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101.
Tamariz E Wan AC Pek YS Giordano M Hernández-Padrón G Varela-Echavarría A Velasco I Castaño VM 《Journal of materials science. Materials in medicine》2011,22(9):2097-2109
Chemotropic proteins guide neuronal projections to their final target during embryo development and are useful to guide axons
of neurons used in transplantation therapies. Site-specific delivery of the proteins however is needed for their application
in the brain to avoid degradation and pleiotropic affects. In the present study we report the use of Poly (ethylene glycol)-Silica
(PEG-Si) nanocomposite gel with thixotropic properties that make it injectable and suitable for delivery of the chemotropic
protein semaphorin 3A. PEG-Si gel forms a functional gradient of semaphorin that enhances axon outgrowth of dopaminergic neurons
from rat embryos or differentiated from stem cells in culture. It is not cytotoxic and its properties allowed its injection
into the striatum without inflammatory response in the short term. Long term implantation however led to an increase in macrophages
and glial cells. The inflammatory response could have resulted from non-degraded silica particles, as observed in biodegradation
assays. 相似文献
102.
Marengo E Manfredi M Zerbinati O Robotti E Mazzucco E Gosetti F Bearman G France F Shor P 《Analytical chemistry》2011,83(17):6609-6618
The aim of this project is the development of a noninvasive technique based on LED multispectral imaging (MSI) for monitoring the conservation state of the Dead Sea Scrolls (DSS) collection. It is well-known that changes in the parchment reflectance drive the transition of the scrolls from legible to illegible. Capitalizing on this fact, we will use spectral imaging to detect changes in the reflectance before they become visible to the human eye. The technique uses multivariate analysis and statistical process control theory. The present study was carried out on a "sample" parchment of calfskin. The monitoring of the surface of a commercial modern parchment aged consecutively for 2 h and 6 h at 80 °C and 50% relative humidity (ASTM) was performed at the Imaging Lab of the Library of Congress (Washington, DC, U.S.A.). MSI is here carried out in the vis-NIR range limited to 1 μm, with a number of bands of 13 and bandwidths that range from about 10 nm in UV to 40 nm in IR. Results showed that we could detect and locate changing pixels, on the basis of reflectance changes, after only a few "hours" of aging. 相似文献
103.
Improved CO2 Capture from Flue Gas by Basic Sites,Charge Gradients,and Missing Linker Defects on Nickel Face Cubic Centered MOFs 下载免费PDF全文
Elena López‐Maya Carmen Montoro Valentina Colombo Elisa Barea Jorge A. R. Navarro 《Advanced functional materials》2014,24(39):6130-6135
The adsorptive properties of the isoreticular series [Ni8(OH)4(H2O)2(BDP_X)6] (H2BDP_X = 1,4‐bis(pyrazol‐4‐yl)benzene‐4‐X with X = H (1), OH (2), NH2 (3)) can be enhanced by postsynthetic treatment with an excess of KOH in ethanol. In the case of X = H, NH2, this treatment leads to partial removal of the organic linkers, deprotonation of coordinated water molecules and introduction of extraframework cations, giving rise to materials of K[Ni8(OH)5(EtO)‐(H2O)2(BDP_X)5.5] (1@KOH, 3@KOH) formulation, in which the original framework topology is maintained. By contrast, the same treatment with KOH in the [Ni8(OH)4(H2O)2(BDP_OH)6] (2) system, enclosing the more acidic phenol residues, leads to a new material containing a larger fraction of missing linker defects and extra‐framework cations as well as phenolate residues, giving rise to the material K3[Ni8(OH)3(EtO)(H2O)6(BDP_O)5] (2@KOH), which also conserves the original face cubic centered (fcu) topology. It is noteworthy that the introduction of missing linker defects leads to a higher accessible pore volume with a concomitant increased adsorption capacity. Moreover, the creation of coordinatively unsaturated metal centers, charge gradients, and phenolate nucleophilic sites in 2@KOH gives rise to a boosting of CO2 capture features with increased adsorption heat and adsorption capacity, as proven by the measurement of pulse gas chromatography and breakthrough curve measurements of simulated flue gas. 相似文献
104.
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106.
Michael Ortiz Bahram Nour-Omid Elisa D. Sotelino 《International journal for numerical methods in engineering》1988,26(2):379-391
The accuracy of a new class of concurrent, procedures for transient finite element analysis is examined. A phase error analysis is carried out which shows that wave retardation leading to unacceptable loss of accuracy may occur if a Courant condition based on the dimensions of the subdomains is violated. Numerical tests suggest that this Courant condition is conservative for typical structural applications and may lead to a marked increase in accuracy as the number of subdomains is increased. Theoretical speed-up ratios are derived which suggest that the algorithms under consideration can be expected to exhibit a performance superior to that of globally implicit methods when implemented on parallel machines. 相似文献
107.
Long Nicholas; Slater Elisa; Forehand Rex; Fauber Robert 《Canadian Metallurgical Quarterly》1988,56(3):467
Three groups of young adolescent subjects were compared on several measures of adjustment in the school setting. The three groups of subjects included (a) a group from recently divorced families in which high levels of interparental conflict prior to parental separation and after the divorce had been reported, (b) a group from recently divorced families in which high levels of interparental conflict prior to parental separation but low levels after the divorce had been reported, and (c) a comparison group from intact families. Adolescents from the first group were found to be functioning at a lower level than those from the other two groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
A new and efficient protocol to prepare 2-(R-anilino)-1,4-naphthoquinones in quantitative yields is presented. This synthesis occurs under mild conditions by reacting the corresponding aniline and 1,4-naphthoquinone in the presence of a bentonitic clay. The role of the clay is explained in terms of a reaction mechanism in which an activated complex is formed by the reaction of 1,4-naphthoquinone with Lewis acid sites of the clay. Based on the chemical composition of the clay, with Fe3+ sites, the last step of the mechanism is proposed to involve an oxidation-reduction reaction. 相似文献
109.
Elisa?BertinoEmail author Igor?Nai?Fovino Loredana?Parasiliti?Provenza 《Data mining and knowledge discovery》2005,11(2):121-154
Recently, a new class of data mining methods, known as privacy preserving data mining (PPDM) algorithms, has been developed by the research community working on security and knowledge discovery. The aim of these
algorithms is the extraction of relevant knowledge from large amount of data, while protecting at the same time sensitive
information. Several data mining techniques, incorporating privacy protection mechanisms, have been developed that allow one
to hide sensitive itemsets or patterns, before the data mining process is executed. Privacy preserving classification methods,
instead, prevent a miner from building a classifier which is able to predict sensitive data. Additionally, privacy preserving
clustering techniques have been recently proposed, which distort sensitive numerical attributes, while preserving general
features for clustering analysis. A crucial issue is to determine which ones among these privacy-preserving techniques better
protect sensitive information. However, this is not the only criteria with respect to which these algorithms can be evaluated.
It is also important to assess the quality of the data resulting from the modifications applied by each algorithm, as well
as the performance of the algorithms. There is thus the need of identifying a comprehensive set of criteria with respect to
which to assess the existing PPDM algorithms and determine which algorithm meets specific requirements.
In this paper, we present a first evaluation framework for estimating and comparing different kinds of PPDM algorithms. Then,
we apply our criteria to a specific set of algorithms and discuss the evaluation results we obtain. Finally, some considerations
about future work and promising directions in the context of privacy preservation in data mining are discussed.
*The work reported in this paper has been partially supported by the EU under the IST Project CODMINE and by the Sponsors of
CERIAS.
Editor: Geoff Webb
相似文献
Elisa Bertino (Corresponding author)Email: |
Igor Nai FovinoEmail: |
Loredana Parasiliti ProvenzaEmail: |
110.
Carminic acid (CA) is a natural red pigment produced by Dactylopius coccus C. insects. It is widely used in the food industry to replace synthetic colourants. Despite being known for a long time, its antioxidant properties have not been studied so far. The aim of this study was to determine CA activities by different methods namely, free radical scavenging capacity against DPPH and ABTS radicals as well as its inhibition ability of β-carotene bleaching enzymatically induced by lipoxygenase (LOX). CA exhibited a remarkable antiradical activity similar to that of known antioxidants such as quercetin, ascorbic acid and trolox. Effectiveness of CA to protect β-carotene in the co-oxidation with linoleic acid is attributed to enzymatic inhibition of LOX rather than peroxyl radical trapping. 相似文献