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381.
382.
C Castelli A Mazzocchi F Rini P Tarsini L Rivoltini M Maio G Gallino F Belli G Parmiani 《Canadian Metallurgical Quarterly》1998,28(4):1143-1154
A T cell line recognizing autologous and allogeneic HLA-A3.1 melanomas was obtained from a disease-free melanoma patient (patient 15392). By transfection of a tumor cDNA library and in vitro sensitization experiments, the ALLAVGATK gp100/Mel17-derived peptide was found to be the epitope recognized by this melanoma-specific T cell line. The role of the ALLAVGATK peptide in the systemic immune response to melanoma of this patient was evaluated. When pulsed on the autologous peripheral blood mononuclear cells, the ALLAVGATK peptide generated tumor-specific HLA-A3-restricted T lymphocytes and a single restimulation in vitro was sufficient to raise gp100-specific T lymphocytes, indicating a high frequency of epitope-specific T cells. gp100-specific T cells were also induced from T lymphocytes purified from tumor-invaded lymph nodes (tumor-associated lymphocytes, TAL). TAL-derived effectors displayed lower peptide affinity and lower tumor recognition than effectors elicited from peripheral blood lymphocytes (PBL). To further evaluate its immunogenicity, ALLAVGATK was used to stimulate PBL derived from six additional HLA-A3.1 melanoma patients and seven healthy donors. After 7 weeks of peptide stimulation in vitro the generation of anti-gp100 and tumor-specific T cell lines was achieved in one out of the six patients analyzed. Taken together these data indicate that an in vivo priming leading to a systemic immunity against gp100 in HLA-A3 melanoma patients may occasionally occur and that the immunogenicity of ALLAVGATK peptide in melanoma patients is comparable to that of other HLA-A2-restricted epitopes derived from gp100/Mel 17 protein. 相似文献
383.
Placental malaria is recognized as a common complication of malaria in pregnancy in areas of stable transmission, and is particularly frequent and severe in primigravidae. Many hypotheses, based on a systemic or local failure of the immunological response to malaria, have been proposed to explain the 'preference' of the parasites for replication in the placenta. Some of the hypotheses are briefly reviewed here, with a particular focus on the discovery of an uncommon subpopulation of Plasmodium falciparum which can adhere and massively sequester in the placenta. Histologically, placental malaria is characterized by the presence of parasites and leucocytes within the intervillous spaces, pigment within macrophages, fibrin deposits and trophoblasts, proliferation of cytotrophoblastic cells and thickening of the trophoblastic basement membrane. The exact mechanisms leading to placental changes and determining the observed impairment of materno-foetal exchange are incompletely understood. Parasites are unlikely to be directly responsible for the placental pathology, but leucocytes, through the production of non-chemotactic cytokines, might be associated with the thickening of the trophoblastic basement membrane, and might cause a mechanical blockage of oxygen and nutrient transport across the placenta. There is sound epidemiological evidence that placental malaria determines low birthweight, mainly mediated by intrauterine growth retardation, and increases the risk of death and disease during the first year of life. Antimalarial chemoprophylaxis significantly reduces placental malaria and prevents the development of low birthweight. It is likely that, in areas of high endemicity, the placenta is where the drama of maternal malaria is mostly played. A deeper understanding of the mechanisms involved in this process is of key importance in the design of protective interventions which are effective and acceptable during the gestation period. 相似文献
384.
Donatella Albanese Luciano Cinquanta Gennaro Cuccurullo Marisa Di Matteo 《International Journal of Food Science & Technology》2013,48(6):1327-1333
The effects of drying by microwave and convective heating at 60 and 70 °C on colour change, degradation of β‐carotene and the 2,2‐diphenyl‐1‐picrylhydrazyl radical (DPPH) scavenging activity of apricots were evaluated. Microwave heating reduced significantly the drying time (up to 25%), if compared with convective one, also owing to the higher temperature reached during the last phase of the process, as monitored by infrared thermography. Colour changes of apricot surface, described with lightness and hue angle, in both drying methods followed a first‐order reaction (0.927 ≤ R2 ≤ 0.996). The apricots dried by microwave were less affected by the darkening phenomena. The evolution of β‐carotene in fresh apricots (61.2 ± 5.6 mg kg?1 d.w.) during the drying highlighted a wider decrease (about 50%) when microwave heating was employed for both the temperatures used. Radical scavenging activity increased (P < 0.05) in all dried samples except for hot‐air dried apricots at 60 °C. 相似文献
385.
Shant Kenderian Donatella Cerniglia B. Boro Djordjevic Robert E. Green Jr 《Research in Nondestructive Evaluation》2013,24(4):195-207
Long- and short-range acoustic-signal interaction with surface-breaking cracks and geometric boundaries of the rail-wheel tread area are presented in this article. Ultrasonic signals are generated using a laser-line source of varying length and distance from a crack and are detected with a 1-MHz contact transducer to map the sound field behind the crack in the near, intermediate, and far fields of the insonified region. The factors that affect the behavior of a laser-generated surface acoustic wave propagating along the tread area of a rail wheel are discussed. A signal normalization method is proposed to help in sensing the presence of a crack from the transmitted signal unaffected by the boundary effect of the complicated wheel geometry, diffraction of the acoustic wave around the crack tip, and source-to-crack length ratio and separation distance. 相似文献
386.
Nicoletta Bressan Donatella Pavoni 《Computer Methods in Applied Mechanics and Engineering》1990,80(1-3):443-450
We propose two different approaches to the numerical solution of the initial boundary value problem for the Korteweg-De Vries equation; the former is based on the truncation of the domain, the latter on the reduction of the real axis to a bounded interval by a suitable mapping technique. In both cases we consider spectral Chebyshev collocation methods for the space discretization and finite difference schemes for advancing in time. Both single and multi-domain approaches are discussed. We report numerical experiments showing the stability and convergence properties of the methods 相似文献
387.
Mauro Castelli Ivo Gonçalves Leonardo Trujillo Aleš Popovič 《Information Systems Frontiers》2017,19(5):1123-1132
Nowadays, with more than 50 % of the world’s population living in urban areas, cities are facing important environmental challenges. Among them, air pollution has emerged as one of the most important concerns, taking into account the social costs related to the effect of polluted air. According to a report of the World Health Organization, approximately seven million people die each year from the effects of air pollution. Despite this fact, the same report suggests that cities could greatly improve their air quality through local measures by exploiting modern and efficient solutions for smart infrastructures. Ideally, this approach requires insights of how pollutant levels change over time in specific locations. To tackle this problem, we present an evolutionary system for the prediction of pollutants levels based on a recently proposed variant of genetic programming. This system is designed to predict the amount of ozone level, based on the concentration of other pollutants collected by sensors disposed in critical areas of a city. An analysis of data related to the region of Yuen Long (one of the most polluted areas of China), shows the suitability of the proposed system for addressing the problem at hand. In particular, the system is able to predict the ozone level with greater accuracy with respect to other techniques that are commonly used to tackle similar forecasting problems. 相似文献
388.
Noemi Mancosu Donatella Spano Morteza Orang Sara Sarreshteh Richard L. Snyder 《Water Resources Management》2016,30(2):541-557
A successful water management scheme for irrigated crops requires an integrated approach, which accounts for water, soil, and crop management. SIMETAW# is a user friendly soil water balance model that assesses crop water use, irrigation requirements, and generates hypothetical irrigation schedules for a wide range of crops experiencing full or deficit irrigation. SIMETAW# calculates reference evapotranspiration (ETo), and it computes potential crop evapotranspiration (ETc), and the evapotranspiration of applied water (ETaw), which is the amount of irrigation water needed to match losses from the effective soil root zone due to ETc that are not replaced by precipitation and other sources. Using input information on crop and soil characteristics and the distribution uniformity of infiltrated irrigation applications in full or deficit conditions, the model estimates the mean depth of infiltrated water (IW) into each quarter of the field. The impact of deficit irrigation on the actual crop evapotranspiration (ETa) is computed separately for each of the four quarters of the cropped field. SIMETAW# simulation adjusts ETo estimates for projected future CO2 concentration, and hence the model can assess climate change impacts on future irrigation demand allowing the user to propose adaptation strategies that potentially lead to a more sustainable water use. This paper discusses the SIMETAW# model and evaluates its performance on estimating ETc, ETa, and ETaw for three case studies. 相似文献
389.
This paper presents an innovative approach to maximally disconnect a given network. More specifically, this work introduces the concept of a Critical Disruption Path, a path between a source and a destination vertex whose deletion minimizes the cardinality of the largest remaining connected component. Network interdiction models seek to optimally disrupt network operations. Existing interdiction models disrupt network operations by removing vertices or edges. We introduce the first problem and formulation that optimally fragments a network via interdicting a path. Areas of study in which this work can be applied include transportation and evacuation networks, surveillance and reconnaissance operations, anti-terrorism activities, drug interdiction, and counter human-trafficking operations. In this paper, we first address the complexity associated with the Critical Disruption Path problem, and then provide a Mixed-Integer Linear Programming formulation for finding its optimal solution. Further, we develop a tailored Branch-and-Price algorithm that efficiently solves the Critical Disruption Path problem. We demonstrate the superiority of the developed Branch-and-Price algorithm by comparing the results found via our algorithm with the results found via the monolith formulation. In more than half of the test instances that can be solved by both the monolith and our Branch-and-Price algorithm, we outperform the monolith by two orders of magnitude. 相似文献
390.
Francesco Giuseppe Carollo Vito Ferro Donatella Termini 《Canadian Metallurgical Quarterly》2005,131(12):1050-1061
In this paper, the results of an experimental investigation of the turbulence intensity in gravel bed channels are described. The runs were carried out by measuring, with an acoustic Doppler velocimeter, the turbulence intensity profile along six verticals of a given cross section in a laboratory flume. The analysis of the measured intensity distributions has shown the existence of two different regions, above and below the tops of the roughness elements, in which different intensity profiles occur. Furthermore, the measured profiles have shown a maximum of the turbulence intensity that decreases for increasing values of the roughness height, confirming that the turbulence damping efficiency increases when the roughness elements protrude inside the flow. The applicability of Nezu’s relationship (derived for a hydraulically smooth bed) for the experimental intensity profiles above the roughness elements is positively tested. Finally a new intensity distribution for a rough bed, applicable to the whole water depth, is proposed. In this profile, two coefficients having a known physical meaning (the maximum turbulence intensity and the depth at which this maximum is located) appear. 相似文献