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51.
Abstract

Fullerene C60 is known as a promising therapeutic agent due to its antioxidant, anti-inflammatory and other properties, along with the lack of noticeable toxicity. In this article, we describe antiviral properties of aqueous fullerene C60 dispersion (ndC60) produced by biocompatible diafiltration technology and C60 amino derivatives against Herpes simplex virus type 1 (HSV-1) and Human cytomegalovirus (HCMV) infections. Their activity in vitro was evaluated by a plaque reduction assay using Vero and HF cells in pre- and post-treatment modes. Therapeutic efficacy of dnC60 and C60 derivatives was studied in DBA mice using cutaneous model of HSV-1 infection. Data obtained indicated low cytotoxicity of all used compounds for both cell lines (CC50 > 1?mg/ml). The antiviral activity of dnC60 in most tests exceeded the activity of both C60 amino adducts and acyclovir (ACV), and it demonstrated significant therapeutic effect against HSV-1 skin infection in mice.  相似文献   
52.
To assess endocrinologic and metabolic research productivity in East Asia (i.e., China, Japan, and South Korea) and correlations between socioeconomic factors and endocrinologic and metabolic research productivity. Articles (except editorials, conference abstracts, letters, news, and corrections) published in 134 endocrinology and metabolism journals in 2005–2014 were screened with the Web of Science database. Total and annual numbers of articles, study designs, impact factors, citations, and articles in high-impact-factor journals were determined for China, Japan, and South Korea. Annual numbers of articles were related to socioeconomic factors for each country. In 2005–2014, there were 144,660 articles from East Asia published in endocrinology and metabolism journals: 10,190, 9470, and 3124 from Japan, China, and South Korea, respectively. Japan published the most randomized controlled trials, followed by China and South Korea, respectively. China had the most articles in high-impact-factor journals, followed by Japan and South Korea, respectively. South Korea had the highest average impact factor and number of citations. During the period studied, annual numbers of articles from China and South Korea increased remarkably (P < 0.05) but remained stable for Japan. Annual numbers of articles from China and South Korea were positively correlated with gross domestic product and expenditure on health care (P < 0.05). The increase in endocrinology and metabolism articles during 2005–2014 in China and South Korea was associated with improved socioeconomic conditions. China has made progress in scientific publication in the past decade; however, there is still room for improvement.  相似文献   
53.
54.
Journal of Materials Science - One of the big challenges for realizing future nuclear fusion reactors is the development of materials able to withstand the high thermal loads and particle fluxes...  相似文献   
55.
This paper describes a four-variable model for an enzymatic oscillator based on trypsin. Variables in this model are concentrations of the essential proteins (trypsin and trypsinogen) and small molecules (masked and active inhibitors of trypsin) within the network. Importantly, to simplify the model, non-essential side reactions are neglected and essential reactions are assumed to follow first or second order kinetics. Numerical solutions of this reduced model semi-quantitatively reproduce experimentally determined periods, amplitudes, and phase shifts of oscillations in the concentrations of several species in the network. Moreover, linear stability analysis shows that oscillations in the trypsin oscillator emerge and disappear through Hopf bifurcation. The model will be helpful in situations where simplicity is necessary such as detailed analysis of dynamics and modeling of reaction-diffusion systems.  相似文献   
56.
Interdiffusion processes between aluminum enriched PVD‐sputtered silica thin films and industrial float soda‐lime silicate glass substrates are quantitatively studied using SIMS analysis. Heat treatments are performed at temperatures close or above the glass transition temperature of the float glass. Aluminum doping of the film is shown to strongly increase the migration of alkali from the glass substrate to the silica thin film. In particular the final alkali content in the film exhibits a linear scaling with the aluminum concentration. An interdiffusion process is evidenced between bulk alkali ions and protons originating from a significant water content in the as‐deposited silica film. Experimental measurements of sodium concentration are shown to be consistent with a simple thermodynamic model based on the equilibration of the activity of sodium between the film and the glass substrate.  相似文献   
57.
We studied the effect of the substrate on the surface-enhanced Raman scattering (SERS) signals of metallic nanocrystal films by making a direct comparison between cases with metallic and semiconducting substrate surfaces. Ag nanoparticles smaller than 10?nm were synthesized and uniform arrays were formed on both ultrasmooth metallic and Si surfaces. These substrates provide reproducible SERS signals with high enhancement factors over large areas. Moreover, a SERS signal about one order of magnitude higher was obtained in the metallic surface case as compared with the Si substrate case, which is attributed to stronger plasmon coupling between the nanoparticles and their charge-conjugate images in the underlying metallic surface. The interpretation of our experimental results was confirmed by our finite difference time domain calculations. The dependence of the interaction between the nanoparticles and the substrate surface on the direction of the incident electromagnetic field is also discussed.  相似文献   
58.
In a recent paper we examined a model of an arch bridge with viscous damping subjected to a sinusoidally varying central load. We showed how this yields a useful archetypal oscillator which can be used to study the transition from smooth to discontinuous dynamics as a parameter, alpha, tends to zero. Decreasing this smoothness parameter (a non-dimensional measure of the span of the arch) changes the smooth load-deflection curve associated with snap-buckling into a discontinuous sawtooth. The smooth snap-buckling curve is not amenable to closed-form theoretical analysis, so we here introduce a piecewise linearization that correctly fits the sawtooth in the limit at alpha=0. Using a Hamiltonian formulation of this linearization, we derive an analytical expression for the unperturbed homoclinic orbit, and make a Melnikov analysis to detect the homoclinic tangling under the perturbation of damping and driving. Finally, a semi-analytical method is used to examine the full nonlinear dynamics of the perturbed piecewise linear system. A chaotic attractor located at alpha=0.2 compares extremely well with that exhibited by the original arch model: the topological structures are the same, and Lyapunov exponents (and dimensions) are in good agreement.  相似文献   
59.
H-Oil vacuum gas oils obtained during hydrocracking of vacuum residual oils originated from the crudes Russian Export Blend, Basrah light, and Heavy Kazakh were cracked in a mixture with a hydrotreated vacuum gas oil in the LUKOIL Neftohim Burgas commercial fluid catalytic cracking (FCC) unit. Some of the H-Oil vacuum gas oils were also cracked in a laboratory FCC (ACE) unit. The results from the commercial and the laboratory tests showed that the laboratory FCC experiments in an ACE unit can be used to evaluate the effect of feed quality on the commercial FCC unit performance. The assumption that the conversion of a vacuum gas oil (VGO) blend in the fluid catalytic cracking could be considered as a linear combination of the conversion of the individual components made by other researchers was also confirmed in this study. The higher the hydrogen content in the vacuum residual oil of a crude is the higher the FCC conversion of the H-Oil VGO, obtained during hydrocracking of that high saturate vacuum residual oil, will be expected.  相似文献   
60.
Pompe disease (OMIM#232300) is an autosomal recessive lysosomal storage disorder caused by mutations in the GAA gene. According to public mutation databases, more than 679 pathogenic variants have been described in GAA, none of which are associated with mobile genetic elements. In this article, we report a novel molecular genetic cause of Pompe disease, which could be hardly detected using routine molecular genetic analysis. Whole genome sequencing followed by comprehensive functional analysis allowed us to discover and characterize a complex mobile genetic element insertion deep in the intron 15 of the GAA gene in a patient with infantile onset Pompe disease.  相似文献   
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