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81.
Roberta Bastos Vasques Marjory Moreira Levy Matheus Souza Rodrigues Francisco Wagner de Queiroz Almeida Neto Leonardo Paes da Silva Gustavo Leitão Vaz Álvaro Augusto Oliveira Magalhães Pedro de Lima-Neto Walney Silva Araújo 《工业材料与腐蚀》2021,72(8):1417-1432
Phosphate ester was investigated as a corrosion inhibitor for AISI 1018 carbon steel in carbon dioxide-saturated chloride solutions at different temperatures and pressures. The corrosion tests were realized by electrochemical techniques, weight loss measurements, bubble tests, and a high-pressure/high-temperature autoclave system. The corrosion tests demonstrated that the investigated molecule is an excellent corrosion inhibitor. The inhibiting effect is even bigger at high pressure and temperature than at atmospheric pressure and room temperature. The thermodynamic parameters were calculated and determined to obey the Langmuir isotherm. Polarization studies revealed that the evaluated inhibitor is a mixed type. 相似文献
82.
In the present study, artificial neural network(ANN) approach was used to predict the stress–strain curve of near beta titanium alloy as a function of volume fractions of a and b. This approach is to develop the best possible combination or neural network(NN) to predict the stress–strain curve. In order to achieve this, three different NN architectures(feed-forward back-propagation network,cascade-forward back-propagation network, and layer recurrent network), three different transfer functions(purelin, Log-Sigmoid, and Tan-Sigmoid), number of hidden layers(1 and 2), number of neurons in the hidden layer(s),and different training algorithms were employed. ANN training modules, the load in terms of strain, and volume fraction of a are the inputs and the stress as an output.ANN system was trained using the prepared training set(a,16 % a, 40 % a, and b stress–strain curves). After training process, test data were used to check system accuracy. It is observed that feed-forward back-propagation network is the fastest, and Log-Sigmoid transfer function is giving the best results. Finally, layer recurrent NN with a single hidden layer consists of 11 neurons, and Log-Sigmoid transfer function using trainlm as training algorithm is giving good result, and average relative error is1.27 ± 1.45 %. In two hidden layers, layer recurrent NN consists of 7 neurons in each hidden layer with trainrp as the training algorithm having the transfer function of LogSigmoid which gives better results. As a result, the NN is founded successful for the prediction of stress–strain curve of near b titanium alloy. 相似文献
83.
Alessia Vignoli Emanuela Risi Amelia McCartney Ilenia Migliaccio Erica Moretti Luca Malorni Claudio Luchinat Laura Biganzoli Leonardo Tenori 《International journal of molecular sciences》2021,22(9)
Precision oncology is an emerging approach in cancer care. It aims at selecting the optimal therapy for the right patient by considering each patient’s unique disease and individual health status. In the last years, it has become evident that breast cancer is an extremely heterogeneous disease, and therefore, patients need to be appropriately stratified to maximize survival and quality of life. Gene-expression tools have already positively assisted clinical decision making by estimating the risk of recurrence and the potential benefit from adjuvant chemotherapy. However, these approaches need refinement to further reduce the proportion of patients potentially exposed to unnecessary chemotherapy. Nuclear magnetic resonance (NMR) metabolomics has demonstrated to be an optimal approach for cancer research and has provided significant results in BC, in particular for prognostic and stratification purposes. In this review, we give an update on the status of NMR-based metabolomic studies for the biochemical characterization and stratification of breast cancer patients using different biospecimens (breast tissue, blood serum/plasma, and urine). 相似文献
84.
Fabio Forghieri Giovanni Riva Ivana Lagreca Patrizia Barozzi Francesca Bettelli Ambra Paolini Vincenzo Nasillo Beatrice Lusenti Valeria Pioli Davide Giusti Andrea Gilioli Corrado Colasante Laura Galassi Hillary Catellani Francesca Donatelli Annalisa Talami Rossana Maffei Silvia Martinelli Leonardo Potenza Roberto Marasca Enrico Tagliafico Rossella Manfredini Tommaso Trenti Patrizia Comoli Mario Luppi 《International journal of molecular sciences》2021,22(17)
The C-terminal aminoacidic sequence from NPM1-mutated protein, absent in normal human tissues, may serve as a leukemia-specific antigen and can be considered an ideal target for NPM1-mutated acute myeloid leukemia (AML) immunotherapy. Different in silico instruments and in vitro/ex vivo immunological platforms have identified the most immunogenic epitopes from NPM1-mutated protein. Spontaneous development of endogenous NPM1-mutated-specific cytotoxic T cells has been observed in patients, potentially contributing to remission maintenance and prolonged survival. Genetically engineered T cells, namely CAR-T or TCR-transduced T cells, directed against NPM1-mutated peptides bound to HLA could prospectively represent a promising therapeutic approach. Although either adoptive or vaccine-based immunotherapies are unlikely to be highly effective in patients with full-blown leukemia, these strategies, potentially in combination with immune-checkpoint inhibitors, could be promising in maintaining remission or preemptively eradicating persistent measurable residual disease, mainly in patients ineligible for allogeneic hematopoietic stem cell transplant (HSCT). Alternatively, neoantigen-specific donor lymphocyte infusion derived from healthy donors and targeting NPM1-mutated protein to selectively elicit graft-versus-leukemia effect may represent an attractive option in subjects experiencing post-HSCT relapse. Future studies are warranted to further investigate dynamics of NPM1-mutated-specific immunity and explore whether novel individualized immunotherapies may have potential clinical utility in NPM1-mutated AML patients. 相似文献
85.
Ronaldo C. Gurgel‐Loureno Leonardo M. Pinto Luis A. V. Bezerra Jorge I. Snchez‐Botero 《河流研究与利用》2020,36(7):1353-1359
Several fish species from Central America and other regions have been introduced into Brazil. In this study, we evaluated the bioecological aspects of a non‐native cichlid of the genus Amatitlania (convict cichlid) and its possible establishment in high‐altitude forest enclaves of semi‐arid Northeastern Brazil. Specimens of Amatitlania nigrofasciata (Günther, 1867) were captured in a local stream displaying abiotic conditions like those of its natural range of distribution. The individuals collected were predominantly adult, insectivorous and displayed normal length–weight relationships, although we observed some phenotypical plasticity (variation in body depth, and a morphologically abnormal dorsal fin in three cases). Our results indicate that A. nigrofasciata has successfully colonized an Atlantic forest enclave in the Brazilian semi‐arid region, making it necessary to adopt measures to prevent the species from spreading to other water bodies in the surroundings. 相似文献
86.
87.
Karolien Verhaegen Leonardo Meeus Ronnie Belmans 《Renewable & Sustainable Energy Reviews》2009,13(1):208-215
In Europe, a common framework for renewable energy sources (RES) is aspired. Tradable green certificates (TGCs) are a market-based cost-efficient means to stimulate electricity production from RES. Since TGCs are the most widespread support scheme in Europe together with feed-in tariffs, chances are that a common European framework could well be based on TGCs. However, while integrating currently existing different national TGC systems, any remaining differences should be carefully considered. Just how difficult the creation of an international TGC market would be is illustrated in this paper by the case of Belgium, where no less than 4 different TGC systems exist nowadays. The example of Belgium illustrates that harmonizing different TGC systems is easier said than done and represents a serious challenge. This clearly illustrates that a single European support scheme for RES, however desirable, is still far in the future. 相似文献
88.
Heloiza Vieira Rodrigues Pereira Karina Peixoto Saraiva Lucia Maria Jaeger Carvalho Leonardo Rodrigues Andrade Cristiana Pedrosa Anna Paola Trindade Rocha Pierucci 《Food research international (Ottawa, Ont.)》2009,42(1):115-121
This study evaluated the use of pea (Pisum sativum) and cowpea (Vigna unguiculata) protein isolates (PPI and CPI) in the microencapsulation of ascorbic acid (AA), by spray drying. PPI and CPI were used pure or mixed with maltodextrin (M) as wall materials of AA. The process yield was improved from 66% to 86% by the addition of M (CPI/M and PPI/M); also, AA particles yield was 79%. The AA retention from the drying process was higher in PPI/M (69%) than in CPI/M (66%), and this was attributed to PPI proteolysis profile, demonstrated by the SDS–PAGE electrophoresis. Scanning electron microscopy revealed that AA particles were similarly spherical and shriveled. Mean particle sizes of PPI/M/AA and CPI/M/AA were 7 and 8 μm, respectively. This study showed the exploration of protein isolates from legumes in the development of a microparticulate system containing AA with great potential for use in human health. 相似文献
89.
Occurrence patterns of alien freshwater turtles in a large urban pond ‘Archipelago’ (Rome,Italy): Suggesting hypotheses on root causes 下载免费PDF全文
Maria Paola Di Santo Leonardo Vignoli Giuseppe M. Carpaneto Corrado Battisti 《Lakes & Reservoirs: Research and Management》2017,22(1):56-64
The patterns of the occurrence and distribution of alien freshwater turtle species in an urban pond archipelago (Rome, Italy) were analysed, with the aim of exploring the role of a set of factors (type of ponds, landscape context, size area, distance from the nearest road) with a generalized linear model approach. A total of 311 ponds subdivided in three types (fountains, small basins, lakes) embedded in different landscape contexts (public parks, private parks, urban areas) at differing distances from the nearest road were sampled. Six non‐native freshwater turtle species in 31 sites were recorded (9.97%). Lakes exhibited the highest occurrence rates of alien freshwater turtles, compared to small basins and fountains. Freshwater turtle species in urbanized areas were only observed in parks (both public and private). In both the public and private parks, the lakes exhibited the highest percentage of occupied sites, with fountains being the lowest. A direct and significant relationship was observed between pond size and species richness. The distance from the nearest road did not appear to affect species richness. A first interpretation of the data from this study facilitated the postulation of two a posteriori hypotheses that should be tested, as follows: (i) the causal process of turtle release is random, and the rate of extinction (and recapture) is higher in smaller ponds, thus producing the observed pattern; and (ii) the turtle release is not random, and people actively select the ponds they consider more suitable for their pet animals. In this study, it appears the lakes were perceived by those who abandon their pets as the most ecologically suitable habitats among other pond types to accommodate the different species of turtles. Knowledge of people's attitudes in regard to releasing pet animals also might assist managers of public green spaces to develop strategies aimed to preserve local biodiversity, and to educate the public about the conservation issue represented by the alien species. 相似文献
90.
Leonardo Dallegrave Afonso Viviana Cocco Mariani Leandro dos Santos Coelho 《Expert systems with applications》2013,40(9):3794-3802
System reliability analysis and optimization are important to efficiently utilize available resources and to develop an optimal system design architecture. System reliability optimization has been solved by using optimization techniques including meta-heuristics. Meanwhile, the development of meta-heuristics has been an active research field of the reliability optimization wherein the redundancy, the component reliability, or both are to be determined. In recent years, a broad class of stochastic meta-heuristics, such as simulated annealing, genetic algorithm, tabu search, ant colony, and particle swarm optimization paradigms, has been developed for reliability-redundancy optimization of systems. Recently, a new kind of evolutionary algorithm called Imperialist Competitive Algorithm (ICA) was proposed. The ICA is based on imperialistic competition where the populations are represented by countries, which are classified as imperialists or colonies. However, the trade-off between the exploration (i.e. the global search) and the exploitation (i.e. the local search) of the search space is critical to the success of the classical ICA approach. An improvement in the ICA by implementing an attraction and repulsion concept during the search for better solutions, the AR-ICA approach, is proposed in this paper. Simulations results demonstrates the AR-ICA is an efficient optimization technique, since it obtained promising solutions for the reliability redundancy allocation problem when compared with the previously best-known results of four different benchmarks for the reliability-redundancy allocation problem presented in the literature. 相似文献