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61.
This paper presents a statistical approach based on the k-means clustering technique to manage environmental sampled data to evaluate and to forecast of the energy deliverable by different renewable sources in a given site. In particular, wind speed and solar irradiance sampled data are studied in association to the energy capability of a wind generator and a photovoltaic (PV) plant, respectively. The proposed method allows the sub-sets of useful data, describing the energy capability of a site, to be extracted from a set of experimental observations belonging the considered site. The data collection is performed in Sicily, in the south of Italy, as case study. As far as the wind generation is concerned, a suitable generator, matching the wind profile of the studied sites, has been selected for the evaluation of the producible energy. With respect to the photovoltaic generation, the irradiance data have been taken from the acquisition system of an actual installation. It is demonstrated, in both cases, that the use of the k-means clustering method allows data that do not contribute to the produced energy to be grouped into a cluster, moreover it simplifies the problem of the energy assessment since it permits to obtain the desired information on energy capability by managing a reduced amount of experimental samples. In the studied cases, the proposed method permitted a reduction of the 50% of the data with a maximum discrepancy of 10% in energy estimation compared to the classical statistical approach. Therefore, the adopted k-means clustering technique represents an useful tool for an appropriate and less demanding energy forecast and planning in distributed generation systems.  相似文献   
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LFB1/HNF1 and LFB3/HNF1ß bind DNA as dimers and formheterodimers together in vivo and in vitro. The dimerizationdomain has been located in both proteins in the 32 N-terminalresidues. In previous papers we have described the conformationalstability as determined by CD and the secondary structure byNMR studies of a peptide with the amino acid sequence of thedimerization domain of LFB1/ HNF1. This study presents a morecomplete characterization of similar synthetic peptides spanningthe LFB3/HNF1ß dimerization domain and the /ßheterodimer. The HNF1 peptides represent an example of structureswhich cannot be determined by NOE data alone because they arenot sufficient to define one unique solution. An approach ispresented which combines NMR data, the protein structure databaseand structural analyses according to known principles of proteinstructure. On this basis we are able to determine possible solutionsand to identify a four helix bundle as the structure most consistentwith the experimental evidence.  相似文献   
64.
8-Hydroxyquinoline-5-sulphonate/Al(III) aqueous solutions were studied both by potentiometric titrations and voltammetric measurements, in order to obtain the number, the stoichiometry and the stability constants of the complexes formed at equilibrium, and to evaluate the redox and (electro)kinetic properties of the free ligand and of the metal/ligand complexes. The complexes formed in 0.2 m (Na)Cl aqueous solution (stability log beta values ± standard deviation) are AlL+ (8.95 ± 0.05), AlL2 (17.43 ± 0.03) and AlL33− (24.58 ± 0.05), where “L” denotes the free ligand in the completely deprotonated form (L2−, pKa1 = 3.910 ± 0.008, pKa2 = 8.319 ± 0.004). AlL33− is the predominant Al(III) species in a very wide range of pH, metal and ligand concentrations and metal-to-ligand ratios. The free ligand shows an oxidation wave at 0.62 V versus SCE. The proposed oxidation mechanism includes a first reversible one-electron oxidation of the ligand, followed by a coupling reaction and by a second reversible one-electron oxidation, and finally by a decomposition reaction. The addition of Al(III) lowers the intensity of the oxidation wave due to the formation of the redox-inactive complex AlL33−. A residual low signal was attributed to the free ligand produced by the complex dissociation, AlL33− = AlL2 + L2−. All the kinetic parameters involved in the ligand oxidation and in the complex disruption were calculated on the basis of the agreement between experimental and simulated linear sweep and cyclic voltammetries. Correctness of the mechanisms proposed was further confirmed “a posteriori” by the agreement between potentiometric and linear sweep voltammetric results. The low residual signal observed in the presence of fully formed complex was attributed to the free ligand produced by the complex dissociation, having a kinetic constant estimated 0.2 s−1.  相似文献   
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A deep study on the possibility to increase the quality of the dispersion of organically modified Boehmite nanoparticles into photo‐polymerizable methacrylic‐siloxane monomers, to be used as coatings, was conducted using unconventional indirect analyses. The nanocomposite were produced using two different procedures, starting from the conventional “solvent dispersion method.” The two procedures used differ for the technique used to obtain the dispersion of Boehmite, i.e., sonication or magnetic stirring and for the time used in each procedure. The efficiency of each method of preparation of nanostructured systems was analyzed, both in the liquid (uncured) and ultraviolet (UV) cured state. First, dynamic light scattering and rheological measurements were performed on the liquid suspensions, supplying experimental data used in proper theoretical models to estimate the dimensions and distribution of Boehmite particles. The suspensions obtained with the two different methods were, then, UV cured obtaining thin and thick films, on which scanning electron microscopy and transmittance measurements were performed. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
67.
Intracellular glycans in the urothelium of urinary bladder of 10 adult male Landrace pigs were characterized in situ by immunohistochemical detection of Muc1 mucin by anti MUC1 from rabbit, conventional histochemical techniques (Periodic‐Acid Schiff, Alcian Blue pH 2.5, High‐Iron Diamine), and binding with 13 lectins (PNA, DBA, RCA‐I, WGA, SBA, BSI‐B4, ConA, AAA, UEA‐I, LTA, LFA, MAA‐II, SNA) combined with chemical and enzymatic pre‐treatments (β‐elimination, desulfation and neuraminidase) to gather reference data for this model animal. Muc1 mucin was detected in the secreting granules of superficial cells and the underlying layer of intermediate cells. The secreting granules in both intermediate cells and superficial cells were rich in carbohydrates, with the oligosaccharidic chains mostly O‐linked to proteins. Glycoproteins were prevailing over glycosaminoglycans (GAGs). In both superficial and intermediate cells sulfated and/or sialylated glycans were present, sulfation decreasing in the deeper layers. Lectin‐binding detected presence of terminal sialic acid linked mostly in α2,6 to GalNAc, Gal terminal or subterminal to sulfates, GalNAc, GlcNAc, and Fuc, mostly linked in α1,6, α1,3 α1,4 and α1,2 to GlcNAc or Gal, but not to lactosamine chains. Except for fucosylation, the oligosaccharidic chains in the glycoproteins of the urothelium of pig urinary bladder were similar to those linked to human MUC1, which is fundamental in cell adhesion and immunological processes in the urothelium. The co‐distribution of Muc1 and saccharidic residues suggests that many of them are linked to the glycoprotein.  相似文献   
68.
Electrically conductive fabrics were produced by deposition of a thin film of doped polypyrrole on the surface of cotton fibres. In situ oxidative chemical polymerisation were carried out in aqueous solutions of pyrrole, oxidant and doping agents, at room temperature. Polypyrrole-coated fibres were characterized by Light Microscopy, SEM, EDX, FTIR and TGA. Moreover, fabric samples were also evaluated for moisture regain, electrical resistivity, heat generation and antibacterial activity. PPy alters the combustion process of cellulose fibres that maintain the fibrous shape after heating in air. Moreover, it seems that PPy is really an antibacterial agent, apart from the oxidant or dopant used. The results highlight potential applications as technical textiles with antistatic (low electrical resistance), heat generation, hygroscopy, antibacterial and high temperature resistance properties.  相似文献   
69.
We connect in a grid-enabled pipeline an ontology-based environment for proteomics spectra management with a machine learning platform for unbiased predictive analysis. We exploit two existing software platforms (MS-Analyzer and BioDCV), the emerging proteomics standards, and the middleware and computing resources of the EGEE Biomed VO grid infrastructure. In the setup, BioDCV is accessed by the MS-Analyzer workflow as a Web service, thus providing a complete grid environment for proteomics data analysis. Predictive classification studies on MALDI-TOF data based on this environment are presented.  相似文献   
70.
Currently,sorafenib is the only systemic therapy capable of increasing overall survival of hepatocellular carcinoma patients.Unfortunately,its side effects,particularly its overall toxicity,limit the therapeutic response that can be achieved.Superparamagnetic iron oxide nanoparticles (SPIONs) are very attractive for drug delivery because they can be targeted to specific sites in the body through application of a magnetic field,thus improving intratumoral accumulation and reducing adverse effects.Here,nanoformulations based on polyethylene glycol modified phospholipid micelles,loaded with both SPIONs and sorafenib,were successfully prepared and thoroughly investigated by complementary techniques.This nanovector system provided effective drug delivery,had an average hydrodynamic diameter of about 125 nm,had good stability in aqueous medium,and allowed controlled drug loading.Magnetic analysis allowed accurate determination of the amount of SPIONs embedded in each micelle.An in vitro system was designed to test whether the SPION micelles can be efficiently held using a magnetic field under typical flow conditions found in the human liver.Human hepatocellular carcinoma (HepG2) cells were selected as an in vitro system to evaluate tumor cell targeting efficacy of the superparamagnetic micelles loaded with sorafenib.These experiments demonstrated that this delivery platform is able to enhance sorafenib's antitumor effectiveness by magnetic targeting.The magnetic nanovectors described here represent promising candidates for targeting specific hepatic tumor sites,where selective release of sorafenib can improve its efficacy and safety profile.  相似文献   
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