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Mediating role of health literacy in the relationship between social isolation and psychological distress among pre-frail older adults
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作者 Juan Fang Li-Hui Li +4 位作者 Ming-Qian He Yue Ji Dong-Yan Lu Li-Bing Zhang Jin-Lan Yao 《World Journal of Psychiatry》 SCIE 2025年第1期137-144,共8页
BACKGROUND Frailty has become a significant public health issue.The recent increase in the number of frail older adults has led to increased attention being paid to psycho-logical care services in communities.The soci... BACKGROUND Frailty has become a significant public health issue.The recent increase in the number of frail older adults has led to increased attention being paid to psycho-logical care services in communities.The social isolation of pre-frail older adults can impact their psychological distress.AIM To explore the mediating effect of health literacy between social isolation and psychological distress among communitydwelling older adults with pre-frailty.METHODS This descriptive cross-sectional study was conducted with 254 pre-frail older individuals aged 60 years and over.Social isolation,health literacy,and psycholo-gical distress were comprehensively measured using the Lubben Social Network Scale-6,12-item Short-Form Health Literacy Questionnaire,and the Kessler Psy-chological Distress Scale-10.Data were evaluated using the SPSS 27.0 package program and the PROCESS macro tool.Descriptive statistical analyses,correlation analyses,and bootstrap mediation tests were used to assess associations between the variables.RESULTS The results showed that social isolation had an effect on health literacy among pre-frail older adults(β=0.240,P<0.001),social isolation impact on psycho-logical distress pre-frail older adults(β=-0.415,P<0.001);health literacy was identified effect on psychological distress among pre-frail older persons(β=-0.307,P<0.001).Health literacy partially mediated the relationship between social isolation and psychological distress among community-dwelling older adults with pre-frailty,with a mediation effect of-0.074,accounting for 17.83%of the total effect. 展开更多
关键词 FRAIL Ageing Psychological distress Health literacy Social isolation
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Impact of surface-reflected seismic waves on the seismic isolation performance of circular tunnel isolation layers 被引量:1
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作者 LU Jiahui LUO Junjie +3 位作者 HUANG Xiangyun HONG Junliang HE YanXin ZHOU Fulin 《Journal of Mountain Science》 SCIE CSCD 2024年第3期901-917,共17页
Seismic isolation is an effective strategy to mitigate the risk of seismic damage in tunnels.However,the impact of surface-reflected seismic waves on the effectiveness of tunnel isolation layers remains under explored... Seismic isolation is an effective strategy to mitigate the risk of seismic damage in tunnels.However,the impact of surface-reflected seismic waves on the effectiveness of tunnel isolation layers remains under explored.In this study,we employ the wave function expansion method to provide analytical solutions for the dynamic responses of linings in an elastic half-space and an infinite elastic space.By comparing the results of the two models,we investigate the seismic isolation effect of tunnel isolation layers induced by reflected seismic waves.Our findings reveal significant differences in the dynamic responses of the lining in the elastic half-space and the infinitely elastic space.Specifically,the dynamic stress concentration factor(DSCF)of the lining in the elastic half-space exhibits periodic fluctuations,influenced by the incident wave frequency and tunnel depth,while the DSCF in the infinitely elastic space remain stable.Overall,the seismic isolation application of the tunnel isolation layer is found to be less affected by surface-reflected seismic waves.Our results provide valuable insights for the design and assessment of the seismic isolation effect of tunnel isolation layers. 展开更多
关键词 Circular tunnel seismic isolation Surface reflection Response of liners Wave-function expansion method
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A viscoelastic metamaterial beam for integrated vibration isolation and energy harvesting
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作者 Long ZHAO Zeqi LU +1 位作者 Hu DING Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第7期1243-1260,共18页
Locally resonant metamaterials have low-frequency band gaps and the capability of converging vibratory energy in the band gaps at resonant cells.It has been demonstrated by several researchers that the dissipatioin of... Locally resonant metamaterials have low-frequency band gaps and the capability of converging vibratory energy in the band gaps at resonant cells.It has been demonstrated by several researchers that the dissipatioin of vibratory energy within the band gap can be improved by using viscoelastic materials.This paper designs an integrated viscoelastic metamaterial for energy harvesting and vibration isolation.The viscoelastic metamaterial is achieved by a viscoelastic beam periodically arrayed with spatial ball-pendulum nonlinear energy harvesters.The nonlinear resonator with an energy harvesting function is achieved by placing a free-rolling magnetic ball in a spherical cavity with an additional induction coil.The dynamic equations of viscoelastic metamaterials under transverse excitation are established,and the energy harvesting and vibration isolation characteristics within the dispersion relation of viscoelastic metamaterials are analyzed.The results show that the vibrations of the main body of the viscoelastic metamaterial beam are significantly suppressed in the frequency range of the local resonance band gap.At the same time,the elastic waves are limited in the nonlinear resonator with an energy harvesting function,which improves the energy output.Finally,an experimental platform of viscoelastic metamaterial vibration is established for validation purposes. 展开更多
关键词 viscoelastic metamaterial nonlinear vibration vibration isolation energy harvesting
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Dynamic analysis of a novel multilink-spring mechanism for vibration isolation and energy harvesting
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作者 谢佳衡 杨涛 唐介 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期366-379,共14页
Due to technical limitations,existing vibration isolation and energy harvesting(VIEH)devices have poor performance at low frequency.This paper proposes a new multilink-spring mechanism(MLSM)that can be used to solve t... Due to technical limitations,existing vibration isolation and energy harvesting(VIEH)devices have poor performance at low frequency.This paper proposes a new multilink-spring mechanism(MLSM)that can be used to solve this problem.The VIEH performance of the MLSM under harmonic excitation and Gaussian white noise was analyzed.It was found that the MLSM has good vibration isolation performance for low-frequency isolation and the frequency band can be widened by adjusting parameters to achieve a higher energy harvesting power.By comparison with two special cases,the results show that the MLSM is basically the same as the other two oscillators in terms of vibration isolation but has better energy harvesting performance under multistable characteristics.The MLSM is expected to reduce the impact of vibration on high-precision sensitive equipment in some special sites such as subways and mines,and at the same time supply power to structural health monitoring devices. 展开更多
关键词 multilink-spring mechanism nonlinear dynamics vibration isolation energy harvester
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Multi-layer quasi-zero-stiffness meta-structure for high-efficiency vibration isolation at low frequency
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作者 Jiahao ZHOU Jiaxi ZHOU +3 位作者 Hongbin PAN Kai WANG Changqi CAI Guilin WEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第7期1189-1208,共20页
An easily stackable multi-layer quasi-zero-stiffness(ML-QZS)meta-structure is proposed to achieve highly efficient vibration isolation performance at low frequency.First,the distributed shape optimization method is us... An easily stackable multi-layer quasi-zero-stiffness(ML-QZS)meta-structure is proposed to achieve highly efficient vibration isolation performance at low frequency.First,the distributed shape optimization method is used to design the unit cel,i.e.,the single-layer QZS(SL-QZS)meta-structure.Second,the stiffness feature of the unit cell is investigated and verified through static experiments.Third,the unit cells are stacked one by one along the direction of vibration isolation,and thus the ML-QZS meta-structure is constructed.Fourth,the dynamic modeling of the ML-QZS vibration isolation metastructure is conducted,and the dynamic responses are obtained from the equations of motion,and verified by finite element(FE)simulations.Finally,a prototype of the ML-QZS vibration isolation meta-structure is fabricated by additive manufacturing,and the vibration isolation performance is evaluated experimentally.The results show that the vibration isolation performance substantially enhances when the number of unit cells increases.More importantly,the ML-QZS meta-structure can be easily extended in the direction of vibration isolation when the unit cells are properly stacked.Hence,the ML-FQZS vibration isolation meta-structure should be a fascinating solution for highly efficient vibration isolation performance at low frequency. 展开更多
关键词 quasi-zero stiffness(QZS) meta-structure high efficiency low frequency vibration isolation
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Female zebra finches are more vulnerable to social isolation stress than males:Involvement of the nonapeptide system
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作者 Limin Wang Zhuang Hao +6 位作者 Lirong Zuo Tianyu Xing Xuan Peng Ghulam Nabi John C.Wingfield Fumin Lei Dongming Li 《Zoological Research》 SCIE CSCD 2024年第6期1300-1312,共13页
In group-living animals,chronic juvenile social isolation stress(SIS)can profoundly affect behavior and neuroendocrine regulation.However,its impact on social behavior in avian species,particularly regarding sexspecif... In group-living animals,chronic juvenile social isolation stress(SIS)can profoundly affect behavior and neuroendocrine regulation.However,its impact on social behavior in avian species,particularly regarding sexspecific neural circuit differences,remains underexplored.This study focused on zebra finches,a species known for its social clustering and cognitive abilities,to elucidate these influences.Results indicated that SIS significantly increased plasma corticosterone levels in females but not in males,suggesting a heightened stress response and susceptibility in females.Additionally,SIS disrupted sociality and flocking behavior in both sexes,with more severe impairments in social recognition observed in females.Mesotocin(MT)levels in the lateral septum of both sexes and in the ventromedial hypothalamus of females were found to mediate the SIS effect,while vasotocin(VT)levels within the social behavior network remained unchanged.Pharmacological interventions confirmed the critical role of MT in reversing SIS-induced impairments in sociality,flocking behavior,and social recognition,particularly in females.These findings highlight unique nucleus-and sex-dependent variations in MT and VT regulation,providing novel insights into the mechanisms governing avian social behavior.This study advances our understanding of the independent evolutionary pathways of neural circuits and neuroendocrine systems that modulate social behaviors across different taxonomic groups. 展开更多
关键词 Nonapeptide system Sex differences Social behavior Social isolation stress Taeniopygia guttata
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Seismic control of multi-degrees-of-freedom structures by vertical mass isolation method using MR dampers
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作者 Mohamad Shahrokh Abdi Masoud Nekooei Mohammad-Ali Jafari 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期503-510,共8页
Vertical mass isolation(VMI)is one of the novel methods for the seismic control of structures.In this method,the entire structure is assumed to consist of two mass and stiffness subsystems,and an isolated layer is loc... Vertical mass isolation(VMI)is one of the novel methods for the seismic control of structures.In this method,the entire structure is assumed to consist of two mass and stiffness subsystems,and an isolated layer is located among them.In this study,the magnetorheological damper in three modes:passive-off,passive-on,and semi-active mode with variable voltage between zero and 9 volts was used as an isolated layer between two subsystems.Multi-degrees-of-freedom structures with 5,10,and 15 floors in two dimensions were examined under 11 pairs of near field earthquakes.On each level,the displacement of MR dampers was taken into account.The responses of maximum displacement,maximum inter-story drift,and maximum base shear in controlled and uncontrolled buildings were compared to assess the suggested approach for seismic control of the structures.According to the results,the semi-active control method can reduce the response by more than 12%compared to the uncontrolled mode in terms of maximum displacement of the mass subsystem of the structures.This method can reduce more than 16%and 20%of the responses compared to the uncontrolled mode in terms of maximum inter-story drift and base shear of the structure,respectively. 展开更多
关键词 seismic control vertical mass isolation base shear magnetorheological damper semi-active control
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Ultrasound-assisted isolation:A new method to isolate stromal vascular fraction
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作者 Yiming Gao Xiaojie Zhang +5 位作者 Poh-Ching Tan Yun Xie Peiqi Zhang Tianyu Zhang Qingfeng Li Shuangbai Zhou 《Chinese Journal of Plastic and Reconstructive Surgery》 2024年第1期8-15,共8页
Background:The stromal vascular fraction(SVF),a cluster of stem and progenitor cells isolated from adipose tissue,holds significant promise for application in regenerative medicine.However,the existing methods for SVF... Background:The stromal vascular fraction(SVF),a cluster of stem and progenitor cells isolated from adipose tissue,holds significant promise for application in regenerative medicine.However,the existing methods for SVF isolation are time-consuming and expensive.Thus,in this study,we explored a new method of SVF extrac-tion-ultrasound-assisted SVF isolation(USASI)-and compared the viability and characteristics of SVF isolated using different methods.Methods:SVF extraction methods using different combinations of ultrasound power,ultrasound time,collagenase dosage,and collagenase digestion time were compared with those of the control group(collagenase digestion method).The cell yield and vitality of the SVF were evaluated via cell counting and trypan blue staining.The cell components and immunophenotypes of freshly isolated SVF were analyzed using flow cytometry.The prolifer-ative capacity and differentiation potential of the SVF were also identified.Results:Ultrasonication at 95 W-20 kHz for 30 s followed by digestion with 0.15%collagenase for 30 min was identified as the most suitable parameter for the USASI method in isolating SVF,as recommended based on the evaluation of various tested conditions.The USASI method significantly reduced the collagenase dosage and shortened the digestion time.Compared to the collagenase digestion method,the USASI method had a higher cell yield and cell viability,with no adverse effects on cell components,proliferative capacity,or multipotential differentiation capacity.Conclusion:With reduced processing time,lower collagenase dosage,and increased cell yield without impairing the viability and characteristics of SVF,USASI holds the potential to emerge as a time-saving and cost-effective method for future clinical applications. 展开更多
关键词 Stromal vascular fractions SVF isolation Mechanical force ULTRASOUND
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Identification,Isolation and Genomic Characterization of Porcine Astrovirus in Shandong Province,China in 2021-2023
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作者 Liu Yueyuel Zhang Yu +7 位作者 Zhu Yuwei Guo Xiaozhen Yang Shifa Yin Bin Zhao Zengcheng Huang Zhonglil Wu Jiaqiang Lin Shuqian 《Animal Husbandry and Feed Science》 CAS 2024年第1期13-20,共8页
[Objective]The paper was to identify,isolate,and characterize porcine astrovirus in Shandong Province between 2021 and 2023.[Method]A total of 1025 samples of porcine diarrhea samples were collected from various regio... [Objective]The paper was to identify,isolate,and characterize porcine astrovirus in Shandong Province between 2021 and 2023.[Method]A total of 1025 samples of porcine diarrhea samples were collected from various regions of Shandong Province between January 2021 and October 2023.The samples were tested by RT-PCR,followed by sequencing and phylogenetic analyses of the polymerase.[Result]The total positive rate of PAstV was 34.6%(355/1025).The respective proportions of individuals infected with PAstV-1,PAstV-2,PAstV-4 and PAstV-5 were 25.4%(90/355),28.2%(100/355),35.2%(125/355)and 22.5%(80/355),respectively.Additionally,mixed infection was observed.Meanwhile,849 samples of healthy pigs were tested by RT-PCR,and the results demonstrated that the total positive rate of PAstV was 8.13%(69/849).Of these,the proportion of PAstV-1,PAstV-2 and PAstV-4 infection was 27.5%(19/69),37.7%(26/69)and 40.6%(28/69),and a mixed infection also existed.Further sequencing and characterization of some the selected isolates revealed low sequence identities(56.2%)with known PAstV strains,indicating the presence of novel types or genotypes of PAstVs.Furthermore,the isolation conditions of porcine astrovirus were optimized,resulting in the purification of a pure PAstV-4 strain(designated PAstV-4-GRF1).The virus was found to exhibit typical astroviral morphology,with nucleotide identity ranging from 89.9 to 95.4%with previously published PAstV-4 strains.Then,macrovirus transcriptome sequencing showed that 88.30%of the CRF1 samples were mammalian astroviruses.By species classification,PAstV 4 and PAstV 2 accounted for 21.79%and 0.32%,respectively.Phylogenetic tree analysis showed that the c15050 fragment was identical to the GRF-1 sequencing fragment of the isolated strain,and exhibited the highest homology with the Hunan PAstV-4 sequence MK460231 in China.[Conclusion]As the inaugural isolated PAstV-4 strain,it furnishes pivotal materialfor the investigation ofthe biological and pathogenic properties of this virus as well as for the prospectivedevelopment of relevant biological and diagnostic reagents. 展开更多
关键词 Porcine astrovirus Epidemic situation Genotype analysis isolation and identification
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Near resonance vibration isolation on a levered-dual response(LEDAR)Coulomb-damped system by differential preloads/offsets in linear springs
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作者 T.I.TOLUWALOJU C.K.THEIN D.HALIM 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期1033-1050,共18页
The levered-dual response(LEDAR)Coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear springs.It takes the advantages of both the preloads/offsets in linear springs... The levered-dual response(LEDAR)Coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear springs.It takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration isolation.The isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without guiderails.The compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential threshold.The isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate connector.The observed near resonant isolation thus makes the LEDAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies. 展开更多
关键词 lever ratio Coulomb damping preload tension/compression isolation band/depth offset potential
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Refining adipose-derived stem cell isolation for optimal regenerative therapy
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作者 Chun-Han Cheng Wen-Rui Hao Tzu-Hurng Cheng 《World Journal of Stem Cells》 SCIE 2024年第11期978-984,共7页
This article highlights the importance of optimizing the techniques used for isolating stromal vascular fraction cells from adipose tissue.Furthermore,by presenting key findings from the literature,it clarifies the ef... This article highlights the importance of optimizing the techniques used for isolating stromal vascular fraction cells from adipose tissue.Furthermore,by presenting key findings from the literature,it clarifies the effects of refined techniques on regenerative medicine and advocates for ongoing research and innovation to enhance therapeutic outcomes. 展开更多
关键词 Stromal vascular fraction Adipose-derived stem cell Regenerative medicine isolation technique Mesenchymal stem cell
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Actuator and sensor fault isolation in a class of nonlinear dynamical systems
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作者 Hamed Tirandaz Christodoulos Keliris Marios M.Polycarpou 《Journal of Automation and Intelligence》 2024年第2期57-72,共16页
Fault isolation in dynamical systems is a challenging task due to modeling uncertainty and measurement noise,interactive effects of multiple faults and fault propagation.This paper proposes a unified approach for isol... Fault isolation in dynamical systems is a challenging task due to modeling uncertainty and measurement noise,interactive effects of multiple faults and fault propagation.This paper proposes a unified approach for isolation of multiple actuator or sensor faults in a class of nonlinear uncertain dynamical systems.Actuator and sensor fault isolation are accomplished in two independent modules,that monitor the system and are able to isolate the potential faulty actuator(s)or sensor(s).For the sensor fault isolation(SFI)case,a module is designed which monitors the system and utilizes an adaptive isolation threshold on the output residuals computed via a nonlinear estimation scheme that allows the isolation of single/multiple faulty sensor(s).For the actuator fault isolation(AFI)case,a second module is designed,which utilizes a learning-based scheme for adaptive approximation of faulty actuator(s)and,based on a reasoning decision logic and suitably designed AFI thresholds,the faulty actuator(s)set can be determined.The effectiveness of the proposed fault isolation approach developed in this paper is demonstrated through a simulation example. 展开更多
关键词 Actuator and sensor fault isolation Adaptive approximation Observer-based fault diagnosis Reasoning-based decision logic
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Isolation and Identification of Beta-Carotene from Carrots
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作者 Aida Smajlagić Majda Srabović +5 位作者 Melita Huremović Ekrem Pehlić Zahida Ademović Ermina-Čilović Kozarević Merima Ibišević Jasmina Siočić 《Open Journal of Applied Sciences》 2024年第11期2996-3003,共8页
Carotenoids are a group of natural pigments that are isolated from plants and are known for their great importance in maintaining human health. Beta-carotene is an organic compound, from yellow to red-orange colour, w... Carotenoids are a group of natural pigments that are isolated from plants and are known for their great importance in maintaining human health. Beta-carotene is an organic compound, from yellow to red-orange colour, which is found in many plants, fruits and vegetables. All carotenoids, especially beta-carotene, which is the subject of this research, are used in the pharmaceutical, food and cosmetic industries. It is also important in medicine as it prevents the occurrence of many diseases. Beta-carotene is a precursor of vitamin A and is used in various research due to its strong antioxidant effect. The highest amount of beta-carotene is found in carrots, followed by apricots, tomatoes, asparagus, broccoli, pumpkins, plums, etc. This plant pigment was isolated from carrots using a reflux extraction method using the organic solvents methanol and methylene chloride. The isolated carotenoid was confirmed by UV, TLC, FTIR, and HPLC methods. The absorption maxima of the UV spectrum of the isolated compound (β-carotene) range from 200 to 280 nm and 400 to 500 nm. The identification of beta-carotene was done by analysis using the FTIR method, where functional groups that are present indicate the isolated compound. HPLC method is rapid, effective and sensitive for carotenoid analysis. Analysis of the HPLC method confirms the isolated compound with an absorption maximum of 448 nm, which was compared with the standard. 展开更多
关键词 Carotenoids isolation Beta-Carotene UV TLC FTIR HPLC
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No-touch isolation technique in emergency pancreaticoduodenectomy for neoplastic hemorrhage: Two case reports and review of literature
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作者 Akihiro Cho Satoshi Katagiri +8 位作者 Masao Ota Shunsuke Onizawa Ryota Higuchi Toshiya Sugishita Yukiko Niwa Takeshi Ishita Toshihiko Mouri Akita Kato Moe Iwata 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1910-1917,共8页
BACKGROUND Emergency pancreaticoduodenectomy(EPD)is a rare event for complex periam-pullary etiology.Increased intraoperative blood loss is correlated with poor post-operative outcomes.CASE SUMMARY Two patients underw... BACKGROUND Emergency pancreaticoduodenectomy(EPD)is a rare event for complex periam-pullary etiology.Increased intraoperative blood loss is correlated with poor post-operative outcomes.CASE SUMMARY Two patients underwent EPD using a no-touch isolation technique,in which all arteries supplying the pancreatic head region were ligated and divided before manipulation of the pancreatic head and duodenum.The operative times were 220 and 239 min,and the blood loss was 70 and 270 g,respectively.The patients were discharged on the 14^(th) and 10^(th) postoperative day,respectively.Thirty-two patients underwent EPD for the treatment of neoplastic bleeding.The mean operative time was 361.6 min,and the mean blood loss was 747.3 g.The comp-lication rate was 37.5%.The in-hospital mortality rate was 9.38%.CONCLUSION The no-touch isolation technique is feasible,safe,and effective for reducing intraoperative blood loss in EPD. 展开更多
关键词 No-touch isolation technique PANCREATICODUODENECTOMY Emergency pancre-aticoduodenectomy Neoplastic bleeding Superior mesenteric artery first approach Case report
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Optimization of Cellulose Nanocrystal Isolation from Ayous Sawdust Using Response Surface Methodology
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作者 Tchigo Alifa Hamida Aminatou +1 位作者 Oumar Said Jean-Bosco Tchatchueng 《Journal of Materials Science and Chemical Engineering》 2024年第1期36-55,共20页
This study focuses on the extraction of cellulose nanocrystals (CNC), from microcrystalline cellulose (MCC), derived from Ayous sawdust. The process involves multiple steps and a large amount of chemical products. The... This study focuses on the extraction of cellulose nanocrystals (CNC), from microcrystalline cellulose (MCC), derived from Ayous sawdust. The process involves multiple steps and a large amount of chemical products. The objective of this research was to determine the effects of factors that impact the isolation process and to identify the optimal conditions for CNC isolation by using the response surface methodology. The factors that varied during the process were the quantity of MCC, the concentration of sulfuric acid, the hydrolysis time and temperature, and the ultrasonic treatment time. The response measured was the yield. The study found that with 5.80 g of microcrystalline cellulose, a sulfuric acid concentration of 63.50% (w/w), a hydrolysis time of 53 minutes, a hydrolysis temperature of 69˚C, and a sonication time of 19 minutes are the ideal conditions for isolation. The experimental yield achieved was (37.84 ± 0.99) %. The main factors influencing the process were the sulfuric acid concentration, hydrolysis time and temperature, with a significant influence (p < 0.05). Infrared characterization results showed that nanocrystals were indeed isolated. With a crystallinity of 35.23 and 79.74, respectively, for Ayous wood fiber and nanocrystalline cellulose were observed by X-ray diffraction, with the formation of type II cellulose, thermodynamically more stable than native cellulose type I. 展开更多
关键词 Ayous Sawdust Lignocellulosic Waste isolation Cellulose Nanocrystals OPTIMIZATION Response Surface Methodology
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Non-enzymatic methods for isolation of stromal vascular fraction and adipose-derived stem cells:A systematic review
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作者 Vamsi Krishna Mundluru MJ Naidu +4 位作者 Ravi Teja Mundluru Naveen Jeyaraman Sathish Muthu Swaminathan Ramasubramanian Madhan Jeyaraman 《World Journal of Methodology》 2024年第2期134-144,共11页
BACKGROUND Adipose-derived stem cells(ADSCs)and the stromal vascular fraction(SVF)have garnered substantial interest in regenerative medicine due to their potential to treat a wide range of conditions.Traditional enzy... BACKGROUND Adipose-derived stem cells(ADSCs)and the stromal vascular fraction(SVF)have garnered substantial interest in regenerative medicine due to their potential to treat a wide range of conditions.Traditional enzymatic methods for isolating these cells face challenges such as high costs,lengthy processing time,and regulatory complexities.AIM This systematic review aimed to assess the efficacy and practicality of nonenzymatic,mechanical methods for isolating SVF and ADSCs,comparing these to conventional enzymatic approaches.METHODS Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines,a comprehensive literature search was conducted across multiple databases.Studies were selected based on inclusion criteria focused on non-enzymatic isolation methods for SVF and ADSCs from adipose tissue.The risk of bias was assessed,and a qualitative synthesis of findings was performed due to the methodological heterogeneity of the included studies.RESULTS Nineteen studies met the inclusion criteria,highlighting various mechanical techniques such as centrifugation,vortexing,and ultrasonic cavitation.The review identified significant variability in cell yield and viability,and the integrity of isolated cells across different non-enzymatic methods compared to enzymatic procedures.Despite some advantages of mechanical methods,including reduced processing time and avoidance of enzymatic reagents,the evidence suggests a need for optimization to match the cell quality and therapeutic efficacy achievable with enzymatic isolation.CONCLUSION Non-enzymatic,mechanical methods offer a promising alternative to enzymatic isolation of SVF and ADSCs,potentially simplifying the isolation process and reducing regulatory hurdles.However,further research is necessary to standardize these techniques and ensure consistent,high-quality cell yields for clinical applications.The development of efficient,safe,and reproducible non-enzymatic isolation methods could significantly advance the field of regenerative medicine. 展开更多
关键词 Adipose-derived stem cells Stromal vascular fraction Regenerative medicine Non-enzymatic isolation Mechanical separation techniques
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Seismic Response Analysis of Steel Structure Isolation System Under Long-Period Seismic Motion
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作者 Long Yu Mei Sheng +1 位作者 Huan Feng Jianan Hu 《Journal of Architectural Research and Development》 2024年第3期147-155,共9页
To analyze the seismic response of steel structure isolation systems under long-period seismic motion,a 9-story steel frame building was selected as the subject.Five steel structure finite element models were establis... To analyze the seismic response of steel structure isolation systems under long-period seismic motion,a 9-story steel frame building was selected as the subject.Five steel structure finite element models were established using SAP2000.Response spectrum analysis was conducted on the seismic motion to determine if it adhered to the characteristics of long-period seismic motion.Modal analysis of each structural model revealed that the isolation structure significantly prolonged the structural natural vibration period and enhanced seismic performance.Base reactions and floor displacements of various structures notably increased under long-period seismic motion compared to regular seismic activity.Placing isolation bearings in the lower part of the structure proved more effective under long-period seismic motion.In seismic design engineering,it is essential to consider the impact of long-period seismic motion on structures and the potential failure of isolation bearings. 展开更多
关键词 Long-period seismic motion Steel structure Mid-story isolation structure isolation bearing Seismic performance
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Analysis of the Current Situation and Influencing Factors of Social Isolation Among the Elderly in the Community
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作者 Weiwei Dong Xiaohui Qi +3 位作者 Jialiang Wang Dongmei Cui Yanling Li Shaohua Li 《Proceedings of Anticancer Research》 2024年第3期150-156,共7页
Objective: To investigate the current situation of social isolation among the elderly in the community, and to analyze its influencing factors. Methods: A total of 265 elderly people were selected to conduct the surve... Objective: To investigate the current situation of social isolation among the elderly in the community, and to analyze its influencing factors. Methods: A total of 265 elderly people were selected to conduct the survey using the general information questionnaire and the Chinese version of the social isolation scale for the elderly. Results: The social isolation score of the elderly was (20.15 ± 0.23). Factors such as age, education level, economic status, and social participation ability influenced the social isolation score (P < 0.05). Conclusion: The social isolation of the elderly is more serious, and the social isolation can be alleviated by improving the level of education and the economic situation and strengthening social participation. 展开更多
关键词 COMMUNITY ELDERLY Social isolation
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The Relationship Between Social Isolation, Psychological Resilience, and Psychological Well- Being Among Older People in the Community
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作者 Lijing Wang Zhaoyu Bi +3 位作者 Hongying Tian Liping Xu Yanling Li Hongyun Cai 《Journal of Clinical and Nursing Research》 2024年第10期36-44,共9页
Objective:To explore the relationship between social isolation,psychological resilience,and psychological well-being in community-dwelling older adults.Methods:A questionnaire survey was conducted with 265 community-d... Objective:To explore the relationship between social isolation,psychological resilience,and psychological well-being in community-dwelling older adults.Methods:A questionnaire survey was conducted with 265 community-dwelling older adults using the Social Isolation Scale for the Elderly(C-SIS),the 10-item Brief Psychological Resilience Scale,and the Comprehensive Happiness Questionnaire(MHQ).The results were statistically analyzed using SPSS 27.0.Results:The highest score on the Social Isolation Scale for Community Elderly was 23,with a mean entry score of 2.36±0.62.A score of 14 was the cut-off point,with scores of≤14 classified as social isolation.There were 136 cases with scores below 14,resulting in a social isolation incidence rate of 51.3%.The median(P50)psychological resilience score was 27,indicating a higher level of resilience.The total score on the Psychological Well-being Scale was 161,suggesting a moderate to slightly higher level of well-being.Social isolation had a direct negative effect on psychological well-being,while psychological resilience had a positive effect.Conclusion:Older adults should be supported in reducing the incidence of social isolation and increasing psychological resilience to enhance psychological well-being and promote successful aging. 展开更多
关键词 COMMUNITY Older people Social isolation Psychological resilience Psychological well-being
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Optimizing the Isolation Forest Algorithm for Identifying Abnormal Behaviors of Students in Education Management Big Data
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作者 Bibo Feng Lingli Zhang 《Journal of Artificial Intelligence and Technology》 2024年第1期31-39,共9页
With the changes in educational models,applying computer algorithms and artificial intelligence technologies to data analysis in universities has become a research hotspot in the field of intelligent education.In resp... With the changes in educational models,applying computer algorithms and artificial intelligence technologies to data analysis in universities has become a research hotspot in the field of intelligent education.In response to the increasing amount of student data in universities,this study proposes to use an optimized isolated forest algorithm for recognizing features to detect abnormal student behavior concealed in big data for educational management.Firstly,it uses a logistic regression algorithm to update the calculation method of isolated forest weights and then uses residual statistics to eliminate redundant forests.Finally,it utilizes discrete particle swarm optimization to optimize the isolated forest algorithm.On this basis,improvements have also been made to the traditional gated loop unit network.It merges the two improved algorithm models and builds an anomaly detection model for collecting college student education data.The experiment shows that the optimized isolated forest algorithm has a recognition accuracy of 0.986 and a training time of 1s.The recognition accuracy of the improved gated loop unit network is 0.965,and the training time is 0.16s.In summary,the constructed model can effectively identify abnormal data of college students,thereby helping educators to detect students’problems in time and helping students to improve their learning status. 展开更多
关键词 isolated forest algorithm education abnormal behavior big data DISTINGUISH
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