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521.
Gianazza E Wait R Begum S Eberini I Campagnoli M Labò S Galliano M 《Proteomics. Clinical applications》2007,1(2):167-175
This report presents a proteomic analysis and provides a reference map of the 5-50-kDa components of normal amniotic fluid collected in gestational weeks 16-18. Early amniocentesis samples were pooled and proteins with molecular mass lower than albumin were separated by gel filtration chromatography. The 2-DE protocol was optimized for the separation of the small proteins and peptides in the fraction of interest. A total of 132 Coomassie blue-stained protein spots were analyzed, following in-gel tryptic digestion, by ESI-MS/MS and 49 different gene products were identified. The treatment with alkaline phosphatase caused the shift of the phosphoisoforms of insulin-like growth factor-binding protein-1 and of the N-terminal osteopontin fragment. Of the 33 full-length proteins identified in the 2-DE profile, 23 had not been previously detected in the amniotic fluid and, of these, 22 are not present in the human plasma proteome under physiological conditions. Fragments of 16 larger proteins were identified and the sequence coverage data revealed that several correspond to autonomous domains that may have biological roles on their own. Several of the detected proteins and peptides appear to be involved in critical regulatory processes associated with placentation and early development, thus representing potential markers of various physiological or pathological conditions. 相似文献
522.
The flexible structure of the mixed logit (ML) model is at the root of the difficulties associated to its estimation. Major problems are parameter identification and the distinction between different substitution patterns. In this paper we focus on the empirical identification problem and investigate the effect of low information richness in the data on the capability of estimating a correct ML model (i.e. with identifiable parameters and free of confounding effects). In particular, we analyse to which extent the empirical identification problem depends on the variability of the data among alternatives, on the degree of heterogeneity of the taste parameters, on the dimension of the sample and on the number of choice tasks for each individual. To test for information richness of the data and its effect on the capability of the ML model to reproduce random heterogeneity in tastes, a collection of datasets was generated varying systematically (a) the standard deviation (SD) of the distribution of travel time differences between the two alternatives, (b) the SD of the random parameter, (c) the number of choice tasks for each individual and (d) the number of individuals in relation to the number of choice tasks. Then, several ML models allowing for random travel time parameters were estimated using different number of draws and results were compared in terms of model goodness of fit and, also, on the capability of reproducing the real parameters used to generate each dataset. Our results suggest that identification problems depend only on the (low) variability of the associated data and disappear as the richness of the data associated to the random parameter increases. However, rich enough data only allows obtaining good statistics but the estimated parameters do not always reproduce the correct values, as the capability of the ML to reproduce random heterogeneity depends on the random parameter distribution (degree of variability and symmetry). Moreover, the capability of the ML to reproduce random heterogeneity increases when more than one choice is available for each individual and the effect of sample size on the empirical identification reduces considerably. 相似文献
523.
In this note we consider the numerical evaluation of one dimensional Cauchy principal value integrals of the form $$\rlap{--} \smallint _a^b \frac{{k(x)f(x)}}{{x - \lambda }}dx, a< \lambda< b,$$ by rules obtained by “subtracting out” the singularity and then applying product quadratures based on cubic spline interpolation at equally spaced nodes. Convergence results are established for Hölder continuous functions of order, μ, 0<μ≤1, and asymptotic rates are obtained for functionsf≠C k [a, b],k=1, 2, 3 or 4. Some comparisons with other methods and numerical examples are also given. 相似文献
524.
Marco Bencivenni Diego Michelotto Roberto Alfieri Riccardo Brunetti Andrea Ceccanti Daniele Cesini Alessandro Costantini Enrico Fattibene Luciano Gaido Giuseppe Misurelli Elisabetta Ronchieri Davide Salomoni Paolo Veronesi Valerio Venturi Maria Cristina Vistoli 《Journal of Grid Computing》2015,13(2):159-175
525.
Zoobia Ameer Anna Grazia Monteduro Silvia Rizzato Anna Paola Caricato Maurizio Martino I. C. Lekshmi Abhijit Hazarika Debraj Choudhury Elisabetta Mazzotta Cosimino Malitesta Vittorianna Tasco D. D. Sarma Giuseppe Maruccio 《Journal of Materials Science: Materials in Electronics》2018,29(9):7090-7098
The increasing constraints in the miniaturization of modern electronic devices is driving the search for new high-k dielectric materials. Rare-earth transition metal oxides are very interesting because of the large values of dielectric constant observed in bulk samples. Here, we report on a comparison among the dielectric properties of yttrium copper titanate (YCTO) thin films and those of commonly used dielectrics such as SiO2 and MgO, grown in similar device structures. The YCTO permittivity was found to depend strongly on the oxygen pressure during deposition and can reach values even higher than those reported in bulk YCTO with good performances in terms of losses. 相似文献
526.
Piek Vossen Laura Bloksma Antonietta Alonge Elisabetta Marinai Carol Peters Irene Castellon Antonia Marti German Rigau 《Computers and the Humanities》1998,32(2-3):153-184
This paper describes how the Euro WordNet project established a maximum level of consensus in the interpretation of relations, without loosing the possibility of encoding language-specific lexicalizations. Problematic cases arise due to the fact that each site re-used different resources and because the core vocabulary of the wordnets show complex properties. Many of these cases are discussed with respect to language internal and equivalence relations. Possible solutions are given in the form of additional criteria. 相似文献
527.
The transition from a planned economy to a market economy has caused considerable hardship for the people of Eastern Europe. One important aspect of the social costs of transition is access to, and the affordability of, basic services like electricity, heat and water, which under communism had been supplied fairly cheaply and abundantly. This paper provides evidence on this issue from the Ukraine Longitudinal Monitoring Survey (ULMS). The paper identifies considerable differences in both access and affordability between different localities in Ukraine. 相似文献
528.
Marco Faimali Elisabetta Chelossi Francesca Garaventa Christian Corrà Giuliano Greco Alfonso Mollica 《Electrochimica acta》2008,54(1):148-153
The aim of a series of works recently performed at ISMAR was to provide new useful information for a better understanding of the mechanisms by which bacteria settlement causes corrosion on Stainless Steels (SS) and similar active-passive alloys exposed to seawater. In this work, the evolutions of cathodic current, bacteria population, and electronic structure of the passive layer were investigated on SS samples polarised at fixed potentials during their exposure to natural seawater. It was found that, during the first phase of biofilm growth, cathodic current increase is proportional to the number of settled bacteria at each fixed potential. However, the proportionality factor between settled bacteria and cathodic current depends on imposed potential. In particular, the proportionality factor strongly decreases when the potential is increased above a critical value close to −150 mV Ag/AgCl. This effect seems to be correlated with the electronic structure of the passive layer. Indeed, the outer part of the passive layer on tested SS was found to behave like a conductor at potentials more active than −150 mV Ag/AgCl, and like an n-type semiconductor at more noble potentials. 相似文献
529.
Alessandra Mingione Francesca Pivari Nicoletta Plotegher Michele Dei Cas Aida Zulueta Tommaso Bocci Marco Trinchera Elisabetta Albi Vittorio Maglione Anna Caretti Luigi Bubacco Rita Paroni Daniele Bottai Riccardo Ghidoni Paola Signorelli 《International journal of molecular sciences》2021,22(12)
Parkinson’s disease (PD) is a proteinopathy associated with the aggregation of α-synuclein and the formation of lipid–protein cellular inclusions, named Lewy bodies (LBs). LB formation results in impaired neurotransmitter release and uptake, which involve membrane traffic and require lipid synthesis and metabolism. Lipids, particularly ceramides, are accumulated in postmortem PD brains and altered in the plasma of PD patients. Autophagy is impaired in PD, reducing the ability of neurons to clear protein aggregates, thus worsening stress conditions and inducing neuronal death. The inhibition of ceramide synthesis by myriocin (Myr) in SH-SY5Y neuronal cells treated with preformed α-synuclein fibrils reduced intracellular aggregates, favoring their sequestration into lysosomes. This was associated with TFEB activation, increased expression of TFEB and LAMP2, and the cytosolic accumulation of LC3II, indicating that Myr promotes autophagy. Myr significantly reduces the fibril-related production of inflammatory mediators and lipid peroxidation and activates NRF2, which is downregulated in PD. Finally, Myr enhances the expression of genes that control neurotransmitter transport (SNARE complex, VMAT2, and DAT), whose progressive deficiency occurs in PD neurodegeneration. The present study suggests that counteracting the accumulation of inflammatory lipids could represent a possible therapeutic strategy for PD. 相似文献
530.
Elisabetta Rubini Marco Minacori Giuliano Paglia Fabio Altieri Silvia Chichiarelli Donatella Romaniello Margherita Eufemi 《International journal of molecular sciences》2021,22(11)
Organochlorine pesticides constitute the majority of the total environmental pollutants, and a wide range of compounds have been found to be carcinogenic to humans. Among all, growing interest has been focused on β-hexachlorocyclohexane (β-HCH), virtually the most hazardous and, at the same time, the most poorly investigated member of the hexachlorocyclohexane family. Considering the multifaceted biochemical activities of β-HCH, already established in our previous studies, the aim of this work is to assess whether β-HCH could also trigger cellular malignant transformation toward cancer development. For this purpose, experiments were performed on the human normal bronchial epithelium cell line BEAS-2B exposed to 10 µM β-HCH. The obtained results strongly support the carcinogenic potential of β-HCH, which is achieved through both non-genotoxic (activation of oncogenic signaling pathways and proliferative activity) and indirect genotoxic (ROS production and DNA damage) mechanisms that significantly affect cellular macroscopic characteristics and functions such as cell morphology, cell cycle profile, and apoptosis. Taking all these elements into account, the presented study provides important elements to further characterize β-HCH, which appears to be a full-fledged carcinogenic agent. 相似文献