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排序方式: 共有231条查询结果,搜索用时 140 毫秒
1.
Huifang Chen Yannan Song Yafang Peng Meifeng Wang Wubliker Dessie Gregory J. Duns Lijian Xu Xiaofang Luo Zuodong Qin 《Macromolecular bioscience》2023,23(4):2200514
Bacterial infections of the wound surface can be painful for patients, and traditional dressings do not effectively address this problem. In this study, an antimicrobial wound dressing is prepared using a novel antimicrobial peptide, HX-12C. This hydrogel system is based on the natural biomaterials sodium alginate and gelatin, utilizing calcium carbonate as a source of Ca2+, and ionic cross-linking is facilitated by lowering the solution pH. The resulting sodium alginate/gelatin HX-12C-loaded hydrogel (CaAGEAM) has good mechanical and adhesion properties, biocompatibility and in vitro degradability. Its extraordinary antibacterial efficacy (>98%) is verified by an antibacterial experiment. More importantly, in vivo experiments further demonstrate its healing-promotion effect, with a 95% wound healing rate by day 9. Tissue staining demonstrates that the hydrogel containing antimicrobial peptides is effective in suppressing inflammation. The dressing promotes wound healing by stimulating the deposition of skin appendages and collagen. The results of this study suggest that composite hydrogels containing antimicrobial peptides are a promising new type of dressing to promote the healing of infected wounds. 相似文献
2.
Luke Gordon Joel B. Varley John L. Lyons Anderson Janotti Chris G. Van de Walle 《固体物理学:研究快报》2015,9(8):462-465
Achieving high levels of n‐type conductivity in AlN and high Al‐content nitride alloys is a long standing problem; significant decreases in conductivity are observed as the Al content is increased, a phenomenon that has been attributed to donors such as oxygen or silicon forming DX centers. We address this problem through a comprehensive first‐principles hybrid density functional study of potential n‐type dopants, identifying SN and SeN as two elements which are potential shallow donors because they do not undergo a DX transition. In particular, SN is highly promising as an n‐type dopant because it also has a low formation energy and hence a high solubility. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
3.
Gregory S. Pomrehn Alex Zevalkink Wolfgang G. Zeier Axel van de Walle G. Jeffrey Snyder 《Angewandte Chemie (International ed. in English)》2014,53(13):3422-3426
Experimentally, AZn2Sb2 samples (A=Ca, Sr, Eu, Yb) are found to have large charge carrier concentrations that increase with increasing electronegativity of A. Using density functional theory (DFT) calculations, we show that this trend can be explained by stable cation vacancies and the corresponding finite phase width in A1?xZn2Sb2 compounds. 相似文献
4.
Klavdija Kutnar Urban Borštnik Dragan Marušič Dušanka Janežič 《Journal of mathematical chemistry》2009,45(2):372-385
A class of interconnection networks for efficient parallel MD simulations based on hamiltonian cubic symmetric graphs is presented.
The cubic symmetric graphs have many desirable properties as interconnection networks since they have a low degree and are
vertex- and edge-transitive. We present a method for scheduling collective communication routines that are used in parallel
MD and are based on the property that the graphs in question have a Hamilton cycle, that is, a cycle going through all vertices
of the graph. Analyzing these communication routines shows that hamiltonian cubic symmetric graphs of small diameter are good
candidates for a topology that gives rise to an interconnection network with excellent properties, allowing faster communication
and thus speeding up parallel MD simulation. 相似文献
5.
The transport of a reactive solute by diffusion and convection in a thin (or long) curved pipe is considered. Using asymptotic analysis with respect to the pipe’s thickness, the effective model for solute concentration is formally derived. A simple approximation is computed, showing explicitly the effects of the pipe’s geometry in nature and magnitude. 相似文献
6.
7.
Enantiomers represent a class of compounds extensively investigated since they can show totally different behaviors when they interact with a chiral environment. Because of their identical chemical structure (they differ only in the spatial arrangement of the atoms in the molecule), the separation of optical isomers is a challenging task of analytical chemistry. So far employed methods for the separation of enantiomers are mainly based on chromatography. CE as well was considered as an analytical technique suitable for chiral separations, characterized by high efficiency and low consumption of reagent. Recently, miniaturization was introduced in LC to answer the needs to perform analyses in the minimum time, to use the smallest amount of samples and to reduce environmental pollution. Nano‐LC represents nowadays a valid alternative to the abovementioned conventional analytical techniques, and can be advantageously exploited for enantiomeric separation especially because it needs minute amounts of the chiral material necessary to carry out enantiomeric separations. This review describes the development and applications of nano‐LC in the field of chiral separations. The data reported in literature show its relevance for the study enantiomers‐chiral selectors interaction, as well as for application in pharmaceutical and clinical research. 相似文献
8.
9.
H. Postma B. Kastelein N. Severijns D. Vandeplassche J. Vanhaverbeke L. Vanneste E. van Walle J. Wouters J. van Klinken 《Hyperfine Interactions》1989,52(1):79-88
Gamma-ray anisotropy measurements have been carried out with brute-force oriented178m
2Hf (16+) to derive its magnetic moment 7.26 (±0.16; +0.2/−0) nm and E2/M1 mixing ratios of some γ-transitions observed in the decay
of this isomer. This magnetic moment is in agreement with an earlier proposed four-quasi-particle configuration. The magnetic
moment of the 8− isomer at 1147.7 keV (4.0 s) is estimated to be between 1.4 and 5.3 nm, which confirms mixing of the {p[514]9/2 +p[404]7/2}8− and {n[514]7/2+n[624]9/2}8− configurations, which summed together give the 16+ isomer. 相似文献
10.
Following Alspach and Parsons, a metacirculant graph is a graph admitting a transitive group generated by two automorphisms ρ and σ, where ρ is (m,n)-semiregular for some integers m≥1, n≥2, and where σ normalizes ρ, cyclically permuting the orbits of ρ in such a way that σ
m
has at least one fixed vertex. A half-arc-transitive graph is a vertex- and edge- but not arc-transitive graph. In this article quartic half-arc-transitive metacirculants are explored
and their connection to the so called tightly attached quartic half-arc-transitive graphs is explored. It is shown that there
are three essentially different possibilities for a quartic half-arc-transitive metacirculant which is not tightly attached
to exist. These graphs are extensively studied and some infinite families of such graphs are constructed.
Both authors were supported in part by “ARRS – Agencija za znanost Republike Slovenije”, program no. P1-0285. 相似文献