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排序方式: 共有2030条查询结果,搜索用时 234 毫秒
941.
Franco Cicirelli Author Vitae Author Vitae Libero Nigro Author Vitae 《Journal of Systems and Software》2010,83(7):1148-1164
In the last few years, business process management systems have been employed for handling information systems of ever increasing complexity. As a consequence, the adoption of modelling languages enabling smooth and seamless transitions among the various phases of the process lifecycle, the ability of exploiting coordination schema over distributed execution contexts and the support for dynamic evolution and reconfiguration have become software engineering issues of great importance. This paper proposes the use of PN-Engine, a decentralized Petri nets execution engine, as a business process enactment engine. PN-Engine, which is based on the Jini service architecture, supports the decentralized execution of process models specified as Petri nets (PNs) enhanced with modular constructs and offers suitable mechanisms for dealing with the aforementioned design issues. PN-Engine allows to deploy and enact a new version of an existing process model without requiring the stopping/removal of older instances that are still running. The paper presents a novel approach enabling a decentralized migration procedure where concurrent portions of older instances migrate asynchronously to the new process model. Advantages of the proposed approach are demonstrated by means of an example concerning a workflow for a wine-production process. 相似文献
942.
Laura Maria De Plano Domenico Franco Maria Giovanna Rizzo Vincenzo Zammuto Concetta Gugliandolo Letteria Silipigni Lorenzo Torrisi Salvatore P. P. Guglielmino 《International journal of molecular sciences》2021,22(7)
The conformational variation of the viral capsid structure plays an essential role both for the environmental resistance and acid nuclear release during cellular infection. The aim of this study was to evaluate how capsid rearrangement in engineered phages of M13 protects viral DNA and peptide bonds from damage induced by UV-C radiation. From in silico 3D modelling analysis, two M13 engineered phage clones, namely P9b and 12III1, were chosen for (i) chemical features of amino acids sequences, (ii) rearrangements in the secondary structure of their pVIII proteins and (iii) in turn the interactions involved in phage capsid. Then, their resistance to UV-C radiation and hydrogen peroxide (H2O2) was compared to M13 wild-type vector (pC89) without peptide insert. Results showed that both the phage clones acquired an advantage against direct radiation damage, due to a reorganization of interactions in the capsid for an increase of H-bond and steric interactions. However, only P9b had an increase in resistance against H2O2. These results could help to understand the molecular mechanisms involved in the stability of new virus variants, also providing quick and necessary information to develop effective protocols in the virus inactivation for human activities, such as safety foods and animal-derived materials. 相似文献
943.
944.
Federica Lince Sara Bolognesi Barbara Stella Daniele L. Marchisio Franco Dosio 《Chemical Engineering Research and Design》2011,89(11):2410-2419
The preparation of polymer nanoparticles loaded with an active principle, commonly used in cancer treatment, is investigated here from the experimental point of view. The main novelty of this work stands in the use of continuous confined impinging jets mixers in combination with realistic materials, notably the biodegradable and biocompatible copolymer poly(methoxypolyethyleneglycolcyanoacrylate-co-hexadecylcyanoacrylate) together with two forms of the drug doxorubicin. To our knowledge this is the first attempt to use for such a system a device that can be operated continuously and can be easily scaled up. Nanoparticles are produced via solvent-displacement experimenting different solvents; the effect of the other operating parameters is also investigated. Nanoparticles are characterized in terms of their size distribution and surface properties; for a limited number of samples prepared with the optimized preparation protocol further characterization (in terms of drug loading, incorporation and release profiles) is also carried out. Collected results show that the overall approach is capable of producing nanoparticles with controlled particle size distribution, drug loading and good reproducibility and that on the contrary of what reported in the literature the presence of the active principle does play an important role. 相似文献
945.
Marcio Vargas-Ramella Rubén Domínguez Mirian Pateiro Daniel Franco Francisco J. Barba José M. Lorenzo 《International Journal of Food Science & Technology》2020,55(3):1025-1031
The changes on chemical composition, physico-chemical parameters, free fatty acids and free amino acids content of dry-cured deer loin were investigated at day 0, 30 and 60 of dry-cured process. On the whole, except for pH values (≈5.6) and composition (fat: 4.6–5.2%; protein: ≈73%; ash: ≈17.5%) that did not show differences between the processing days, the other physico-chemical parameters were affected by curing process. Colour parameters and moisture (from 69 to 38.4%) decreased while the hardness increase from 12.35 to 342 N and lipid oxidation (from 0.2 to 0.52 mg MDA/kg) increased as dry-cured stage progresses. In similar way, free fatty acid (2250 mg per 100 g of fat at 0 day and 5940 mg per 100 g of fat at 60 days) and free amino acid content (914 mg per 100 g DM at 0 day and 1253 mg per 100 g DM at 60 days) increased progressively as the curing process progressed. The behaviour of this product during processing is similar to that described for the same product made with other animal species. Therefore, deer meat is an excellent candidate for the production of dry-cured loin, which would allow introducing a new product on the market. 相似文献
946.
Pietro Paolo Corso Gianfranco orlando Franco Persico 《Journal of Modern Optics》2013,60(10):1387-1393
The dynamics of a homonuclear diatomic molecule driven by a laser pulse is obtained beyond the fixed nuclei approximation. Laser parameters can be adjusted to confine the electron over one of the two nuclei for a relatively long time or not. A time-resolved analysis of the electromagnetic spectrum emitted by the molecule presents the usual odd harmonics far from confinement and even harmonics during the confinement periods. A physical interpretation of the results is given. 相似文献
947.
A municipal landfill leachate was treated only with ozone, only with activated carbon and by a combined action of activated carbon and ozone. It is shown that the best results in terms of COD (Chemical Oxygen demand) reduction, color improvement, removal of the transition metals and final sterilization of the treated water derived from the leachate can be achieved by combining the activated carbon treatment with the ozonolysis, reserving the latter as the final step of the treatment so that the water from leachate is produced completely sterilized. The COD can be brought down to less than 10% of the starting value found in the pristine leachate together with a complete removal of the transition metals and the best possible color improvement from the original brown and turbid of the pristine leachate to the water-white color of the resulting purified water. 相似文献
948.
Complexity and anisotropy in host morphology make populations less susceptible to epidemic outbreaks
Francisco J. Pérez-Reche Sergei N. Taraskin Luciano da F. Costa Franco M. Neri Christopher A. Gilligan 《Journal of the Royal Society Interface》2010,7(48):1083-1092
One of the challenges in epidemiology is to account for the complex morphological structure of hosts such as plant roots, crop fields, farms, cells, animal habitats and social networks, when the transmission of infection occurs between contiguous hosts. Morphological complexity brings an inherent heterogeneity in populations and affects the dynamics of pathogen spread in such systems. We have analysed the influence of realistically complex host morphology on the threshold for invasion and epidemic outbreak in an SIR (susceptible–infected–recovered) epidemiological model. We show that disorder expressed in the host morphology and anisotropy reduces the probability of epidemic outbreak and thus makes the system more resistant to epidemic outbreaks. We obtain general analytical estimates for minimally safe bounds for an invasion threshold and then illustrate their validity by considering an example of host data for branching hosts (salamander retinal ganglion cells). Several spatial arrangements of hosts with different degrees of heterogeneity have been considered in order to separately analyse the role of shape complexity and anisotropy in the host population. The estimates for invasion threshold are linked to morphological characteristics of the hosts that can be used for determining the threshold for invasion in practical applications. 相似文献
949.
Rosilene L. Dutra Karen Segala Eric M. N. de Oliveira Eduardo P. de Souza Liane M. Rossi Jivaldo R. Matos Lucia K. Noda Marcos M. S. Paula Cesar V. Franco 《Polymer Bulletin》2008,60(6):809-819
This paper reports the preparation and characterization of poly-{trans-[RuCl2(vpy)4-styrene-divinylbenzene}
and styrene-divinylbenzene-vinylpiridine filled with nanosilver. Theses materials were synthesized by
non aqueous polymerization through a chemical reaction using benzoyl peroxide as the initiator. The
nanosilver was obtained from chemical reduction using NaBH4 as reducing agent
and sodium citrate as stabilizer. The nanometric dimension of nanosilver was monitored by UV-visible
and confirmed through TEM. The morphology was characterized by SEM and the thermal properties were done
by TGA and DSC. The antimicrobial action of the polymers impregnated with nanosilver was evaluated using
both microorganisms, Staphylococcus aureus and Escherichia
coli. The antimicrobial activity of the poly-{trans-[RuCl2(vpy)4]-styrene-divinylbenzene}
filled with nanosilver was confirmed by the presence of an inhibition halo of the bacterial growth in
seeded culture media, but was not confirmed to the styrene-divinylbenzene-vinylpiridine. The present
work suggest that trans - [RuCl2(vpy)4] complex facilitate
the release of silver ion from the media. 相似文献
950.
Monica Locatelli Fabiano Travaglia Lorella Giovannelli Jean Daniel Coïsson Matteo Bordiga Franco Pattarino Marco Arlorio 《Food research international (Ottawa, Ont.)》2013,50(1):129-134
Neo-synthesized clovamide and a phenolic cocoa extract (fermented cocoa from Ghana) were evaluated for their capacity to inhibit lipid peroxidation. Their effect was first investigated on phospholipid organic solutions, and then on liposomal systems prepared by high pressure homogenization process. Antioxidants were added to liposomal system following two different protocols (before and after the homogenization treatment) and their protective action was evaluated monitoring the oxidative status of liposomes (exposed to light at room temperature or heated at 40 °C) over three weeks. The results confirmed a significant protective effect of clovamide on liposomal model systems and, in a minor extent, also of cocoa extract. The capacity of phosphatidylcholine liposomes to incorporate clovamide was also evaluated; it was shown that more than 50% of clovamide was englobed in liposomes, although the addition of clovamide solution before the homogenization process led to the isomerization of the molecule from trans to cis form. 相似文献