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排序方式: 共有297条查询结果,搜索用时 125 毫秒
81.
Sophie Salasca Bruno Cantone André Grosman Basilio Esposito Fabio Moro Daniele Morocco Rosaria Villari Maurizio Angelone Esther Rincon Carlos Hidalgo Daniel Nagy Gabor Kocsis Paulo Varela Gabor Porempovics Guillaume Perrollaz Kunal Patel Yuri Krivchenkov Michael Walsh 《Fusion Engineering and Design》2013,88(6-8):602-606
Diagnostics in ITER are mandatory to characterize the parameters of plasma and study its interactions with plasma-facing components. Diagnostics components in the vicinity of the plasma are supported by metallic structures called port plugs. At the tokamak mid-plane, these components are installed in port plugs through intermediate structures called drawers. Apart from hosting the diagnostics, the port plugs act as shielding against neutrons and gammas, in order to limit the nuclear loads in crucial components (such as diagnostics and superconducting coils) as well as the dose levels in the controlled zones of the tokamak. The radiation shielding function of the port plugs is ensured through an optimized mixture of heavy metallic materials and water, forming shielding blocks surrounding the diagnostics and called Diagnostic Shield Modules (DSMs). These DSMs constitute the rear part of the drawers (the front part being composed of the Diagnostic First Wall). This paper presents the main results of a study performed in Europe on the integration of a particular diagnostics port plug, the Equatorial Port Plug 1 (EPP1). The paper first provides the results of the EPP1 diagnostics integration analysis. In a second step it focuses on the design of the EPP1 DSMs and summarizes the major results of a thorough set of analyses aiming at studying the DSMs behaviour under different loads, suggesting recommendations to improve their current design. 相似文献
82.
Rosaria Notariale Rosmara Infantino Enza Palazzo Caterina Manna 《International journal of molecular sciences》2021,22(12)
Heavy metals are toxic environmental pollutants associated with severe ecological and human health risks. Among them is mercury (Hg), widespread in air, soil, and water, due to its peculiar geo-biochemical cycle. The clinical consequences of Hg exposure include neurotoxicity and nephrotoxicity. Furthermore, increased risk for cardiovascular diseases is also reported due to a direct effect on cardiovascular tissues, including endothelial cells, recently identified as important targets for the harmful action of heavy metals. In this review, we will discuss the rationale for the potential use of erythrocytes as a surrogate model to study Hg-related toxicity on the cardiovascular system. The toxic effects of Hg on erythrocytes have been amply investigated in the last few years. Among the observed alterations, phosphatidylserine exposure has been proposed as an underlying mechanism responsible for Hg-induced increased proatherogenic and prothrombotic activity of these cells. Furthermore, following Hg-exposure, a decrease in NOS activity has also been reported, with consequent lowering of NO bioavailability, thus impairing endothelial function. An additional mechanism that may induce a decrease in NO availability is the generation of an oxidative microenvironment. Finally, considering that chronic Hg exposure mainly occurs through contaminated foods, the protective effect of dietary components is also discussed. 相似文献
83.
84.
Roma Giuliani Antonio Bevilacqua Maria Rosaria Corbo Carla Severini 《Innovative Food Science and Emerging Technologies》2010,11(2):328-334
The effects of a short-time microwave (MW) treatments on the survival of Alicyclobacillus acidoterrestris spores (105 spores/g) inoculated in a cream of asparagus, along with the oxidation of the fat component (olive oil), were investigated.The samples were MW-treated at 60–100% of power (2450 MHz) for 3–7 min; power and processing time changed according to a Central Composite Design at two variables/five levels. The combinations resulting in a 2-fold reduction in the number of alicyclobacilli spores (100% of power–5 min; 80%–6 min; 80%–7 min) were stored at different temperatures and times (25 °C/27 days, 37 °C/18 days and 50 °C/9 days), to determine the decay of the qualitative characteristics of the lipid fraction. Peroxide value, K232, K270 and Rancimat test (induction time) were chosen as indexes of primary and secondary oxidation. MW-effect on the spores depended upon both the power and the treatment time; moreover the interaction [power] × [time] was the most significant variable. As regards the effect of MW on the lipid fraction, the results suggested that MW affected slightly induction time, peroxide values and spectrophotometric determinations, especially at low powers.Industrial relevanceSince the middle of 1990s, MW-processing has been regarded as a convenient approach for the stabilization of vegetable preserves. In Southern Italy, olive oil is an essential ingredient for this kind of food; however, it is well known that a strong thermal processing as well as not-correct storage could affect it significantly and increase the art of oxidation.This research provides some useful information on the effects of MW for a new product, an asparagus cream, focusing on the influence of this approach on olive oil oxidation, thus suggesting that MW could be a convenient preservation technique. 相似文献
85.
Shelf life of minimally processed vegetables is often calculated by using the kinetic parameters of Gompertz equation as modified by Zwietering et al. [Zwietering, M.H., Jongenburger, F.M., Roumbouts, M., van't Riet, K., 1990. Modelling of the bacterial growth curve. Applied and Environmental Microbiology 56, 1875-1881.] taking 5x10(7) CFU/g as the maximum acceptable contamination value consistent with acceptable quality of these products. As this method does not allow estimation of the standard errors of the shelf life, in this paper the modified Gompertz equation was re-parameterized to directly include the shelf life as a fitting parameter among the Gompertz parameters. Being the shelf life a fitting parameter is possible to determine its confidence interval by fitting the proposed equation to the experimental data. The goodness-of-fit of this new equation was tested by using mesophilic bacteria cell loads from different minimally processed vegetables (packaged fresh-cut lettuce, fennel and shredded carrots) that differed for some process operations or for package atmosphere. The new equation was able to describe the data well and to estimate the shelf life. The results obtained emphasize the importance of using the standard errors for the shelf life value to show significant differences among the samples. 相似文献
86.
Development of antiviral fusion inhibitors: short modified peptides derived from the transmembrane glycoprotein of feline immunodeficiency virus 总被引:2,自引:0,他引:2
D'Ursi AM Giannecchini S Esposito C Alcaro MC Sichi O Armenante MR Carotenuto A Papini AM Bendinelli M Rovero P 《Chembiochem : a European journal of chemical biology》2006,7(5):774-779
Feline immunodeficiency virus (FIV) is a naturally occurring pathogen that causes an AIDS-like syndrome in domestic cats and is a valuable model system by which criteria for antiviral vaccines and drugs development can be tested. The cell-entry step of the lentivirus life cycle is regarded as a promising target for the development of new generation inhibitors. We have previously described potent in vitro anti-FIV activity associated with a synthetic octapeptide, termed C8 (Ac-Trp-Glu-Asp-Trp-Val-Gly-Trp-Ile-NH2), containing the Trp-rich motif of FIV transmembrane glycoprotein, which shares a common structural framework with the corresponding molecule of HIV and appears to play a similar role in cell entry. In this report, in an attempt to develop simpler potential fusion inhibitors to be tested in vivo, we describe further studies focused on synthetic peptide analogues of C8. Since C8 inhibitory activity is dependent upon the Trp motif, we systematically replaced these residues with bulky and/or aromatic natural and unnatural amino acids, in order to develop a rational structure-activity relationship. Furthermore, the amino acids located between the Trp residues, which are not crucial for inhibitory activity, were replaced by simple alkyl spacers of appropriate length. Design, NMR structural analysis, in vitro anti-FIV activity in lymphoid cell cultures, and serum stability of these new analogues are reported. The final results indicate that a simpler hexapeptide (Ac-Nal2-Ape-Nal2-Ape-Nal2-Ile-NH2; Nal2 = 3-naphthalen-2-yl-L-alanine, Ape = 5-aminopentanoic acid), almost entirely made up of unnatural amino acid residues, has markedly increased enzymatic stability, while maintaining strong antiviral potency in vitro. 相似文献
87.
Maria Cefola Maria L Amodio Rosaria Cornacchia Raffaella Rinaldi Sebastiano Vanadia Giancarlo Colelli 《Journal of the science of food and agriculture》2010,90(5):789-797
BACKGROUND: Many leafy brassicas are widely used for ready‐to‐use salads. Broccoli raab (Brassica rapa L.), also called turnip top, or rapini, is extensively cultivated in southern Italy. The edible portion is made up of the green, immature inflorescences and the stem with its most tender leaves. Recently, interest in this crop has increased among European consumers; moreover, a substantial increase in consumption could come from the ready‐to‐use product. RESULTS: The effects of four different atmosphere compositions (air, 3% O2 in nitrogen, 3% O2 + 10% CO2 in air, and 10% CO2 in air) on quality attributes of ready‐to‐use broccoli raab were studied. Controlled atmosphere affected appearance, composition, respiration rate, weight loss, and presence of off‐odours. Storage of broccoli raab florets under low oxygen conditions delayed post‐cutting deterioration during storage at 5 °C and preserved appearance and typical odour, up to 17 days. Moreover, respiration rate as well as loss of green colour, chlorophyll and vitamin C were also slowed down in this condition. Finally, in this study no effect of controlled atmosphere storage was found on total phenols content and antioxidant activity. CONCLUSION: Results showed that cold storage in 3% O2 can be beneficial in order to maintain quality of ready‐to‐use, broccoli raab for up to 17 days. Copyright © 2010 Society of Chemical Industry 相似文献
88.
Rosanna Tortelli Davide Seripa Chiara Zecca Maria Teresa DellAbate Paola Bisceglia Maria Rosaria Barulli Roberto De Blasi Giancarlo Logroscino 《International journal of molecular sciences》2021,22(12)
Mutations in the PSEN1 gene are the most common cause of autosomal dominant Alzheimer’s disease, and are characterized by a high phenotype variability. This study describes a five-generation family, with a prevalent late-onset of the disease and a high frequency of depression, in which a new missense mutation (c.789T > G, p.Cys263Trp) in exon 8 of the PSEN1 gene was found. Only the proband presented an early onset at the age of 45 with attention deficit, followed by spatial disorientation, psychiatric symptoms and parkinsonian signs. The other two cases had a late onset of the disease and a typical presentation with memory loss. Both were characterized by a high level of anxiety and depression. The disease course was different with signs of Lewy body dementia for the proband’s mother, and pyramidal involvement and a shorter disease duration for the proband’s maternal aunt. The other eight cases with late-onset dementia and three cases with a long history of depression have been reported in the family pedigree, underlying the high phenotype variability of PSEN1 mutations. 相似文献
89.
Beatriz Martín‐García Davide Spirito Sebastiano Bellani Mirko Prato Valentino Romano Anatolii Polovitsyn Rosaria Brescia Reinier Oropesa‐Nuez Leyla Najafi Alberto Ansaldo Giovanna D'Angelo Vittorio Pellegrini Roman Krahne Iwan Moreels Francesco Bonaccorso 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(52)
Among the large family of transition metal dichalcogenides, recently ReS2 has stood out due to its nearly layer‐independent optoelectronic and physicochemical properties related to its 1T distorted octahedral structure. This structure leads to strong in‐plane anisotropy, and the presence of active sites at its surface makes ReS2 interesting for gas sensing and catalysts applications. However, current fabrication methods use chemical or physical vapor deposition (CVD or PVD) processes that are costly, time‐consuming and complex, therefore limiting its large‐scale production and exploitation. To address this issue, a colloidal synthesis approach is developed, which allows the production of ReS2 at temperatures below 360 °C and with reaction times shorter than 2h. By combining the solution‐based synthesis with surface functionalization strategies, the feasibility of colloidal ReS2 nanosheet films for sensing different gases is demonstrated with highly competitive performance in comparison with devices built with CVD‐grown ReS2 and MoS2. In addition, the integration of the ReS2 nanosheet films in assemblies together with carbon nanotubes allows to fabricate electrodes for electrocatalysis for H2 production in both acid and alkaline conditions. Results from proof‐of‐principle devices show an electrocatalytic overpotential competitive with devices based on ReS2 produced by CVD, and even with MoS2, WS2, and MoSe2 electrocatalysts. 相似文献
90.
Dr. Francesca Mancuso Prof. Laura De Luca Federica Bucolo Milan Vrabel Dr. Andrea Angeli Dr. Clemente Capasso Prof. Claudiu T. Supuran Rosaria Gitto 《ChemMedChem》2021,16(24):3787-3794
A current issue of antimicrobial therapy is the resistance to treatment with worldwide consequences. Thus, the identification of innovative targets is an intriguing challenge in the drug and development process aimed at newer antimicrobial agents. The state-of-art of anticholera therapy might comprise the reduction of the expression of cholera toxin, which could be reached through the inhibition of carbonic anhydrases expressed in Vibrio cholerae (VchCAα, VchCAβ, and VchCAγ). Therefore, we focused our interest on the exploitation of sulfonamides as VchCA inhibitors. We planned to design and synthesize new benzenesulfonamides based on our knowledge of the VchCA catalytic site. The synthesized compounds were tested thus collecting useful SAR information. From our investigation, we identified new potent VchCA inhibitors, some of them displayed high affinity toward VchCAγ class, for which few inhibitors are currently reported in literature. The best interesting VchCAγ inhibitor (S)-N-(1-oxo-1-((4-sulfamoylbenzyl)amino)propan-2-yl)furan-2-carboxamide ( 40 ) resulted more active and selective inhibitor when compared with acetazolamide (AAZ) as well as previously reported VchCA inhibitors. 相似文献