调整节点矢量对B样条曲线的影响

本文研究了调整一个节点对B样条曲线产生的影响。调整B样条曲线的一个节点,引起两个节点区间改变。讨论了这两个节点区间上有定义的B样条基函数所发生的变化,以及对B样条曲线产生的影响。研究表明,通过调整一个节点可以方便地调整B样条曲线的形状,为B样条曲线形状调整提供了一种简便有效的方法,这在很大程度上丰富了B样条曲
线形状调整的方法。     

Cyclotide Structures Revealed by NMR,with a Little Help from X-ray Crystallography

This review highlights the predominant role that NMR has had in determining the structures of cyclotides, a fascinating class of macrocyclic peptides found in plants. Cyclotides contain a cystine knot, a compact structural motif that is constrained by three disulfide bonds and able to resist chemical and biological degradation. Their resistance to proteolytic degradation has made cyclotides appealing as drug leads. Herein, we examine the developments that led to the identification and conclusive determination of the disulfide connectivity of cyclotides and describe in detail the structural features of exemplar cyclotides. We also review the role that X-ray crystallography has played in resolving cyclotide structures and describe how racemic crystallography opened up the possibility of obtaining previously inaccessible X-ray structures of cyclotides.     

Tensile,Knot, and Detaching from Needle Performances of Atraumatic Surgical Sutures

In this study, atraumatic surgical sutures were used to investigate the effects of different structural parameters on tensile properties of unknotted and knotted (one, two, and three) sutures. Besides tensile properties, an important and crucial property namely detaching from needle property of the sutures were examined. Atraumatic surgical sutures having different lifetime in the body (nonabsorbable and absorbable), different raw materials (polypropylene [PP], silk, polydioxanone [PDS], polyglactin 910 [PGA]), different yarn structures (monofilament and braided), and different size numbers (2/0, 3/0, and 4/0 USP) were tested and variance analyses were used to examine the effects of structural parameters on test results. Tensile test results revealed that the presence of knot causes noticeable reduction in the breaking load values. However, the knotted sutures with varying throw number of knots were determined to have similar breaking properties. In addition, breaking load and detaching force from needle decrease with increasing size number of the sutures. In the case of the same size number and the same throw number of knot, absorbable sutures have higher breaking load results than non-absorbable sutures and braided sutures are stronger than monofilament sutures used in the study.     

拓扑与褶皱——当代前卫建筑的非欧几何实验

论述了拓扑几何的概念及主要命题,包括皱褶、纽结与流形。比较了拓扑几何下的建筑审美体系与欧式几何体系下是如何的不同。分析了拓扑几何对当代先锋主义建筑实验、高维建筑空间、甚至拓扑城市的巨大影响。最后,归纳了拓扑学思想下的建筑美学新范式——褶皱美学。     

Holomorphic Dynamics in Loop Spaces

We discuss a certain type of evolution of loops in smooth manifolds described in terms of natural almost complex structures on appropriate loop spaces. The main attention is paid to holomorphic families of transverse loops in a Cauchy–Riemann manifold, with an emphasis on the geometry of their images. In this context, we introduce a special class of foliated solid tori, called holomorphic doughnuts, and show that they are connected with certain classical geometric constructions. In particular, we show that holomorphic doughnuts can be obtained from isolated singularities of algebraic plane curves. We also establish the existence of holomorphic dynamics for generic real-analytic loops. 2000 Mathematics Subject Classification. 32Q60, 35Q15, 58D15.     

单板节子快速检测研究现状

介绍了单板节子快速检测的研究现状,为进一步开发新的单板节子快速检测方法提供了参考.     

关于低质、低效木胶合板模板评价问题的研讨

关于木胶合板模板的应用,有专家主张现行木胶合板模板性能好,使用方便,能满足清水混凝土施工要求,且价格最低,是施工企业应用最多的模板,也是理想的模板材料,而本文则通过对木胶合板模板在应用过程中表现出低质、低效问题的分析,提出了治理、限制木胶合板模板应用及多元代木的观点和主张。     

绳索救援中普鲁士抓结受力测试研究

通过室内外试验，实际测定了不同状态下，常用双股、三股普鲁士抓结作用在10.5、12.5 mm 主绳下的受力情况、形变程度、失效强度，根据普鲁士抓结的结构特点和各种情况下的受力测试结果，探讨了其结构的安全性、稳定性。通过介绍和研究，对消防队伍灭火救援工作中普鲁士抓结应用的安全性提供参考，并对其他绳结的试验研究有所启发。     

Enhancing water repellence and mechanical properties of antibacterial gelatin/Ce(Ⅲ) fiber by heat treatment

The water repellence and mechanical properties of the gelatin/Ce(Ⅲ) fiber(GCe fiber) were improved by heat treatment,which was an easy and non-toxic method.The microscopic morphology,mechanical properties,antibacterial activity,and cell culture of the GCe fibers by heat treatment(HGCe fiber) were investigated.It was found that the water repellence and mechanical properties of the HGCe fibers increased significantly along with temperature increase.SEM observation showed that HGCe fibers had a fairly smooth surface and a compact structure.Detailed characterization revealed that the HGCe fibers exhibited similar antibacterial activity with the GCe fibers against Staphylococcus aureus.In addition,the results of cell culture by morphological assessment and methylthiazolyl tetrazolium assay(MTT assay) indicated the good biocompatibility of GCe fibers.Therefore,the HGCe fibers could be a promising candidate biomaterial for biomedicine applications.