Revision rhinoplasty for contracted nose:A systematic review and meta-analysis

Background:This study aimed to review treatments and evaluate the aesthetic outcomes,complications,and reoperation rates regarding surgical correction for a postoperative contracted nose.Methods:PubMed,MEDLINE,and Embase databases were searched for studies detailing aesthetic outcomes and complications of surgical correction of a contracted nose.Surgical procedures,adjuvant treatment,outcomes,and complications were synthesized and analyzed.Results:Nine articles encompassing 376 patients were included in the systematic review,and six articles(198 participants)were included in the meta-analysis.The most frequently used graft material was the autologous rib cartilage(61.1%).Surgical procedures were heterogeneous in these studies.The nasolabial angle reduced by 9.52°(95%confidence interval(CI):(-11.95,-7.09),P<0.0001),and the nasal length increased significantly(standardized mean difference(SMD)=2.25,95%CI:(1.26,2.23),P<0.00001).However,the evidence was insufficient to determine a significant change in the columellar-labial angle(SMD=-0.95,95%CI:(-2.19,0.29),P=0.13)and columellar-lobular angle(SMD=2.39,95%CI:(-1.20,5.97),P=0.19).Aesthetic dissatisfaction(12.5%)and infection(4.5%)were the most commonly reported complications.Reoperation was performed in 5.3%of patients.Conclusion:Surgical correction can increase the nasal length,reduce the nasolabial angle,and have a low reoperation rate.No significant improvement in the columellar-labial or columellar-lobular angle was observed.

A Structural Interpretation Model and Restoration of the Mesozoic Proto-basin for the Kuqa Depression,Tarim Basin

A thrust-fold belt consisting of a series of thrusts and buckling folds developed in the Mesozoic and Cenozoic strata within the Kuqa Depression,Tarim Basin.In this study,a structural interpretation model of the Kuqa Depression is established and the Mesozoic proto-basin is reconstructed on the basis of outcrop geology along the basin margin,seismic,well-log and CEMP data.The model is called‘delaminate contractional deformation',which emphasizes the decoupling between the Cenozoic,Mesozoic,pre-Mesozoic and the basin-basement within the Kuqa Depression,but there is no unified detachment.The model has a shortening amount ranging from 12 km to 16 km and the depth involved in contractional deformation ranges from 21 km to 28 km.A prototype of the Mesozoic basin reconstructed by interpretation model is a subbasin superposed on the transitional zone between the uplift at the northern edge of the Tarim Craton and the southern Tianshan orogenic wedge formed in the Hercynian orogeny.Lithospheric thermal and crustal isostatic activity after the Hercynian orogeny maybe the controlling dynamic factors of basin subsidence during the Mesozoic and early Cenozoic,the difference in rock mechanical properties between different levels,craton and orogenic wedge being the major cause of the‘delaminate contractional deformation'during the Himalayan orogeny.

北山东南部早白垩世伸展构造变形:二维反射地震剖面解释与磷灰石裂变径迹测年的制约

为深入认识中亚造山带南缘晚中生代陆内变形过程及其动力学机制,通过野外地质观察、二维反射地震剖面解释及磷灰石裂变径迹测年,对北山东南部早白垩世伸展构造及早期挤压构造进行了详细解析。结果表明,一系列逆冲断层与褶皱构造造成下—中侏罗统发生强烈的挤压变形。地震剖面揭示出2条早白垩世伸展正断层,其中梭梭井断层为南东倾向的低角度铲式正断层,五道明断层为北西倾向的高角度正断层,二者共同切割了早期形成的褶皱-冲断系统,指示挤压-伸展构造的转换;梭梭井断层与五道明断层分别限定了早白垩世总口子盆地的北西和南东边界,使得其具有“地堑”样式,盆地内沉积的下白垩统生长地层发育,表明伸展正断层的活动时间为早白垩世晚期。磷灰石裂变径迹热史模拟结果显示,梭梭井断层下盘于132~110 Ma经历了快速冷却和剥露事件,该事件与其持续的正断层活动密切相关,进一步证实北山东南部晚中生代挤压-伸展构造的转换很可能发生在早白垩世晚期(133~129 Ma)。增厚地壳的重力垮塌与局部地幔上涌共同导致了中亚造山带南缘早白垩世的区域伸展作用。

温度变化对孔、轴配合性质的影响

以设定的孔、轴配合为研究对象,在工作温度偏离标准设计温度20℃时,孔、轴的配合性质会发生变化。考虑原设计为间隙配合,随着温度的升高,配合性质逐渐变为过渡配合,严重时甚至变为过盈配合,直接影响工作性能,因此理论计算和有限元仿真都证明温度变化会影响孔、轴的配合性质。研究结果将为数控机床、加工中心的孔、轴配合以及热变形研究提供了依据。

干湿环境下膨胀土裂隙演化规律及渠坡变形研究

研究干湿循环效应下膨胀土裂隙发育规律对揭示膨胀土渠道边坡失稳机制有重要意义。针对目前研究中存在的不足,开展了仅考虑干湿循环效应的膨胀土裂隙演化试验,系统测量了随时间变化的水分蒸发过程及裂隙动态发育特征。基于膨胀土裂隙演化规律,通过编程将块体离散元方法应用至膨胀土渠坡变形分析中,并得到如下结论:(1)膨胀土水分蒸发过程可分为稳定蒸发阶段、减速率蒸发阶段和残余蒸发阶段;(2)随着干湿循环次数增加,膨胀土面积裂隙率逐渐增加后趋于稳定,裂隙总长度逐步增加,裂隙平均宽度不断减小并逐渐稳定,裂隙夹角由T型逐步过渡至Y型;(3)土体颗粒排布总是向稳定方向发育,颗粒间应力分布向着更优势的状态发展,胀缩裂隙分布逐步稳定;(4)将块体离散元应用至膨胀土边坡分析中,实现了考虑裂隙和吸湿膨胀的膨胀土边坡位移场-应力场耦合;(5)干湿循环效应促进了膨胀土裂隙发育,裂隙率增加导致渠坡变形增加和塑性区扩大,在膨胀土渠坡坡脚处变形显著。

STUDY ON MECHANICAL INTERACTIONS BETWEEN SINGLE CARDIAC MYOCYTE AND ELASTIC SUBSTRATE

Quantitative investigation on mechanical characteristics of cardiac myocytes has important physiological significance. Based on elastic substrate technique, this paper develops a set of algorithms for high-efficiency cellular traction recovery. By applying a gradient-based digital image correlation method to track randomly distributed fluorescence microbeads on the deformed substrate induced by single cardiac myocyte, high-resolution substrate displacement field can readily be obtained. By using a numerical algorithm based on the integral Boussinesq solution, cell-substrate tractions are reconstructed in a stable and reliable manner. Finally, spatiotemporal dynamics of a single cardiac myocyte is investigated as it adheres to a polyacrylamide elastic substrate.

Physical Model of Drying Shrinkage of Recycled Aggregate Concrete

We prepared concretes（RC0, RC30, and RC100） with three different mixes. The poresize distribution parameters of RAC were examined by high-precision mercury intrusion method（MIM） and nuclear magnetic resonance（NMR） imaging. A capillary-bundle physical model with random-distribution pores（improved model, IM） was established according to the parameters, and dry-shrinkage strain values were calculated and verified. Results show that in all pore types, capillary pores, and gel pores have the greatest impacts on concrete shrinkage, especially for pores 2.5-50 and 50-100 nm in size. The median radii are 34.2, 31, and 34 nm for RC0, RC30, and RC100, respectively. Moreover, the internal micropore size distribution of RC0 differs from that of RC30 and RC100, and the pore descriptions of MIM and NMR are consistent both in theory and in practice. Compared with the traditional capillary-bundle model, the calculated results of IM have higher accuracy as demonstrated by experimental verifi cation.

On the Geometry of Curves in Minkowski 3-Space and Its Foldings

We will introduce a new connection between some transformations and some aspects of differential geometry of some curves in Minkowski space. The concept of folding, retractions and contraction on some curves in Minkowski space will be characterized by using some aspects of differential geometry. Types of the deformation retracts of some curves in Minkowski 3-space are obtained. The relations between the foldings and the deformation retracts of some curves are deduced. The connections between some transformations and time like, space like, light like of some curves in Minkowski 3-space are also presented.

Advances and expectations of study on wood rheology

By studying and summarizing the characteristics of wood rheology,the mathematic models of creep and mechano-sorptive creep of wood were analyzed.Rheology behaviors in process,especially drying stress and deformation set were discussed.Application of wood rheology in woodcraft process was elaborated and the research prospects and orientation were forecasted.

Characteristics of Deformation Layer for Vermicular Iron under Dry Sliding Friction

At room temperature,dry sliding wear tests were carried out using pin-on-disc test rig,in which the pin is made of vermicular iron and the disc is made of 40 Cr steel.The microstructures of the frictional surfaces for the pin specimens were investigated.Under the action of both frictional heat and frictional shearing stress,aplastic deformation layer under the frictional surface is formed.The morphology and properties of the plastic deformation layer depend on specimen material,contact pressure and frictional shearing stress.In the plastic deformation layer,the phosphorous mass percent varies at different depth and results in different hardness.On the outer side of surface,the hardness is the biggest and the phosphorous mass percent is the highest.They become gradually small from outer side to inner side of the surface.

Cyclic Elasto-Plastic Fracture Diagram and Some Parameters of Cyclic Crack Growth Resistance for the Plastic Steels

Method of calculation and experimental estimation of crack growth resistance under cyclic elastoplastic deformation is proposed. This method is based on measuring of local plastic strain near the crack tip and plotting the cyclic elasto-plastic fracture diagram for a specimen with a crack. Analysis of two types of the cyclic elasto-plastic fracture diagrams and their parameters is made. Ex-perimental D-diagrams of cyclic elasto-plastic fracture for the plastic carbon steel are given.

Formation and evolution of oblique anticline in eastern Niger Delta

Based on the three-dimensional seismic interpretation data,this paper analyzed the formation mechanism and the growth process of the oblique anticline AE of the M region of the eastern Niger Delta,as well as the evolution process of the associated fault systems.The study results show that the stratigraphic sedimentary period between reflector H4-H6 of the middle and late Miocene was the initial fold-thrust stage,the anticline AE was a half-graben controlled by oblique extensional faults derived from the oblique extensional transfer structure formed by local initial differential fold-thrusting.At the same time the tear faults developed as a result of the differential sliding.During the stratigraphic sedimentary period between reflector H1-H4 of the late Miocene to Pliocene,the large-scale folding and thrusting occurred,differential contractional deformation resulted in the pre-existing extensional half-graben became AE anticline by oblique tectonic inversion,then the anticline grew continually and the crest of the anticline migrated gradually.The newly formed fault systems consist of a small number of associated tear-normal faults caused by differential thrusting and gravity-driven domino normal faults predominantly induced by the slope inclination of the anticline limb.During the stratigraphic sedimentary period between reflector H0-H1 of the Pleistocene to Holocene,as the growth of the anticline ceased,the area entered post-fold thrusting stage.The formation and distribution of conjugated faults were controlled by the local gravity return collapse,local differential sliding and reactivation of pre-existing positive inversion faults jointly.The research results of genetic mechanism of the oblique inversion anticline and evolution of associated faults are helpful to reveal the key factors controlling the accumulation and distribution of oil and gas.

Contractibility of Hyperspaces C_k(X)

This paper proves the following results: let X be a continuum, let k, m ∈ N, and let B ∈ C m (X), consider the continuous surjection f k : C k (X) → C k (X). We define the mapping B : C k (X) → C k+m (X): by B (A) = f k (A) B. Then following assertions are equivalent: (1) The hyperspace C k (X) is g-contractible; (2) For each m ∈ N and for each B ∈ C m (X) the mapping B is a W -deformation in C k+m (X); (3) For each m ∈ N there exists B ∈ C m (X) such that the mapping B is a W -deformation in C k+m (X); (4) There exists m ∈ N such that for each B ∈ C m (X) the mapping B is a W -deformation in C k+m (X); (5) There exist m ∈ N and B ∈ C m (X) such that the mapping B is a W -deformation in C k+m (X).

基于Moldex3D对汽车天窗壳数值模拟分析

针对汽车天窗壳在生产过程中易出现包封、缝合线和翘曲变形等问题,首先通过数值模拟软件Moldex3D对天窗壳进行浇注系统、冷却系统设计;其次对零件的充填缺陷、收缩变形和翘曲变形进行模拟分析,得到零件缺陷产生的原因是充填和保压时间不足、零件壁厚不均匀。通过修改零件成形工艺参数充填时间、保压时间和最大射压压力,实现了产品优化。优化方法适用于各类薄壁塑件,一定程度上减少了试错成本,缩短产品的生产周期。

硅灰石替代滑石粉在聚丙烯复合材料中的应用

分别采用滑石粉和硅灰石作为无机填料,在聚丙烯(PP)复合材料中添加不同份数的硅灰石和滑石粉并对其综合性能进行系统研究,采用扫描电子显微镜、万能力学性能试验机、冲击试验机、收缩率测定仪和微卡热变形温度测定仪等对无机粉体的颗粒大小、微观形貌和冲击断面形貌以及复合材料的拉伸和弯曲及冲击性能、收缩率、热变形温度进行了测试。研究结果表明:随着硅灰石粉添加量的逐渐增大,PP复合材料的拉伸强度和收缩率逐渐下降,当滑石粉添加量为20份时,拉伸强度为31.979 MPa,收缩率为1.54%,当硅灰石全部替代滑石粉添加量为20份时,拉伸强度下降到29.022 MPa,收缩率下降到1.32%;复合材料的冲击强度先上升后下降,当硅灰石粉和滑石粉添加量均为10份时,PP复合材料的冲击强度达到最大值,为4.302 kJ/m^(2);PP复合材料的弯曲强度和热变形温度逐渐提升,当滑石粉添加量为20份时,弯曲强度为49.462 MPa,热变形温度为91.2℃,当硅灰石全部替代滑石粉添加量为20份时,弯曲强度上升至58.33 MPa,热变形温度上升至111.7℃。

挛缩鼻畸形的手术治疗进展

随着鼻整形手术的数量增多,多次鼻整形和术后感染易导致挛缩畸形。挛缩鼻畸形主要表现为鼻背软骨长度不足、钝性鼻唇角、鼻尖位置偏高、平视时鼻孔外露、鼻长高比例失调、坚硬挛缩的皮肤软组织罩,鼻背皮肤不规整和黏膜衬里的缺失等,是鼻部整形美容修复中的难点之一。现对挛缩鼻畸形矫正术中常用的矫治方法,以及各种方法的适应证及优缺点进行相关探讨,为临床工作中选取恰当方法提供可参考的依据。

刚挠结合板非导通孔到图形对位能力研究

因软硬结合板有三维组装特性,部分产品根据其特殊的应用场景,要求控制顶层和底层零件的对准度,针对此类要求,客户零件贴装需以非导通孔为基准对位贴合,避免零件偏移,需控制软硬结合板基准点即非导通孔到顶层和底层图形的对位公差为±0.10 mm,软硬结合板受软性材料涨缩变形的影响,按常规的制作工艺,图形到非导通孔的对位能力C_(pK)<1.0,该能力无法实现批量生产;本文主要研究提升高密度互连类软硬结合板中非导通孔到图形的对位公差能力,通过分析孔到图形对位的影响因素,简化图形对位的层次,重新排列非导通孔的加工过程,实现顶层和底层的图形到非导通孔的间距同时满足±0.10 mm的公差要求,提升图形到非导通孔的间距能力C_(pK)>1.67,满足批量生产的要求,同时,为行业内提升软硬结合板非导通孔到图形的对位能力提供参考。

塔里木盆地库车坳陷收缩构造变形模型若干问题的讨论

塔里木盆地库车坳陷中、新生界表现出以逆冲断层、纵弯褶皱为基本结构要素的收缩构造变形特征。本文依据地质-地球物理勘探资料,建立了"薄皮收缩构造"和"分层收缩构造"两种模型,讨论了不同构造变形模型的几何结构、收缩变形量、构造动力学机制等方面的差异,并认为"分层收缩构造模型"更为合理。"分层收缩构造模型"强调塔里木克拉通与南天山之间的侧向挤压,中、新生界受岩层能干性影响而发生分层收缩构造变形,新生界以伴生有破冲断层的滑脱褶皱变形为主,中生界以逆冲断层及相关褶皱变形为主,深层发育基底卷入的逆冲断层和断块构造,但是不同层次的收缩变形量基本保持一致。按照平衡剖面原理测算库车坳陷新生界的收缩量为12～15 km,卷入收缩构造变形的深度在山前应该为20～26 km,因此部分逆冲断层应该切割到盆地基底中。尽管变形强度总体上是自深而浅、自造山带向前陆逐渐减弱,作为浅层强变形的秋里塔格构造带的深层也可能发育一定程度的收缩构造变形,构成深层的油气圈闭。

一个韧性转换挤压带的变形分解作用——以阿尔金断裂带东段为例

变形构造研究显示阿尔金断裂带东段可划分成具有近水平拉伸线理的韧性左行走滑变形域(SS)和具有陡角度倾伏拉伸线理的收缩变形域(PS)。在SS与PS之间的过渡区域还发现中等角度倾伏的拉伸线理。在SS区域内,大量的标志显示剪切作用为左旋走滑,在垂向剖面露头上可看到一些纯剪现象;而在PS变形域,则以垂向上的纯剪应变(垂向拉伸)为主,在水平露头上局部显示出左旋剪切特征。这些现象说明SS变形域以水平方向的简单剪切为主,具有少量垂向上的纯剪应变分量;而PS变形域则以纯剪应变为主,具有少量的水平简单剪切分量。因此,阿尔金东段可看作为一个转换挤压变形带,它可能为塔里木地块与柴达木地块斜向会聚作用的产物。在其韧性变形过程中,被分解成以左行走滑为主的变形域和以水平缩短、垂向拉伸为主的变形域,前者造成平行阿尔金走向的侧向运动,后者则引起阿尔金构造带的缩短、地壳加厚和山体隆升。

不同应力路径下粗粒料力学特性试验研究

采用大型三轴试验机,对粗粒料进行了常规三轴、等p和等应力比等不同应力路径的试验。通过对试验结果进行对比分析,研究了粗粒料在不同应力路径下的应力-应变、变形和强度特性,并对粗粒料的卸载体缩现象进行了分析和探讨。结果表明,应力路径对粗粒料的应力-应变和变形特性影响较大,而对强度特性影响较小;卸载体缩主要是由偏应力比η的变化所引起的,与应力路径关系很大。