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Pinning energies of organic semiconductors in high-efficiency organic solar cells 被引量:1
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作者 Xian’e Li Qilun Zhang +1 位作者 Xianjie Liu Mats Fahlman 《Journal of Semiconductors》 EI CAS CSCD 2023年第3期52-61,共10页
With the emergence of new materials for high-efficiency organic solar cells(OSCs),understanding and finetuning the interface energetics become increasingly important.Precise determination of the so-called pinning ener... With the emergence of new materials for high-efficiency organic solar cells(OSCs),understanding and finetuning the interface energetics become increasingly important.Precise determination of the so-called pinning energies,one of the critical characteristics of the material to predict the energy level alignment(ELA)at either electrode/organic or organic/organic interfaces,are urgently needed for the new materials.Here,pinning energies of a wide variety of newly developed donors and nonfullerene acceptors(NFAs)are measured through ultraviolet photoelectron spectroscopy.The positive pinning energies of the studied donors and the negative pinning energies of NFAs are in the same energy range of 4.3−4.6 eV,which follows the design rules developed for fullerene-based OSCs.The ELA for metal/organic and inorganic/organic interfaces follows the predicted behavior for all of the materials studied.For organic-organic heterojunctions where both the donor and the NFA feature strong intramolecular charge transfer,the pinning energies often underestimate the experimentally obtained interface vacuum level shift,which has consequences for OSC device performance. 展开更多
关键词 organic semiconductors organic solar cells pinning energies integer charge transfer interface dipoles
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Etiology matters:genetic and acquired prion diseases engage different mechanisms at a presymptomatic stage
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作者 Walker S.Jackson 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第12期2707-2708,共2页
One of the most enigmatic problems in biomedical research surrounds the phenomenon that neurodegenerative diseases target specific cell types and brain regions.This is difficult to explain because the proteins that ca... One of the most enigmatic problems in biomedical research surrounds the phenomenon that neurodegenerative diseases target specific cell types and brain regions.This is difficult to explain because the proteins that cause them are widely expressed,often highest in resistant regions.This mystery is further complicated by the fact that some disease-causing proteins are associated with multiple diseases. 展开更多
关键词 diseases DEGENERATIVE mechanisms
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Volatility spillovers,structural breaks and uncertainty in technology sector markets
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作者 Linn Arnell Emma Engström +2 位作者 Gazi Salah Uddin MdBokhtiar Hasan Sang Hoon Kang 《Financial Innovation》 2023年第1期2908-2938,共31页
This study uses the dynamic conditional correlation to investigate how technology subsector stocks interact with financial assets in the face of economic and financial uncertainty.Our results suggest that structural b... This study uses the dynamic conditional correlation to investigate how technology subsector stocks interact with financial assets in the face of economic and financial uncertainty.Our results suggest that structural breaks have diverse effects on financial asset connectedness and that the level of bond linkage increases when the trend breaks.We see a growing co-movement between the technology sector and major financial assets when uncertainty is considered.Overall,our findings indicate that the connectedness response varies depending on the type of uncertainty shock. 展开更多
关键词 Technology sector DIVERSIFICATION Dynamic conditional correlation UNCERTAINTY Structural breaks
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VGWO: Variant Grey Wolf Optimizer with High Accuracy and Low Time Complexity
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作者 Junqiang Jiang Zhifang Sun +3 位作者 Xiong Jiang Shengjie Jin Yinli Jiang Bo Fan 《Computers, Materials & Continua》 SCIE EI 2023年第11期1617-1644,共28页
The grey wolf optimizer(GWO)is a swarm-based intelligence optimization algorithm by simulating the steps of searching,encircling,and attacking prey in the process of wolf hunting.Along with its advantages of simple pr... The grey wolf optimizer(GWO)is a swarm-based intelligence optimization algorithm by simulating the steps of searching,encircling,and attacking prey in the process of wolf hunting.Along with its advantages of simple principle and few parameters setting,GWO bears drawbacks such as low solution accuracy and slow convergence speed.A few recent advanced GWOs are proposed to try to overcome these disadvantages.However,they are either difficult to apply to large-scale problems due to high time complexity or easily lead to early convergence.To solve the abovementioned issues,a high-accuracy variable grey wolf optimizer(VGWO)with low time complexity is proposed in this study.VGWO first uses the symmetrical wolf strategy to generate an initial population of individuals to lay the foundation for the global seek of the algorithm,and then inspired by the simulated annealing algorithm and the differential evolution algorithm,a mutation operation for generating a new mutant individual is performed on three wolves which are randomly selected in the current wolf individuals while after each iteration.A vectorized Manhattan distance calculation method is specifically designed to evaluate the probability of selecting the mutant individual based on its status in the current wolf population for the purpose of dynamically balancing global search and fast convergence capability of VGWO.A series of experiments are conducted on 19 benchmark functions from CEC2014 and CEC2020 and three real-world engineering cases.For 19 benchmark functions,VGWO’s optimization results place first in 80%of comparisons to the state-of-art GWOs and the CEC2020 competition winner.A further evaluation based on the Friedman test,VGWO also outperforms all other algorithms statistically in terms of robustness with a better average ranking value. 展开更多
关键词 Intelligence optimization algorithm grey wolf optimizer(GWO) manhattan distance symmetric coordinates
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Analysis of the SBP-SAT Stabilization for Finite Element Methods Part Ⅱ:Entropy Stability
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作者 R.Abgrall J.Nordström +1 位作者 P.Öffner S.Tokareva 《Communications on Applied Mathematics and Computation》 2023年第2期573-595,共23页
In the hyperbolic research community,there exists the strong belief that a continuous Galerkin scheme is notoriously unstable and additional stabilization terms have to be added to guarantee stability.In the first par... In the hyperbolic research community,there exists the strong belief that a continuous Galerkin scheme is notoriously unstable and additional stabilization terms have to be added to guarantee stability.In the first part of the series[6],the application of simultaneous approximation terms for linear problems is investigated where the boundary conditions are imposed weakly.By applying this technique,the authors demonstrate that a pure continu-ous Galerkin scheme is indeed linearly stable if the boundary conditions are imposed in the correct way.In this work,we extend this investigation to the nonlinear case and focus on entropy conservation.By switching to entropy variables,we provide an estimation of the boundary operators also for nonlinear problems,that guarantee conservation.In numerical simulations,we verify our theoretical analysis. 展开更多
关键词 Continuous Galerkin Entropy stability Simultaneous approximation terms Initial-boundary value problem Hyperbolic conservation laws
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Defect passivation by nontoxic biomaterial yields 21% efficiency perovskite solar cells 被引量:3
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作者 Shaobing Xiong Tianyu Hao +8 位作者 Yuyun Sun Jianming Yang Ruru Ma Jiulong Wang Shijing Gong Xianjie Liu Liming Ding Mats Fahlman Qinye Bao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第4期265-271,共7页
Defect passivation is one of the most important strategies to boost both the efficiency and stability of perovskite solar cells(PSCs).Here,nontoxic and sustainable forest-based biomaterial,betulin,is first introduced ... Defect passivation is one of the most important strategies to boost both the efficiency and stability of perovskite solar cells(PSCs).Here,nontoxic and sustainable forest-based biomaterial,betulin,is first introduced into perovskites.The experiments and calculations reveal that betulin can effectively passivate the uncoordinated lead ions in perovskites via sharing the lone pair electrons of hydroxyl group,promoting charge transport.As a result,the power conversion efficiencies of the p-i-n planar PSCs remarkably increase from 19.14%to 21.15%,with the improvement of other parameters.The hydrogen bonds of betulin lock methylamine and halogen ions along the grain boundaries and on the film surface and thus suppress ion migration,further stabilizing perovskite crystal structures.These positive effects enable the PSCs to maintain 90%of the initial efficiency after 30 days in ambient air with 60%±5%relative humidity,75%after 300 h aging at 85℃,and 55%after 250 h light soaking,respectively.This work opens a new pathway for using nontoxic and low-cost biomaterials from forest to make highly efficient and stable PSCs. 展开更多
关键词 Perovskite solar cells Defect passivation Nontoxic biomaterial EFFICIENCY
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An Update on the Efficacy and Functionality of Probiotics for the Treatment of Non-Alcoholic Fatty Liver Disease 被引量:2
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作者 Mingfei Yao Lingling Qv +3 位作者 Yanmeng Lu Baohong Wang Björn Berglund Lanjuan Li 《Engineering》 SCIE EI 2021年第5期679-686,共8页
Non-alcoholic fatty liver disease(NAFLD),which has a global prevalence of 20%–33%,has become the main cause of chronic liver disease.Except for lifestyle medication,no definitive medical treatment has been establishe... Non-alcoholic fatty liver disease(NAFLD),which has a global prevalence of 20%–33%,has become the main cause of chronic liver disease.Except for lifestyle medication,no definitive medical treatment has been established so far,making it urgent to find effective strategies for the treatment of NAFLD.With the identification of the significant role played by the gut microbiota in the pathogenesis of NAFLD,studies on probiotics for the prevention and treatment of NAFLD are increasing in number.Bacteria from the Bifidobacterium and Lactobacillus genera constitute the most widely used traditional probiotics.More recently,emerging next-generation probiotics(NGPs)such as Akkermansia muciniphila and Faecalibacterium prausnitzii have also gained attention due to their potential as therapeutic options for the treatment of NAFLD.This review provides an overview of the effects of oral administration of traditional probiotics and NGPs on the development and progress of NAFLD.The mechanisms by which probiotics directly or indirectly affect the disease are illustrated,based on the most recent animal and clinical studies.Although numerous studies have been published on this topic,further research is required to comprehensively understand the specific underlying mechanisms among probiotics,gut microbiota,and NAFLD,and additional large-scale clinical trials are required to evaluate the therapeutic efficacy of probiotics for the treatment of NAFLD,as well as the safety of probiotics in the human body. 展开更多
关键词 Non-alcoholic fatty liver disease(NAFLD) Gut microbiota PROBIOTICS Next-generation probiotics(NGPs)
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Association of gene and protein expression and genetic polymorphism of CC chemokine ligand 4 in colorectal cancer 被引量:2
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作者 Levar Shamoun Kalle Landerholm +3 位作者 Amanda Balboa Ramilo Roland E Andersson Jan Dimberg Dick Wågsäter 《World Journal of Gastroenterology》 SCIE CAS 2021年第30期5076-5087,共12页
BACKGROUND Leukocytes,such as T cells and macrophages,play an important role in tumorigenesis.CC chemokine ligand(CCL)4,which is produced by lymphocytes and macrophages,has been found to be expressed in the mucosa of ... BACKGROUND Leukocytes,such as T cells and macrophages,play an important role in tumorigenesis.CC chemokine ligand(CCL)4,which is produced by lymphocytes and macrophages,has been found to be expressed in the mucosa of the gastrointestinal tract and is a potent chemoattractant for various leukocytes.AIM To examine CCL4 expression and its genetic polymorphism rs10491121 in patients with colorectal cancer(CRC)and evaluate their prognostic significance.METHODS Luminex technology was used to determine CCL4 Levels in CRC tissue(n=98),compared with paired normal tissue,and in plasma from patients with CRC(n=103),compared with healthy controls(n=97).Included patients had undergone surgical resection for primary colorectal adenocarcinomas between 1996 and 2019 at the Department of Surgery,Ryhov County Hospital,Jönköping,Sweden.Reverse transcription quantitative PCR was used to investigate the CCL4 gene expression in CRC tissue(n=101).Paired normal tissue and TaqMan single nucleotide polymorphism assays were used for the CCL4 rs10491121 polymorphism in 610 CRC patients and 409 healthy controls.RESULTS The CCL4 protein and messenger RNA expression levels were higher in CRC tissue than in normal paired tissue(90%,P<0.001 and 45%,P<0.05,respectively).CRC tissue from patients with localized disease had 2.8-fold higher protein expression levels than that from patients with disseminated disease.Low CCL4 protein expression levels in CRC tissue were associated with a 30%lower cancer-specific survival rate in patients(P<0.01).The level of plasma CCL4 was 11%higher in CRC patients than in healthy controls(P<0.05)and was positively correlated(r=0.56,P<0.01)with the CCL4 protein level in CRC tissue.The analysis of CCL4 gene polymorphism rs10491121 showed a difference(P<0.05)between localized disease and disseminated disease in the right colon,with a dominance of allele A in localized disease.Moreover,the rate of the A allele was higher among CRC patients with mucinous cancer than among those with nonmucinous cancer.CONCLUSION The present study indicates that the CRC tissue levels of CCL4 and CCL4 gene polymorphism rs10491121,particularly in the right colon,are associated with clinical outcome in CRC patients. 展开更多
关键词 CC chemokine ligand 4 Gene polymorphism Gene and protein expression CHEMOKINE Survival rate Colorectal cancer
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Contrasting lipid biomarkers in mountain rivers in the Nepal Himalayas: Organic matter characteristics and contribution to the fluvial carbon pool 被引量:1
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作者 Rajendra Bhandari Joyanto Routh +1 位作者 Subodh Sharma Rajendra Joshi 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第6期1-15,共15页
The Nepal Himalayas is the source of many glacial and spring-fed river systems crisscrossing the mountainous terrain.There is an increasing recognition of small mountain rivers(SMRs)to have a significant combined expo... The Nepal Himalayas is the source of many glacial and spring-fed river systems crisscrossing the mountainous terrain.There is an increasing recognition of small mountain rivers(SMRs)to have a significant combined export of dissolved and particulate organic carbon to the global carbon flux.We analyzed fluvial sediments from two SMRs and compared the results with two large mountain rivers(LMRs)in Nepal.We investigated the organic matter(OM),its compositional variability,and seasonal export using a suite of lipid biomarkers,namely n-alkanes,n-alkanoic acids,n-alkanols,and sterols.The SMRs indicated a similarity in lipid distribution and were affected by a strong seasonal variability.The LMRs showed a distinct contrast in the distribution of lipids in suspended sediments.Bedload sediments in SMRs were derived from diverse sources with weak terrigenous dominance all-year-round compared to the suspended load.Functional lipids(n-alkanoic acids and n-alkanols)were the major constituents in SMR sediments,indicating better preservation.In contrast,n-alkane concentration dominated over other fractions in suspended sediments retrieved from LMRs.The biomarker trends differentiate SMRs from LMRs with lower transformed/degraded OM in SMRs.A common observation was the strong presence of even carbon compounds in short-chain n-alkanes in SMR bedload sediments and their predominance in suspended sediments in LMRs.Such an unusual trend is attributed to specific biomarker sources from the catchment and ongoing processes in fluvial systems.Topsoil colonized by fungal species under moist acidic conditions and autochthonous bacteria contributes to the organic matter pool in shallow SMRs.In LMRs,the contribution from thermally mature sedimentary hydrocarbons and the diagenetic reduction of nalkanoic acids to n-alkanes are additional contributors to the allochthonous carbon pool.The differences in lipid concentrations,their distribution,seasonality,and the size of rivers suggest differential preservation/degradation of the organic matter pool and their importance in contributing to the carbon budget. 展开更多
关键词 Fluvial sediments BEDLOAD Suspended load MONSOON Biomarkers BIOGEOCHEMISTRY
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Oxytocin in pig seminal plasma is positively related with in vivo fertility of inseminated sows 被引量:1
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作者 Lorena Padilla Marina López-Arjona +3 位作者 Silvia Martinez-Subiela Heriberto Rodriguez-Martinez Jordi Roca Isabel Barranco 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2022年第2期430-440,共11页
Background:Identification of relevant in vivo biomarkers for fertility remains a challenge for the livestock industry.Concentrations of the small peptide hormone oxytocin(OXT),involved in male reproductive function an... Background:Identification of relevant in vivo biomarkers for fertility remains a challenge for the livestock industry.Concentrations of the small peptide hormone oxytocin(OXT),involved in male reproductive function and present in the seminal plasma(SP)of several species could be a robust one.This study characterized concentrations of SPOXT in ejaculates from boars used in artificial insemination(AI)programs aiming to evaluate its relationship with sperm quality variables and in vivo fertility of their liquid-stored AI-semen.Seminal OXT concentrations(ng/mL)were measured in 169 ejaculates from 61 boars of the Duroc,Pietrain,Landrace and Large White breeds using a direct competitive immunoassay test based on AlphaLISA®technology.Ejaculate(ejaculate volume,sperm concentration,total sperm count)and sperm parameters(motility,viability,intracellular generation of reactive oxygen species,plasma membrane fluidity)were assessed at 0 h and 72 h in AI-semen samples stored at 17℃.In vivo fertility included only 18 Large White and Landrace boars whose AI-semen was used to inseminated>100 sows and evaluated both farrowing rate and litter size of 3,167 sows.Results:The results showed that SP-OXT differed between boars and between ejaculates within boar(P<0.05)but not between breeds(Duroc,Pietrain,Landrace and Large White).Ejaculates with higher SP-OXT concentration/mL(hierarchically grouped;P<0.001)had larger volume and came from younger boars(P<0.05).Ejaculates of boars showing positive farrowing rate deviation exhibited higher(P<0.05)SP-OXT concentration/mL than those with negative farrowing rate deviation.Conclusion:The SP concentrations of OXT are boar,ejaculate and age dependent,and positively related with ejaculate volume and farrowing rates of liquid-stored semen AI-doses. 展开更多
关键词 Artificial insemination EJACULATE FERTILITY OXYTOCIN PIG Semen quality Seminal plasma
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Electrochemical Lithium Storage Performance of Molten Salt Derived V_(2)SnC MAX Phase 被引量:2
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作者 Youbing Li Guoliang Ma +18 位作者 Hui Shao Peng Xiao Jun Lu Jin Xu Jinrong Hou Ke Chen Xiao Zhang Mian Li Per OÅPersson Lars Hultman Per Eklund Shiyu Du Zhifang Chai Zhengren Huang Na Jin Jiwei Ma Ying Liu Zifeng Lin Qing Huang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第10期266-275,共10页
MAX phases are gaining attention as precursors of two-dimensional MXenes that are intensively pursued in applications for electrochemical energy storage.Here,we report the preparation of V_(2)SnC MAX phase by the molt... MAX phases are gaining attention as precursors of two-dimensional MXenes that are intensively pursued in applications for electrochemical energy storage.Here,we report the preparation of V_(2)SnC MAX phase by the molten salt method.V_(2)SnC is investigated as a lithium storage anode,showing a high gravimetric capacity of 490 mAh g−1 and volumetric capacity of 570 mAh cm^(−3) as well as superior rate performance of 95 mAh g^(−1)(110 mAh cm^(−3))at 50 C,surpassing the ever-reported performance of MAX phase anodes.Sup-ported by operando X-ray diffraction and density functional theory,a charge storage mechanism with dual redox reaction is proposed with a Sn-Li(de)alloying reaction that occurs at the edge sites of V_(2)SnC particles where Sn atoms are exposed to the electrolyte followed by a redox reaction that occurs at V_(2)C layers with Li.This study offers promise of using MAX phases with M-site and A-site elements that are redox active as high-rate lithium storage materials. 展开更多
关键词 MAX phase Molten salt Lithium storage High-rate Energy storage
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Ionic thermoelectric materials and devices 被引量:1
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作者 Dan Zhao Alois Würger Xavier Crispin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第10期88-103,I0003,共17页
The tremendous amount of wasted heat from solar radiation and industry dissipation has motivated the development of thermoelectric concepts that directly convert heat into electricity.The main challenge in practical a... The tremendous amount of wasted heat from solar radiation and industry dissipation has motivated the development of thermoelectric concepts that directly convert heat into electricity.The main challenge in practical applications for thermoelectrics is the high cost from both materials and manufacturing.Recently,breakthrough progresses in ionic thermoelectrics open up new possibilities to charge energy storage devices when submitted to a temperature gradient.The charging voltage is internally from the ionic Seebeck effect of the electrolyte between two electrodes.Hence electrolytes with high thermoelectric figure of merit are classified as ionic thermoelectric materials.Most ionic thermoelectric materials are composed of abundant elements,and they can generate hundreds of times larger thermal voltage than that of electronic materials.This emerging thermoelectric category brings new hope to fabricate low cost and large area heat-to-energy conversion devices,and triggers a renewed interest for ionic thermodiffusion.In this review,we summarize the state of the art in the new field of ionic thermoelectrics,from the driving force of the ionic thermodiffusion to material and application developments.We present a general map of ionic thermoelectric materials,discuss the unique characters of each type of the reported electrolytes,and propose potential optimization and future topics of ionic thermoelectrics. 展开更多
关键词 Electrolytes Soret effect THERMODIFFUSION Thermal energy conversion
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Al/Mo-C中间层对锆合金表面Zr_(2)Al_(3)C_(4)涂层界面性能影响
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作者 叶文浩 魏强 +4 位作者 梁佳敏 周洁 孟凡平 EKLUND Per 黄庆 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2021年第5期541-546,共6页
锆合金表面涂层研究作为提高核燃料包壳事故容错能力的重要技术手段之一,能够有效解决失水事故下锆水反应的问题。Zr_(2)Al_(3)C_(4)以其优异的抗氧化性能和适用于核环境的化学组分而成为锆合金包壳的候选涂层材料之一。由于Zr_(2)Al_(3... 锆合金表面涂层研究作为提高核燃料包壳事故容错能力的重要技术手段之一,能够有效解决失水事故下锆水反应的问题。Zr_(2)Al_(3)C_(4)以其优异的抗氧化性能和适用于核环境的化学组分而成为锆合金包壳的候选涂层材料之一。由于Zr_(2)Al_(3)C_(4)涂层与锆合金基底之间的元素扩散以及热膨胀系数不匹配等问题,在其上制备Zr_(2)Al_(3)C_(4)涂层的相关研究较少。本研究通过磁控溅射结合后续热处理工艺,以Al/Mo-C作为扩散屏障层,在锆合金基底上制备Zr_(2)Al_(3)C_(4)涂层。结合X射线衍射仪、扫描电子显微镜和透射电子显微镜等分析手段,研究了Al/Mo-C中间层对涂层的相和微观结构的影响。结果表明,在800℃退火3 h后,未添加中间层的涂层开裂,同时由于Zr-Al-C涂层与基底之间存在明显的元素扩散,导致Zr_(2)Al_(3)C_(4)无法成相。Al/Mo-C中间层作为扩散屏障,能够有效阻止退火过程中Zr-Al-C涂层和基底之间的元素扩散,从而大大降低Zr-Al-C涂层与标准化学量比的偏差,有利于最终涂层中Zr_(2)Al_(3)C_(4)相的形成。此外,该扩散屏障层能够抑制Zr_(2)Al_(3)C_(4)涂层在退火过程中产生裂纹,同时将退火态涂层与锆合金基底的结合力提高30 N。 展开更多
关键词 Zr_(2)Al_(3)C_(4) 中间层 扩散屏障 结合力
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Lumbar interspinous pressure pain threshold values for healthy young men and women and the effect of prolonged fully flexed lumbar sitting posture:An observational study 被引量:2
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作者 Martin Petersson Allan Abbott 《World Journal of Orthopedics》 2020年第3期158-166,共9页
BACKGROUND Low back pain(LBP)is a common condition with large burden worldwide.Exposure to prolonged sitting with a flexed lumbar posture has been suggested in the literature to be a potential risk factor for self-rep... BACKGROUND Low back pain(LBP)is a common condition with large burden worldwide.Exposure to prolonged sitting with a flexed lumbar posture has been suggested in the literature to be a potential risk factor for self-reported LBP.No study has previously investigated whether exposure to prolonged flexed sitting posture provokes discomfort/pain and decreased interspinous pressure pain thresholds for healthy young men and women without back pain,despite this being a suggested risk factor for LBP.AIM To investigate whether sitting in a prolonged flexed lumbar posture provokes discomfort and lowers interspinous pressure pain thresholds in the lumbar spine for healthy young men and women without previous LBP.METHODS This is a an observational before and after study of 26 participants(13 men,13 women)between 20-35 years old.Algometry was used to examine the pain threshold for pressure applied between spinous processes of the lumbar spine L1-L5.Pressure algometer measures were performed in prone before and after participants were instructed to sit in a fully flexed posture for a maximum of 15 min or until discomfort was experienced in the low back(Borg CR10=7/10).Wilcoxon signed-rank test was used for analyze values from the before and after test conditions.Mann-Whitney U test was used to investigate potential gender difference.RESULTS Fully flexed lumbar spine sitting posture up to 15 min provoked temporary discomfort but the proportion of participants experiencing discomfort 7/10 in the low back was 62%.For all pain pressure threshold locations tested,there was a significant difference for the study population with moderate-large decreased(r=-0.56)pressure pain threshold after exposure to prolonged flexed sitting posture(P<0.01).Comparisons between gender did not show any significant difference.CONCLUSION The result showed that exposure to fully flexed lumbar sitting posture for up to 15 min produced temporary discomfort in the low back in young healthy adults with no previous history of LBP and significantly reduced lumbar interspinous pressure pain thresholds.No gender-based differences were observed. 展开更多
关键词 Low back pain Pain pressure threshold Algometer POSTURE SPINE Pain mechanism
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Roles of cell fusion, hybridization and polyploid cell formation in cancer metastasis 被引量:1
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作者 Ivan Shabo Joar Svanvik +5 位作者 Annelie Lindström Tanguy Lechertier Sara Trabulo James Hulit Tim Sparey John Pawelek 《World Journal of Clinical Oncology》 2020年第3期121-135,共15页
Cell-cell fusion is a normal biological process playing essential roles in organ formation and tissue differentiation,repair and regeneration.Through cell fusion somatic cells undergo rapid nuclear reprogramming and e... Cell-cell fusion is a normal biological process playing essential roles in organ formation and tissue differentiation,repair and regeneration.Through cell fusion somatic cells undergo rapid nuclear reprogramming and epigenetic modifications to form hybrid cells with new genetic and phenotypic properties at a rate exceeding that achievable by random mutations.Factors that stimulate cell fusion are inflammation and hypoxia.Fusion of cancer cells with non-neoplastic cells facilitates several malignancy-related cell phenotypes,e.g.,reprogramming of somatic cell into induced pluripotent stem cells and epithelial to mesenchymal transition.There is now considerable in vitro,in vivo and clinical evidence that fusion of cancer cells with motile leucocytes such as macrophages plays a major role in cancer metastasis.Of the many changes in cancer cells after hybridizing with leucocytes,it is notable that hybrids acquire resistance to chemo-and radiation therapy.One phenomenon that has been largely overlooked yet plays a role in these processes is polyploidization.Regardless of the mechanism of polyploid cell formation,it happens in response to genotoxic stresses and enhances a cancer cell’s ability to survive.Here we summarize the recent progress in research of cell fusion and with a focus on an important role for polyploid cells in cancer metastasis.In addition,we discuss the clinical evidence and the importance of cell fusion and polyploidization in solid tumors. 展开更多
关键词 Cell fusion Hybrid formation POLYPLOIDIZATION MACROPHAGE Cancer progression Oncologic treatment resistance
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Magnetotactic bacteria from the human gut microbiome associated with orientation and navigation regions of the brain
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作者 Rozalyn A.SIMON Purnika Damindi RANASINGHE +8 位作者 Nawroz BARAZANJI Malin Bergman JUNGESTRÖM Jie XU Olga BEDNARSKA Lena SERRANDER Maria ENGSTRÖM Dennis A.BAZYLINSKI Åsa V.KEITA Susanna WALTER 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第6期2044-2052,共9页
Magnetotactic bacteria(MTB),ubiquitous in soil and fresh and saltwater sources have been identified in the microbiome of humans and many animals.MTB endogenously produce magnetic nanocrystals enabling them to orient a... Magnetotactic bacteria(MTB),ubiquitous in soil and fresh and saltwater sources have been identified in the microbiome of humans and many animals.MTB endogenously produce magnetic nanocrystals enabling them to orient and navigate along geomagnetic fields.Similar magnetite deposits have been found throughout the tissues of the human brain,including brain regions associated with orientation such as the cerebellum and hippocampus,the origins of which remain unknown.Speculation over the role and source of MTB in humans,as well as any association with the brain,remain unanswered.We performed a metagenomic analysis of the gut microbiome of 34 healthy females as well as grey matter volume analysis in magnetite-rich brain regions associated with orientation and navigation with the goal of identifying specific MTB that could be associated with brain structure in orientation and navigation regions.We identified seven MTB in the human gut microbiome:Magnetococcus marinus,Magnetospira sp.QH-2,Magnetospirillum magneticum,Magnetospirillum sp.ME-1,Magnetospirillum sp.XM-1,Magnetospirillum gryphiswaldense,and Desulfovibrio magneticus.Our preliminary results show significant negative associations between multiple MTB with bilateral flocculonodular lobes of the cerebellum and hippocampus(adjusted for total intracranial volume,uncorrected P<0.05).These findings indicate that MTB in the gut are associated with grey matter volume in magnetite-rich brain regions related to orientation and navigation.These preliminary findings support MTB as a potential biogenic source for brain magnetite in humans.Further studies will be necessary to validate and elucidate the relationship between these bacteria,magnetite concentrations,and brain function. 展开更多
关键词 magnetotactic bacteria human microbiome microbiota-gut-brain axis MAGNETORECEPTION
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Histidine decarboxylase and urinary methylimidazoleacetic acid in gastric neuroendocrine cells and tumours
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作者 Apostolos V Tsolakis Lars Grimelius +3 位作者 Göran Granerus Mats Stridsberg Sture E Falkmer Eva T Janson 《World Journal of Gastroenterology》 SCIE CAS 2015年第47期13240-13249,共10页
AIM: To study histidine decarboxylase(HDC) expression in normal and neoplastic gastric neuroendocrine cells in relationship to the main histamine metabolite. METHODS: Control tissues from fundus(n = 3) and corpus(n = ... AIM: To study histidine decarboxylase(HDC) expression in normal and neoplastic gastric neuroendocrine cells in relationship to the main histamine metabolite. METHODS: Control tissues from fundus(n = 3) and corpus(n = 3) mucosa of six patients undergoing operations for gastric adenocarcinoma, biopsy and/or gastric surgical specimens from 64 patients with primary gastric neuroendocrine tumours(GNETs), as well as metastases from 22 of these patients, were investigated using conventional immunohistochemistry and double immunofluorescence with commercial antibodies vs vesicular monoamine transporter 2(VMAT-2), HDC and ghrelin. The urinary excretion of the main histamine metabolite methylimidazoleacetic acid(U-Me Im AA) was determined using highperformance liquid chromatography in 27 of the 64 patients.RESULTS: In the gastric mucosa of the control tissues, co-localization studies identified neuroendocrine cells that showed immunoreactivity only to VMAT-2 and others with reactivity only to HDC. A third cellpopulation co-expressed both antigens. There was no co-expression of HDC and ghrelin. Similar results were obtained in the foci of neuroendocrine cell hyperplasia associated with chronic atrophic gastritis type A and also in the tumours. The relative incidence of the three aforementioned markers varied in the tumours that were examined using conventional immunohistochemistry. All of these GNETs revealed both VMAT-2 and HDC immunoreactivity, and their metastases showed an immunohistochemical pattern and frequency similar to that of their primary tumours. In four patients, increased U-Me Im AA excretion was detected, but only two of the patients exhibited related endocrine symptoms. CONCLUSION: Human enterochromaffin-like cells appear to partially co-express VMAT-2 and HDC. Coexpression of VMAT-2 and HDC might be required for increased histamine production in patients with GNETs. 展开更多
关键词 Enterochromaffin-like cells High performance liquid chromatography Gastric neuroendocrine tumours Histidine decarboxylase Immunohistochemistry Urinary excretion of the main histamine metabolite methylimidazoleacetic acid Vesicular monoamine transporter 2
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A system for underground road condition monitoring
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作者 Max Astrand Erik Jakobsson +1 位作者 Martin Lindfors John Svensson 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第3期405-411,共7页
Poor road conditions in underground mine tunnels can lead to decreased production efficiency and increased wear on production vehicles. A prototype system for road condition monitoring is presented in this paper to co... Poor road conditions in underground mine tunnels can lead to decreased production efficiency and increased wear on production vehicles. A prototype system for road condition monitoring is presented in this paper to counteract this. The system consists of three components i.e. localization, road monitoring, and scheduling. The localization of vehicles is performed using a Rao-Blackwellized extended particle filter, combining vehicle mounted sensors with signal strengths of Wi Fi access points. Two methods for road monitoring are described: a Kalman filter used together with a model of the vehicle suspension system, and a relative condition measure based on the power spectral density. Lastly, a method for taking automatic action on an ill-conditioned road segment is proposed in the form of a rescheduling algorithm.The scheduling algorithm is based on the large neighborhood search and is used to integrate road service activities in the short-term production schedule while minimizing introduced production disturbances.The system is demonstrated on experimental data collected in a Swedish underground mine. 展开更多
关键词 LOCALIZATION Road condition monitoring SCHEDULING Underground mining
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Real-world evaluation of upfront docetaxel in metastatic castrationsensitive prostate cancer
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作者 Jenny Isaksson Henrik Green +5 位作者 Dimitrios Papantoniou Linn Pettersson Mats Anden Johan Rosell Elisabeth Åvall-Lundqvist Nils Oskar Elander 《World Journal of Clinical Oncology》 CAS 2021年第11期1009-1022,共14页
BACKGROUND The majority of patients with newly diagnosed metastatic prostate cancer(PC)initially respond to androgen deprivation therapy(ADT)and are classified as metastatic castration-sensitive PC(mCSPC).Following mo... BACKGROUND The majority of patients with newly diagnosed metastatic prostate cancer(PC)initially respond to androgen deprivation therapy(ADT)and are classified as metastatic castration-sensitive PC(mCSPC).Following months to years of ADT,the disease tends to become resistant to ADT.Recent randomized phase-III trials demonstrated a survival benefit with the addition of upfront docetaxel to ADT in mCSPC.Following its implementation in routine care,this combined treatment strategy requires more detailed evaluation in a real-world setting.AIM To assess the real-world outcome and safety of upfront docetaxel treatment in mCSPC.METHODS A multicenter retrospective cohort study in the Southeast Health Care Region of Sweden was performed.This region includes approximately 1.1 million citizens and the oncology departments of Linköping,Jönköping,and Kalmar.All patients given upfront docetaxel for mCSPC from July 2015 until December 2017 were included.The primary endpoint was progression-free survival(PFS)at 12 mo,and the secondary endpoints were PFS at 24 mo,overall survival(OS),treatment intensity,adverse events,and unplanned hospitalizations.Exploratory analyses on potential prognostic parameters were performed.RESULTS Ninety-four patients were eligible and formed the study cohort.PFS at 12 and 24 mo was 75%(95%CI:66–84)and 58%(46–70),respectively.OS at 12 and 24 mo was 93%(87–99)and 86%(76–96).A total of 91%of patients(n=86)were given docetaxel according to the standard protocol of 75 mg/m2 every 3 wk(6 cycles),while 9%(n=8)received a modified protocol of 50 mg/m2 every 2 wk(9 cycles).The average overall dose intensity for those commencing standard treatment was 91%.Univariate Cox regression analyses show that baseline PSA>180 vs<180 and the presence of distant metastases vs locoregional lymph node metastases were only negative prognostic factors(HR 2.86,95%CI:1.39–5.87,P=0.0041 and 3.36,95%CI:1.03–10.96,P=0.045).Following multivariate analysis,statistical significance remained for PSA(2.51,95%CI:1.21–5.19,P=0.013)but not for metastatic status(2.60,95%CI:0.78–8.65,P=0.12).Febrile neutropenia was recorded in 21%(n=20)of patients,and 26%(n=24)had at least one episode of unplanned hospitalization under and up to 30 d after the treatment course.CONCLUSION Results from this study support the implementation of upfront docetaxel plus ADT as part of the standard of care treatment strategy in mCSPC. 展开更多
关键词 Prostate cancer CHEMOTHERAPY DOCETAXEL Castration sensitive METASTATIC Real world
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Effects of diabetes type 2 and metformin treatment in Swedish patients with colorectal cancer
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作者 Jan Dimberg Levar Shamoun +1 位作者 Kalle Landerholm Dick Wågsäter 《World Journal of Gastroenterology》 SCIE CAS 2022年第19期2148-2151,共4页
The association between type 2 diabetes mellitus(DM)and colorectal cancer(CRC)has been thoroughly investigated and reports have demonstrated that the risk of CRC is increased in DM patients.The association between DM ... The association between type 2 diabetes mellitus(DM)and colorectal cancer(CRC)has been thoroughly investigated and reports have demonstrated that the risk of CRC is increased in DM patients.The association between DM and the survival of patients with CRC is controversial.Evidence suggests that metformin with its anti-inflammatory effects is a protective factor against the development of CRC among DM patients and that metformin therapy is associated with a better prognosis in patients with DM.In our cohort,we did not find any associations between the presence of DM or metformin and cancer specific survival or any relation to plasma levels of a panel of 40 inflammatory factors and irisin.On the other hand,we identified that the insulin-like growth factor binding protein 7 single nucleotide polymorphism rs2041437 was associated with DM in CRC patients.The dominance of the T bearing genotypes in patients with DM was statistically significant(P=0.038),with an odds ratio of 1.66(95%confidence interval:1.03-2.69). 展开更多
关键词 DIABETES METFORMIN CYTOKINES Survival Colorectal cancer POLYMORPHISM
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