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A Nonlinear Multi-Scale Interaction Model for Atmospheric Blocking:A Tool for Exploring the Impact of Changing Climate on Mid-to-High Latitude Weather Extremes 被引量:1
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作者 Dehai LUO Wenqi ZHANG Binhe LUO 《Advances in Atmospheric Sciences》 2025年第10期2018-2035,共18页
A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and... A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and development of the NMI model and then emphasize that the NMI model represents a new tool for identifying the basic physics of how climate change influences mid-to-high latitude weather extremes.The building of the NMI model took place over three main periods.In the 1990s,a nonlinear Schr?dinger(NLS)equation model was presented to describe atmospheric blocking as a wave packet;however,it could not depict the lifetime(10-20 days)of atmospheric blocking.In the 2000s,we proposed an NMI model of atmospheric blocking in a uniform basic flow by making a scale-separation assumption and deriving an eddyforced NLS equation.This model succeeded in describing the life cycle of atmospheric blocking.In the 2020s,the NMI model was extended to include the impact of a changing climate mainly by altering the basic zonal winds and the magnitude of the meridional background potential vorticity gradient(PVy).Model results show that when PVy is smaller,blocking has a weaker dispersion and a stronger nonlinearity,so blocking can be more persistent and have a larger zonal scale and weaker eastward movement,thus favoring stronger weather extremes.However,when PVy is much smaller and below a critical threshold under much stronger winter Arctic warming of global warming,atmospheric blocking becomes locally less persistent and shows a much stronger westward movement,which acts to inhibit local cold extremes.Such a case does not happen in summer under global warming because PVy fails to fall below the critical threshold.Thus,our theory indicates that global warming can render summer-blocking anticyclones and mid-to-high latitude heatwaves more persistent,intense,and widespread. 展开更多
关键词 nonlinear Schrödinger equation nonlinear multi-scale interaction model of atmospheric blocking meridional background potential vorticity gradient climate change mid-to-high latitude weather extremes
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Effect of the Blocking High-East Asian Trough on Three Extreme Cold Events in Eastern Asia
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作者 Ziqun ZHANG Hongyan CUI +4 位作者 Fangli QIAO Baoxu CHEN Yang SONG Xiaohui SUN Chang GAO 《Advances in Atmospheric Sciences》 2025年第5期892-903,共12页
Three extreme cold events occurred in eastern Asia in January 2016,January 2021,and December 2023.As important factors in atmospheric circulation anomalies,the Blocking High and East Asian Trough(BH-ET)structure playe... Three extreme cold events occurred in eastern Asia in January 2016,January 2021,and December 2023.As important factors in atmospheric circulation anomalies,the Blocking High and East Asian Trough(BH-ET)structure played key roles during these three extreme cold wave events.Among these two dynamic patterns,the BH affected the development of the cold waves in two different ways:(1)before the cold waves in 2016 and 2023,the BH pushed the cold air southward,resulting in a slow and gradual cooling,with a cooling rate(CR)in eastern Asia of 1.34℃d^(-1)and 1.2℃d^(-1),respectively,and(2)in January 2021,the sudden collapse of BH caused the cold air to rapidly attack mid-latitude regions,with a CR of 1.87℃d^(-1).In terms of the spatial CR,the temperature drop in 2021 occurred 38.8%and 55%faster than those in 2016 and 2023,respectively.At the same time,the ET influences the wind direction of cold waves by modulating the pressure gradient.Before the cold waves occurred,the meridional wind field near the ET showed negative values,forming northwesterly or northeasterly winds,which continued to affect the southern part of East Asia.The meridional wind in January 2021 was stronger than those in 2016 and 2023,which is thought to be the reason for the strength of the 2021 cold wave.Finally,results from the temperature Empirical Orthogonal Function(EOF)analysis from 1980-2023 verify an obvious BH-ET structure in the three cold wave events,which suggests that this particular climatological state provides a climatic background for the occurrence of cold waves. 展开更多
关键词 extreme cold waves blocking high East Asian trough cooling rate
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Chloride-Ion Blocking in Seawater Electrolysis:Narrating the Tale of Likes and Dislikes Between Anode and Ions
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作者 Ashish Gaur Enkhtuvshin Enkhbayar +2 位作者 Jatin Sharma Sungwook Mhin HyukSu Han 《Energy & Environmental Materials》 2025年第1期255-272,共18页
Seawater is the most abundant source of molecular hydrogen.Utilizing the hydrogen reserves present in the seawater may inaugurate innovative strategies aimed at advancing sustainable energy and environmental preservat... Seawater is the most abundant source of molecular hydrogen.Utilizing the hydrogen reserves present in the seawater may inaugurate innovative strategies aimed at advancing sustainable energy and environmental preservation endeavors in the future.Recently,there has been a surge in study in the field addressing the production of hydrogen through the electrochemical seawater splitting.However,the performance and durability of the electrode have limitations due to the fact that there are a few challenges that need to be addressed in order to make the technology suitable for the industrial purpose.The active site blockage caused by chloride ions that are prevalent in seawater and chloride corrosion is the most significant issue;it has a negative impact on both the activity and the durability of the anode component.Addressing this particular issue is of upmost importance in the seawater splitting area.This review concentrates on the newly developed materials and techniques for inhibiting chloride ions by blocking the active sites,simultaneously preventing the chloride corrosion.It is anticipated that the concept will be advantageous for a large audience and will inspire researchers to study on this particular area of concern. 展开更多
关键词 chloride ion blocking ELECTROCATALYSIS Lewis acid oxygen evolution reaction seawater electrolysis
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High quantum yield yellow emission carbon dots for the construction of blue light blocking films
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作者 Liwen Wang Boyang Wang +2 位作者 Siyu Lu Shubo Lv Xiaoli Qu 《Chinese Chemical Letters》 2025年第2期216-221,共6页
White light illumination is essential in daily life,however,the substantial amount of blue light it contains can damage human eyes.Therefore,it is important to block this high-energy blue light to protect visual healt... White light illumination is essential in daily life,however,the substantial amount of blue light it contains can damage human eyes.Therefore,it is important to block this high-energy blue light to protect visual health.In this study,yellow-emitting carbon dots(CDs)with a quantum yield exceeding 94%were synthesized using citric acid and urea.These CDs effectively absorb blue light.By incorporating them into polystyrene,multiple films termed CDs-based blue light blocking films(CBFs)were developed,each offering different levels of blue light absorption.These CBFs exhibited excellent transparency and efficient blue light filtering capabilities.This study highlights the potential of high quantum yield CDs,which specifically absorb blue light,as foundational materials for developing light-blocking solutions against highenergy short-wavelength light. 展开更多
关键词 Carbon dots High quantum yield Controllable preparation Blue light blocking Composite film
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Deep Reinforcement Learning-based Multi-Objective Scheduling for Distributed Heterogeneous Hybrid Flow Shops with Blocking Constraints
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作者 Xueyan Sun Weiming Shen +3 位作者 Jiaxin Fan Birgit Vogel-Heuser Fandi Bi Chunjiang Zhang 《Engineering》 2025年第3期278-291,共14页
This paper investigates a distributed heterogeneous hybrid blocking flow-shop scheduling problem(DHHBFSP)designed to minimize the total tardiness and total energy consumption simultaneously,and proposes an improved pr... This paper investigates a distributed heterogeneous hybrid blocking flow-shop scheduling problem(DHHBFSP)designed to minimize the total tardiness and total energy consumption simultaneously,and proposes an improved proximal policy optimization(IPPO)method to make real-time decisions for the DHHBFSP.A multi-objective Markov decision process is modeled for the DHHBFSP,where the reward function is represented by a vector with dynamic weights instead of the common objectiverelated scalar value.A factory agent(FA)is formulated for each factory to select unscheduled jobs and is trained by the proposed IPPO to improve the decision quality.Multiple FAs work asynchronously to allocate jobs that arrive randomly at the shop.A two-stage training strategy is introduced in the IPPO,which learns from both single-and dual-policy data for better data utilization.The proposed IPPO is tested on randomly generated instances and compared with variants of the basic proximal policy optimization(PPO),dispatch rules,multi-objective metaheuristics,and multi-agent reinforcement learning methods.Extensive experimental results suggest that the proposed strategies offer significant improvements to the basic PPO,and the proposed IPPO outperforms the state-of-the-art scheduling methods in both convergence and solution quality. 展开更多
关键词 Multi-objective Markov decision process Multi-agent deep reinforcement learning Proximal policy optimization Distributed hybrid flow-shop scheduling blocking constraints
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Impact of proning with and without inhaled pulmonary vasodilators and neuromuscular blocking agents in COVID acute respiratory distress syndrome
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作者 Matthew Cabrera Sarika Bharil +2 位作者 Meghan Chin Seife Yohannes Paul Clark 《World Journal of Critical Care Medicine》 2025年第3期192-206,共15页
BACKGROUND A major cause of mortality in the coronavirus disease 2019(COVID-19)pandemic was acute respiratory distress syndrome(ARDS).Currently,moderate to severe ARDS induced by COVID-19(COVID ARDS)and other viral an... BACKGROUND A major cause of mortality in the coronavirus disease 2019(COVID-19)pandemic was acute respiratory distress syndrome(ARDS).Currently,moderate to severe ARDS induced by COVID-19(COVID ARDS)and other viral and non-viral etiologies are treated by traditional ARDS protocols that recommend 12-16 hours of prone position ventilation(PPV)with neuromuscular blocking agents(NMBA)and a trial of inhaled vasodilators(IVd)if oxygenation does not improve.However,debate on the efficacy of adjuncts to PPV and low tidal volume ventilation persists and evidence about the benefits of IVd/NMBA in COVID ARDS is sparse.In our multi-center retrospective review,we evaluated the impact of PPV,IVd,and NMBA on outcomes and lung mechanics in COVID ARDS patients with moderate to severe ARDS.AIM To evaluate the impact of PPV used alone or in combination with pulmonary IVd and/or NMBA in mechanically ventilated patients with moderate to severe ARDS during the COVID-19 pandemic.METHODS A retrospective study at two tertiary academic medical centers compared outcomes between COVID ARDS patients receiving PPV and patients in the supine position.PPV patients were divided based on concurrent use of ARDS adjunct therapies resulting in four subgroups:(1)PPV alone;(2)PPV and IVd;(3)PPV and NMBA;and(4)PPV,IVd,and NMBA.Primary outcomes were hospital and intensive care unit(ICU)length of stay(LOS),mortality,and venovenous extracorporeal membrane oxygenation(VV-ECMO)status.Secondary outcomes included changes in lung mechanics at 24-hour intervals for 7 days.RESULTS Total 114 patients were included in this study.Baseline respiratory parameters and Sequential Organ Failure Assessment scores were significantly worse in the PPV group.ICU LOS and LOS were significantly longer for patients who were proned,but no mortality benefit or difference in VV-ECMO status was found.Among the subgroups,no difference in primary outcomes were found.In the secondary analysis,PPV was associated with a significant improvement in arterial oxygen partial pressure(PaO_(2))/fractional inspired oxygen(FiO_(2))(P/F)ratio from day 1 to day 4(P<0.05)and higher driving pressures day 5 to day 7(P<0.05).The combination of PPV and IVd together resulted in improvements in P/F ratio from day 1 to day 7 and plateau pressure on day 4 and day 6(P<0.05).PPV with NMBA was not associated with improvements in any of the secondary outcomes.The use of all three rescue therapies together resulted in improvements in lung compliance on day 2(P<0.05)but no other improvements.CONCLUSION In mechanically ventilated patients diagnosed with moderate to severe COVID ARDS,PPV and PPV with the addition of IVd produced a significant and sustained increase in P/F ratio.The combination of PPV,IVd and NMBA improved compliance however this did not reach significance.Mortality and LOS did not improve with adjunct therapies.Further research is warranted to determine the efficacy of these therapies alone and in combination in the treatment of COVID ARDS. 展开更多
关键词 Acute respiratory distress syndrome COVID Prone position ventilation Neuromuscular blocking agents Pulmonary vasodilators Mechanical ventilation Plateau pressure Driving pressure Peak end expiratory pressure
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Greatly enhanced corrosion/wear resistances of epoxy coating for Mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer 被引量:2
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作者 Z.Y.Xue X.J.Li +3 位作者 J.H.Chu M.M.Li D.N.Zou L.B.Tong 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期332-344,共13页
The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various industries.The conventional epoxy coating easily forms many intrinsic defects during the solidification proc... The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various industries.The conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient protection.In the current study,we design a double-layer epoxy composite coating on Mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly technique.The outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)film.The FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier capability.The Ce film connects the outer layer with the substrate,showing the transition effect.The corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling behavior.The synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloys. 展开更多
关键词 Mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance blocking layer
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CRB:A new rumor blocking algorithm in online social networks based on competitive spreading model and influence maximization 被引量:1
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作者 董晨 徐桂琼 孟蕾 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期588-604,共17页
The virtuality and openness of online social platforms make networks a hotbed for the rapid propagation of various rumors.In order to block the outbreak of rumor,one of the most effective containment measures is sprea... The virtuality and openness of online social platforms make networks a hotbed for the rapid propagation of various rumors.In order to block the outbreak of rumor,one of the most effective containment measures is spreading positive information to counterbalance the diffusion of rumor.The spreading mechanism of rumors and effective suppression strategies are significant and challenging research issues.Firstly,in order to simulate the dissemination of multiple types of information,we propose a competitive linear threshold model with state transition(CLTST)to describe the spreading process of rumor and anti-rumor in the same network.Subsequently,we put forward a community-based rumor blocking(CRB)algorithm based on influence maximization theory in social networks.Its crucial step is to identify a set of influential seeds that propagate anti-rumor information to other nodes,which includes community detection,selection of candidate anti-rumor seeds and generation of anti-rumor seed set.Under the CLTST model,the CRB algorithm has been compared with six state-of-the-art algorithms on nine online social networks to verify the performance.Experimental results show that the proposed model can better reflect the process of rumor propagation,and review the propagation mechanism of rumor and anti-rumor in online social networks.Moreover,the proposed CRB algorithm has better performance in weakening the rumor dissemination ability,which can select anti-rumor seeds in networks more accurately and achieve better performance in influence spread,sensitivity analysis,seeds distribution and running time. 展开更多
关键词 online social networks rumor blocking competitive linear threshold model influence maximization
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改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形效果评价
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作者 卢春燕 崔雪蕾 曹培培 《上海口腔医学》 2025年第2期152-156,共5页
目的:探讨改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形的效果。方法:回顾性分析2018年1月—2022年1月如皋市中医院收治的96例安氏Ⅱ类1分类错[牙合]畸形患者资料,根据治疗方法分为试验组(52例)和对照组(44例),... 目的:探讨改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形的效果。方法:回顾性分析2018年1月—2022年1月如皋市中医院收治的96例安氏Ⅱ类1分类错[牙合]畸形患者资料,根据治疗方法分为试验组(52例)和对照组(44例),对照组采用改良Twin-block矫治器,试验组采用改良Twin-block矫治器联合微种植体支抗。比较2组矫治时间、咬合打开时间、排列整齐时间、上下牙槽座角(ANB)、下牙槽座角(SNB)、上牙槽座角(SNA)、上中切牙长轴与NA连线的夹角(U1-NA)、下中切牙长轴与NA连线的夹角(U1-NB)、上颌中切牙长轴与前颅底平面夹角(U1-SN)、下颌中切牙长轴与下颌平面的后上交角(L1-MP)、上颌唇突度(ULP)、下颌唇突度(LLP)、上下唇突点与颏前点切线和眼耳平面夹角(Z角)、菌斑指数(PLI)、牙龈指数(GI)和龈沟出血指数(SBI)。记录并发症及患者满意度。采用SPSS 24.0软件包对数据进行统计学分析。结果:试验组患者矫治时间、咬合打开时间及排列整齐时间显著少于对照组(P<0.05)。治疗后,2组ANB、U1-NA和U1-SN小于治疗前,试验组显著小于对照组(P<0.05);U1-NB、L1-MP大于治疗前,试验组显著大于对照组(P<0.05);SNB、SNA相比无显著差异(P>0.05)。治疗后,2组ULP、LLP低于治疗前,试验组显著低于对照组(P<0.05);Z角升高,试验组显著高于对照组(P<0.05);PLI低于治疗前,试验组显著低于对照组(P<0.05);GI、SBI相比无显著差异(P>0.05)。2组患者满意度相比无显著差异(P>0.05)。结论:改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形,有助于缩短矫治时间,改善颌骨及面部软组织轮廓,促进牙美学效果的恢复。 展开更多
关键词 错[牙合]畸形 安氏Ⅱ类1分类错[牙合] 改良Twin-block矫治器 微种植体支抗
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A nanobody-based blocking enzyme-linked immunosorbent assay for detecting antibodies against pseudorabies virus glycoprotein E
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作者 Huanhuan Lü Pinpin Ji +6 位作者 Siyu Liu Ziwei Zhang Lei Wang Yani Sun Baoyuan Liu Lizhen Wang Qin Zhao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1354-1368,共15页
Pseudorabies(PR)is an acute infectious disease of pigs caused by the PR virus(PRV)and results in great economic losses to the pig industry worldwide.PRV glycoprotein E(gE)-based enzyme-linked immunosorbent assay(ELISA... Pseudorabies(PR)is an acute infectious disease of pigs caused by the PR virus(PRV)and results in great economic losses to the pig industry worldwide.PRV glycoprotein E(gE)-based enzyme-linked immunosorbent assay(ELISA)has been used to distinguish gE-deleted vaccine-immunized pigs from wild-type virus-infected pigs to eradicate PR in some countries.Nanobody has the advantages of small size and easy genetic engineering and has been a promising diagnostic reagent.However,there were few reports about developing nanobody-based ELISA for detecting anti-PRV-gE antibodies.In the present study,the recombinant PRV-gE was expressed with a bacterial system and used to immunize the Bactrian camel.Then,two nanobodies against PRV-gE were screened from the immunized camel by phage display technique.Subsequently,two nanobody-HRP fusion proteins were expressed with HEK293T cells.The PRV-gE-Nb36-HRP fusion protein was selected as the probe for developing the blocking ELISA(bELISA)to detect anti-PRV-gE antibodies.Through optimizing the conditions of bELISA,the amount of coated antigen was 200 ng per well,and dilutions of the fusion protein and tested pig sera were separately 1:320 and 1:5.The cut-off value of bELISA was 24.20%,and the sensitivity and specificity were 96.43 and 92.63%,respectively.By detecting 233 clinical pig sera with the developed bELISA and a commercial kit,the results showed that the coincidence rate of two assays was 93.99%.Additionallly,epitope mapping showed that PRV-gE-Nb36 recognized a conserved conformational epitope in different reference PRV strains.Simple,great stability and low-cost nanobody-based bELISA for detecting anti-PRV-gE antibodies were developed.The bELISA could be used for monitoring and eradicating PR. 展开更多
关键词 NANOBODY nanobody-HRP blocking ELISA PRV-gE ANTIBODY
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COX-2 blocking therapy in cisplatin chemosensitization of ovarian cancer:An allicin-based nanomedicine approach
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作者 Huijiao Fu Peiqin Liang +8 位作者 Qianwen Chen Yan Wang Guang Li Xuzi Cai Shengtao Wang Kun Chen Shengying Shi Zhiqiang Yu Xuefeng Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第8期449-454,共6页
Recently,the utilization of nonsteroidal anti-inflammatory drugs(NSAIDs)to sensitize cisplatin(CDDP)has gained substantial traction in the treatment of ovarian cancer(OC).However,even widely employed NSAIDs such as ce... Recently,the utilization of nonsteroidal anti-inflammatory drugs(NSAIDs)to sensitize cisplatin(CDDP)has gained substantial traction in the treatment of ovarian cancer(OC).However,even widely employed NSAIDs such as celecoxib and naproxen carry an elevated risk of cardiovascular events,notably throm-bosis.Furthermore,the diminished sensitivity to CDDP therapy in OC is multifactorial,rendering the ap-plication of NSAIDs only partially effective due to their cyclooxygenase-2(COX-2)inhibiting mechanism.Hence,in this study,reactive oxygen species(ROS)-responsive composite nano-hydrangeas loaded with the Chinese medicine small molecule allicin and platinum(IV)prodrug(DTP@AP NPs)were prepared to achieve comprehensive chemosensitization.On one front,allicin achieved COX-2 blocking therapy,en-compassing the inhibition of proliferation,angiogenesis and endothelial mesenchymal transition(EMT),thereby mitigating the adverse impacts of CDDP chemotherapy.Simultaneously,synergistic chemosensi-tization was achieved from multifaceted mechanisms by decreasing CDDP inactivation,damaging mito-chondria and inhibiting DNA repair.In essence,these findings provided an optimized approach for syner-gizing CDDP with COX-2 inhibitors,offering a promising avenue for enhancing OC treatment outcomes. 展开更多
关键词 COX-2 blocking therapy CDDP CHEMOSENSITIZATION ALLICIN Ovarian cancer
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Development and performance evaluation of high temperature resistant strong adsorption rigid blocking agent
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作者 Zhe Xu Jin-Sheng Sun +6 位作者 Jing-Ping Liu Kai-He Lv Xiao-Dong Dong Zong-Lun Wang Tai-Feng Zhang Yuan-Wei Sun Zhi-Wen Dai 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2650-2662,共13页
As drilling wells continue to move into deep ultra-deep layers,the requirements for temperature resistance of drilling fluid treatments are getting higher and higher.Among them,blocking agent,as one of the key treatme... As drilling wells continue to move into deep ultra-deep layers,the requirements for temperature resistance of drilling fluid treatments are getting higher and higher.Among them,blocking agent,as one of the key treatment agents,has also become a hot spot of research.In this study,a high temperature resistant strong adsorption rigid blocking agent(QW-1)was prepared using KH570 modified silica,acrylamide(AM)and allyltrimethylammonium chloride(TMAAC).QW-1 has good thermal stability,average particle size of 1.46μm,water contact angle of 10.5.,has a strong hydrophilicity,can be well dispersed in water.The experimental results showed that when 2 wt%QW-1 was added to recipe A(4 wt%bentonite slurry+0.5 wt%DSP-1(filtration loss depressant)),the API filtration loss decreased from 7.8to 6.4 m L.After aging at 240.C,the API loss of filtration was reduced from 21 to 14 m L,which has certain performance of high temperature loss of filtration.At the same time,it is effective in sealing 80-100mesh and 100-120 mesh sand beds as well as 3 and 5μm ceramic sand discs.Under the same conditions,the blocking performance was superior to silica(5μm)and calcium carbonate(2.6μm).In addition,the mechanism of action of QW-1 was further investigated.The results show that QW-1 with amide and quaternary ammonium groups on the molecular chain can be adsorbed onto the surface of clay particles through hydrogen bonding and electrostatic interaction to form a dense blocking layer,thus preventing further intrusion of drilling fluid into the formation. 展开更多
关键词 High adsorption Rigid microsphere High temperature resistance blocking performance
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Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果比较
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作者 黄飞 陈倩 张胜男 《中国现代医学杂志》 2025年第6期6-11,共6页
目的对比Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果。方法选取2020年2月—2022年5月在彭州市中医医院就诊的安氏Ⅱ类1分类错[牙合]畸形患者72例,采用随机数字表法将其分成研究组和对照组,... 目的对比Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果。方法选取2020年2月—2022年5月在彭州市中医医院就诊的安氏Ⅱ类1分类错[牙合]畸形患者72例,采用随机数字表法将其分成研究组和对照组,每组36例。对照组接受Twin-block功能矫治器联合自锁托槽治疗,研究组接受Pass矫治器治疗。对比两组临床疗效、颌牙排齐时间、硬组织头影测量指标[上中切牙轴与蝶鞍中心-鼻根点平面夹角(U1-SN)、下中切牙轴与鼻根点-上齿槽座点连接角(U1-NA)、上齿槽座点、鼻根点及下次槽座点连接角(ANB)、蝶鞍中心、鼻根点及上齿槽座点连接角(SNA)]、软组织头影测量目标[上唇到审美平面距离(TUL-FP)、下唇H线距、下唇到审美平面距离(TLL-FP)、鼻唇角]、矫治效果及患者满意度。结果研究组总有效率高于对照组(P<0.05)。研究组上颌牙排齐时间和下颌牙排齐时间均短于对照组(P<0.05)。两组治疗前后U1-SN、ANB、SNA、SNB的差值比较,差异无统计学意义(P>0.05)。研究组治疗前后U1-NA的差值高于对照组(P<0.05)。研究组治疗前后下唇H线距、TUL-FP、鼻唇角、TLL-FP的差值高于对照组(P<0.05)。研究组治疗前后同行评估等级指数(PAR)评分的差值高于对照组(P<0.05)。研究组满意度高于对照组(P<0.05)。结论相比于Twin-block功能矫治器联合自锁托槽,Pass矫治器治疗安氏Ⅱ类1分类错[牙合]畸形患者效果确切,可提高矫治效果,改善面部侧貌美学,缩短颌牙排齐时间,且患者满意度较高。 展开更多
关键词 安氏Ⅱ类1分类错[牙合]畸形 Pass矫治器 TWIN-block功能矫治器 自锁托槽 矫正效果
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安氏Ⅱ类错[牙合]畸形佩戴Twin-block矫治器时上颌骨的应力分布 被引量:1
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作者 李帅 刘桦 +3 位作者 商永慧 刘义琮 赵启航 刘文 《中国组织工程研究》 CAS 北大核心 2025年第5期881-887,共7页
背景:Twin-block矫治器常用于安氏Ⅱ类错[牙合]畸形的矫治,其刺激下颌骨生长的作用机制已得到许多研究证实,但对上颌骨生长的影响尚不清楚。目的:通过有限元法分析安氏Ⅱ类错[牙合]畸形患者佩戴Twin-block矫治器时上颌骨复合体、周围骨... 背景:Twin-block矫治器常用于安氏Ⅱ类错[牙合]畸形的矫治,其刺激下颌骨生长的作用机制已得到许多研究证实,但对上颌骨生长的影响尚不清楚。目的:通过有限元法分析安氏Ⅱ类错[牙合]畸形患者佩戴Twin-block矫治器时上颌骨复合体、周围骨缝及上颌牙列的应力分布。方法:选择在山东省康复大学青岛医院/青岛市市立医院口腔正畸科进行正畸治疗的安氏Ⅱ类错[牙合]畸形患者1例,测量患者佩戴Twin-block矫治器时的咬合力数据,采集其锥形束CT数据,建立包含上颌骨复合体、周边各骨缝、Twin-block矫治器及上颌牙列在内的有限元模型,通过ABAQUS软件模拟患者戴入Twin-block时上颌骨、骨缝及上颌牙列的应力分布与位移。结果与结论:①上颌前牙受到的等效应力明显小于后牙,两侧牙齿的最大等效应力分别为4.7975 MPa和8.7161 MPa,均位于第一前磨牙处;最大位移呈现在两侧上颌切牙处,分别为0.0805 mm和0.0810 mm;②骨缝的最大等效应力为1.284 MPa,主要集中在两侧翼腭缝及额颌缝,其余骨缝受力情况几乎无差异;骨缝的最大位移为0.07 mm,其中翼腭缝的位移量最大,其次是额颌缝;③上颌骨复合体受到的最大等效应力为27.18 MPa,主要集中在上颌骨前面梨状孔两侧、鼻额缝周边及颚骨后部翼腭缝附近;上颌骨的最大位移值为0.07 mm,主要集中于上颌牙槽骨;④结果显示,咬合力通过Twin-block矫治器作用于上颌骨复合体,导致上颌骨顺时针旋转、牙合平面变陡,应采取相应措施补偿这种趋势,例如建牙合过程中考虑上颌磨牙伸长、下颌磨牙压低,不仅能够将牙合平面整平,同时有利于下颌前伸,这将进一步提高Ⅱ类错[牙合]正畸治疗效果。 展开更多
关键词 错牙合畸形 组织构建 骨组织工程 TWIN-block矫治器 功能矫治 有限元分析
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3种不同类型Twin-block矫治器对前牙应力分布和位移的影响
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作者 李星雨 张春艳 +8 位作者 李希贝 黄文莉 于少洋 杨文科 张映玥 郭骏 阎潇 张强 袁晓 《医用生物力学》 北大核心 2025年第4期844-850,共7页
目的 研究3种不同类型Twin-block矫治器对前牙、牙周膜及牙槽骨应力及位移的影响。方法 构建上下颌骨、关节盘、牙列及牙周膜的三维有限元模型。3组不同类型Twin-block矫治器的有限元模型分别为传统Twin-block矫治器、带切牙帽Twin-bloc... 目的 研究3种不同类型Twin-block矫治器对前牙、牙周膜及牙槽骨应力及位移的影响。方法 构建上下颌骨、关节盘、牙列及牙周膜的三维有限元模型。3组不同类型Twin-block矫治器的有限元模型分别为传统Twin-block矫治器、带切牙帽Twin-block矫治器、改良隐形Twin-block矫治器(clear twin-block aligner, CTBA)。所有类型矫治器的斜面角度均为70°,双侧分别加载200 N垂直于斜面的力。利用有限元方法分析前牙的应力分布与位移差异。结果 3种不同类型Twin-block矫治器均会导致上前牙舌倾及下前牙唇倾。CTBA组上前牙舌向位移及应力最大,最大应力为30.6 MPa,而下前牙唇向位移及应力最小,位移约为0.02 mm。同时CTBA组下前牙、牙周膜及牙槽骨所受等效应力在3组中最低,而传统Twin-block矫治器组最高。结论 在使用传统Twin-block矫治器治疗安氏Ⅱ类错[牙合]时,无论有无切牙帽,均会导致下前牙的唇倾;而与传统Twin-block矫治器相比,CTBA可减少对下前牙、牙槽骨、牙周膜应力和位移的影响,进而减小下前牙的牙周风险,但需注意上前牙舌向位移带来的舌倾效应。 展开更多
关键词 TWIN-block矫治器 功能矫治 隐形矫治器 安氏Ⅱ类错[牙合] 前牙
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Enhancing postoperative pain control by surgically-initiated rectus sheath block in abdominal aortic aneurysm open repair: A case report
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作者 Kuan-Hua Chen Ming-Yuan Kang +2 位作者 Yi-Ting Chang Sheng-Yang Huang Yung-Szu Wu 《World Journal of Clinical Cases》 SCIE 2025年第6期41-47,共7页
BACKGROUND Abdominal aortic aneurysm(AAA)repair often involves significant postoperative pain,traditionally managed with systemic opioids,which can cause undesirable side effects.This case report explores the novel us... BACKGROUND Abdominal aortic aneurysm(AAA)repair often involves significant postoperative pain,traditionally managed with systemic opioids,which can cause undesirable side effects.This case report explores the novel use of a surgically-initiated rectus sheath block with a catheter-over-needle assembly for pain management in AAA repair.CASE SUMMARY A 67-year-old female with hypertension and previous aortic dissection underwent elective open repair of an infrarenal AAA,which had grown from 3.4 cm to 4.3 cm over 14 months.A rectus sheath block was initiated surgically for postoperative pain control.The patient reported low pain scores and did not require systemic intravenous opioids,enabling early ambulation and discharge on postoperative day seven without complications.By preventing complications of systemic opi-oids,the method indicating a promising direction for postoperative pain management in major vascular surgeries.CONCLUSION Surgically-initiated rectus sheath block as a valuable tool for managing postoperative pain in AAA repair. 展开更多
关键词 Abdominal aortic aneurysm Postoperative pain management Rectus sheath block Surgical anesthesia Opioid-sparing techniques Case report
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The A_(α)-spectral Radius of Block Graphs with Given Dissociation Number
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作者 HUANG Peng LI Jianxi 《数学进展》 北大核心 2025年第4期696-708,共13页
For a simple graph G,let A(G)and D(G)be the adjacency matrix and the diagonal degree matrix of G,respectively.[Appl.Anal.Discrete Math.,2017,11(1):81-107]defined the matrix A_(α)(G)of G as A_(α)(G)=αD(G)(1-α)A(G)... For a simple graph G,let A(G)and D(G)be the adjacency matrix and the diagonal degree matrix of G,respectively.[Appl.Anal.Discrete Math.,2017,11(1):81-107]defined the matrix A_(α)(G)of G as A_(α)(G)=αD(G)(1-α)A(G),α∈[0,1].The Aa-spectral radius is the largest eigenvalue of A_(α)(G).Let G_(n,β) be the set graphs with order n and dissociation numberβ.In this paper,we identify the b with maximal A_(α)-spectral radius among all graphs in G_(n,β). 展开更多
关键词 A_(α)-spectral radius block graph SIZE dissociation number
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Block sparse compressed sensing with frames:Null space property and l_(2)/l_(q)(0
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作者 WU Fengong ZHONG Penghong QIN Yuehai 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第3期173-182,共10页
This paper explores the recovery of block sparse signals in frame-based settings using the l_(2)/l_(q)-synthesis technique(0<q≤1).We propose a new null space property,referred to as block D-NSP_(q),which is based ... This paper explores the recovery of block sparse signals in frame-based settings using the l_(2)/l_(q)-synthesis technique(0<q≤1).We propose a new null space property,referred to as block D-NSP_(q),which is based on the dictionary D.We establish that matrices adhering to the block D-NSP_(q)condition are both necessary and sufficient for the exact recovery of block sparse signals via l_(2)/l_(q)-synthesis.Additionally,this condition is essential for the stable recovery of signals that are block-compressible with respect to D.This D-NSP_(q)property is identified as the first complete condition for successful signal recovery using l_(2)/l_(q)-synthesis.Furthermore,we assess the theoretical efficacy of the l2/lq-synthesis method under conditions of measurement noise. 展开更多
关键词 Compressed sensing block sparse l2/lq-synthesis method null space property
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Clinical Nursing Intervention of Moxibustion on Abdominal Distension Symptoms in Heart Failure (Heart and Kidney Yang Deficiency and Blood Stasis Blocking Collaterals Syndrome)
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作者 Tingcui Yan 《Journal of Clinical and Nursing Research》 2024年第6期142-147,共6页
Objective:To investigate the clinical nursing intervention effect of moxibustion on abdominal distension symptoms in heart failure(heart and kidney yang deficiency and blood stasis blocking collaterals syndrome).Metho... Objective:To investigate the clinical nursing intervention effect of moxibustion on abdominal distension symptoms in heart failure(heart and kidney yang deficiency and blood stasis blocking collaterals syndrome).Methods:62 patients with heart failure(heart and kidney yang deficiency and blood stasis blocking collaterals syndrome)admitted to our hospital from February 2023 to February 2024 were selected and divided into the observation group(n=31)and the control group(n=31)by using the random numerical table method.The control group adopted conventional nursing interventions,and the observation group received the nursing program of the control group with the addition of moxibustion nursing interventions.The nursing effectiveness,quality of life scores,and nursing satisfaction were compared between the two groups.Results:The nursing effectiveness of the observation group was significantly higher than the control group(P<0.05);the quality of life score of the observation group was significantly higher than the control group(P<0.05);the nursing satisfaction of the observation group was significantly higher than that of the control group(P<0.05).Conclusion:The use of moxibustion nursing intervention in patients with heart failure(heart and kidney yang deficiency and blood stasis blocking collaterals syndrome)can effectively relieve the symptoms of abdominal distension,improve patients'quality of life,and increase nursing satisfaction,which has promotion and application values. 展开更多
关键词 MOXIBUSTION Heart failure Heart and kidney yang deficiency and blood stasis blocking collaterals syndrome Abdominal distension Nursing intervention
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Differential-Linear Attacks on Ballet Block Cipher
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作者 ZHOU Yu CHEN Si-Wei +2 位作者 XU Sheng-Yuan XIANG Ze-Jun ZENG Xiang-Yong 《密码学报(中英文)》 北大核心 2025年第2期469-488,共20页
Ballet is one of the finalists of the block cipher project in the 2019 National Cryptographic Algorithm Design Competition.This study aims to conduct a comprehensive security evaluation of Ballet from the perspective ... Ballet is one of the finalists of the block cipher project in the 2019 National Cryptographic Algorithm Design Competition.This study aims to conduct a comprehensive security evaluation of Ballet from the perspective of differential-linear(DL)cryptanalysis.Specifically,we present an automated search for the DL distinguishers of Ballet based on MILP/MIQCP.For the versions with block sizes of 128 and 256 bits,we obtain 16 and 22 rounds distinguishers with estimated correlations of 2^(-59.89)and 2^(-116.80),both of which are the publicly longest distinguishers.In addition,this study incorporates the complexity information of key-recovery attacks into the automated model,to search for the optimal key-recovery attack structures based on DL distinguishers.As a result,we mount the key-recovery attacks on 16-round Ballet-128/128,17-round Ballet-128/256,and 21-round Ballet-256/256.The data/time complexities for these attacks are 2^(108.36)/2^(120.36),2^(115.90)/2^(192),and 2^(227.62)/2^(240.67),respectively. 展开更多
关键词 Ballet block cipher differential-linear(DL)cryptanalysis MILP/MIQCP distinguisher key-recovery attacks
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