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Systematic rationalization approach for multivariate correlated alarms based on interpretive structural modeling and Likert scale 被引量:5
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作者 高慧慧 徐圆 +2 位作者 顾祥柏 林晓勇 朱群雄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1987-1996,共10页
Alarm flood is one of the main problems in the alarm systems of industrial process. Alarm root-cause analysis and alarm prioritization are good for alarm flood reduction. This paper proposes a systematic rationalizati... Alarm flood is one of the main problems in the alarm systems of industrial process. Alarm root-cause analysis and alarm prioritization are good for alarm flood reduction. This paper proposes a systematic rationalization method for multivariate correlated alarms to realize the root cause analysis and alarm prioritization. An information fusion based interpretive structural model is constructed according to the data-driven partial correlation coefficient calculation and process knowledge modification. This hierarchical multi-layer model is helpful in abnormality propagation path identification and root-cause analysis. Revised Likert scale method is adopted to determine the alarm priority and reduce the blindness of alarm handling. As a case study, the Tennessee Eastman process is utilized to show the effectiveness and validity of proposed approach. Alarm system performance comparison shows that our rationalization methodology can reduce the alarm flood to some extent and improve the performance. 展开更多
关键词 Alarm rationalization Root-cause analysis Alarm priority Interpretive structural modeling Likert scale Tennessee Eastman process
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A Rationalization of Sympathetic Nucleation-Ledgewise Growth Theory of Bainite Transformation in Fe-C Alloys 被引量:1
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作者 Zhigang YANG, Chi ZHANG, Hongsheng FANG, Jinbo YANG, Bingzhe BAI and Jiajun WANG Department of Materials Science and Engineering, Tsinghua University Beijing 100084, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第4期433-438,共6页
Based on the classic diffusion controlled nucleation and goth theory, the sympathatic nucleation- ledgewise growth mechanism of bainite was studied theoretically for low carbon Fe-C alloys. The rationality of the occu... Based on the classic diffusion controlled nucleation and goth theory, the sympathatic nucleation- ledgewise growth mechanism of bainite was studied theoretically for low carbon Fe-C alloys. The rationality of the occurrence of sympathetic nucleation on the terraces of ledges compating with lateral ledge growth and other sites nucleation was demonstrated by the present work quantita- tively The calculations indicated that low reaction temperatures and high carbon concentrations may favor the sympathetic nucleation, thus accounting for the formation of multilayer structures of bainite. 展开更多
关键词 A rationalization of Sympathetic Nucleation-Ledgewise Growth Theory of Bainite Transformation in Fe-C Alloys FE
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The Threshold Effect of Rationalization of Industrial Structure on Air Quality in Shanxi Province 被引量:5
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作者 ZHU Meifeng WU Qinglong +1 位作者 ZHANG Huaming CHEN Zhanbo 《Journal of Resources and Ecology》 CSCD 2020年第2期206-212,共7页
Shanxi Province is a typical resource-based region. After years of economic transformation, the air quality has been at a low level for a long time. The rationalization of industrial structure can measure the effect o... Shanxi Province is a typical resource-based region. After years of economic transformation, the air quality has been at a low level for a long time. The rationalization of industrial structure can measure the effect of economic transformation and whether it has an important impact on air quality. Therefore, it is necessary to study the non-linear impact that the rationalization of industrial structure has had on air quality at different stages, which is of positive significance for the continuing transformation and upgrading of resource-based regions. This study constructs a threshold regression model based on the panel data of 11 provincial cities in Shanxi Province from 2004 to 2016. The results show that the rationalization of industrial structure had a double threshold effect on air quality under different threshold variables. On the whole, optimizing the rationalization of industrial structure in Shanxi Province can improve air quality, and the improvement effect dropped first, and then began to rise. As a result, the current energy transformation and upgrading process should focus on the rationalization of industrial structure to solve the conflict between air quality and economic development. 展开更多
关键词 rationalization of industrial structure air quality threshold effect Shanxi Province
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Study on the Measurement of Industrial Structure “Sophistication,Rationalization and Ecologicalization” Based on the Dynamic Analysis of Grey Relations——A Case Study of Beijing-Tianjin-Hebei 被引量:4
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作者 Shiyi YUAN Xiaopeng SUN +1 位作者 Weiguo CHEN Yongwu LI 《Journal of Systems Science and Information》 CSCD 2020年第2期130-147,共18页
The Beijing-Tianjin-Hebei region is one of the regions with the most dynamic economies,highest degrees of openness,strongest innovation capacities and largest populations,as well as an important engine driving China’... The Beijing-Tianjin-Hebei region is one of the regions with the most dynamic economies,highest degrees of openness,strongest innovation capacities and largest populations,as well as an important engine driving China’s economic development.Currently,the development of the BeijingTianjin-Hebei region faces many difficulties,including an inefficient distribution of regional functions,imbalance in industrial structure,low sophistication,and serious overburdening of resources and the environment.Promoting the overall coordinated development of the region has become an urgent challenge.In this paper,according to the conventions of industrial structure optimization,the three core indicators of regional industrial structure rationalization,sophistication and ecologicalization are constructed.With the help of the grey dynamic correlation model,the three indicators are coupled with the economic growth rate,and the industrial structure optimization index of the Beijing-Tianjin-Hebei region is comprehensively measured.The study shows that rationalization of the industrial structure in the Beijing-Tianjin-Hebei region is increasing but that this trend is not obvious;sophistication of the industrial structure is relatively high and has also been operating at a high level;however,the overall ecological level of the industrial structure in the Beijing-Tianjin-Hebei region is not high and presents the characteristics of high in the middle and low at both ends.In terms of the relationship between industrial structure and economic growth in the Beijing-Tianjin-Hebei region,ecologicalization of the industrial structure has the greatest influence on economic growth,followed by sophistication of the industrial structure,and rationalization of the industrial structure has the weakest influence. 展开更多
关键词 ecologicalization GREY dynamic analysis DEGREES INDUSTRIAL structure sophistication rationalization
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Rationalization and Mechanisms of Pulsed Laser Deposition of Fibroin Nanofilms by Using Autogenous Binder
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作者 S.Nakayama R.Nozaki M.Senna 《复旦学报(自然科学版)》 CAS CSCD 北大核心 2007年第5期853-,共1页
1 Results Homogeneity of fibroin thin films by pulsed laser deposition (PLD) was significantly improved by introducing autogenous binders to consolidate and homogenize the irradiation targets.Homogenization includes a... 1 Results Homogeneity of fibroin thin films by pulsed laser deposition (PLD) was significantly improved by introducing autogenous binders to consolidate and homogenize the irradiation targets.Homogenization includes among others,decreases in the size of nanostructural units and the fractional debris.Simultaneously,the deposition rate was substantially increased.Autogenous binders are prepared via degumming and liquefaction of fibroin by using Na2CO3 and LiBr,respectively.We also found that optically hom... 展开更多
关键词 rationalization pulsed laser deposition fibroin nanofilm
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The surface binding and energy issues in the rational design of separators for Li||S batteries
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作者 Hongfang Du Lijing Wang +8 位作者 Shuyu Cheng Chao Wu Sheng Yang Yang Liu Yi Zhao Dandan Cui Shaowei Zhang Shixue Dou Liangxu Lin 《Journal of Energy Chemistry》 2026年第1期987-1013,I0021,共28页
Lithium-sulfur batteries(LSBs)represent a next-generation energy storage technology,but widespread applications are restricted by the shuttle of lithium polysulfides(LiPSs).The rational design of separators has been d... Lithium-sulfur batteries(LSBs)represent a next-generation energy storage technology,but widespread applications are restricted by the shuttle of lithium polysulfides(LiPSs).The rational design of separators has been demonstrated to be one of the most efficient and cost-effective strategies to curb the shuttle effect,and tremendous research progress has been achieved.The efficiency of a separator depends on its interaction with LiPSs,which is governed by the surface energy and binding strength.Despite several review works that have been reported to advance the separators,most of them primarily focus on active material innovation and construction.The most crucial issues of surface binding energy have not been systematically reviewed,limiting the precise design of efficient separators.In this review,fundamentals related to surface energy and binding interactions with LiPSs are comprehensively analyzed and discussed.With surface binding and energy main lines,the advancements in separator engineering strategies are elaborately summarized and discussed.Moreover,techniques for evaluating affinity to LiPSs are thoroughly analyzed to avoid any ambiguities in measurement.Based on the research context,valuable research directions are suggested to construct efficient separators.This work provides guidelines to regulate the surface binding and energy of separators for high-performance LSBs. 展开更多
关键词 Lithium-sulfur batteries SEPARATOR Surface binding affinity Surface energy Rational design
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Pursuing Emotional Value
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《ChinAfrica》 2026年第3期60-61,共2页
The Double Take column looks at a single topic from an African and Chinese perspective.This month,we discuss how to understand the growing emphasis on emotional returns among young people.Emotional value has emerged a... The Double Take column looks at a single topic from an African and Chinese perspective.This month,we discuss how to understand the growing emphasis on emotional returns among young people.Emotional value has emerged as a central force shaping youth decision-making across work,consumption,relationships and lifestyle choices.Unlike traditional economic rationality that prioritises income and material security,emotional value focuses on how choices make individuals feel and how they align with personal meaning.This shift is particularly evident in rapidly transforming societies such as China and Ghana,where economic restructuring,globalisation and social change have reshaped pathways to adulthood. 展开更多
关键词 youth decision making emotional returns emotional value material security INCOME WORK CONSUMPTION economic rationality
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Optimizing carotenoid cleavage dioxygenase 4(CCD4)for enhancedβ-ionone production in Nicotiana tabacum
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作者 Chen Dong Yu Zhang +7 位作者 Zifu Ni Mengxin Shen Faming Lin Xiaoran Wang Yongchun Shi Yuchen Miao Jinggong Guo Ran Wang 《The Crop Journal》 2026年第1期214-223,共10页
Carotenoid cleavage dioxygenase 4(CCD4)controls the rate-limiting step ofβ-ionone biosynthesis,making it a valuable target for healthcare and pharmaceutical applications.Nicotiana tabacum,a carotenoid-richd crop spec... Carotenoid cleavage dioxygenase 4(CCD4)controls the rate-limiting step ofβ-ionone biosynthesis,making it a valuable target for healthcare and pharmaceutical applications.Nicotiana tabacum,a carotenoid-richd crop species,is a promising source forβ-ionone production.This study aimed to modify CCD4 activity to increaseβ-ionone yield in tobacco.We identified two isoforms of CCD4 in N.tabacum,NtCCD4a and NtCCD4b,with NtCCD4a exhibiting significantly higher expression levels than NtCCD4b.Using solid-phase microextraction gas chromatography-mass spectrometry(SPME-GC–MS),we demonstrated that NtCCD4a effectively catalyzes the cleavage ofβ-carotene to produceβ-ionone.To improve its enzymatic activity,we applied structure-based rational design to reconstruct the active pocket of NtCCD4a,followed by high-throughput screening of mutant variants.Three single base mutants,F181G,F184L,and F337M,in NtCCD4a showed enhancedβ-ionone production compared to the wild-type,with F337M yielding the highest amount.No synergistic effects were observed among the three mutants.Transgenic tobacco plants expressing the F181G,F184L,and F337M mutations had acceleratedβ-carotene cleavage and increasedβ-ionone production relative to the wild-type NtCCD4a.Our results establish a framework for the design of CCD4 in major crop species through genome editing technology. 展开更多
关键词 Β-IONONE Β-CAROTENE Genome editing Semi rational design
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Rational design of VHL-recruiting KRAS^(G12C) proteolysis-targeting chimeras based on molecular dynamics simulation
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作者 Shiyang Sun Ning Yang +16 位作者 Yaqiu Mao Ting Wei Pengli Wei Tingting Yang Yixin Zhang Jian Yan Changkai Jia Yi Li Xu Cai Zhiyuan Zhao Xuesong Feng Xiaomei Zhuang Wenpeng Zhang Junhai Xiao Pengyun Li Zhibing Zheng Song Li 《Chinese Chemical Letters》 2026年第2期308-313,共6页
The von Hippel-Lindau tumor suppressor(VHL)has been extensively used to develop degraders targeting numerous proteins of interest.However,studies on the rational design of VHL-proteolysis-targeting chimeras(PROTACs)re... The von Hippel-Lindau tumor suppressor(VHL)has been extensively used to develop degraders targeting numerous proteins of interest.However,studies on the rational design of VHL-proteolysis-targeting chimeras(PROTACs)remain scarce.This study aimed to develop strategies to investigate VHL-recruiting PROTACs connecting with varying attachment sites on VHL ligands,which could be utilized for KRAS^(G12C) degraders development and expanded to additional targets.We developed a molecular dynamics(MD)-based strategy to explore the stability of ternary complexes induced by KRAS^(G12C) PROTACs with four distinct attachment sites of VH032.We found a potent degrader namely YN14-H,linked to hydroxyl group on VH032 benzene ring,exhibited the most superior ability of inducing ternary complexes,reflected by the lowest dissociation constant(Kd)for ternary complex induction and the highest AlphaScreen(AS)-based interaction.YN14-H inhibited cell growth with low nanomolar half maximal inhibitory concentration(IC_(50))and half maximal degradation concentration(DC_(50))values as well as>98%of maximum degradation(D_(max))in NCI-H358 and MIA PaCa-2 cells harboring KRAS^(G12C)-mutation.Mechanistically,YN14-H significantly induced apoptosis and inhibited the migratory capacity.Notably,YN14-H demonstrated favorable pharmacokinetic properties and excellent antitumor activity in vivo.Furthermore,bromodomain-containing protein 7(BRD7)and Bruton tyrosine kinase(BTK)degraders attached to distinct sites on VH032 further verified the rationality and universality of our MD-based strategies.Our findings demonstrated that YN14-H could serve as a promising candidate for the treatment of tumors with KRAS^(G12C)-mutation and present a strategy for the rational design of VHL-recruiting PROTACs that target additional proteins at distinct attachment sites. 展开更多
关键词 PROTACs VHL KRAS^(G12C) Rational drug design Molecular dynamics
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The Study of Rationalization of the Economic Functions in Shanghai——the Study Group of the “Same topic”
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作者 IrisTam H.KChan 《China City Planning Review》 1989年第1期3-23,共21页
From the PersPective of the systemsaPProaeh,the urban eeonomie functions re-fer to the role Played by the eeonomy of theeity in its surrounding areas.Beeause of different geograPhieal loeations,historiealeonditions,th... From the PersPective of the systemsaPProaeh,the urban eeonomie functions re-fer to the role Played by the eeonomy of theeity in its surrounding areas.Beeause of different geograPhieal loeations,historiealeonditions,the various roles and funetionsof the eities in the national economy,theeeonomie funetions of a eity may be of 展开更多
关键词 The Study of rationalization of the Economic Functions in Shanghai the Study Group of the Same topic
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An Overview of Rationalization Theories of Non-simply Connected Spaces and Non-nilpotent Groups
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作者 Sergei O.IVANOV 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2022年第10期1705-1721,共17页
We give an overview of five rationalization theories for spaces(Bousfield-Kan’s Q-completion;Sullivan’s rationaliz ation;Bousifeld’s homology rationaliz ation;Casacuberta-Peschke’s Ω-rationalization;Gomez-Tato-Ha... We give an overview of five rationalization theories for spaces(Bousfield-Kan’s Q-completion;Sullivan’s rationaliz ation;Bousifeld’s homology rationaliz ation;Casacuberta-Peschke’s Ω-rationalization;Gomez-Tato-Halperin-Tanré’s π-fiberwise rationalization)that extend the classical rationalization of simply connected spaces.We also give an overview of the corresponding rationalization theories for groups(Q-completion;HQ-localization;Baumslag rationalization)that extend the classical Malcev completion. 展开更多
关键词 Rationalisation LOCALISATION rational homotopy theory group theory
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The dark side of non‑fungible tokens: understanding risks in the NFT marketplace from a fraud triangle perspective
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作者 Nitin Upadhyay Shalini Upadhyay 《Financial Innovation》 2025年第1期1719-1747,共29页
This study investigates the dark side of the non-fungible token(NFT)marketplace,with a focus on understanding the risks,and underlying factors driving fraud in the NFT ecosystem.Using the fraud triangle framework,this... This study investigates the dark side of the non-fungible token(NFT)marketplace,with a focus on understanding the risks,and underlying factors driving fraud in the NFT ecosystem.Using the fraud triangle framework,this study examines pressure,opportunity,and rationalization from individual and organizational perspectives.The research provides a comprehensive understanding of the contributing factors to NFT marketplace fraud by analyzing the reasons behind fraudulent actions.A conceptual framework is developed that includes ten propositions to aid in understanding the complexity of this issue.This study’s outcomes will assist policymakers in crafting efficient approaches to mitigate fraud within the NFT marketplace. 展开更多
关键词 NFT Blockchain Marketplace risks Opportunity Pressure rationalization Emerging technology FRAUD Fraud triangle
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Understanding Accounting Fraud Through the Fraud Triangle Theory:A Systematic Literature Review
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作者 Faisal Fadly Hermawan Iskandar Muda Sambas Ade Kesuma 《Journal of Modern Accounting and Auditing》 2025年第2期48-58,共11页
This research aims to understand the causes of fraud through the approach of the Fraud Triangle Theory,which includes three main factors:pressure,opportunity,rationalization.By using the Systematic Literature Review m... This research aims to understand the causes of fraud through the approach of the Fraud Triangle Theory,which includes three main factors:pressure,opportunity,rationalization.By using the Systematic Literature Review method from various relevant international journals,it analyzed systematically to identify patterns,trends,and theoretical contributions to efforts in detecting and preventing fraud.The results of this study show that the three factors in the Fraud Triangle Theory significantly contribute to the occurrence of fraud.Opportunity as the most dominant factor is caused by weak internal control systems and lack of oversight.In addition,economic pressure,and a permissive organizational environment,as well as the rationalization processes by individuals,also increase the tendency for a person to commit fraud.These findings emphasize the need for a comprehensive approach in fraud prevention strategies,through ethical values,the establishment of an organizational culture with integrity,and the implementation of more effective internal control and oversight. 展开更多
关键词 Fraud Triangle FRAUD PRESSURE OPPORTUNITY rationalization
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三阶段TMR育肥模式对西杂牛育肥效果的研究
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作者 徐御林 沈慈 +3 位作者 王杰 贾先波 王佳佳 赖松家 《畜禽业》 2025年第6期1-5,共5页
目的 探索三阶段全混合日粮(total mixed ration, TMR)育肥模式对西杂牛的饲喂效果。方法 试验选择平均体质量为236 kg左右的健康西杂2代公牛60头为试验动物,随机平均分为2组。试验组和对照组的日粮结构和营养水平一致,对照组按传统的... 目的 探索三阶段全混合日粮(total mixed ration, TMR)育肥模式对西杂牛的饲喂效果。方法 试验选择平均体质量为236 kg左右的健康西杂2代公牛60头为试验动物,随机平均分为2组。试验组和对照组的日粮结构和营养水平一致,对照组按传统的先粗后精饲喂模式饲喂,试验组按三阶段模式进行育肥,每阶段饲喂不同日粮结构和营养水平的日粮。结果 试验组育肥牛的末质量、总增质量和平均日增质量极显著高于对照组(p<0.01),分别为708.6 kg、472.2 kg和1.29 kg/d;屠宰率显著高于对照组(p<0.05),剪切力极显著低于对照组(p<0.01),分别为54.7%和37.04 N,试验组大部分肉牛大理石花纹等级达到A2级。结论 基于TMR料采用的三阶段育肥模式能够提高西杂牛的生长性能、屠宰性能和肉质,可为我国高档牛肉生产提供理论基础。 展开更多
关键词 西杂牛 三阶段育肥模式 全混合日粮(total mixed ration TMR) 生长性能 屠宰率 剪切力
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The(Homotopy)Fixed Point Set of S^(1)-Actions on Rationally Elliptic 4-Manifolds
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作者 Chen Huimin Liu Xiugui 《南开大学学报(自然科学版)》 北大核心 2025年第3期32-37,共6页
Let X be a closed simply connected rationally elliptic 4-manifold.The rational homotopy type of homotopy fixed point sets X^(hS^(1))is determined,and based on some relations between X^(hS^(1))and X^(S^(1)),the rationa... Let X be a closed simply connected rationally elliptic 4-manifold.The rational homotopy type of homotopy fixed point sets X^(hS^(1))is determined,and based on some relations between X^(hS^(1))and X^(S^(1)),the rational homotopy type of the fixed point set X^(S^(1))is determined. 展开更多
关键词 rationally elliptic 4-manifolds rational homotopy type homotopy fixed point set fixed point set
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The Intrinsic Tension Between Rationalism and Emotionalism:On the Modernity Connotations of Artificial Intelligence and the Metaverse
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作者 Zhang Bing 《Contemporary Social Sciences》 2025年第2期88-102,共15页
In the successive rise of the metaverse and artificial intelligence(AI),rationalism and emotionalism have consistently manifested as symptoms of modernity throughout their developmental trajectories.This paper argues ... In the successive rise of the metaverse and artificial intelligence(AI),rationalism and emotionalism have consistently manifested as symptoms of modernity throughout their developmental trajectories.This paper argues that the achievements and crises of both fields signify the triumph of rationalism in the context of deepening modernity,while simultaneously harboring an intrinsic impetus and possibility for transitioning from rationalism to emotionalism.This dynamic serves as a quintessential representation of modernity’s crises and their transcendence.Centered on embodied cognitive science,AI and the metaverse—rooted in rationalism—now face challenges in shifting toward emotionalism,revealing their inadequacy in addressing this shift.Humanity must explore new modernity-deepening paradigms grounded in emotionalism to confront and transcend the potential crises posed by the metaverse and AI. 展开更多
关键词 artificial intelligence metaverse modernity RATIONALISM EMOTIONALISM
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Employing pretreatment neutrophil-lymphocyte ratio and platelet-lymphocyte ration to evaluate chemotherapy and immunotherapy:A retrospective study of 719 cases
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作者 Xue Yang Fang Hao +1 位作者 Li-Li Zeng Dian-Sheng Zhong 《Clinical Research Communications》 2025年第2期20-25,共6页
Background:Neutrophil-lymphocyte ratio(NLR)and platelet-lymphocyte ration(PLR)have been shown to contribute to tumour progression and response to therapy.Methods:We retrospectively counted NLR and PLR in 719 patients ... Background:Neutrophil-lymphocyte ratio(NLR)and platelet-lymphocyte ration(PLR)have been shown to contribute to tumour progression and response to therapy.Methods:We retrospectively counted NLR and PLR in 719 patients with advanced malignancies receiving chemo-and/or immuno-therapy.Results:Both the pretreatment NLR and PLR were significantly elevated in patients with progressive disease than in those without progressive disease.Compared to low groups,the high NLR and PLR groups showed significantly worse event free survival.Conclusion:We propose that NLR and PLR are not only effective blood markers for predicting therapeutic responses to chemo-and/or immuno-therapy,but also useful in detecting survival in diverse malignancies. 展开更多
关键词 neutrophil-lymphocyte ratio platelet-lymphocyte ration CHEMOTHERAPY IMMUNOTHERAPY prognosis
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Rational protein engineering of thermostable heparinase I from Bacteroides thetaiotaomicron for highly efficient heparin degradation
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作者 Chuan Zhang Ruohan Zhao +6 位作者 Leilei Yu Qixiao Zhai Jianxin Zhao Hao Zhang Xuegang Luo Fengwei Tian Wei Chen 《Food Science and Human Wellness》 2025年第6期2161-2171,共11页
Heparin,a glycosaminoglycan,is a stable source of carbon that supports the growth of microorganisms in the human intestine.It is also a commonly used anticoagulant drug in clinical practice,with significant therapeuti... Heparin,a glycosaminoglycan,is a stable source of carbon that supports the growth of microorganisms in the human intestine.It is also a commonly used anticoagulant drug in clinical practice,with significant therapeutic effects.Low molecular weight heparin(LMWH)is a highly active low molecular weight fragment obtained via enzymatic reaction or the chemical degradation of heparin.LMWH has been applied globally in the prevention and treatment of venous thromboembolism in thrombosis patients.Simultaneously,as a potential prebiotic,because of its low molecular weight,LMWH can be well degraded by the gut microbiota to maintain intestinal balance.Enzymatic heparin degradation has recently emerged as a viable disposal method for LMWH preparation;however,only very few benchmark enzymes have been thoroughly described and subjected to protein engineering to improve their properties over the past few years.The commercialization of enzymes will require the development of robustly engineered enzymes that meet the demands of industrial processes.Herein,we report a rational protein engineering strategy that includes molecular dynamic simulations of flexible amino acid mutations and disulfide bond screening.Several Bacteroides thetaiotaomicron heparanase I(Bt-HepI)mutants were obtained and screened for high thermal stability.We obtained the Bt-HepI^(D204C/K208C/H189W/Q198R)variant,which features a stabilized protein surface structure,with a 1.3-fold increase in catalytic constant/michaelis-menten constant(k_(cat)/K_(m)),a 2.44-fold increase in thermal stability at 50℃,and a 1.8-fold decrease in the average molecular weight of LMWH produced at 40℃compared with that seen with Bt-HepI^(WT).Our study establishes a strategy to engineer thermostable HepI to underpin its industrial applications. 展开更多
关键词 HEPARIN Bacteroides thetaiotaomicron Heparinase I Rational protein engineering Thermostability
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Theoretical insight into the active sites for chlorobenzene oxidation:From phosphate to M_(3)clusters
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作者 Jin Li Xin Chen +2 位作者 Aling Chen Zhi-Qiang Wang Dengsong Zhang 《Chinese Chemical Letters》 2025年第8期636-640,共5页
Chlorobenzene is a model molecule for researching harmful chlorinated volatile organic compounds.Designing the chemical adsorption site for complex molecules such as chlorobenzene is challenging without a large datase... Chlorobenzene is a model molecule for researching harmful chlorinated volatile organic compounds.Designing the chemical adsorption site for complex molecules such as chlorobenzene is challenging without a large dataset and reasonable descriptors.Here,the adsorption of chlorobenzene on a phosphorylated CeO_(2)catalyst was analyzed using density functional theory calculations.Three different surface phosphate(H_(x)PO_(4))models were constructed and used to adsorb chlorobenzene.An orbital interaction with fully occupied antibonding is found in one of three physical adsorptions.Based on this,the surface sites of a tri-cluster(M_(3))located at the CeO_(2)surface have been suggested to activate chlorobenzene.Three different clusters have been tested,namely Fe_(3),Ru_(3),and B_(3).All these clusters can activate and twist chlorobenzene by donating electrons.Fe_(3)and Ru_(3)form bonds with weak covalent and strong ionic characters,while B3forms strong covalent bonds between boron and carbon.This work not only predicts a class of sites for chlorobenzene activation that may prevent polychlorinated by-products but also gives a template for catalyst rational design according to fundamental catalytic theory. 展开更多
关键词 Catalysts rational design CHLOROBENZENE Activation Tri-cluster Density functional theory
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