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71.
Alessandra Orsoni 《国际通用系统杂志》2013,42(5):619-635
This paper characterizes the development of a hybrid computer-based tool supporting design for safety practices in industrial plant component specification and layout definition. The tool combines simulation and fuzzy logic techniques for the systematic risk assessment of specified design and layout configurations for plants dealing with hazardous materials. In the hybrid system architecture, the simulation module provides the historical experience for a priori hazard identification and ranking, accounting for the domino effects of possible accidental occurrences, while the fuzzy module provides the correlation matrices for concurrent hazard evaluation and overall risk assessment. In particular, the fuzzy module enables the quantitative assessment and comparison among alternative design solutions providing design guidelines, which can be further tested and verified through simulation. 相似文献
72.
Chiara Renghini Alessandra Giuliani Serena Mazzoni Francesco Brun Emanuel Larsson Francesco Baino Chiara Vitale-Brovarone 《Journal of the European Ceramic Society》2013,33(9):1553-1565
One of the key purposes of bone tissue engineering is the development of new biomaterials that can stimulate the body's own regenerative mechanism for patient's anatomical and functional recovery. Bioactive glasses, due to their versatile properties, are excellent candidates to fabricate porous 3-D architectures for bone replacement. In this work, morphological and structural investigations are carried out on Bioglass®- and CEL2-derived scaffolds produced by sponge replication (CEL2 is an experimental glass developed at Politecnico di Torino). Synchrotron radiation X-ray microtomography is used to study the samples 3-D architecture, pores size, shape, distribution and interconnectivity, as well as the growth kinetics on scaffolds struts of a newly formed apatitic phase during in vitro treatment in simulated body fluid, in order to describe from a quantitative viewpoint the bioactive potential of the analyzed biomaterials. An accurate comparison between architectural features and bioactive behaviour of Bioglass®- and CEL2-derived scaffolds is presented and discussed. 相似文献
73.
Dr. Alessandra Ammazzalorso Dr. Barbara De Filippis Dr. Letizia Giampietro Prof. Rosa Amoroso 《ChemMedChem》2013,8(10):1609-1616
Peroxisome proliferator‐activated receptors (PPARs) have been studied extensively over the last few decades and have been assessed as molecular targets for the development of drugs against metabolic disorders. A rapid increase in understanding of the physiology and pharmacology of these receptors has occurred, together with the identification of novel chemical structures that are able to activate the various PPAR subtypes. More recent evidence suggests that moderate activation of these receptors could be favorable in pathological situations due to a decrease in the side effects brought about by PPAR agonists. PPAR partial agonists and antagonists are interesting tools that are currently used to better elucidate the biological processes modulated by this family of nuclear receptors. Herein we present an overview of the various molecular structures that are able to block each of the PPAR subtypes, with a focus on promising therapeutic applications. 相似文献
74.
75.
Nicoletta Sinelli Lorenzo Cerretani Valentina Di Egidio Alessandra Bendini Ernestina Casiraghi 《Food research international (Ottawa, Ont.)》2010,43(1):369-375
A sensory analysis of 112 virgin olive oils was performed by a fully trained taste panel. The samples were divided in “defective” and “not defective” on the basis of their olfactory attributes. Then, the “not defective” samples were classified into “low”, “medium” and “high” according to the fruity aroma intensity perceived by assessors. All samples were also analysed by FT-NIR and FT-IR spectroscopy and processed by classification methods (LDA and SIMCA). The results showed that NIR and MIR spectroscopy coupled with statistical methods are an interesting technique compared with traditional sensory assessment in classifying olive oil samples on the basis of the fruity attribute. The prediction rate varied between 71.6% and 100%, as average value. The spectroscopic methods, combined with chemometric strategies, could represent a reliable, cheap and fast classification tool, able to draw a complete fingerprint of a food product, describing its intrinsic quality attributes, that include its sensory attributes. 相似文献
76.
77.
Alessia Cao Alessandra Carucci Tiziana Lai Gianluigi Bacchetta Mauro Casti 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(6):884-889
BACKGROUND: The application of phytostabilization and assisted phytoextraction to the remediation of abandoned mining areas can be a valuable method to reclaim these areas without modifying soil and landscape characteristics. An in situ application of a continuous phytoextraction technique was carried out in the area of Campo Pisano (Sardinia, Italy), followed by a laboratory assisted phytoextraction test using the biodegradable chelating agents methylglycine diacetic acid (MGDA) and iminodissuccinic acid (IDSA). The plants used were Scrophularia canina subsp. bicolor, Cistus salviifolius and Teucrium flavum subsp. glaucum. RESULTS: The plant that accumulated more Pb was T. glaucum (353 mg kg?1) while C. salviifolius demonstrated better ability to accumulate Zn (1560 mg kg?1). S. bicolor showed a better tolerance to metals but accumulated 119 mg kg?1 of Pb. Accumulation of metals immediately after chelant application was up to 300 mg kg?1 of Pb and 3000 mg kg?1 of Zn which did not further increase during the assisted phytoextraction experiment. CONCLUSION: The plant that demonstrated to be most suitable for phytoremediation application was S. bicolor due to its higher biomass production and tolerance to metals. The low cation exchange capacity and the high concentration of Ca and Mg in soil determined a low chelant effectiveness. Copyright © 2009 Society of Chemical Industry 相似文献
78.
Sabrina Burattini Paola Ferri Michela Battistelli Alessandra D'emilio Laura Biagiotti Piero Sestili Marco B. L. Rocchi Elisabetta Falcieri 《Microscopy research and technique》2009,72(12):913-923
A common pattern of apoptotic death is DNA cleavage, initially producing large fragments (50 kbp), followed by the production of nucleosomic/oligonucleosomic fragments. Nevertheless, apoptosis without DNA fragmentation, at least of the nucleosomic type, has been reported. To investigate the spatial relationship between DNA cleavage and chromatin condensation, we applied the TUNEL technique to the ultrastructural analysis of apoptotic cells. A modified method, utilizing a gold‐conjugated antidigoxigenin antibody, was carried out on U937 versus Molt‐4 cells, both exposed to UVB radiation or staurosporine treatment. Gold particle density in the different domains of apoptotic cells was evaluated by a four‐way ANOVA test. Gold labelling was more strongly localised in condensed chromatin than in the diffuse chromatin. U937 cells, which evidenced in vitro oligonucleosomic fragmentation after both UVB and staurosporine treatments, revealed a significantly higher gold particle density, when compared with Molt‐4, which did not show, on the other hand, oligonucleosomic cleavage even in the presence of ≤50 kbp cleavage. Thus, a correlation between DNA fragment sizes and gold particle density appears. TUNEL applied to electron microscopy is an effective approach to study the relationship between apoptotic chromatin condensation and DNA cleavage. Both these events indeed appear in the apoptotic nucleus, but their reciprocal correlation is still greatly unknown. Microsc. Res. Tech. 2009. © 2009 Wiley‐Liss, Inc. 相似文献
79.
In recent years, the growing attention to environmental challenges has shown that these issues are becoming of more and more interest to both research and industry. Companies are expected to ensure their products are fully traceable and more sustainable, which requires the involvement of all of the actors in the production network. According to this aim, this study proposes a structured approach that uses the traditional traceability concept as a means to identify the main information needed to assess environmental impacts along the whole supply chain (SC). The proposed approach is composed of four main steps: (i) SC modelling to identify all stakeholders and their inter-relations, (ii) data sharing to collect all relevant data, (iii) data elaboration to calculate performance at different levels of detail and (iv) result interpretation to optimise the SC. The distributed implementation of the approach at different SC steps represents a useful means to practically realise a sustainable SC management. A case study involving a leather shoe SC is used to demonstrate the effectiveness of the approach in identifying criticalities, supporting the selection of the most appropriate suppliers and correctly setting a management strategy towards the optimisation of internal and external traceability and environmental sustainability performances. 相似文献
80.
Giacomo Veneri Pamela Federighi Francesca Rosini Antonio Federico Alessandra Rufa 《Computers in human behavior》2010
We describe an interactive gaze-contingent display (GCD) applied to clinical applications; the system uses a simple texture hole to inhibit peripheral vision, to test and stress overt mechanisms of visual searching in normal subjects. The correct use of GCD in vision research is affected by tremor of the hole, due to system noise, nystagmus, eye blinking, calibration and subject reactivity. These issues compromise the execution of task. In order to obtain a stable GCD hole, we implemented a predictive gaze-contingent display (PGCD), fitting through dispersion of fixations and modulating a filter. The paper describes the PGCD and compare it with the common technique, providing evidence that humans fit exploration based on the characteristics of the computer system; in particular we found significant difference applying PGCD or a simple finite impulse response filter. We suggest that a correct human–computer interaction applied to neuropsychological context must be developed taking in consideration both technical point of view and human behavior. 相似文献