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161.
Andrey A. Petrov Sergey A. Fateev Aleksei Yu. Grishko Artem A. Ordinartsev Andrey V. Petrov Alexey Yu. Seregin Pavel V. Dorovatovskii Eugene A. Goodilin Alexey B. Tarasov 《Mendeleev Communications》2021,31(1):14-16
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162.
163.
Artem Plyusnin Jingwei He Cindy Elschner Miho Nakamura Julia Kulkova Axel Spickenheuer Christina Scheffler Lippo V. J. Lassila Niko Moritz 《Molecules (Basel, Switzerland)》2021,26(5)
The use of bioresorbable fracture fixation plates made of aliphatic polyesters have good potential due to good biocompatibility, reduced risk of stress-shielding, and eliminated need for plate removal. However, polyesters are ductile, and their handling properties are limited. We suggested an alternative, PLAMA (PolyLActide functionalized with diMethAcrylate), for the use as the matrix phase for the novel concept of the in situ curable bioresorbable load-bearing composite plate to reduce the limitations of conventional polyesters. The purpose was to obtain a preliminary understanding of the chemical and physical properties and the biological safety of PLAMA from the prospective of the novel concept. Modifications with different molecular masses (PLAMA-500 and PLAMA-1000) were synthesized. The efficiency of curing was assessed by the degree of convergence (DC). The mechanical properties were obtained by tensile test and thermomechanical analysis. The bioresorbability was investigated by immersion in simulated body fluid. The biocompatibility was studied in cell morphology and viability tests. PLAMA-500 showed better DC and mechanical properties, and slower bioresorbability than PLAMA-1000. Both did not prevent proliferation and normal morphological development of cells. We concluded that PLAMA-500 has potential for the use as the matrix material for bioresorbable load-bearing composite fracture fixation plates. 相似文献
164.
165.
Bogatyrenko T. N. Kandalintseva N. V. Sashenkova T. E. Allayarova U. Yu. Mishchenko D. V. 《Russian Chemical Bulletin》2022,71(3):517-523
Russian Chemical Bulletin - The interaction of a combination of a sulfur-containing phenolic antioxidant sodium 3-(3-tert-butyl-4-hydroxyphenyl)propylthiosulfate (TS-13) with a nitric oxide donor... 相似文献
166.
167.
The Evens-Lu-Weinstein representation (Q
A
, D) for a Lie algebroid A on a manifold M is studied in the transitive case. To consider at the same time non-oriented manifolds as well, this representation is slightly
modified to (Q
A
or
, Dor) by tensoring by orientation flat line bundle, Q
A
or
=QA⊗or (M) and D
or=D⊗∂
A
or
. It is shown that the induced cohomology pairing is nondegenerate and that the representation (Q
A
or
, Dor) is the unique (up to isomorphy) line representation for which the top group of compactly supported cohomology is nontrivial.
In the case of trivial Lie algebroid A=TM the theorem reduce to the following: the orientation flat bundle (or (M), ∂
A
or
) is the unique (up to isomorphy) flat line bundle (ξ, ∇) for which the twisted de Rham complex of compactly supported differential
forms on M with values in ξ possesses the nontrivial cohomology group in the top dimension. Finally it is obtained the characterization
of transitive Lie algebroids for which the Lie algebroid cohomology with trivial coefficients (or with coefficients in the
orientation flat line bundle) gives Poincaré duality. In proofs of these theorems for Lie algebroids it is used the Hochschild-Serre
spectral sequence and it is shown the general fact concerning pairings between graded filtered differential ℝ-vector spaces:
assuming that the second terms live in the finite rectangular, nondegeneration of the pairing for the second terms (which
can be infinite dimensional) implies the same for cohomology spaces. 相似文献
168.
169.
170.
We consider the ground state energy of a massive scalar field in the space-time of a thick cosmic string in the 2+1 dimensional case for arbitrary angle deficit by using the zeta-function approach. Final numerical calculations were made in the massless case, only. We show that the zero point energy is negative, and for small angle deficit it is proportional to the fourth degree of the deficit. 相似文献