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Myocardial infarction is one of the leading causes of death worldwide, despite numerous efforts to find efficient prognostic biomarkers and treatment targets. In the present study, we aimed to assess the potential of six microRNAs known to be involved in cardiovascular diseases, cell-free DNA (cfDNA), and mitochondrial DNA (mtDNA) circulating in plasma to be used as prognostic tools for the occurrence of unfavorable outcomes such as major adverse cardiovascular events (MACE) after acute ST-segment elevation myocardial infarction (STEMI). Fifty STEMI patients were enrolled and monitored for 6 months for the occurrence of MACE. Plasma was collected at three time points: upon admission to hospital (T0), at discharge from hospital (T1), and 6 months post-STEMI (T6). Plasma levels of miR-223-3p, miR-142-3p, miR-155-5p, miR-486-5p, miR-125a-5p, and miR-146a-5p, as well as of cfDNA and mtDNA, were measured by RT-qPCR. Results showed that the levels of all measured miRNAs, as well as of cfDNA and mtDNA, were the most increased at T1, compared to the other two time points. In the plasma of STEMI patients with MACE compared to those without MACE, we determined increased levels of miRNAs, cfDNA, and mtDNA at T1. Hence, we used the levels of all measured parameters at T1 for further statistical analysis. Statistical analysis demonstrated that all six miRNAs and cfDNA plus mtDNA levels, respectively, were associated with MACE. The minimal statistical model that could predict MACE in STEMI patients was the combination of mtDNA and miR-142-3p levels, as evidenced by ROC analysis (AUC = 0.97, p < 0.001). In conclusion, the increased plasma levels of mtDNA, along with miR-142-3p, could be used to predict unfavorable outcomes in STEMI patients.  相似文献   
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The effects of Neodymium (Nd) on the electrical properties of low density polyethylene in relation with morphological aspects are reported in this article. Scanning electron microscopy and optical microscopy revealed a quasi-uniform dispersion of Nd particles in polyethylene, both individual particles and clusters being observed. Contact angle measurements showed a decrease of contact angle values and, thus, of surface hydrophobicity, with the increase of Nd content. The addition of Nd in polyethylene determined the increase of electric permittivity and conductivity. The variation of permittivity was explained considering the influence of polar species (additives, oxidation products, neodymium oxide), highlighted by Fourier transform infrared analysis.  相似文献   
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D. D. Stancu 《Calcolo》1983,20(2):211-229
In this paper we first use a probabilistic method to construct a linear positive polynomial operatorL m, r α,β Bernstein type, depending on a non-negative integer parameterr and on two real parameters α and β, such that 0≤α≤β. Then we investigate the approximation properties of this operator mapping into itself the Banach spaceC[0,1] of real-valued continuous functions on [0,1]. A special attention is accorded to the case of the operatorL m,r=L m,r 0,0 . We prove that the remainder of the approximation formula of a functionfεC[0,1] byL m,r f can be represented either by means of divided differences, or in an integral form, obtained by using a classical theorem of Peano. We give also an asymptotic estimate for this remainder. The operatorL m,r enjoys the variation diminishing property—in the sense of I. J. Schoenberg [15]. By extending the known inequalities of T. Popoviciu [12] and G. G. Lorentz [7], we evaluate the orders of approximation in terms of the modulus of continuity of the functionf or of its derivative. In the last section of this paper we determine the point spectrum of the operatorL m,r and , finally, we present a quadrature formula which can be constructed by means of this operator. Dedicated to Professor Aldo Ghizzetti on his 75th birthday  相似文献   
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Transverse susceptibility (TS) method is a reliable method for the determination of anisotropy in nanoparticulate media. To correctly evaluate the value of anisotropy in various modern nanostructured materials, a number of theoretical problems related to the method have to be well understood to avoid significant systematic errors. This paper presents the state of the art in the TS method which includes the expression for single domain particles with any type of anisotropy, the theoretical and micromagnetic, using Landau-Lifshitz-Gilbert (LLG) equation and stochastic LLG equation studies of the effects of ac field amplitude, inter-particle interactions, and magnetic relaxation. The problem of both real and imaginary parts of the TS signal is also discussed.  相似文献   
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An innovative sequential plasma deposition method suitable for deposition of carbon/metal nanocomposite or multilayer films is presented. The method is based on cyclic exposure of a substrate, for predefined time intervals, to two totally independent plasma deposition sources, working in alternative sequences: magnetron sputtering (MS) for metal deposition and Plasma Enhanced Chemical Vapor Deposition (PECVD) for hydrogenated amorphous carbon (a-C:H) deposition. This paper presents a study of the a-C:H/W nanocomposite deposition method by optical emission spectroscopy (OES), focusing on identifying the useful wavelengths for optical monitoring of the process. On the basis of optical monitoring, the optimal pumping out and precursor gas admission conditions are established.  相似文献   
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