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Sustained release of vascular endothelial growth factor A and basic fibroblast growth factor from nanofiber membranes reduces oxygen/glucose deprivation-induced injury to neurovascular units 被引量:4
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作者 Yifang Wu Jun Sun +2 位作者 Qi Lin Dapeng Wang Jian Hai 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期887-894,共8页
Upregulation of vascular endothelial growth factor A/basic fibroblast growth factor(VEGFA/b FGF)expression in the penumbra of cerebral ischemia can increase vascular volume,reduce lesion volume,and enhance neural cell... Upregulation of vascular endothelial growth factor A/basic fibroblast growth factor(VEGFA/b FGF)expression in the penumbra of cerebral ischemia can increase vascular volume,reduce lesion volume,and enhance neural cell proliferation and differentiation,thereby exerting neuroprotective effects.However,the beneficial effects of endogenous VEGFA/b FGF are limited as their expression is only transiently increased.In this study,we generated multilayered nanofiber membranes loaded with VEGFA/b FGF using layer-by-layer self-assembly and electrospinning techniques.We found that a membrane containing 10 layers had an ideal ultrastructure and could efficiently and stably release growth factors for more than 1 month.This 10-layered nanofiber membrane promoted brain microvascular endothelial cell tube formation and proliferation,inhibited neuronal apoptosis,upregulated the expression of tight junction proteins,and improved the viability of various cellular components of neurovascular units under conditions of oxygen/glucose deprivation.Furthermore,this nanofiber membrane decreased the expression of Janus kinase-2/signal transducer and activator of transcription-3(JAK2/STAT3),Bax/Bcl-2,and cleaved caspase-3.Therefore,this nanofiber membrane exhibits a neuroprotective effect on oxygen/glucose-deprived neurovascular units by inhibiting the JAK2/STAT3 pathway. 展开更多
关键词 brain ischemia brain microvascular endothelial cell nanofiber membrane neurovascular unit
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Risk Factors for Mortality in Acute Kidney Injury in Intensive Care Units in Togo
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作者 Eyram Makafui Yoan Yawo Amekoudi Kossi Akomola Sabi +3 位作者 Marcel David Keoula Badomta Dolaama Sarakawabalo Assenouwe Tabana Mouzou 《Open Journal of Nephrology》 2024年第1期37-47,共11页
Context: Acute kidney injury (AKI) in intensive care unit (ICU) is common and associated with very high mortality. In Togo, a tropical country with limited resources and only one nephrology department in the north, ac... Context: Acute kidney injury (AKI) in intensive care unit (ICU) is common and associated with very high mortality. In Togo, a tropical country with limited resources and only one nephrology department in the north, acute kidney injury seems to be a real tragedy with high mortality. Aims: to determine risk factors for mortality in acute kidney injury in the intensive care units. Methods and Material: We made a multicentric cross sectional study during 6 months in the four referral centers in northern Togo. Univariate and multivariate logistic regression was used to identify factors associated with mortality. Data were analyzed using RStudio 2023.04.1. Results: A total of 12.6% of patients admitted to intensive care had presented with AKI. The mean age was 49.6 ± 17.9. The sex ratio (M/F) was 2.1. Community-acquired AKI was in the majority (67.7%). Oligo anuria was the most frequent functional sign (38.4%). In our series, 81.6% of patients were in KDIGO stages 2 to 3. AKI was organic in 56.2% of cases. Mortality was 44.3%. In multivariate analysis, the main factors predictive of death were: respiratory distress (OR = 2.36;p Conclusions: Acute kidney injury in intensive care is common in northern Togo, and mortality is high. Identification of associated factors should help anticipate prognosis. 展开更多
关键词 AKI Intensive Care Unit DIALYSIS EPIDEMIOLOGY TOGO
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Nurse Stress Associated with Delirium Care in Intensive Care Units: A Cross-Sectional Study
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作者 Tingting Xiao 《Open Journal of Nursing》 2024年第11期569-578,共10页
Background and Objectives: Delirium is highly prevalent in Intensive Care Units (ICUs). While prior studies have identified hyperactive and hyperalert behaviors as major stressors for nurses caring for delirious patie... Background and Objectives: Delirium is highly prevalent in Intensive Care Units (ICUs). While prior studies have identified hyperactive and hyperalert behaviors as major stressors for nurses caring for delirious patients, limited research exists on ICU nurses’ stress specifically related to delirium care. This study aims to investigate the stress experienced by ICU nurses in China when managing patients with delirium. Methods: This cross-sectional survey was conducted in China from January to February 2023. A total of 243 ICU nurses participated by completing an online survey that included the Personal Information Questionnaire and the Strain of Caring for Delirium Index (SCDI). Although 260 responses were initially collected, 29 invalid questionnaires were excluded, resulting in a final sample size of 243 valid responses. The SCDI scale demonstrated reliable internal consistency, with Cronbach’s α coefficients of 0.744, 0.812, 0.778, and 0.920 across its four subscales. Results: The survey results indicated that hypoactive delirium behaviors were perceived as the most significant stressors when caring for delirious patients. Among the behaviors, “noisy/yelling” was identified as the most challenging, whereas “pulling at tubes, dressings” was rated as the least challenging. No significant associations were found between demographic factors and stress levels. Conclusion: This study sheds light on the stress levels ICU nurses experience when caring for delirious patients, particularly in relation to hypoactive behaviors. Based on these findings, it is recommended that nurse managers implement stress management strategies and provide targeted delirium-related care training to better support ICU nurses and enhance the quality of delirium care. 展开更多
关键词 DELIRIUM STRESS Intensive Care units NURSE
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A conceptual analysis of facilitation to improve clinical outcomes in critical care units
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作者 Mpho G.Chipu Charlené Downing 《International Journal of Nursing Sciences》 CSCD 2024年第5期595-603,共9页
Objectives:Effective facilitation is crucial to improve critical care outcomes in life-threatening conditions through improved teamwork,caring,decision-making,and problem-solving.The meaning of facilitation remains un... Objectives:Effective facilitation is crucial to improve critical care outcomes in life-threatening conditions through improved teamwork,caring,decision-making,and problem-solving.The meaning of facilitation remains unprecise in a critical care context despite its frequent usage in nursing education and clinical practice.This study aimed to report a thorough concept analysis to clarify the meaning of facilitation in the critical care context by formulating attributes,antecedents,and consequences and providing model cases related to facilitation.Methods:This analysis was performed by searching online sources published from 1999 to 2023.EBSCOhost,CINAHL,PubMed,and Google Scholar databases were searched using online search engines.The analysis also included the manual search of books,thesaurus and dictionaries that showed relevance to facilitation.Walker and Avant’s eight-step approach was applied to explore and analyze the meaning of facilitation in critical care units.Results:A total of 68 articles were included in the analysis of this study.Eleven attributes,six antecedents,and seven consequences related to facilitation were formulated.The attributes included dynamic,interactive processes,creating a positive environment,mobilizing resources,assistance,studentcentered,shared goals,collaboration,engagement,participation,and feedback.Antecedents were facilitator qualities,motivation,a positive learning environment,student-facilitator relationship,time availability,and specified learning outcomes.The consequences of facilitation were identified as follows:change,professional development,competency,quality development,increased job satisfaction,staff retention,and self-confidence.Conclusions:The findings from the analysis indicated that effective facilitation results in nurses and critical care staff developing competency,caring,critical thinking,and independence.Therefore,clinical outcomes in critical care environments are improved through teamwork,decision-making,and problemsolving in life-threatening situations. 展开更多
关键词 Concept analysis Nurses Critical care units FACILITATION FACILITATORS
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One memristor–one electrolyte-gated transistor-based high energy-efficient dropout neuronal units
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作者 李亚霖 时凯璐 +4 位作者 朱一新 方晓 崔航源 万青 万昌锦 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期569-573,共5页
Artificial neural networks(ANN) have been extensively researched due to their significant energy-saving benefits.Hardware implementations of ANN with dropout function would be able to avoid the overfitting problem. Th... Artificial neural networks(ANN) have been extensively researched due to their significant energy-saving benefits.Hardware implementations of ANN with dropout function would be able to avoid the overfitting problem. This letter reports a dropout neuronal unit(1R1T-DNU) based on one memristor–one electrolyte-gated transistor with an ultralow energy consumption of 25 p J/spike. A dropout neural network is constructed based on such a device and has been verified by MNIST dataset, demonstrating high recognition accuracies(> 90%) within a large range of dropout probabilities up to40%. The running time can be reduced by increasing dropout probability without a significant loss in accuracy. Our results indicate the great potential of introducing such 1R1T-DNUs in full-hardware neural networks to enhance energy efficiency and to solve the overfitting problem. 展开更多
关键词 dropout neuronal unit synaptic transistors MEMRISTOR artificial neural network
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Hounsfield units in assessing bone mineral density in ankylosing spondylitis patients with cervical fracture-dislocation
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作者 Zhong-Ya Gao Wei-Lin Peng +1 位作者 Yang Li Xu-Hua Lu 《World Journal of Clinical Cases》 SCIE 2024年第23期5329-5337,共9页
BACKGROUND Cervical spine fracture-dislocations in patients with ankylosing spondylitis(AS)are mostly unstable and require surgery.However,osteoporosis,one of the comorbidities for AS,could lead to detrimental prognos... BACKGROUND Cervical spine fracture-dislocations in patients with ankylosing spondylitis(AS)are mostly unstable and require surgery.However,osteoporosis,one of the comorbidities for AS,could lead to detrimental prognoses.There are few accurate assessments of bone mineral density in AS patients.AIM To analyze Hounsfield units(HUs)for assessing bone mineral density in AS patients with cervical fracture-dislocation.METHODS The HUs from C2 to C7 of 51 patients obtained from computed tomography(CT)scans and three-dimensional reconstruction of the cervical spine were independently assessed by two trained spinal surgeons and statistically analyzed.Inter-reader reliability and agreement were assessed by interclass correlation coefficient.RESULTS The HUs decreased gradually from C2 to C7.The mean values of the left and right levels were significantly higher than those in the middle.Among the 51 patients,25 patients(49.02%)may be diagnosed with osteoporosis,and 16 patients(31.37%)may be diagnosed with osteopenia.CONCLUSION The HUs obtained by cervical spine CT are feasible for assessing bone mineral density with excellent agreement in AS patients with cervical fracture-dislocation. 展开更多
关键词 Hounsfield unit Ankylosing spondylitis FRACTURE-DISLOCATION Cervical spine OSTEOPOROSIS
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Bionic lightweight design of limb leg units for hydraulic quadruped robots by additive manufacturing and topology optimization
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作者 Huaizhi Zong Junhui Zhang +6 位作者 Lei Jiang Kun Zhang Jun Shen Zhenyu Lu Ke Wang Yanli Wang Bing Xu 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第1期1-13,共13页
Galloping cheetahs,climbing mountain goats,and load hauling horses all show desirable locomotion capability,which motivates the development of quadruped robots.Among various quadruped robots,hydraulically driven quadr... Galloping cheetahs,climbing mountain goats,and load hauling horses all show desirable locomotion capability,which motivates the development of quadruped robots.Among various quadruped robots,hydraulically driven quadruped robots show great potential in unstructured environments due to their discrete landing positions and large payloads.As the most critical movement unit of a quadruped robot,the limb leg unit(LLU)directly affects movement speed and reliability,and requires a compact and lightweight design.Inspired by the dexterous skeleton–muscle systems of cheetahs and humans,this paper proposes a highly integrated bionic actuator system for a better dynamic performance of an LLU.We propose that a cylinder barrel with multiple element interfaces and internal smooth channels is realized using metal additive manufacturing,and hybrid lattice structures are introduced into the lightweight design of the piston rod.In addition,additive manufacturing and topology optimization are incorporated to reduce the redundant material of the structural parts of the LLU.The mechanical properties of the actuator system are verified by numerical simulation and experiments,and the power density of the actuators is far greater than that of cheetah muscle.The mass of the optimized LLU is reduced by 24.5%,and the optimized LLU shows better response time performance when given a step signal,and presents a good trajectory tracking ability with the increase in motion frequency. 展开更多
关键词 Additive manufacturing Bionic lightweight design Limb leg unit Quadruped robot Trajectory tracking
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Improvement of the nutritional support management system for patients in intensive care units
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作者 Yuan-Yuan Zhang Chun-Yi Wang +5 位作者 Dong-Xian Guo Hai-Nu Gao Xian-Shan Jin Yan-Li Wu Lu-Han Chen Zhi-Xian Feng 《World Journal of Psychiatry》 SCIE 2024年第1期44-52,共9页
BACKGROUND Nutritional support for patients hospitalized in the intensive care unit(ICU)is an important part of clinical treatment and care,but there are significant implementation difficulties.AIM To introduce a modi... BACKGROUND Nutritional support for patients hospitalized in the intensive care unit(ICU)is an important part of clinical treatment and care,but there are significant implementation difficulties.AIM To introduce a modified nutritional support management system for ICU patients based on closed-loop information management and psychological counseling.METHODS The division of functions,personnel training,system construction,development of an intelligent decision-making software system,quality control,and improvement of the whole process were carried out to systematically manage nutritional support for ICU patients.RESULTS Following the implementation of the whole process management system,the scores of ICU medical staff’s knowledge,attitudes/beliefs,and practices regarding nutritional support were comprehensively enhanced.The proportion of hospital bed-days of total enteral nutrition(EN)in ICU patients increased from 5.58%to 11.46%,and the proportion of EN plus parenteral nutrition increased from 42.71%to 47.07%.The rate of EN initiation within 48 h of ICU admission increased from 37.50%to 48.28%,and the EN compliance rate within 72 h elevated from 20.59%to 31.72%.After the implementation of the project,the Self-rating Anxiety Scale score decreased from 61.07±9.91 points to 52.03±9.02 points,the Self-rating Depression Scale score reduced from 62.47±10.50 points to 56.34±9.83 points,and the ICU stay decreased from 5.76±2.77 d to 5.10±2.12 d.CONCLUSION The nutritional support management system based on closed-loop information management and psychological counseling achieved remarkable results in clinical applications in ICU patients. 展开更多
关键词 Closed-loop information Psychological counseling Intensive care unit patients Nutritional support Management system
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Epidemiology of carbapenem-resistant Acinetobacter baumannii colonization in neonatal intensive care units:A systematic review and meta-analysis
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作者 Donatien Serge Mbaga Sebastien Kenmoe +12 位作者 Seraphine Nkie Esemu Arnol Bowo-Ngandji Nene Kaah Keneh Jane-Francis Tatah Kihla Akoachere Hortense Kamga Gonsu Roland Ndip Ndip Jean Thierry Ebogo-Belobo Cyprien Kengne-Ndé Nicholas Tendongfor Jean Paul Assam Assam Lucy Mande Ndip Jacky Njiki Bikoï Sara Honorine Riwom Essama 《World Journal of Meta-Analysis》 2024年第1期1-10,共10页
BACKGROUND The rising prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)in neonatal intensive care units(NICUs)represents an escalating challenge in healthcare settings,particularly in managing hospital-... BACKGROUND The rising prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)in neonatal intensive care units(NICUs)represents an escalating challenge in healthcare settings,particularly in managing hospital-acquired infections(HAIs).Studies across various World Health Organization regions have documented a significant incidence of CRAB-related HAIs,with rates as high as 41.7 cases per 1000 patients in ICUs,accounting for 13.6%of all HAIs.These infections pose a doubled mortality risk compared to infections with carbapenem-susceptible Acinetobacter baumannii.A particularly concerning aspect of CRAB colonization is its asymptomatic nature,enabling its transmission through healthcare workers(HCWs)or the NICU environment to vulnerable neonates with developing immune systems.AIM To explore the prevalence of CRAB colonization in NICUs,focusing on neonates,healthcare workers,and the environmental samples,to enhance epidemiological understanding and inform targeted interventions.METHODS We conducted according to PRISMA 2020 checklist guidelines,a comprehensive literature search across multiple databases including MEDLINE(Ovid),EMBASE(Ovid),Global Health(Ovid),Web of Science,and Global Index Me-dicus.Studies were selected based on predetermined criteria,primarily involving neonates,HCWs,and environmental swabs,using culture or molecular methods to detect CRAB colonization.We excluded studies that did not specifically focus on NICUs,were duplicates,or lacked necessary data.The study selection and quality assessment were conducted independently by two reviewers.Data extraction involved collecting comprehensive details about each study.Our statistical analysis used a random-effects model to calculate the pooled prevalence and confidence intervals,stratifying results by regional location.We assessed study heterogeneity using Cochran's Q statistic and I²statistic,with regression tests employed to evaluate potential publication bias.RESULTS We analyzed 737 records from five databases,ultimately including 13 studies from ten countries.For neonates,the pooled prevalence was 4.8%(95%CI:1.1%to 10.5%)with the highest rates observed in South-East Asia(10.5%;95%CI:2.4%to 23.3%).Among HCWs,a single Indian study reported a 3.3%prevalence.Environmental samples showed a prevalence of 2.3%(95%CI:0%to 9.3%),with the highest rates in South-East Asia(10%;95%CI:4.2%to 17.7%).Significant heterogeneity was found across studies,and no publication bias was detected.CONCLUSION This systematic review highlights a significant prevalence of CRAB colonization in neonates across various regions,particularly in South-East Asia,contrasting with lower rates in high-income countries.The study reveals a gap in research on HCWs colonization,with only a single study from India reporting moderate prevalence.Environmental samples indicate moderate levels of CRAB contamination,again higher in South-East Asia.These findings underscore the need for more extensive and focused research on CRAB colonization in NICUs,including exploring the roles of HCWs and the environment in transmission,understanding antimicrobial resistance patterns,and developing effective prevention measures. 展开更多
关键词 COLONIZATION Carbapenem-resistant Acinetobacter baumannii Neonatal intensive-care unit
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Temperature Trends and Accumulation of Chill Hours, Chill Units, and Chill Portions in South Carolina
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作者 José O. Payero 《Atmospheric and Climate Sciences》 2024年第2期173-190,共18页
There is considerable concern about the potential impact of climate change on agriculture, such as the accumulation of chilling hours needed to break the dormancy of many perennial plants, like fruit trees. Therefore,... There is considerable concern about the potential impact of climate change on agriculture, such as the accumulation of chilling hours needed to break the dormancy of many perennial plants, like fruit trees. Therefore, this study aimed to determine if there had been a significant change in air temperatures and chill hours, chill units, and chill portion accumulation in South Carolina over the last two decades. Two decades of daily maximum (T<sub>max</sub>) and minimum (T<sub>min</sub>) air temperature records were obtained from weather stations in thirty-one counties in South Carolina. Hourly temperature data, reconstructed from the daily data, were used to calculate the daily and annual chill hours, chill units, and chill portions accumulation using four different chill models for each location and year. The chill models included the T(t) °C model, the 0°C °C model, the Utah model, and the Dynamic model. For each county, regression analyses were conducted to evaluate the historical trends. Despite year-to-year variability, the tendency was a statistically significant (α = 0.05) increase in air temperature, averaging 0.089°C per year for 20 out of 31 counties in South Carolina. The other 11 counties had no significant change in temperature. The average temperature increase in the 31 counties was 0.072°C per year. The temperature increase resulted in a decrease in annual chill accumulation during the fall to spring, averaging 17.7 chill hours, 8.6 chill hours, 17.0 chill units, and 0.40 chill portions per year calculated with the T(t) °C, 0°C °C, Utah, and Dynamic models, respectively. However, whether this decrease in chill values was statistically significant or not depended on the chill model used. This study did not investigate the cause of the observed historical trends in temperature and chill accumulation. Still, if the trends continue, they could significantly impact the future of the temperate fruit tree industry in the state. 展开更多
关键词 Chill Hours Chill units Chill Portions TEMPERATURE Fruit Trees Climate Change DORMANCY
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Improved Units of Measure in Rotational Mechanics
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作者 Richard James Petti 《World Journal of Mechanics》 2024年第1期1-7,共7页
The SI system of units in rotational mechanics yields correct numerical results, but it produces physically incorrect units of measure in many cases. SI units also violate the principle of general covariance—the gene... The SI system of units in rotational mechanics yields correct numerical results, but it produces physically incorrect units of measure in many cases. SI units also violate the principle of general covariance—the general rule for defining continuous coordinates and units in mathematics and mathematical physics. After 30+ years of wrestling with these problems, the ultimate authority on units of measure has declared that Newton–meter and Joule are not equivalent in rotational mechanics, as they are in the rest of physics. This article proposes a simple modification to SI units called “Nonstandard International units” (“NI units”) until a better name is agreed upon. NI units yield correct numerical results and physically correct units of measure, and they satisfy the principle of general covariance. The main obstacle to the adoption of NI units is the consensus among users that the radius of rotation should have the unit meter because the radius can be measured with a ruler. NI units assigned to radius should have units meter/radian because the radius is a conversion factor between angular size and circumferential length, as in arclength = rθ. To manage the social consensus behind SI units, the author recommends retaining SI units as they are, and informing users who want correct units that NI units solve the technical problems of SI units. 展开更多
关键词 Rotational Mechanics Angular Unit TORQUE Moment of Inertia Angular Momentum General Covariance
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A novel method for integrating chromatographic fingerprint analytical units of Chinese materia medica:the matching frequency statistical moment method
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作者 LI Haiying PAN Xue +4 位作者 WANG Mincun LI Wenjiao HE Peng HUANG Sheng HE Fuyuan 《Digital Chinese Medicine》 CAS CSCD 2024年第3期294-308,共15页
Objective To facilitate the quality evaluation suitable for the unique characteristics of Chinese materia medica(CMM)by developing and implementing a novel approach known as the matching frequency statistical moment(M... Objective To facilitate the quality evaluation suitable for the unique characteristics of Chinese materia medica(CMM)by developing and implementing a novel approach known as the matching frequency statistical moment(MFSM)method.Methods This study established the MFSM method.To demonstrate its effectiveness,we applied this novel approach to analyze Danxi Granules(丹膝颗粒,DXG)and its constituent herbal materials.To begin with,the ultra-performance liquid chromatography(UPLC)was applied to obtain the chromatographic fingerprints of DXG and its constituent herbal materi-als.Next,the MFSM was leveraged to compress and integrate them into a new fingerprint with fewer analytical units.Then,we characterized the properties and variability of both the original and integrated fingerprints by calculating total quantum statistical moment(TQSM)parameters,information entropy and information amount,along with their relative standard deviation(RSD).Finally,we compared the TQSM parameters,information entropy and infor-mation amount,and their RSD between the traditional and novel fingerprints to validate the new analytical method.Results The chromatographic peaks of DXG and its 12 raw herbal materials were divided and integrated into peak families by the MFSM method.Before integration,the ranges of the peak number,three TQSM parameters,information entropy and information amount for each peak or peak family of UPLC fingerprints of DXG and its 12 raw herbal materials were 95.07−209.73,9390−183064μv·s,5.928−21.33 min,22.62−106.69 min^(2),4.230−6.539,and 50530−974186μv·s,respectively.After integration,the ranges of these parameters were 10.00−88.00,9390−183064μv·s,5.951−22.02 min,22.27−104.73 min^(2),2.223−5.277,and 38159−807200μv·s,respectively.Correspondingly,the RSD of all the aforementioned pa-rameters before integration were 2.12%−9.15%,6.04%−49.78%,1.15%−23.10%,3.97%−25.79%,1.49%−19.86%,and 6.64%−51.20%,respectively.However,after integration,they changed to 0.00%,6.04%−49.87%,1.73%−23.02%,3.84%−26.85%,1.17%−16.54%,and 6.40%−48.59%,respectively.The results demonstrated that in the newly integrated fingerprint,the analytical units of constituent herbal materials,information entropy and information amount were significantly reduced(P<0.05),while the TQSM parameters remained unchanged(P>0.05).Additionally,the RSD of the TQSM parameters,information entropy,and information amount didn’t show significant difference before and after integration(P>0.05),but the RSD of the number and area of the integrated analytical units significantly decreased(P<0.05).Conclusion The MFSM method could reduce the analytical units of constituent herbal mate-rials while maintain the properties and variability from their original fingerprint.Thus,it could serve as a feasible and reliable tool to reduce difficulties in analyzing multi-compo-nents within CMMs and facilitating the evaluation of their quality. 展开更多
关键词 Chromatographic fingerprints Analytical units Matching frequency statistical moment method Chinese materia medica Danxi Granule(丹膝颗粒 DXG) Quality evaluation
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A Deep Learning-Based Teaching Design for High School Geography Units:Taking the Example of Landforms of the Humanistic Education Edition
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作者 Xiaojie Yuan Chenguang Zhang +3 位作者 Jiajia Li Jiqiang Niu Xiumei Li Xingjun Shi 《Journal of Contemporary Educational Research》 2024年第2期176-182,共7页
The traditional teaching methods of one-way cultivation of students can no longer meet the requirements of talent cultivation at this stage.The issue of how to promote students from passive acceptance to the independe... The traditional teaching methods of one-way cultivation of students can no longer meet the requirements of talent cultivation at this stage.The issue of how to promote students from passive acceptance to the independent cognitive understanding stage(i.e.deep learning)has become the focus of geography teaching.Therefore,under the guidance of deep learning theory,this paper takes the“landforms”knowledge unit of the Humanistic Education Edition as an example,improves the classroom teaching means through the unit teaching mode,reconstructs the“landforms”teaching unit,and explores the specific teaching of high school geography unit based on deep learning.This study provides a good example and guidelines for high school geography teaching and learning. 展开更多
关键词 Deep learning Unit teaching Geography education Case design High school education
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光伏发电机组异动信息主动增量式更新算法
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作者 王晖 赵咨钧 +1 位作者 管保晋 曲诺亚 《电子设计工程》 2025年第1期132-136,共5页
针对进行光伏发电机组密集型异动信息更新操作时,出现更新时延长、更新结果不完整的问题,提出了光伏发电机组异动信息主动增量式更新算法。通过特征提取、小波变换和模极大值计算来获取有效的增量式特征;构建增量特征成词袋模型并进行标... 针对进行光伏发电机组密集型异动信息更新操作时,出现更新时延长、更新结果不完整的问题,提出了光伏发电机组异动信息主动增量式更新算法。通过特征提取、小波变换和模极大值计算来获取有效的增量式特征;构建增量特征成词袋模型并进行标注;结合蚁群算法搜索异动信息,计算最小平均带宽和最佳更新路径,通过动态更新相容类和决策类异动信息完善数据;采用2阶段集合式更新方案进行信息增量收集和校验增量分发,以获取主动增量式更新异动信息。由实验结果可知,该算法更新时延在全部校验节点下未超过40 s,且能够保证更新结果具有完整性。 展开更多
关键词 光伏发电机组 异动信息 主动增量式 更新
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随机DMU相对有效性评价的期望值方法及其应用 被引量:6
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作者 曾祥云 吴育华 《系统工程学报》 CSCD 2000年第3期247-252,共6页
DEA的随机性研究是目前 DEA理论研究的前沿。本文基于随机条件下决策单元期望有效性指数的概念 ,提出了随机 DMU相对有效性评价的期望值方法 ,给出了随机 DMU相对有效的两个定义 。
关键词 有效性评价 期望值方法 随机dmu DEA
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一种低成本GPS/DMU组合系统研究 被引量:1
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作者 岳晓奎 袁建平 郑谔 《宇航学报》 EI CAS CSCD 北大核心 2000年第z1期66-69,共4页
基于新型的低成本微型固态惯性测量单元 - DMU( Dynamic Measurement Unit)和GPS系统 ,利用具有良好鲁棒性能的 H∞ 滤波算法 ,设计了一种低成本 GPS/DMU组合导航系统。通过仿真计算对该组合系统的性能进行了分析 ,结果表明 ,新型的组... 基于新型的低成本微型固态惯性测量单元 - DMU( Dynamic Measurement Unit)和GPS系统 ,利用具有良好鲁棒性能的 H∞ 滤波算法 ,设计了一种低成本 GPS/DMU组合导航系统。通过仿真计算对该组合系统的性能进行了分析 ,结果表明 ,新型的组合系统不仅具有良好的性能价格比 ,而且体积小、具有更强的稳定性能 。 展开更多
关键词 GPS dmu H∞滤波器 鲁棒性 组合导航
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数据包络分析(DEA)中DMU的分类定理 被引量:4
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作者 朱乔 盛昭瀚 《系统工程学报》 CSCD 1994年第1期41-45,共5页
依Charnes等的DMU分类思路,给出一种新的DMU分类手段及理论依据。
关键词 数据包络分析 分类 dmu 线性包络模型
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基于DMU异质性的DEA研究述评及展望 被引量:1
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作者 鲁涛 周晶 《生产力研究》 CSSCI 北大核心 2010年第2期251-253,共3页
经典DEA模型假定DMU应具同质性,但人们常发现其实践中显示异质性,如用经典DEA模型对异质性DMU进行评价,往往出现偏差。已有DEA研究重点在于模型拓展,而非评价对象,因此均基于DMU同质,而对DMU异质性情况研究较少。文章则力图从另一视角... 经典DEA模型假定DMU应具同质性,但人们常发现其实践中显示异质性,如用经典DEA模型对异质性DMU进行评价,往往出现偏差。已有DEA研究重点在于模型拓展,而非评价对象,因此均基于DMU同质,而对DMU异质性情况研究较少。文章则力图从另一视角对基于DMU异质性的DEA研究进行述评及展望。 展开更多
关键词 dmu异质性 DEA 述评 展望
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Study on Various Rectifiers for Fan-Filter Units 被引量:3
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作者 刘俊杰 涂光备 马九贤 《Transactions of Tianjin University》 EI CAS 2002年第2期119-124,共6页
The face velocities of the high efficiency particulate air filters and the ultra low penetration airfilters in fan filter units (FFUs) have large relative standard deviation and turbulivity. It seriously affects the ... The face velocities of the high efficiency particulate air filters and the ultra low penetration airfilters in fan filter units (FFUs) have large relative standard deviation and turbulivity. It seriously affects the unidirectivity of the flow in the unidirectional flow clean zone and cleanroom. The cross contamination in this kind of unidirectional flow area is hardly controlled. It is significant to find optional method for keeping the face velocity uniformity of FFU and reducing the face velocity turbulivity of FFU, furthermore, to keep the cleanliness level under FFUs. The normal and easy method is to add flow rectifiers under filters. FFUs with various flow rectifiers have been tested. The uniformity and turbulivity of facevelocity under the FFU are presented in this paper. The influence of the facevelocity uniformity and turbulivity on the contamination boundary of the unidirectional flow is studiedas well. 展开更多
关键词 unidirectional flow air velocity UNIFORMITY turbulivity flow rectifier fan filter unit (FFU)
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DMU50 eVolution非正交五轴机床的后置处理研究 被引量:1
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作者 石勇 刘文涛 廖江 《机械设计》 CSCD 北大核心 2012年第2期8-10,15,共4页
由于DMU50 eVolution五轴加工机床具有高精度、高性价比,因此被广泛使用。然而机床工作台的B轴与机床的Y轴不重合,属于非正交结构,使得加工程序的后置处理相对困难。通过对双转台五轴机床开展结构分析,对任意刀具轨迹数据点,先求解出机... 由于DMU50 eVolution五轴加工机床具有高精度、高性价比,因此被广泛使用。然而机床工作台的B轴与机床的Y轴不重合,属于非正交结构,使得加工程序的后置处理相对困难。通过对双转台五轴机床开展结构分析,对任意刀具轨迹数据点,先求解出机床双转台的B轴和C轴后置处理转角大小,然后利用求解出的转角大小,通过坐标变换,求解出该刀具轨迹数据点对应的机床位置。利用后置处理算法开发了DMU50 eVolution五轴机床程序后置处理软件,该软件可将UG软件编制的加工程序转换为通用G代码程序。 展开更多
关键词 dmu50 后置处理 五轴联动 双转台
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