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1.
The rotator cuff repaired construct must establish a contiguous and functioning tendon-bone junction to provide adequate stability. However, fibrocartilage deficiency and bone loss were hardly reversed after physical suture, especially in chronic rotator cuff tears. In this study, we synthesized an injectable methylcellulose/polyvinyl alcohol/polyvinylpyrrolidone-based thermo-sensitive hydrogel, which delivered kartogenin-loaded mesoporous bioactive glass nanoparticles. Physicochemical studies the revealed phase transition temperatures of 35 °C and its ability to induce chondrogenesis and osteogenesis differentiation of tendon-derived stem cells. Furthermore, experiments in rabbit chronic rotator cuff tears model confirmed the fibrocartilage and bone layer regenerative capability of the injected bioactive hydrogel, which could, in turn, support the ultimate tensile stress of the repaired rotator cuff. The bioactive agents-loaded hydrogel reported in this study is a valuable addition to the arsenal of biomaterials in applications to chronic tendon-bone junction injuries.  相似文献   
2.
Czechoslovak Mathematical Journal - We give a complete characterization of closed sets F ? ?2 whose distance function dF:= dist(·, F) is DC (i.e., is the difference of two convex...  相似文献   
3.
Czechoslovak Mathematical Journal - A nonincreasing sequence π = (d1,…, dn) of nonnegative integers is a graphic sequence if it is realizable by a simple graph G on n vertices. In this...  相似文献   
4.
We investigate a diffusive, stage-structured epidemic model with the maturation delay and freelymoving delay. Choosing delays and diffusive rates as bifurcation parameters, the only possible way to destabilize the endemic equilibrium is through Hopf bifurcation. The normal forms of Hopf bifurcations on the center manifold are calculated, and explicit formulae determining the criticality of bifurcations are derived. There are two different kinds of stable oscillations near the first bifurcation: ...  相似文献   
5.
Zhao  Feng  Ji  Jinchen  Luo  Quantian  Cao  Shuqian  Chen  Lumin  Du  Wenliao 《Nonlinear dynamics》2021,104(1):349-365
Nonlinear Dynamics - Quasi-zero stiffness (QZS) isolators can achieve superior performance in vibration isolation; however, this superiority is often effective only for an excitation with the small...  相似文献   
6.
Fuzzy Optimization and Decision Making - Quality function deployment (QFD) is a customer-oriented product/service design tool with diversified team members reaching a consensus in developing a new...  相似文献   
7.
The author proposes a two-dimensional generalization of Constantin-Lax-Majda model. Some results about singular solutions are given. This model might be the first step toward the singular solutions of the Euler equations. Along the same line (vorticity formulation), the author presents some further model equations. He possibly models various aspects of difficulties related with the singular solutions of the Euler and Navier-Stokes equations. Some discussions on the possible connection between turbulence and the singular solutions of the Navier-Stokes equations are made.  相似文献   
8.
2020年高考物理试题依托高考评价体系,结合物理学科特点,考试内容以学科素养考查为导向,即以物理观念、科学思维、科学探究、科学态度与责任的物理学科素养为导向,注重对核心物理概念和规律的考查,引导学生夯实学习发展的基础,促进中学重视培养学生的基础知识、基本技能以及提升学生的基本素养.基于物理学科素养,论证分析2020年高考全国理综卷Ⅰ物理压轴计算题,助力培养学生科学思维.  相似文献   
9.
Li  Qingtao  Du  Guangzhi 《Numerical Algorithms》2021,88(4):1915-1936
Numerical Algorithms - In this paper, some local and parallel finite element methods based on two-grid discretizations are proposed and investigated for the unsteady Navier-Stokes equations. The...  相似文献   
10.
郑琦  黄立  包德亮  武荣庭  李彦  林晓  杜世萱  高鸿钧 《中国物理 B》2022,31(1):18202-018202
The linkage structures between monomers make great influence on the properties of polymers.The synthesis of some special linkage structures can be challenging,which is often overcome by employing special reaction conditions.Here,we build dihydropentalene linkage in poly-naphthalocyanine on Ag(110)surface.Scanning tunneling microscopy(STM)and non-contact atomic force microscopy(nc-AFM)measurements confirm the dihydropentalene linkage structure and a possible formation path with reconstruction steps is proposed.The controlled experiment on Ag(100)surface shows no dihydropentalene structures formed,which indicates the grooved substrate is necessary for the reconstruction.This work provides insights into the surface restricted reactions that can yield special structures in organic polymers.  相似文献   
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