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11.
Cristiano J.J. White C.C. Jr. Liker J.K. 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2001,31(3):366-382
In the product design and development process, quality function deployment (QFD) provides a comprehensive, systematic approach to support the design of new products intended to meet or exceed customer expectations. The authors use multiattribute value theory to support new product design and hence to augment a design team's experience and judgment. We introduce the concept of a target set, the set of all value score vectors that are at least as preferred as the value score vectors of any of the given design alternatives. Assuming mutually preferential independence, we characterize the target set and indicate how it can be used to support selecting targets: 1) for the level of customer satisfaction to be attained by the new product, for each customer requirement and 2) for design requirements, presumably based in part on information from engineering competitive assessments. We then use the target set concept to augment the product planning phase of QFD. The concepts are illustrated and evaluated through the retrospective application of the methodology to an actual surgical product (universal converter). Although the analysis was performed retrospectively, without knowledge of the market success of the product and its competitors, the results were consistent with product acceptance and provided valuable insights to the lead engineer 相似文献
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Carolina Gismene Jorge Enrique Hernndez Gonzlez Angela Rocio Nio Santisteban Andrey Fabricio Ziem Nascimento Lucas dos Santos Cunha Fbio Rogrio de Moraes Cristiano Luis Pinto de Oliveira Caio C. Oliveira Paola Jocelan Scarin Provazzi Pedro Geraldo Pascutti Raghuvir Krishnaswamy Arni Ricardo Barros Mariutti 《International journal of molecular sciences》2022,23(17)
Staphylococcal exfoliative toxins (ETs) are glutamyl endopeptidases that specifically cleave the Glu381-Gly382 bond in the ectodomains of desmoglein 1 (Dsg1) via complex action mechanisms. To date, four ETs have been identified in different Staphylococcus aureus strains and ETE is the most recently characterized. The unusual properties of ETs have been attributed to a unique structural feature, i.e., the 180° flip of the carbonyl oxygen (O) of the nonconserved residue 192/186 (ETA/ETE numbering), not conducive to the oxyanion hole formation. We report the crystal structure of ETE determined at 1.61 Å resolution, in which P186(O) adopts two conformations displaying a 180° rotation. This finding, together with free energy calculations, supports the existence of a dynamic transition between the conformations under the tested conditions. Moreover, enzymatic assays showed no significant differences in the esterolytic efficiency of ETE and ETE/P186G, a mutant predicted to possess a functional oxyanion hole, thus downplaying the influence of the flip on the activity. Finally, we observed the formation of ETE homodimers in solution and the predicted homodimeric structure revealed the participation of a characteristic nonconserved loop in the interface and the partial occlusion of the protein active site, suggesting that monomerization is required for enzymatic activity. 相似文献
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Janaina Braga do?CarmoEmail author Christopher?Neill Diana?C.?Garcia-Montiel Marisa?de Cássia Piccolo Carlos?C.?Cerri Paul?A.?Steudler Cristiano Alberto?de Andrade Caio?C.?Passianoto Brigitte?J.?Feigl Jerry?M.?Melillo 《Nutrient Cycling in Agroecosystems》2005,71(3):213-225
The clearing of tropical rain forest in the Amazon basin has created large areas of cattle pasture that are now declining in productivity. Practices adopted by ranchers to restore productivity to degraded pastures have the potential to alter soil N availability and gaseous N losses from soils. We examined how soil inorganic N pools, net N mineralization and net nitrification rates, nitrification potential and NO and N2O emissions from soils of a degraded pasture responded to the following restoration treatments: (1) soil tillage followed by replanting of grass and fertilization, (2) no-till application of non-selective herbicide, planting of rice, harvest followed by no-till replanting of grass and fertilization, and (3) the same no-till sequence with soybeans instead of rice. Tillage increased soil NH4+ and NO3? pools but NH4+ and NO3? pools remained relatively constant in the control and no-till treatments. Cumulative rates of net N mineralization and net nitrification during the first 6 months after treatment varied widely but were hightest in the tilled treatment. Emissions of NO and N2O fluxes increased with tillage and with N fertilization. There were no clear relationships among rates of N fertilizer application, net N mineralization, net nitrification, NO, N2O and total N oxide emissions. Our results indicate that pasture restoration sequences involving tilling and fertilizing will increase emissions of N oxides, but the magnitude of the increase is likely to differ based on timing of fertilizer application relative to the presence of plants and the magnitude of plant N demand. Emissions of N oxides appear to be decreased by the use of restoration sequences that minimize reductions in pasture grass cover. 相似文献
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Rafael A. Amaral Cristiano P. Borges Alberto C. Habert Nicolas R. J.‐D. Mermier 《化学工程与技术》2016,39(6):1171-1176
Emission of sulfur compounds to the atmosphere is universally recognized as one key target to be reduced. For membrane pervaporation which is considered as a potential purification process of fuels, dual‐layer polyurethane (PU)/polyethersulfone hollow‐fiber membranes were prepared. A novel fabrication technique is proposed using a quadruple spinneret to produce the fiber with such morphology by simultaneous spinning of two polymer solutions in the presence of two corresponding precipitation media. Activated carbon was added into the PU solution to improve the transport properties of the selective layer. Resulting hollow‐fiber membranes showed very good adhesion between the selective layer and its support, in addition to an effective removal of a sulfur compound such as 2‐methyl thiophene from a typical model fuel, an indication of good prospects for both the fabrication technique and for sulfur removal by pervaporation of fuels. 相似文献
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Dr. Nicola d'Avanzo Dr. Maria Chiara Cristiano Prof. Luisa Di Marzio Maria Chiara Bruno Prof. Donatella Paolino Prof. Christian Celia Prof. Massimo Fresta 《ChemMedChem》2022,17(9):e202200067
The use of proper nanocarriers for dermal and transdermal delivery of anti-inflammatory drugs recently gained several attentions in the scientific community because they pass intact and accumulate payloads in the deepest layers of skin tissue. Ascorbyl palmitate-based vesicles (aspasomes) can be considered a promising nanocarrier for dermal and transdermal delivery due to their skin whitening properties and suitable delivery of payloads through the skin. The aim of this study was the synthesis of multidrug Idebenone/naproxen co-loaded aspasomes for the development of an effective anti-inflammatory nanomedicine. Aspasomes had suitable physicochemical properties and were safe in vivo if topically applied on human healthy volunteers. Idebenone/naproxen co-loaded aspasomes demonstrated an increased therapeutic efficacy of payloads compared to the commercially available Naprosyn® gel, with a rapid decrease of chemical-induced erythema on human volunteers. These promising results strongly suggested a potential application of Idebenone/naproxen multidrug aspasomes for the development of an effective skin anti-inflammatory therapy. 相似文献
18.
Phase inversion is a very flexible technique to obtain membranes with a large sort of morphologies. Membrane properties can vary greatly depending on the kind of polymer system used. Bisphenol A polycarbonate (PC) could be used as a phase inversion membrane base polymer, and presents very good properties. Nevertheless, very little information on membrane preparation using PC and the phase inversion process can be found in the literature. In this work flat‐sheet microporous membranes were obtained by the phase inversion process using the immersion precipitation technique. A new polymer system was studied, consisting of polycarbonate, N‐methyl‐2‐pyrrolidone as solvent, water as the nonsolvent, and an additive. The influence of some parameters on membrane morphology, such as polymer solution composition, exposition time before immersion into the precipitation bath, and the kind of additive was investigated. Precipitation was followed using light transmission experiments and membrane morphology was observed through Scanning Electron Microscopy (SEM). The viscosity and cloud points of all polymer solutions were also determined. The results were related to the studied synthesis parameters, using the basic principles of membrane formation by the phase inversion technique, looking forward to establishing criteria to control the morphology of flat‐sheet membranes using polycarbonate as the base polymer. The results showed that both additives were able to increase pore interconnectivity and even suppress macrovoid formation. The decrease in the miscibility region of the polymer system and increase in mass transfer resistance are found to be the determining factors during polymer solution precipitation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3085–3096, 2002 相似文献
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Janicy Arantes Carvalho Cristiano Ceron Jayme Flávia Sayuri Matsuo Antonio Claudio Tedesco 《应用聚合物科学杂志》2024,141(8):e54978
Extensive injuries to bone tissue are still considered a significant clinical challenge; therefore, developing new bone tissue engineering (BTE) strategies is still necessary. This work aims to construct and characterize a chitosan-gelatin/hydroxyapatite-based (CG/H) scaffold to provide well-design support for mesenchymal stem cell (MSC) growth and differentiation to osteoblasts. First, the CG/H scaffolds are construct by freeze-drying. Then, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, x-ray diffraction, water uptake, and degradation profiles evaluate the material's surface. In addition, the CG/H morphological, biochemical, and MSC adhesion processes and growth behavior are also assess, indicating reasonable adhesion rates to the surface, low material cytotoxicity, and excellent alkaline phosphatase activity compared to control on the cellular framework. Based on these results, we obtain a highly biocompatible scaffold and that can support osteoblast differentiation. Finally, the in vivo studies demonstrate the CG/H scaffold with MSC adhere is capable of differentiating into osteoblasts, and the application of this scaffold is able to significantly enhance the closure of the bone lesion. Therefore, the CG/H scaffold has potential clinical application for bone regeneration. 相似文献
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Samia Tássia Andrade Maciel Alexander Andrey Lopes da Silva Yasmin Guimarães Pedro Cristiano Nunes da Silva Leôncio Diógenes Tavares Câmara João Monnerat Araújo Ribeiro de Almeida Emerson Schwingel Ribeiro Gabriel Francisco da Silva Lisiane Santos Freitas Donato Alexandre Gomes Aranda 《化学工程与技术》2020,43(11):2149-2159
The catalytic hydrolysis of soybean oil was used as an alternative for the production of monoglycerides (MG) and diglycerides (DG). The reactions were conducted in a stainless-steel tubular reactor in the temperature range of 240–290 °C, on niobium phosphate (NBP) and niobium oxide (NBO) as catalysts. In the hydrolysis reactions at 270 °C, the maximum selectivities of the products of interest were obtained at 22 % MG and 48 % DG for the reaction with NBP, and 7 % MG and 33 % DG with NBO, for 59 % and 36 % of triglyceride conversion in 10 min, respectively. The proposed kinetic model presented a good fit of the theoretical model with the experimental data, showing that the previous hypotheses considered for the mechanism development are suitable for describing the kinetics of soybean oil hydrolysis. 相似文献