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herbst矫治器伴头帽牵引治疗安氏Ⅱ类错

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华西口腔医学杂志 2004年第1期22卷 46-48,51页

作者：杜熹 urban hgg 四川大学华西口腔医院正畸科四川成都610041 香港大学牙学院正畸专业

目的　研究herbst矫治器伴头帽牵引逐步前伸下颌对安氏Ⅱ类错的矫治效果。方法　治疗组 2 2例患者 ,对照组 31例患者。治疗组患者均按治疗的前 6个月、后 6个月 (平均 )及维持期 6个月 ,3个阶段治疗并拍摄头侧位定位片观察。对照组患... 详细信息

目的　研究herbst矫治器伴头帽牵引逐步前伸下颌对安氏Ⅱ类错的矫治效果。方法　治疗组 2 2例患者 ,对照组 31例患者。治疗组患者均按治疗的前 6个月、后 6个月 (平均 )及维持期 6个月 ,3个阶段治疗并拍摄头侧位定位片观察。对照组患者拍摄 2次头侧位定位片 ,其间间隔 6个月。结果　平均治疗 12个月后的疗效是抑制上颌骨生长、刺激下颌骨生长并降低下面高。与对照组相比 ,对上颌骨的抑制作用在治疗的前后 6个月均有统计学意义 ,对下颌骨的刺激作用仅在治疗前 6个月有统计学意义 ,对下面高的降低作用仅在治疗后 6个月有统计学意义。维持阶段上下基骨关系不变而对下面高的降低作用进一步加强。结论　herbst矫治器伴头帽牵引能有效地矫治安氏Ⅱ类错 ,对上颌骨的作用随时间的增加而加强。

关键词： herbst矫治器头帽牵引治疗安氏Ⅱ类错he 上颌骨

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人类健康牙齿近远中径双生子研究的系统评价

口腔医学研究 2014年第2期30卷 151-154页

作者：彭聪 Alexander Th Tang urban hgg 香港大学牙医学院深圳市第二人民医院口腔科香港大学牙医学院正畸科

目的:本研究通过系统性回顾分析相关双生子研究文献,了解基因对人类个别恒牙列中恒牙近远中径大小的贡献。方法:通过在PUBMED、OVID EMBASE、Cochrane Library以及CINAhL四个数据库最长时期的检索,检索部位为全文,关键词为"tooth size"+... 详细信息

目的:本研究通过系统性回顾分析相关双生子研究文献,了解基因对人类个别恒牙列中恒牙近远中径大小的贡献。方法:通过在PUBMED、OVID EMBASE、Cochrane Library以及CINAhL四个数据库最长时期的检索,检索部位为全文,关键词为"tooth size"+"genetics",或"tooth size"+"twin study"。检索结果的文献标题、关键词以及摘要都被仔细分析,通过排除标准以排除掉不相关的文献。整理出所得到的文献并通过阅读全文,查看它们所引用的参考文献,寻找可能被漏检的文献,汇总后再次通过另一次排除标准整理,进行总结和评价。结果:初次检索得到的435片文献中,首先排除掉8篇重复文献,剩余427篇。根据标题、关键词以及摘要,排除370篇,剩余57篇并获取全文,通过检视其所引用参考文献以寻找可能相关的文献75篇,合成为132篇文献。通过纳入标准排除,对最终留下的2篇文献进行评估基因对人类健康的恒牙列个别牙齿类型大小贡献的证据。结论:现有双生子研究数据表明,基因数据对下颌第二磨牙并不足够。其余所有类型恒牙牙齿大小,基因均存在贡献。

关键词：牙齿大小双生子研究基因

前方牵引器治疗安氏Ⅲ类错畸形—20例病例临床分析

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口腔正畸学 2000年第3期7卷 118-122页

作者：谷岩 A.Bakr M.Rabie urban hgg 北京大学口腔医学院正畸科 100081 香港大学牙医学院牙齿矫正科

目的　分析替牙期前方牵引器矫治安氏Ⅲ类错前牙反中骨性和牙性变化。方法　选择2 0例安氏Ⅲ类错前牙反患者 ,在替牙早期使用前方牵引器 ,治疗开始、治疗结束及治疗结束后一年拍摄头颇侧位片 ,并以Pancherz分析法进行头影测量... 详细信息

目的　分析替牙期前方牵引器矫治安氏Ⅲ类错前牙反中骨性和牙性变化。方法　选择2 0例安氏Ⅲ类错前牙反患者 ,在替牙早期使用前方牵引器 ,治疗开始、治疗结束及治疗结束后一年拍摄头颇侧位片 ,并以Pancherz分析法进行头影测量分析。结果　表明 ,在治疗刚刚结束时 ,覆盖增加 6 5毫米 ,其中 40 %为骨性变化 ,6 0 %为牙性代偿。治疗结束后一年发现覆盖减少 1 2毫米 ,即骨性变化占 2 3% ,牙性代偿 77%。

关键词：治疗前方牵引器代偿安氏Ⅲ类错he畸形前牙反he 下颌侧位片头影测量分析切牙病例

Cas13d-mediated gene knockdown in CAR T cells:towards off-the-shelf cancer treatment

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1796-1798页

作者： Midori Johnston Nadine urban Can Dincer FIT Freiburg Centre for Interactive Materials and Bioinspired Technology University of FreiburgFreiburgGermany IMTEK-Department of Microsystems Engineering University of FreiburgFreiburgGermany

In a recent study published in Cell,Tieu et *** RfxCas13d to dynamically enhance performance and longevity of chimeric antigen receptor(CAR)T cells by massively multiplexed gene knockdown and thereby,move the treatmen... 详细信息

关键词： treatment shelf

三种X线头影测量分析方法临床应用的比较研究

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上海口腔医学 2002年第2期11卷 97-100页

作者：游清玲 urban hgg 上海第二医科大学附属第九人民医院口腔医学院口腔正畸科上海200011 香港大学牙医学院矫正科

目的分析不同X线头影分析方法在正畸疗效分析中的作用。方法采用14例经herbst矫正器治疗的II类错牙合病例治疗前后的X线头影侧位片,用Bj觟rk、Ricketts和Pancherz3种分析方法分别对所有资料进行描绘分析,使用同一参考系统,定量评价矢状... 详细信息

目的分析不同X线头影分析方法在正畸疗效分析中的作用。方法采用14例经herbst矫正器治疗的II类错牙合病例治疗前后的X线头影侧位片,用Bj觟rk、Ricketts和Pancherz3种分析方法分别对所有资料进行描绘分析,使用同一参考系统,定量评价矢状面上发生的牙性和骨性变化。结果3种分析方法在统计学上都是可靠的;在评价矢状方向骨性和牙性变化上,3种方法间无显著差异;可靠性指数显示,3种分析方法均不适合于个体分析,只有Pancherz方法对群体分析有效。结论三种头影分析方法各有特点,Pancherz方法相对比较直观有效,且能进行定量分析。

关键词： Bjoerk分析法 Ricketts分析法 Pancherz分析法 X线头影定位分析口腔正畸学临床应用

Nano-enhanced solid-state hydrogen storage:Balancing discovery and pragmatism for future energy solutions

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Nano Research 2024年第10期17卷 8729-8753页

作者： Chaochao Dun Xinyi Wang Linfeng Chen Sichi Li hanna M.Breunig Jeffrey J.urban The Molecular Foundry Lawrence Berkeley National Laboratory BerkeleyBerkeleyCA 94720USA Energy Analysis and Environmental Impacts Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Lawrence Livermore National Laboratory LivermoreCA 94550USA

Nanomaterials have revolutionized the battery industry by enhancing energy storage capacities and charging speeds,and their application in hydrogen(h_(2))storage likewise holds strong potential,though with distinct challenges and mechanisms.h_(2) is a crucial future zero-carbon energy vector given its high gravimetric energy density,which far exceeds that of liquid ***,its low volumetric energy density in gaseous form currently requires storage under high pressure or at low *** review critically examines the current and prospective landscapes of solid-state h_(2) storage technologies,with a focus on pragmatic integration of advanced materials such as metal-organic frameworks(MOFs),magnesium-based hybrids,and novel sorbents into future energy *** materials,enhanced by nanotechnology,could significantly improve the efficiency and capacity of h_(2) storage systems by optimizing h_(2) adsorption at the nanoscale and improving the kinetics of h_(2) uptake and *** discuss various h_(2) storage mechanisms—physisorption,chemisorption,and the Kubas interaction—analyzing their impact on the energy efficiency and scalability of storage *** review also addresses the potential of“smart MOFs”,single-atom catalyst-doped metal hydrides,MXenes and entropy-driven alloys to enhance the performance and broaden the application range of h_(2) storage systems,stressing the need for innovative materials and system integration to satisfy future energy ***-throughput screening,combined with machine learning algorithms,is noted as a promising approach to identify patterns and predict the behavior of novel materials under various conditions,significantly reducing the time and cost associated with experimental *** closing,we discuss the increasing involvement of various companies in solid-state h_(2) storage,particularly in prototype vehicles,from a techno-economic *** forward-looking perspective underscores t

关键词： nanomaterials nanotechnology solid-state h_(2)storage techno-economic analysis model-driven material development processes

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.M.FEIZABAD M.h.YAS Department of Mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQM)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQM)

holographic dark energy in non-conserved gravity theory

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Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： h R Fazlollahi Institute of Gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

Recently, reconsidering the Rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~h^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy

Convexification of hybrid AC-DC Optimal Power Flow with Line-Commutated Converters

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 617-628页

作者： hongyuan Liang Zhigang Li J.h.Zheng Q.h.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

Line-commutated converter (LCC)-based high-voltage DC (hVDC) systems have been integrated with bulk AC power grids for interregional transmission of renewable power. The nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of hybrid AC-DC power grids. A convexification method for the LCC station model could address such nonconvexity but has rarely been discussed. We devise an equivalent reformulation for classical LCC station models that facilitates second-order cone convex relaxation for the OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with its proof. Equivalence of the proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of the original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming