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51.
X-ray imaging functionalization of biodegradable polyesters is a great demand and challenge in biomedical applications.In this work,a strategy of in-chain functionalization through the combination of ring opening copolymerization and oxime "Click" postfunctionalization was developed towards X-ray opaque polylactide copolymers.A functionalized cyclic carbonate was first synthesized and used as comonomer of polylactide copolymers,which were subjected to postfunctionalization of oxime "Click" reaction towards iodinated polylactide copolymers.The chemical structure and physical properties of the target products were traced and confirmed.In vitro cytotoxicity evaluation with 3T3-Swiss albino by Alamar blue demonstrated a low cytotoxicity.The X-ray radiopacity was analyzed by Micro-CT and quantified by Hounsfield Units value,which could be tailorable by the feedstock.It is a promising X-ray visible implantable biomaterial in biomedical applications. 相似文献
52.
Syed Mohammed Basheeruddin Asdaq Earla Swathi Sunil S Dhamanigi Mohammed Asad Yahya Ali Mohzari Ahmed A. Alrashed Abdulrahman S. Alotaibi Batool Mohammed Alhassan Sreeharsha Nagaraja 《Molecules (Basel, Switzerland)》2020,25(22)
The carrot plant (Daucus carota) and its components are traditionally reported for the management of gastric ulcers. This study was performed to evaluate the role of carrot when administered concurrently with a conventional antiulcer treatment, pantoprazole, in alleviating gastric and duodenal ulcers in female experimental animals. The study involved standard animal models to determine the ulcer preventive effect using pylorus ligation, ethanol, and stress induced acute gastric ulcer models and duodenal ulcer models involving cysteamine. Acetic acid-induced chronic gastric ulcer and indomethacin-induced gastric ulcer models were used to evaluate the ulcer healing effect. Carrot fruit (500 mg/kg) and its co-administration with pantoprazole produced significant protection in an ethanol- and stress-induced acute gastric ulcer and cysteamine-induced duodenal ulcer. The healing of the acetic acid-induced chronic gastric ulcer was also augmented with this combination. Both total proteins and mucin contents were significantly increased in indomethacin-induced gastric ulcers. Similarly, in pylorus ligation, the pepsin content of gastric juice, total acidity, and free acidity were reduced. Overall, both ulcer preventive effects and ulcer healing properties of the pantoprazole were significantly enhanced in animals who received the co-administration of carrot fruit (500 mg/kg). 相似文献
53.
Tomas Do Roman Guran Rea Jarosova Petra Ondrackova Zbysek Sladek Martin Faldyna Vojtech Adam Ondrej Zitka 《Molecules (Basel, Switzerland)》2020,25(23)
Respiratory infections are a real threat for humans, and therefore the pig model is of interest for studies. As one of a case for studies, Actinobacillus pleuropneumoniae (APP) caused infections and still worries many pig breeders around the world. To better understand the influence of pathogenic effect of APP on a respiratory system—lungs and tracheobronchial lymph nodes (TBLN), we aimed to employ matrix-assisted laser desorption/ionization time-of-flight mass spectrometry imaging (MALDI-TOF MSI). In this study, six pigs were intranasally infected by APP and two were used as non-infected control, and 48 cryosections have been obtained. MALDI-TOF MSI and immunohistochemistry (IHC) were used to study spatial distribution of infectious markers, especially interleukins, in cryosections of porcine tissues of lungs (necrotic area, marginal zone) and tracheobronchial lymph nodes (TBLN) from pigs infected by APP. CD163, interleukin 1β (IL-1β) and a protegrin-4 precursor were successfully detected based on their tryptic fragments. CD163 and IL-1β were confirmed also by IHC. The protegrin-4 precursor was identified by MALDI-TOF/TOF directly on the tissue cryosections. CD163, IL-1β and protegrin-4 precursor were all significantly (p < 0.001) more expressed in necrotic areas of lungs infected by APP than in marginal zone, TBLN and in control lungs. 相似文献
54.
Three mesoporous molecular sieves loaded silicotungstic acids, named HSiW/SBA-15, HSiW/MCM-41, HSiW/MCM-48, were prepared and characterised by XRD, FT-IR, TEM and SEM. The catalytic performance of the prepared materials for the Baeyer-Villiger oxidation of cyclic ketones was carried out in the presence of 30%H2O2 under mild conditions. These loading materials were proved to be efficient and reusable catalysts, they all exhibited excellent catalytic performance for the Baeyer-Villiger oxidation of cyclic ketones with 30% H2O2 as oxidant. Many cyclic ketones were efficiently converted to the corresponding lactones with up to 90% conversions and high selectivities under the optimum reaction conditions. Cyclic ketones were efficiently oxidised by mesoporous materials sopported silicotungstic acid to the corresponding lactones with 30%H2O2 as oxidant. All of the catalysts showed promising recyclability in the reactions. 相似文献
55.
Florio M. Ciaglia Fabio Di Cosmo Alberto Ibort Giuseppe Marmo 《Entropy (Basel, Switzerland)》2020,22(11)
The evolution of states of the composition of classical and quantum systems in the groupoid formalism for physical theories introduced recently is discussed. It is shown that the notion of a classical system, in the sense of Birkhoff and von Neumann, is equivalent, in the case of systems with a countable number of outputs, to a totally disconnected groupoid with Abelian von Neumann algebra. The impossibility of evolving a separable state of a composite system made up of a classical and a quantum one into an entangled state by means of a unitary evolution is proven in accordance with Raggio’s theorem, which is extended to include a new family of separable states corresponding to the composition of a system with a totally disconnected space of outcomes and a quantum one. 相似文献
56.
57.
Phase-resolved information is necessary for many coastal wave problems, for example, for the wave conditions in the vicinity of harbor structures. Two-dimensional (2D) depth-averaging shallow water models are commonly used to obtain a phase-resolved solution near the coast. These models are in general more computationally effective compared with computational fluid dynamics software and will be even more capable if equipped with a parallelized code. In the current article, a 2D wave model solving the depth-averaged continuity equation and the Euler equations is implemented in the open-source hydrodynamic code REEF3D. The model is based on a nonhydrostatic extension and a quadratic vertical pressure profile assumption, which provides a better approximation of the frequency dispersion. It is the first model of its kind to employ high-order discretization schemes and to be fully parallelized following the domain decomposition strategy. Wave generation and absorption are achieved with a relaxation method. The simulations of nonlinear long wave propagations and transformations over nonconstant bathymetries are presented. The results are compared with benchmark wave propagation cases. A large-scale wave propagation simulation over realistic irregular topography is shown to demonstrate the model's capability of solving operational large-scale problems. 相似文献
58.
59.
固体氧化物燃料电池的翘曲会影响电极-盖板界面的接触情况,从而影响电化学性能,对相关制造工艺提出了很大的挑战.为了分析燃料电池平面度对放电过程的影响,揭示其潜在的风险,我们建立了两个基于有限元法的仿真模型,对考虑平面度缺陷的燃料电池封装和放电进行分析.在对固体氧化物燃料电池进行平面度测量的基础上,首先建立了具有真实燃料电池翘曲特性的几何模型,分析封装过程中接触压力的分布情况.然后将接触电阻的仿真结果导入到三维多物理场耦合模型中,模拟具有平面度缺陷的燃料电池电化学性能.计算结果展示了燃料电池两侧封装过程中接触压力的分布情况.通过对比有接触电阻和无接触电阻的燃料电池电流密度,分析了电池与盖板的接触对放电过程的影响.结果表明,燃料电池的凹陷面较难达到满意的接触状态,需要比凸起面更大的封装压力.燃料电池表面接触电阻的变化将引起电流传导路径的变化,产生局部高电流或低电流.这项工作强调了在燃料电池中保持均匀分布的接触电阻的重要性,为今后的优化工作奠定了基础. 相似文献
60.
Dr. Silvia Castro-Fernández Carlos M. Cruz Dr. Inês F. A. Mariz Dr. Irene R. Márquez Vicente G. Jiménez Lucía Palomino-Ruiz Prof. Juan M. Cuerva Dr. Ermelinda Maçôas Dr. Araceli G. Campaña 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(18):7205-7211
A new family of distorted ribbon-shaped nanographenes was designed, synthesized, and their optical and electrochemical properties were evaluated, pointing out an unprecedented correlation between their structural characteristics and the two-photon absorption (TPA) responses and electrochemical band gaps. Three nanographene ribbons have been prepared: a seven-membered-ring-containing nanographene presenting a tropone moiety at the edge, its full-carbon analogue, and a purely hexagonal one. We have found that the TPA cross-sections and the electrochemical band gaps of the seven-membered-ring-containing compounds are higher and lower, respectively, than those of the fully hexagonal polycyclic aromatic hydrocarbon (PAH). Interestingly, the inclusion of additional curvature has a positive effect in terms of non-linear optical properties of those ribbons. 相似文献