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181.
Eriksson J Roccaforte F Reshanov S Leone S Giannazzo F Lonigro R Fiorenza P Raineri V 《Nanoscale research letters》2011,6(1):120
In this work, the transport properties of metal/3C-SiC interfaces were monitored employing a nanoscale characterization approach in combination with conventional electrical measurements. In particular, using conductive atomic force microscopy allowed demonstrating that the stacking fault is the most pervasive, electrically active extended defect at 3C-SiC(111) surfaces, and it can be electrically passivated by an ultraviolet irradiation treatment. For the Au/3C-SiC Schottky interface, a contact area dependence of the Schottky barrier height (ΦB) was found even after this passivation, indicating that there are still some electrically active defects at the interface. Improved electrical properties were observed in the case of the Pt/3C-SiC system. In this case, annealing at 500°C resulted in a reduction of the leakage current and an increase of the Schottky barrier height (from 0.77 to 1.12 eV). A structural analysis of the reaction zone carried out by transmission electron microscopy [TEM] and X-ray diffraction showed that the improved electrical properties can be attributed to a consumption of the surface layer of SiC due to silicide (Pt2Si) formation. The degradation of Schottky characteristics at higher temperatures (up to 900°C) could be ascribed to the out-diffusion and aggregation of carbon into clusters, observed by TEM analysis. 相似文献
182.
Characterization and effect of year of harvest on the nutritional properties of three varieties of white lupine (Lupinus albus L.) 下载免费PDF全文
183.
Andrea C. Rossetti Maria Serena Paladini Cesar Augusto Brüning Vittoria Spero Maria Grazia Cattaneo Giorgio Racagni Mariusz Papp Marco A. Riva Raffaella Molteni 《International journal of molecular sciences》2022,23(20)
Neuroinflammation has emerged as an important factor in the molecular underpinnings of major depressive disorder (MDD) pathophysiology and in the mechanism of action of antidepressants. Among the inflammatory mediators dysregulated in depressed patients, interleukin (IL)-6 has recently been proposed to play a crucial role. IL-6 activates a signaling pathway comprising the JAK/STAT proteins and characterized by a specific negative feedback loop exerted by the cytoplasmic protein suppressor of cytokine signalling-3 (SOCS3). On these bases, here, we explored the potential involvement of IL-6 signaling in the ability of the antidepressant drug agomelatine to normalize the anhedonic-like phenotype induced in the rat by chronic stress exposure. To this aim, adult male Wistar rats were subjected to the chronic mild stress (CMS) paradigm and chronically treated with vehicle or agomelatine. The behavioral evaluation was assessed by the sucrose consumption test, whereas molecular analyses were performed in the prefrontal cortex. We found that CMS was able to stimulate IL-6 production and signaling, including SOCS3 gene and protein expression, but the SOCS3-mediated feedback-loop inhibition failed to suppress the IL-6 cascade in stressed animals. Conversely, agomelatine treatment normalized the stress-induced decrease in sucrose consumption and restored the negative modulation of the IL-6 signaling via SOCS3 expression and activity. Our results provide additional information about the pleiotropic mechanisms that contribute to agomelatine’s therapeutic effects. 相似文献
184.
While the U.S. Food and Drug Administration and the European Medicines Evaluation Agency have recently approved new drugs to treat spinal muscular atrophy 1 (SMA1) in young patients, they are mostly ineffective in older patients since many motor neurons have already been lost. Therefore, understanding nervous system (NS) physiology in SMA patients is essential. Consequently, studying neural stem cells (NSCs) from SMA patients is of significant interest in searching for new treatment targets that will enable researchers to identify new pharmacological approaches. However, studying NSCs in these patients is challenging since their isolation damages the NS, making it impossible with living patients. Nevertheless, it is possible to study NSCs from animal models or create them by differentiating induced pluripotent stem cells obtained from SMA patient peripheral tissues. On the other hand, therapeutic interventions such as NSCs transplantation could ameliorate SMA condition. This review summarizes current knowledge on the physiological properties of NSCs from animals and human cellular models with an SMA background converging on the molecular and neuronal circuit formation alterations of SMA fetuses and is not focused on the treatment of SMA. By understanding how SMA alters NSC physiology, we can identify new and promising interventions that could help support affected patients. 相似文献
185.
Simone Vespa Pietro Del Biondo Pasquale Simeone Enrico Cavallucci Giulia Catitti Raffaella Auciello Domenico De Bellis Isotta Altomare Laura Pierdomenico Barbara Canonico Ilaria Cicalini Ilaria Angilletta Piero Del Boccio Damiana Pieragostino Francesca Santilli Andrea Urbani Vincenzo De Laurenzi Liborio Stuppia Paola Lanuti 《International journal of molecular sciences》2022,23(23)
Allergic reactions to COVID-19 vaccine components are rare but should be considered. Polyethylene glycol (PEG) is responsible for anaphylaxis in mRNA vaccines. Skin tests have been used in the allergological work-up programs for COVID-19 vaccine evaluation. However, the reproducibility of the skin prick test is time-dependent and the reactivity declines over time. Therefore, we combined the administration of the skin tests with the basophil activation test (BAT) using PEG2000, PEG4000 and DMG-PEG2000, where the BAT was considered positive when the percentage of activated basophils was higher than 6%, 5% and 6.5%, for PEG 4000, PEG2000 and DMG-PEG2000, respectively. To this end, among the subjects that underwent allergy counseling at the Allergy Unit of our Institution during the 2020/2021 vaccination campaign, 13 patients had a suggested medical history of PEG/drug hypersensitivity and were enrolled together with 10 healthy donors. Among the enrolled patients 2 out of 13 tested patients were positive to the skin test. The BAT was negative in terms of the percentages of activated basophils in all analyzed samples, but the stimulation index (SI) was higher than 2.5 in 4 out of 13 patients. These data evidenced that, when the SI is higher than 2.5, even in the absence of positivity to BAT, the BAT to PEG may be a useful tool to be coupled to skin tests to evidence even low-grade reactions. 相似文献
186.
Giovanni Leone Raffaella Barresi 《AEUE-International Journal of Electronics and Communications》2009,63(1):24-30
The problem of the localization and the determination of the extent of a void layer embedded in a masonry structure starting from the knowledge of the scattered field is addressed. The problem is recast as the subsequent localization of single interfaces by using an inverse scattering approach in frequency domain. Each interface is searched by assuming the dielectric properties of the wall known and inverting an appropriate linear model. Experimental validation of the approach is performed by means of scattered field measurements collected at different frequencies in controlled conditions for a tuff masonry illuminated by a bow-tie antenna. 相似文献
187.
Grazia Pastorelli Vittorio M Moretti Paolo Macchioni Domenico P Lo Fiego Piero Santoro Sara Panseri Raffaella Rossi Carlo Corino 《Journal of the science of food and agriculture》2005,85(13):2227-2234
This study evaluated the effects of dietary conjugated linoleic acid (CLA) on fatty acid composition, chemical composition and volatile compounds profile of the longissimus dorsi muscle in Italian heavy pigs. The animals (97 kg) were randomly assigned to three diets varying in supplemental CLA (CON = 0 CLA, T1 = 2.5 g CLA kg−1 feed and T2 = 5.0 g CLA kg−1 feed) till the slaughtering at 172 kg. Samples of longissimus dorsi were analysed for chemical composition (moisture, protein and lipid content), fatty acid composition and volatile compounds. No significant differences were observed for proximate chemical composition. Dietary CLA showed limited effects on fatty acid composition of longissimus dorsi, with higher, but not significantly, amounts of saturated fatty acids in the treated groups than in the control group; both the cis‐9, trans‐11 and the trans‐10, cis‐12 isomers of CLA were increased in longissimus dorsi from pigs fed CLA. T1 and T2 pigs had a greater concentration of C16:0 and of C16:1 (P < 0.01) than CON. CLA diets tended to reduce C20:2 (P = 0.077) and C20:4 (P = 0.065) content in longissimus dorsi muscle. Diets containing higher amount of CLA were responsible for increased levels of volatile compounds in meat, but not at a significant level. Copyright © 2005 Society of Chemical Industry 相似文献
188.
Simulation of Municipal Solid Waste Incinerator Ash/Cement Systems by Means of Factorial Experiments
Alessandra Polettini Raffaella Pomi Gemma Morelli 《Canadian Metallurgical Quarterly》2003,129(11):1051-1060
In the present paper, the behavior of municipal solid waste incinerator ash in cement-based systems was simulated by spiking experiments on portland cement making use of pure compounds, including MgCl2, K2SO4, Zn(NO3)2, and NaNO2, which were selected based on the findings from previous investigation. A 24?1 fractional factorial design was used to arrange the program of experiments. The evolution of physical and mechanical properties as well as acid neutralization capacity with curing time was studied with the aid of statistical analysis. Based on the results from the present work, a model was developed for prediction of unconfined compressive strength and buffering capacity of incinerator ash?portland cement mixtures. The good agreement between predicted and measured values indicated that the behavior of incinerator ash in cementitious systems is largely to be ascribed to the four selected compounds. 相似文献
189.
190.
Lillà Lionetti Maria Pina Mollica Raffaella Sica Immacolata Donizzetti Giorgio Gifuni Angelica Pignalosa Gina Cavaliere Rosalba Putti 《International journal of molecular sciences》2014,15(2):3040-3063
Dietary fat sources may differentially affect the development of inflammation in insulin-sensitive tissues during chronic overfeeding. Considering the anti-inflammatory properties of ω-3 fatty acids, this study aimed to compare the effects of chronic high-fish oil and high-lard diets on obesity-related inflammation by evaluating serum and tissue adipokine levels and histological features in insulin-sensitive tissues (white adipose tissue, skeletal muscle and liver). As expected, a high-lard diet induced systemic and peripheral inflammation and insulin resistance. Conversely, compared with a high-lard diet, a high-fish oil diet resulted in a lower degree of systemic inflammation and insulin resistance that were associated with a lower adipocyte diameter as well as lower immunoreactivity for transforming growth factor β 1 (TGFβ1) in white adipose tissue. A high-fish oil diet also resulted in a lower ectopic lipid depot, inflammation degree and insulin resistance in the skeletal muscle and liver. Moreover, a high-fish oil diet attenuated hepatic stellate cell activation and fibrogenesis in the liver, as indicated by the smooth muscle α-actin (α-SMA) and TGFβ1 levels. The replacement of lard (saturated fatty acids) with fish oil (ω-3 fatty acids) in chronic high-fat feeding attenuated the development of systemic and tissue inflammation. 相似文献