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Vibration Control of A Flexible Marine Riser System Subject to Input Dead Zone and Extraneous Disturbances 被引量:1
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作者 ZHOU Li WANG Guo-rong WAN Min 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期271-284,共14页
An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control... An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller. 展开更多
关键词 adaptive backstepping control disturbance observer flexible marine riser input dead zone vibration control
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SEI/dead Li-turning capacity loss for high-performance anode-free solid-state lithium batteries
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作者 Qianwen Yin Tianyu Li +3 位作者 Hongzhang Zhang Guiming Zhong Xiaofei Yang Xianfeng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期145-152,共8页
Anode-free solid-state lithium metal batteries(AF-SSLBs)have the potential to deliver higher energy density and improved safety beyond lithium-metal batteries.However,the unclear mechanism for the fast capacity decay ... Anode-free solid-state lithium metal batteries(AF-SSLBs)have the potential to deliver higher energy density and improved safety beyond lithium-metal batteries.However,the unclear mechanism for the fast capacity decay in AF-SSLBs,either determined by dead Li or solid electrolyte interface(SEI),limits the proposal of effective strategies to prolong cycling life.To clarify the underlying mechanism,herein,the evolution of SEI and dead Li is quantitatively analyzed by a solid-state nuclear magnetic resonance(ss-NMR)technology in a typical LiPF6-based polymer electrolyte.The results show that the initial capacity loss is attributed to the formation of SEI,while the dead Li dominates the following capacity loss and the growth rate is 0.141 mA h cm^(−2)cycle−1.To reduce the active Li loss,the combination of inorganic-rich SEI and self-healing electrostatic shield effect is proposed to improve the reversibility of Li deposition/dissolution behavior,which reduces the capacity loss rate for the initial SEI and following dead Li generation by 2.3 and 20.1 folds,respectively.As a result,the initial Coulombic efficiency(ICE)and stable CE increase by 15.1%and 15.3%in Li-Cu cells,which guides the rational design of high-performance AF-SSLBs. 展开更多
关键词 Solid-state lithium batteries Solid-state NMR Anode-free SEI Dead Li
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Improved model on asynchronous measurement-device-independent quantum key distribution with realistic devices
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作者 Mingshuo Sun Chun-Hui Zhang +3 位作者 Rui Zhang Xing-Yu Zhou Jian Li Qin Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期52-56,共5页
In principle,the asynchronous measurement-device-independent quantum key distribution(AMDI-QKD)can surpass the key rate capacity without phase tracking and phase locking.However,practical imperfections in sources or d... In principle,the asynchronous measurement-device-independent quantum key distribution(AMDI-QKD)can surpass the key rate capacity without phase tracking and phase locking.However,practical imperfections in sources or detections would dramatically depress its performance.Here,we present an improved model on AMDI-QKD to reduce the influence of these imperfections,including intensity fluctuation,the afterpulse effect,and the dead time of detectors.Furthermore,we carry out corresponding numerical simulations.Simulation results show that,by implementing our present work,it can have more than 100 km longer secure transmission distance and one order of magnitude enhancement in the key generation rate after 320 km compared with the standard method.Moreover,our model can still break the Pirandola–Laurenza–Ottaviani–Banchi(PLOB)bound even under realistic experimental conditions. 展开更多
关键词 asynchronous measurement-device-independent quantum key distribution intensity fluctuations afterpulse dead time
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Monte Carlo method for evaluation of surface emission rate measurement uncertainty
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作者 Yuan-Qiao Li Min Lin +4 位作者 Li-Jun Xu Rui Luo Yu-He Zhang Qian-Xi Ni Yun-Tao Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第7期126-136,共11页
The aim of this study is to evaluate the uncertainty of 2πα and 2πβ surface emission rates using the windowless multiwire proportional counter method.This study used the Monte Carlo method (MCM) to validate the co... The aim of this study is to evaluate the uncertainty of 2πα and 2πβ surface emission rates using the windowless multiwire proportional counter method.This study used the Monte Carlo method (MCM) to validate the conventional Guide to the Expression of Uncertainty in Measurement (GUM) method.A dead time measurement model for the two-source method was established based on the characteristics of a single-channel measurement system,and the voltage threshold correction factor measurement function was indirectly obtained by fitting the threshold correction curve.The uncertainty in the surface emission rate was calculated using the GUM method and the law of propagation of uncertainty.The MCM provided clear definitions for each input quantity and its uncertainty distribution,and the simulation training was realized with a complete and complex mathematical model.The results of the surface emission rate uncertainty evaluation for four radioactive plane sources using both methods showed the uncertainty’s consistency E_(n)<0.070 for the comparison of each source,and the uncertainty results of the GUM were all lower than those of the MCM.However,the MCM has a more objective evaluation process and can serve as a validation tool for GUM results. 展开更多
关键词 Surface emission rate Monte Carlo method METROLOGY Probability distribution function Dead time Low-energy loss correction Least-squares method
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肝细胞肝癌中DDX24、TRIP12表达与上皮间质转化及临床预后的关系
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作者 井丽君 张敏 +1 位作者 魏雪 唐玉彬 《疑难病杂志》 CAS 2024年第6期646-652,共7页
目的探讨肝细胞肝癌(HCC)中DEAD盒解旋酶24(DDX24)、甲状腺激素受体相互作用因子12(TRIP12)表达,分析两者与上皮间质转化(EMT)及临床预后的关系。方法回顾性选取2019年2月—2021年1月中国人民解放军联勤保障部队第九四〇医院肝胆外科手... 目的探讨肝细胞肝癌(HCC)中DEAD盒解旋酶24(DDX24)、甲状腺激素受体相互作用因子12(TRIP12)表达,分析两者与上皮间质转化(EMT)及临床预后的关系。方法回顾性选取2019年2月—2021年1月中国人民解放军联勤保障部队第九四〇医院肝胆外科手术治疗的HCC患者96例。免疫组化检测癌组织和癌旁组织DDX24、TRIP12蛋白表达;采用实时荧光定量PCR检测DDX24、TRIP12和EMT指标[E-钙黏素(E-cad)、N-钙黏素(N-cad)及TWIST]表达;Pearson相关分析DDX24 mRNA、TRIP12 mRNA和EMT指标的相关性;绘制Kaplan-Meier曲线,Log-Rank检验分析DDX24 mRNA、TRIP12 mRNA高表达组和低表达组HCC患者预后的差异;多因素Cox比例风险模型分析影响HCC患者死亡预后的独立因素。结果HCC癌组织中DDX24、TRIP12阳性率显著高于癌旁组织(χ^(2)/P=109.714/<0.001,108.755/<0.001);与癌旁组织比较,HCC癌组织中DDX24、TRIP12、N-cad、TWIST mRNA表达较高,E-cad mRNA表达较低,差异均有统计学意义(t/P=35.810/<0.001,48.036/<0.001,25.015/<0.001,48.482/<0.001,38.069/<0.001)。HCC癌组织中DDX24 mRNA与TRIP12 mRNA表达呈正相关(r=0.701,P<0.001);DDX24 mRNA、TRIP12 mRNA均与N-cad mRNA、TWIST mRNA呈正相关,与E-cad mRNA呈负相关(r/P=0.723/<0.001,0.661/<0.001,0.706/<0.001,0.745/<0.001,-0.694/<0.001,-0.609/<0.001)。低分化程度、CNLC分期Ⅱ~Ⅲ期和有血管侵犯HCC患者癌组织中DDX24、TRIP12 mRNA高于高中分化程度、CNLC分期Ⅰ期和无血管侵犯者(DDX24:t/P=10.348/<0.001,18.474/<0.001,6.302/<0.001;TRIP12:t/P=25.661/<0.001,36.396/<0.001,14.928/<0.001)。DDX24 mRNA高表达组和低表达组3年总生存率分别为39.13%(18/46)、64.00%(32/50),2组生存曲线总体比较,差异具有统计学意义(Log rankχ^(2)=7.491,P=0.006);TRIP12 mRNA高表达组和低表达组3年总生存率分别为36.17%(17/47)、67.35%(33/49),2组生存曲线总体比较,差异有统计学意义(Log rankχ^(2)=8.146,P=0.004)。CNLC分期Ⅱ~Ⅲ期、低分化程度、血管侵犯、DDX24 mRNA高表达、TRIP12 mRNA高表达是影响HCC患者死亡预后的危险因素[HR(95%CI)=1.611(1.175~2.209),1.768(1.238~2.526),1.464(1.089~1.968),1.859(1.330~2.599),1.775(1.275~2.473)]。结论HCC癌组织中DDX24、TRIP12表达上调,与N-cad、TWIST呈正相关,与E-cad呈负相关,DDX24、TRIP12可能通过促进HCC肿瘤EMT的发生,促进HCC肿瘤的恶性进展,两者是影响HCC患者死亡预后的独立危险因素。 展开更多
关键词 肝细胞肝癌 DEAD盒解旋酶24 甲状腺激素受体相互作用因子12 上皮间质转化 临床预后
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转录因子HNF1A、HNF4A和FOXA2调节肝细胞蛋白质N-糖基化
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作者 Vedrana Vicic Bockor Nika Foglar +7 位作者 Goran Josipovic Marija Klasic Ana Vujic Branimir Plavsa Toma Keser Samira Smajlovic Aleksandar Vojta Vlatka Zoldos 《Engineering》 SCIE EI CAS CSCD 2024年第1期57-68,共12页
Hepatocyte nuclear factor 1 alpha(HNF1A),hepatocyte nuclear factor 4 alpha(HNF4A),and forkhead box protein A2(FOXA2)are key transcription factors that regulate a complex gene network in the liver,cre-ating a regulator... Hepatocyte nuclear factor 1 alpha(HNF1A),hepatocyte nuclear factor 4 alpha(HNF4A),and forkhead box protein A2(FOXA2)are key transcription factors that regulate a complex gene network in the liver,cre-ating a regulatory transcriptional loop.The Encode and ChIP-Atlas databases identify the recognition sites of these transcription factors in many glycosyltransferase genes.Our in silico analysis of HNF1A,HNF4A.and FOXA2 binding to the ten candidate glyco-genes studied in this work confirms a significant enrich-ment of these transcription factors specifically in the liver.Our previous studies identified HNF1A as a master regulator of fucosylation,glycan branching,and galactosylation of plasma glycoproteins.Here,we aimed to functionally validate the role of the three transcription factors on downstream glyco-gene transcriptional expression and the possible effect on glycan phenotype.We used the state-of-the-art clus-tered regularly interspaced short palindromic repeats/dead Cas9(CRISPR/dCas9)molecular tool for the downregulation of the HNF1A,HNF4A,and FOXA2 genes in HepG2 cells-a human liver cancer cell line.The results show that the downregulation of all three genes individually and in pairs affects the transcrip-tional activity of many glyco-genes,although downregulation of glyco-genes was not always followed by an unambiguous change in the corresponding glycan structures.The effect is better seen as an overall change in the total HepG2 N-glycome,primarily due to the extension of biantennary glycans.We propose an alternative way to evaluate the N-glycome composition via estimating the overall complexity of the glycome by quantifying the number of monomers in each glycan structure.We also propose a model showing feedback loops with the mutual activation of HNF1A-FOXA2 and HNF4A-FOXA2 affecting glyco-genes and protein glycosylation in HepG2 cells. 展开更多
关键词 Clustered regularly interspaced short palindromic repeats/dead Cas9(CRISPR/dCas9) EPIGENETICS Hepatocyte nuclear factor 1 alpha(HNF1A) Hepatocyte nuclear factor 4 alpha(HNF4A) Forkhead box protein A2(FOXA2) N-GLYCOSYLATION HepG2 cells
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The “Dead Universe” Theory: Natural Separation of Galaxies Driven by the Remnants of a Supermassive Dead Universe
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作者 Joel Almeida 《Natural Science》 2024年第6期65-101,共37页
This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This per... This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This perspective challenges the conventional Big Bang theory, particularly concerning dark matter, the expansion of the universe, and the interpretation of phenomena such as gravitational waves. 展开更多
关键词 Dead Universe Theory Heat Death of the Universe Big Bang Theory Universe’s Ultimate Fate Universe Expansion Big Freeze Universe Cosmological Models End of Universe Theories Natural Galaxy Drift Future of the Universe Universe Cooling Down Cosmology and Entropy
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Formulating Dead Sea Mud in Cosmetic Products, Its Effects on Skin, and the Underlying Biological Mechanism: A Review
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作者 Ze’evi Ma’or Dror Cohen Assaf Assis 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第3期276-288,共13页
Research Background: The marketing of cosmetic products derived from Dead Sea (DS) mud has undergone significant evolution, transforming from simple souvenirs into a large-scale cosmetic industry offering a diverse ar... Research Background: The marketing of cosmetic products derived from Dead Sea (DS) mud has undergone significant evolution, transforming from simple souvenirs into a large-scale cosmetic industry offering a diverse array of products. DS mud is utilized both as pure mud for home spa treatments and as an active ingredient in cosmetic and cosmeceutical formulations. Its global appeal is largely due to its natural, health-oriented image, which aligns with consumer preferences and provides assurance regarding its use in skincare. Research Objectives: This review examines the published data related to the rationale for formulating DS mud in cosmetics, the biological and cosmetic effects of DS mud on the skin, and the speculated bio-mechanisms underlying these effects. Methods: We screened relevant literature on DS mud collected from the shores of the Dead Sea in Jordan and Israel. Publications on mineral muds excavated in different locations around the globe, as well as studies on the biological mechanisms of other DS minerals, were also reviewed as indications and supportive recommendations. Summarizing the vast collected data into a comprehensive review was undertaken to expose readers to the various aspects of DS mud in cosmetics. Results: The primary reason for formulating DS mud in skincare products is its deep cleansing and skin detoxification properties. Consequently, it is often incorporated into rinse-off masks, soaps, and scrubbing products. Additionally, DS mud is used in leave-on products and sheet masks. Cosmeceutical applications of DS mud, recommended for various skin conditions, offer complementary treatments to improve the quality of life for people with skin diseases. The physicochemical and biological effects of DS mud are driven by its rich mineral ion composition, including magnesium, calcium, sodium, potassium, zinc, and strontium—elements known to improve skin barrier function, enhance hydration, and reduce inflammation. The high salt concentration induces moderate ionic osmotic stress, stimulating cellular growth and hydration pathways. Moreover, DS mud’s anti-microbial properties further contribute to its therapeutic potential. Ongoing innovations in formulation techniques continue to expand the applications of DS mud, including blending it with other active ingredients, developing novel application methods, and refining manufacturing processes to improve product quality and efficacy. Conclusions: DS mud remains a valuable ingredient in modern skincare due to its rich mineral content and therapeutic properties. Ongoing research and technological advancements promise further innovations, reinforcing its status as a natural and effective component in the global cosmetics industry. 展开更多
关键词 Dead Sea MINERAL COSMETICS MUD Health
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From Finnish Assortment Pricing to Market Economy Using Prices for Sawn Wood and Chips in Reference Bucking
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作者 Juha Lappi 《Open Journal of Forestry》 2024年第3期233-280,共48页
Dominant Finnish assortment pricing gives prices for sawlog and pulp wood volumes. Buyers buck stems to sawlogs using secret price matrices. Agreed dimensions allow wide range of sawlog volumes. Forest owners cannot o... Dominant Finnish assortment pricing gives prices for sawlog and pulp wood volumes. Buyers buck stems to sawlogs using secret price matrices. Agreed dimensions allow wide range of sawlog volumes. Forest owners cannot objectively compare biddings: timber trade is a lottery game. Bucking is analyzed in terms of sawlog, pulp wood, log cylinder, sawn wood, value-weighted sawn wood, and chips. Sawn wood and its value are computed from top diameter of the sawlog. Profit maximization requires buyers to buck logs producing smaller than maximal value, causing dead weight loss. Nominal assortment prices have unpredictable relation to effective stumpage price. Assortment pricing does not meet requirements of market economy. If sawmills linked to pulp mills buck smaller sawlog percentages than independent sawmills, as generally believed, they use higher price for chips in their own harvests than they pay for independent sawmills, indicating imperfect competition for chips. Sawn wood potential pricing is suggested which gives prices for sawn wood and chips coming both from sawlogs and pulp wood in reference bucking which maximizes sawn wood for given minimum and maximum log length and minimum top diameter. Simple algorithm generates feasible bucking schedules from which optimum can be selected using any objective. Pricing produces unit price for all commercial wood utilizing ratio of theoretical sawn wood and commercial volume in stand. Unit price can be compared to stem pricing and could be compared to assortment pricing if assortment pricing would produce predictable sawlog percentages. Sawn wood potential pricing is concrete, transparent, easy to compute, considers stem size and tapering, reduces trading cost and is less risky to buyers than stem pricing. It meets requirements of market economy. Readers can repeat computations using open-source software Jlp22. 展开更多
关键词 Sawmill Pulp Mill Jlp22 Dead Weight Loss Stem Price
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The Need for International Cooperation between Israel and Other Middle East Nations to Protect the Jordan River Landscape
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作者 Kenneth Ray Olson 《Open Journal of Soil Science》 2024年第5期283-307,共25页
The Jordan River, also referred to as Nahr Al Sharieat in Arabic, is a long river in the Middle East that flows from north to south through the Sea of Galilee to the Dead Sea. The Jordan River is bordered by the Golan... The Jordan River, also referred to as Nahr Al Sharieat in Arabic, is a long river in the Middle East that flows from north to south through the Sea of Galilee to the Dead Sea. The Jordan River is bordered by the Golan Heights and the Hashemite Kingdom of Jordan in the east and by Israel and the Palestinian West Bank (Judea and Samaria) in the west. Soil tunnels, including those in the Jordan River watershed and on the Israel, Syria, and Lebanon borders, have a long history of use for warfare, as invasion pathways, smuggling, and storage of rockets, missiles and ordnance and are causes of serious political tension between the countries. Soil tunnel construction and destruction often has adverse environmental and human health impacts in the Jordan River landscape. Due to agricultural wastes, the discharge of untreated sewage, and diversion of saline springs into the river water there has been serious deterioration in the water quality in the lower courses of the Jordan River. The primary objective of this research is to encourage the development of a multi-country clean-up, mitigation, and protection plan for the Jordan River. 展开更多
关键词 Jordan River JORDAN Israel Lebanon SYRIA Dead Sea Sea of Galilee Six-Day War Soil Tunnels
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不同温度及厌氧/好氧运行条件对聚磷菌衰减特性的影响 被引量:7
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作者 苗志加 薛桂松 +2 位作者 翁冬晨 曹贵华 彭永臻 《土木建筑与环境工程》 CSCD 北大核心 2013年第2期113-117,123,共6页
以富含90%±2%纯度聚磷菌(PAOs)的强化生物除磷系统(EBPR)为研究对象,考察了10℃厌氧、10℃好氧、20℃厌氧、20℃好氧4种运行条件下PAOs的衰减特征。结果表明:温度越高对应衰减速率越快,4个系统在1~9d里衰减速率的平均值分别为:10... 以富含90%±2%纯度聚磷菌(PAOs)的强化生物除磷系统(EBPR)为研究对象,考察了10℃厌氧、10℃好氧、20℃厌氧、20℃好氧4种运行条件下PAOs的衰减特征。结果表明:温度越高对应衰减速率越快,4个系统在1~9d里衰减速率的平均值分别为:10℃厌氧:0.053/d;10℃好氧:0.050/d;20℃厌氧:0.072/d;20℃好氧:0.145/d。其中4个系统由于细胞死亡引起的活性衰减速率分别为:10℃厌氧:0.019/d;10℃好氧:0.017/d;20℃厌氧:0.019/d;20℃好氧:0.03/d,占总活性衰减的比例分别为:35.8%、34%、26.4%、20.7%。在9d饥饿衰减期间,污泥中所含PHA与糖原的量总体呈下降趋势。相同温度下,糖原在厌氧衰减过程中降解速率大于好氧;在同样的厌氧、好氧衰减条件下,温度越高糖原降解速率越快。 展开更多
关键词 聚磷菌 强化生物除磷 衰减速率 LIVE DEAD染色 聚羟基烷酸 糖原
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污水生物处理系统细菌衰减特征的实验研究 被引量:5
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作者 郝晓地 朱景义 +1 位作者 曹秀芹 曹亚莉 《环境科学》 EI CAS CSCD 北大核心 2008年第11期3104-3109,共6页
通过衰减速率测定实验和LIVE/DEAD细胞活性染色实验,分析了污水生物处理系统中细菌在好氧环境下的衰减状态.研究发现,细菌的衰减实质上是由生物量减少引起的数量衰减和由细胞活性降低引起的活性衰减两部分构成的.结果表明,硝化系统细菌... 通过衰减速率测定实验和LIVE/DEAD细胞活性染色实验,分析了污水生物处理系统中细菌在好氧环境下的衰减状态.研究发现,细菌的衰减实质上是由生物量减少引起的数量衰减和由细胞活性降低引起的活性衰减两部分构成的.结果表明,硝化系统细菌在衰减过程中由细胞活性降低引起的衰减约占60%,由细胞死亡引起的衰减约占40%;而在异养系统中由活性降低引起的衰减和由细胞死亡引起的衰减分别为80%和20%. 展开更多
关键词 污水生物处理 细胞衰减 细胞死亡 活性降低 LIVE/DEAD染色
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Dead Reckoning技术在网络游戏中的应用 被引量:3
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作者 梁白鸥 陈雷霆 蔡洪斌 《计算机应用研究》 CSCD 北大核心 2007年第9期231-232,314,共3页
介绍了基于物理运动学算法的预测技术以及基于Cubic Splines算法的平滑处理技术,并给出了Dead Reckoning在网络游戏中应用的具体算法以及该算法的相应实例。
关键词 DEAD Reckoning 网络延迟 网络游戏 客户端预测 平滑处理
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卡尔曼滤波实现车载GPS/DR组合导航 被引量:6
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作者 孙希延 纪元法 施浒立 《现代电子技术》 2006年第11期149-152,共4页
陆地车辆是在二维平面内运动的,而在车载GPS接收机和DR组合装置中,测量值是在不同的坐标系中得到的,通过对坐标系转换和测量误差分析得到组合系统的整体状态方程和测量方程,由于这些状态方程和测量方程都是关于状态的非线性函数,用广义... 陆地车辆是在二维平面内运动的,而在车载GPS接收机和DR组合装置中,测量值是在不同的坐标系中得到的,通过对坐标系转换和测量误差分析得到组合系统的整体状态方程和测量方程,由于这些状态方程和测量方程都是关于状态的非线性函数,用广义卡尔曼滤波器来实现GPS/DR组合导航的实时求解。最后在行驶车辆上采集数据并进行仿真试验,结果表明这种组合系统能够大大提高系统实时定位精度和容错能力。 展开更多
关键词 GPS DR(Dead—reckoning) 广义卡尔曼滤波 组合导航
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DEAD box家族蛋白与大肠癌 被引量:4
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作者 沈翠翠 黄培 《世界华人消化杂志》 CAS 2016年第18期2811-2816,共6页
大肠癌是常见的消化系肿瘤之一,严重威胁着人类健康.DEAD box家族在RNA加工过程中发挥重要作用,能够利用水解ATP产生的能量参与前mRNA剪接、翻译起始、mRNA转运、核蛋白体生成、RNA降解以及线粒体和细胞核内RNA转录后加工等生物学过程.... 大肠癌是常见的消化系肿瘤之一,严重威胁着人类健康.DEAD box家族在RNA加工过程中发挥重要作用,能够利用水解ATP产生的能量参与前mRNA剪接、翻译起始、mRNA转运、核蛋白体生成、RNA降解以及线粒体和细胞核内RNA转录后加工等生物学过程.已有研究表明多种RNA螺旋酶在肿瘤中表达失调,部分RNA螺旋酶参与细胞分化、细胞周期、细胞凋亡、癌基因表达和肿瘤耐药基因表达的调控.本文就DEAD box对大肠癌生理、生化影响的研究进展作一简要综述. 展开更多
关键词 DEAD box家族 大肠癌 作用机制
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紫杉烷与铂类联合化疗对上皮性卵巢癌患者血清HE4、AFP、DDX4、CD133、CEA及T细胞亚群变化的影响 被引量:7
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作者 王璐 杨文静 《海南医学院学报》 CAS 2016年第18期2153-2156,共4页
目的:探讨紫杉烷与铂类联合化疗对上皮性卵巢癌(EOC)患者血清人附睾分泌蛋白4(HE4)、甲胎蛋白(AFP)、DEAD家族多肽4(DDX4)、分化抗原簇蛋白133(CD133)、癌胚抗原(CEA)及T细胞亚群的变化的影响。方法:选择2014年10月~2016年1月在江汉大... 目的:探讨紫杉烷与铂类联合化疗对上皮性卵巢癌(EOC)患者血清人附睾分泌蛋白4(HE4)、甲胎蛋白(AFP)、DEAD家族多肽4(DDX4)、分化抗原簇蛋白133(CD133)、癌胚抗原(CEA)及T细胞亚群的变化的影响。方法:选择2014年10月~2016年1月在江汉大学附属医院确诊的80例EOC患者,随机分为实验组和对照组,各40例。对照组患者单纯给予顺铂化疗,实验组患者给予紫杉醇联合铂类化疗方案,21 d为1个疗程,两组患者均给予治疗4个疗程。评价并比较两组患者临床疗效。检测并比较两组患者化疗前后血清HE4、AFP、DDX4、CD133、CEA水平以及外周血CD3^+、CD4^+、CD8^+细胞所占的比值。结果:治疗前,两组患者血清HE4、AFP、CEA、DDX4及CD133水平比较差异无统计学意义(P>0.05);治疗后,两组患者血清HE4、AFP、CEA、DDX4及CD133水平均明显低于治疗前,同时实验组患者上述各血清肿瘤标志物水平均明显低于对照组,差异具有统计学意义(P<0.05)。治疗前,两组患者外周血CD3^+、CD4^+、CD8^+细胞所占比值比较差异无统计学意义(P>0.05);治疗后,两组患者外周血CD3^+、CD4^+、CD8^+细胞所占比值均明显低于治疗前,同时实验组患者各细胞免疫功能指标均明显高于对照组,差异具有统计学意义(P<0.05)。结论:紫杉烷与铂类联合化疗能明显降低EOC患者血清HE4、AFP、CEA、DDX4及CD133水平,升高T细胞亚群水平,改善患者细胞免疫功能,值得在临床上推广应用。 展开更多
关键词 上皮性卵巢癌 紫杉烷 铂类 人附睾分泌蛋白4 甲胎蛋白 DEAD家族多肽4 分化抗原簇蛋白133 癌胚抗原 T淋巴细胞亚群
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恶性疟原虫abstrakt同源基因的克隆及DEAD盒家族蛋白的序列分析(英文) 被引量:1
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作者 宋平 张竞男 +3 位作者 Pawan MALHOTRA Narendra TUTEJA Virender Singh CHAUHAN 李奎 《动物学报》 SCIE CAS CSCD 北大核心 2004年第3期420-430,共11页
DEAD盒蛋白家族的ATP依赖性的RNA解旋酶类参与细胞内几乎所有的RNA代谢过程 ,在几乎所有生物的细胞生长发育过程中扮演着众多不可或缺的角色。在本实验中 ,通过PCR和探针杂交相结合的筛选方法 ,筛选恶性疟原虫 (Plasmodiumfalciparum)... DEAD盒蛋白家族的ATP依赖性的RNA解旋酶类参与细胞内几乎所有的RNA代谢过程 ,在几乎所有生物的细胞生长发育过程中扮演着众多不可或缺的角色。在本实验中 ,通过PCR和探针杂交相结合的筛选方法 ,筛选恶性疟原虫 (Plasmodiumfalciparum)的基因组文库 ,克隆了FH1F———abstrakt同源基因的完整序列。通过搜索已经完成测序的恶性疟原虫基因组数据库 ,推测FH1F序列定位在第 5条染色体上。FH1F全长2 80 4bp,包含一个 1 1 6 1bp的完整阅读框 ,编码一个由 386个氨基酸组成的蛋白。对FH1F蛋白序列用BlastP进行搜索和分析以及用DNAStar与许多典型的DEAD盒蛋白序列进行比对分析 ,结果均提示FH1F蛋白应该是DEAD盒家族的一个Abstrakt蛋白。另一方面 ,用DNAStar对已知所有完整的DEAD盒蛋白进行详细的序列分析以及用Mega对这些序列进行系统发育研究的结果都显示 :DEAD盒家族的蛋白聚类成为若干不同的亚群 ;与DEAD盒蛋白的一般保守序列相比 ,Abstrakt,eIF 4A ,Vasa ,P6 8等不同亚群的DEAD盒蛋白在保守区具有各自不同的结构特征。本文对不同的DEAD盒蛋白的结构特征进行了总结并试图给出不同亚群分类上的结构标准 。 展开更多
关键词 恶性疟原虫 abstrakt 同源基因 克隆 DEAD盒 序列分析 RNA解旋酶
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miR-34a-3p、DDX27在结直肠癌组织中的表达水平及临床意义 被引量:2
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作者 周明慧 宁剑伟 袁维堂 《现代肿瘤医学》 CAS 北大核心 2021年第23期4159-4164,共6页
目的:检测结直肠癌患者组织中微小RNA-34a-3p(miR-34a-3p)、DEAD盒多肽27(DDX27)的表达水平,并探讨二者表达水平与结直肠癌预后的相关性。方法:选取2016年01月至2017年04月于本院住院的102例结直肠癌癌组织作为结直肠癌组,选取其癌旁正... 目的:检测结直肠癌患者组织中微小RNA-34a-3p(miR-34a-3p)、DEAD盒多肽27(DDX27)的表达水平,并探讨二者表达水平与结直肠癌预后的相关性。方法:选取2016年01月至2017年04月于本院住院的102例结直肠癌癌组织作为结直肠癌组,选取其癌旁正常组织作为癌旁对照组。采用实时荧光定量PCR(qRT-PCR)法检测组织miR-34a-3p、DDX27 mRNA表达水平;分析结直肠癌患者组织中miR-34a-3p、DDX27 mRNA表达水平与患者临床病理特征的关系;Kaplan-Meier法分析结直肠癌组织中miR-34a-3p、DDX27表达水平与患者生存率的相关性;多因素Cox回归分析影响结直肠癌预后的因素。结果:Targetscan网站在线预测结果显示miR-34a-3p与DDX27的3’UTR之间存在碱基互补关系。双荧光素酶实验结果显示,与miR-NC相比,miR-34a-3p-mimics与野生型3’UTR区(WT-DDX27)共转出现了荧光减弱,而与突变3’UTR区(MUT-DDX27)共转后荧光强度未出现明显变化;Ualcan数据库中,结肠癌组织中DDX27水平高于正常结肠组织(P <0.05);结直肠癌组DDX27 mRNA水平高于癌旁对照组,miR-34a-3p水平低于癌旁对照组(P <0.05),且DDX27表达趋势与Ualcan数据库一致;miR-34a-3p、DDX27表达与肿瘤大小、组织分化程度、淋巴结转移、TNM分期有关(P <0.05);miR-34a-3p低表达组三年内存活率(64.00%)低于高表达组(94.23%),DDX27高表达组三年内存活率(66.67%)低于低表达组(92.16%),差异均有统计学意义(P <0.05);DDX27、组织分化程度、TNM分期是影响结直肠癌不良预后的独立危险因素(P <0.05),miR-34a-3p是影响结直肠癌不良预后的保护因素(P <0.05)。结论:结直肠癌组织中miR-34a-3p、DDX27表达水平与组织分化程度、TNM分期等临床病理特征密切相关,且均是影响结直肠癌预后的因素,可对结直肠癌的病情评价及治疗提供一定理论依据。 展开更多
关键词 结直肠癌 组织 微小RNA-34a-3p DEAD盒多肽27
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甲醛固定对Live/Dead BacLight Bacterial Viability Kit死活细菌染液荧光显微计数海洋细菌的影响 被引量:2
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作者 张瑜斌 崔焱芸 +1 位作者 郑运 孙省利 《生态科学》 CSCD 北大核心 2013年第5期636-641,共6页
利用Live/Dead BacLight Bacterial Viability Kit死活细菌染液对采自湛江东海大堤海水、沉积物细菌和大型海藻拟刚毛藻(Cladophoropsis zollingeri)内生细菌数量进行了甲醛固定处理前后的荧光显微计数对比分析。结果表明,新鲜样品(不... 利用Live/Dead BacLight Bacterial Viability Kit死活细菌染液对采自湛江东海大堤海水、沉积物细菌和大型海藻拟刚毛藻(Cladophoropsis zollingeri)内生细菌数量进行了甲醛固定处理前后的荧光显微计数对比分析。结果表明,新鲜样品(不加甲醛固定)、甲醛刚固定样品、甲醛固定1周样品和甲醛固定2周样品中海洋细菌数量差异不显著(p>0.05)。甲醛固定对Live/Dead BacLight Bacterial Viability Kit死活细菌染液荧光显微计数海洋细菌数量无显著影响,固定后的样品可在2周内完成计数。 展开更多
关键词 甲醛固定 LIVE DEAD BacLight Bacterial Viability Kit染液 细菌荧光显微计数
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DEAD盒多肽43在肺腺癌组织中的表达 被引量:1
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作者 崔黎 崔莹 +1 位作者 赵娜 陈奎生 《肿瘤基础与临床》 2020年第4期294-297,共4页
目的探讨DEAD盒多肽43(DDX43)在肺腺癌组织中的表达。方法应用免疫组化、荧光原位杂交技术观察DDX43在正常肺组织、肺泡上皮非典型腺瘤样增生及肺腺癌组织中表达情况,并对其数据进行比较分析。结果正常肺组织、肺泡上皮非典型腺瘤样增... 目的探讨DEAD盒多肽43(DDX43)在肺腺癌组织中的表达。方法应用免疫组化、荧光原位杂交技术观察DDX43在正常肺组织、肺泡上皮非典型腺瘤样增生及肺腺癌组织中表达情况,并对其数据进行比较分析。结果正常肺组织、肺泡上皮非典型腺瘤样增生、肺腺癌组织中DDX43蛋白的阳性表达率分别为0.00%、38.71%、88.71%,总体比较差异有统计学意义(χ^2=63.150,P<0.001)。正常肺组织、肺泡上皮非典型腺瘤样增生、肺腺癌组织中DDX43 mRNA的阳性表达率分别为8.06%、38.71%、82.26%,总体比较差异有统计学意义(χ^2=53.124,P<0.001)。肺腺癌组织中DDX43蛋白和mRNA的表达均与其有无淋巴结转移、胸膜侵犯、脉管侵犯有关(蛋白χ^2=3.214,P=0.040;χ^2=14.230,P=0.001;χ^2=10.400,P=0.001;mRNAχ^2=4.590,P=0.030;χ^2=6.223,P=0.008;χ^2=10.400,P=0.001)。结论肺腺癌组织中DDX43高表达,DDX43蛋白、mRNA表达与肺腺癌的发生、发展、浸润、转移有关。 展开更多
关键词 DEAD盒多肽43 肺腺癌 免疫组化 荧光原位杂交
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