions of marine life throughout Earth's history. Their flood basalts and associated intrusions can cause significant release of SO4 and ... Large igneous provinces (LIPs) are considered a relevant cause for mass extinctions of marine life throughout Earth's history. Their flood basalts and associated intrusions can cause significant release of SO4 and CO2 and consequently, cause major environmental disruptions. Here, we reconstruct the long-term periodic pattern of LIP emplacement and its impact on ocean chemistry and biodiversity from δ34Ssulfate of the last 520 Ma under particular consideration of the preservation limits of LIP records. A combination of cross-wavelet and other time-series analysis methods has been applied to quantify a potential chain of linkage between LIP emplacement periodicity, geochemical changes and the Phanerozoic marine genera record. We suggest a mantle plume cyclicity represented by LIP volumes (V) of V= (350-770) × 103km3sin(27πt/ 170 Ma)+ (300-650)× 103 km3 sin(2πt/64.5 Ma + 2.3) for t= time in Ma. A shift from the 64.5 Ma to a weaker -28-35 Ma LIP cyclicity during the Jurassic contributes together with probably independent changes in the marine sulfur cycle to less ocean anoxia, and a general stabilization of ocean chemistry and increasing marine biodiversity throughout the last -135 Ma. The LIP cycle pattern is coherent with marine biodiversity fluctuations corresponding to a reduction of marine biodiversity of -120 genera/Ma at 600 x 103 km3 LIP eruption volume. The 62-65 Ma LIP cycle pattern as well as excursion in -34Ssulfate and marine genera reduction suggest a not-vet identified found LIP event at - 440-450 Ma. 展开更多
关键词 Large igneous provinces Wavelet transform Sulfur isotope Mantle plume Marine biodiversity Periodicity
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Seasonality Variability and Periodicities for Ultra-Deep Earthquakes Worldwide
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作者 Marilia Hagen Anibal Azevedo 《Open Journal of Earthquake Research》 2019年第1期1-18,共18页
Our last study found that deepest-depth earthquakes with larger magnitudes (M6 or above) showed seasonality, which is dependent on the area searched. The main results indicated strong evidence that the causes for the ... Our last study found that deepest-depth earthquakes with larger magnitudes (M6 or above) showed seasonality, which is dependent on the area searched. The main results indicated strong evidence that the causes for the delays in enhancements along the period investigated were due to the tectonics also, not only the season. Therefore, if the inquiry was about an area in Northern Hemisphere, the season in which the increases occurred is different than the season in the Southern Hemisphere. Also, higher latitudes in the Northern Hemisphere or around the Equator, displayed seasonality similarly where the tremors appear to increase during the Spring and Summer. This did not happen to the Southern Hemisphere where disturbances and anomalies occurred without showing much connection to the seasons in the analyzed period. However, some of the regions presented periodicities independent from the seasons. 展开更多
关键词 SEASONS SUBDUCTION Zones Earthquakes PERIODICITY South HEMISPHERE
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Computational Method for Extracting and Modeling Periodicities in Time Series
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作者 Eduardo González-Rodríguez Héctor Villalobos +1 位作者 Víctor Manuel Gomez-Munoz Alejandro Ramos-Rodríguez 《Open Journal of Statistics》 2015年第6期604-617,共14页
Periodicity is common in natural processes, however, extraction tools are typically difficult and cumbersome to use. Here we report a computational method developed in MATLAB through a function called Periods with the... Periodicity is common in natural processes, however, extraction tools are typically difficult and cumbersome to use. Here we report a computational method developed in MATLAB through a function called Periods with the aim to find the main harmonic components of time series data. This function is designed to obtain the period, amplitude and lag phase of the main harmonic components in a time series (Periods and lag phase components can be related to climate, social or economic events). It is based on methods of periodic regression with cyclic descent and includes statistical significance testing. The proposed method is very easy to use. Furthermore, it does not require full understanding of time series theory, nor require many inputs from the user. However, it is sufficiently flexible to undertake more complex tasks such as forecasting. Additionally, based on previous knowledge, specific periods can be included or excluded easily. The output results are organized into two groups. One contains the parameters of the adjusted model and their F statistics. The other consists of the harmonic parameters that best fit the original series according to their importance and the summarized statistics of the comparisons between successive models in the cyclic descent process. Periods is tested with both, simulated and actual sunspot and Multivariate ENSO Index data to show its performance and accuracy. 展开更多
关键词 Time Series Cyclic Descent Harmonic PERIODICITY Forecasting SUNSPOT Multivariate ENSO Index
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The Detection of Hidden Periodicities in EEG
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作者 YOU Rong-yi 《Chinese Journal of Biomedical Engineering(English Edition)》 2007年第4期179-183,共5页
A novel method for detecting the hidden periodicities in EEG is proposed. By using a width-varying window in the time domain, the structure function of EEG time series is defined. It is found that the minima of the st... A novel method for detecting the hidden periodicities in EEG is proposed. By using a width-varying window in the time domain, the structure function of EEG time series is defined. It is found that the minima of the structure function, within a finite window width, can be found regularly, which indicate that there are some certain periodicities associated with EEG time series. Based on the structure function, a further quadratic structure function of EEG time series is defined. By quadratic structure function, it can be seen that the periodicities of EEG become more obvious, moreover, the period of EEG can be determined accurately. These results will be meaningful for studying the neuron activity inside the human brain. 展开更多
关键词 electroencephalogram (EEG) PERIODICITY structure function
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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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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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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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Nonlinear coupling between 100 ka periodicity of the paleoclimate records in loess and periodicities of precession and semiprecession 被引量:2
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作者 余志伟 丁仲礼 《Science China Earth Sciences》 SCIE EI CAS 2003年第10期1077-1087,共11页
In this paper, we use the automatic orbital tuning method to establishthe time scales of Lingtai and Jingchuan loess-soil section, China, and Chashmanigar loess-soil section, Tadzhikistan, analyse the evolution of the... In this paper, we use the automatic orbital tuning method to establishthe time scales of Lingtai and Jingchuan loess-soil section, China, and Chashmanigar loess-soil section, Tadzhikistan, analyse the evolution of the ~100 ka cycles of the three paleoclimate records respectively and afterwards employ the auto-bicoherence method to detect the coupling between the ~100 ka periodicity and periodicities of obliquity, precession and semiprecession. The results show thatfrom 0.0 Ma to 0.8 Ma there exists a quadratic phase coupling between ~100 ka period and the period components of precession(16 ka) and semiprecession(about 13.8 ka, 12.4 ka, 11.1 ka), while from 1.6 Ma to 2.6 Ma, between 128 ka period and the period components of precession(19.3 ka and 16.8 ka) and semiprecession (about 10 ka). Evidence from the above calculation suggests that nonlinear interaction between precession and semiprecession waves may be the cause to produce ~100 ka cyclicity in loess records. 展开更多
关键词 PALEOCLIMATE periodicity precession semiprecession auto-bicoherence phase coupling.
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Periodicities in Cluster Algebras and Cluster Automorphism Groups
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作者 Siyang Liu Fang Li 《Algebra Colloquium》 SCIE CSCD 2021年第4期601-624,共24页
We study the relations between two groups related to cluster automorphism groups which are defined by Assem,Schiffler and Shamchenko.We establish the relation-ships among(strict)direct cluster automorphism groups and ... We study the relations between two groups related to cluster automorphism groups which are defined by Assem,Schiffler and Shamchenko.We establish the relation-ships among(strict)direct cluster automorphism groups and those groups consisting of periodicities of labeled seeds and exchange matrices,respectively,in the language of short exact sequences.As an application,we characterize automorphism-finite cluster algebras in the cases of bipartite seeds or finite mutation type.Finally,we study the relation between the group Aut(A)for a cluster algebra A and the group AutMn(S)for a mutation group Mn and a labeled mutation class S,and we give a negative answer via counter-examples to King and Pressland's problem. 展开更多
关键词 cluster algebra MUTATION cluster automorphism group PERIODICITY
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Selective CO_(2) conversion tuned by periodicities in Au_(8n+4)(TBBT)_(4n+8) nanoclusters
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作者 Dan Yang Wei Pei +10 位作者 Yuying Zhang Weigang Hu Xiao Cai Yongnan Sun Shuohao Li Xinglian Cheng Si Zhou Jijun Zhao Yan Zhu Weiping Ding Xu Liu 《Nano Research》 SCIE EI CAS CSCD 2021年第3期807-813,共7页
The structure-dependent catalytic behavior is one of the most important issues in catalysis science.However,it has not been fully understood how different types of atom-packing structures of heterogeneous catalysts pr... The structure-dependent catalytic behavior is one of the most important issues in catalysis science.However,it has not been fully understood how different types of atom-packing structures of heterogeneous catalysts precisely impact the reaction sites and pathways.Here we investigate a periodic series of Au_(8n+4)(TBBT)_(4n+8 )nanoclusters with layer-by-layer structural pattern to catalyze CO_(2) hydrogenation(where n=3–6 is the number of(001)layers;TBBT=4-tert-butyl-benzenethiolate).An encouraging evolution of CO_(2) conversion can be identified:The product selectivity from methanol,formic acid to ethanol can be switched by the structure-dependent deformation from the flattened,perfect,to elongated cuboids in Au_(8n+4)(TBBT)_(4n+8).Through a combined study of experiment and theory,we demonstrate that the variation in structural patterns of catalysts can exclusively tune their adsorption strength with reaction intermediates and further control the CO_(2) conversion toward the different products. 展开更多
关键词 Au8n+4(TBBT)4n+8 NANOCLUSTER periodicity catalysis CO_(2)conversion
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