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51.
M Vergine F Boccaccini M Monti D Antonucci GP Bianchini V Pasta FM Di Matteo M Monti M Mele 《Canadian Metallurgical Quarterly》1997,18(10):752-756
An 8-year-old girl presented with coexistence of ganglioglioma and cortical dysplasia manifesting as intractable epilepsy. Preoperative computed tomography demonstrated a small calcified lesion in the left frontal lobe which was not diagnosed as ganglioglioma. Magnetic resonance imaging also failed to demonstrate positive evidence of ganglioglioma or cortical dysplasia. A calcified tumor and the surrounding epileptogenic areas were resected under electrocorticography (ECoG) guidance. Histological examination revealed coexistence of ganglioglioma and cortical dysplasia. The patient became seizure-free after surgery. Resection of the ganglioglioma together with the adjacent epileptogenic area under intraoperative ECoG guidance is important to achieve a successful surgical result in patients with ganglioglioma. 相似文献
52.
53.
A. S. Aric V. Antonucci N. GiordanoA. K. Shukla M. K. Ravikumar A. Roy S. R. Barman D. D. Sarma 《Journal of power sources》1994,50(3):295-309
A study is made of the electrooxidation of methanol in sulfuric acid on carbon-supported electrodes containing platinum-tin bimetal catalysts that are prepared by an in situ potentiometric-characterization route. The catalysts are investigated by employing chemical analyses, X-ray diffraction (XRD), X-ray absorption-near-edge spectroscopy (XANES) and X-ray photoelectron spectroscopy (XPS) data in conjunction with electrochemical measurements. From the electrochemical data, it is inferred that while an electrode with (3:1) Pt-Sn/C catalyst involves a two-electron rate-limiting step akin to platinum-on-carbon electrodes, it is shifted to a one-electron mechanism on electrodes with (3:2)Pt-Sn/C, (3:3)Pt-Sn/C, and (3:4)Pt-Sn/C catalysts. The study suggests that the tin content in the platinum-tin bimetal catalyst produces: (i) a charge transfer from tin to platinum; (ii) an increase in the coverage of adsorbed methanolic residues with increase in the tin content, as indicated by the shift in rest potential of the electrodes towards the reversible value for oxidation of methanol (0.043 V versus SHE), and (iii) a decrease in the overall content of higher valent platinum sites in the catalyst. 相似文献
54.
Mauro De Marchis Chiara M. Fontanazza Gabriele Freni Vincenza Notaro Valeria Puleo 《Water Resources Management》2016,30(6):2005-2019
Several studies have been carried out in recent decades to establish a relationship between total head and leaks. In literature, the leakage governing equations have been analysed in light of pipe materials, water head, leak dimension or shape. Most of these contributions questioned the classical Torricelli equation, demonstrating through experimental evidence that the classical orifice law can give unsatisfactory results. Nevertheless, starting from the Torricelli equation, other exponential or linear governing equations have been proposed as mathematical models able to reproduce the leakages in water distribution systems (WDSs). To investigate the validity of the proposed governing equations, an experimental campaign was carried out by means of a water distribution network composed of approximately 500 m of polyethylene pipes. The experiments were designed to investigate the effects of leak area and pipe rigidity on discharge. Furthermore, the effect of leak size enlargement with water head was analysed. Finally, the proposed research contributes to the population of a database for estimating the coefficients of head-discharge relationships. 相似文献
55.
V. Baglio A. Stassi A. Di Blasi C. D’Urso V. Antonucci A.S. Aricò 《Electrochimica acta》2007,53(3):1360-1364
A low temperature preparation procedure, based on a combination of colloidal and incipient wetness methods, was developed to modify the Pt catalyst with transition metals (Fe, Cu and Co). A moderate degree of alloying was obtained with Pt-Fe/C and Pt-Co/C cathode catalysts by using the new low temperature preparation route; whereas, a high degree of alloying was obtained for Pt-Cu/C by using the same procedure. Despite of the high metal concentration (60 wt%) on carbon, all catalysts showed small primary metal particle size and a low degree of agglomeration. These catalysts were investigated as cathodes in direct methanol fuel cells (DMFCs) operating at low temperatures (60 °C). It appeared that Pt-Fe/C catalysts were superior than Pt/C, Pt-Co/C and Pt-Cu/C catalysts both in terms of catalytic activity and tolerance to methanol. Adsorbed methanolic residues stripping analysis indicated a better methanol tolerance and an enhanced activity towards oxygen reduction in the case of the Pt-Fe system. An improvement of the DMFC single cell performance was also observed in the presence of Pt-Fe catalysts. 相似文献
56.
The fire behavior and the smoke emission of an unsaturated polyester resin modified by the addition of three phosphorus‐based fire‐retardant materials (ammonium polyphosphate (APP), silane‐coated APP, and melamine pyrophosphate) at two concentration levels (20% w/w, 35% w/w) have been investigated. Scanning electron microscopy, Fourier transform infrared spectroscopy and optical microscopy analysis have been performed to verify the dispersion and the action mechanism of additives within the resin. Results from cone calorimetric tests demonstrated that the incorporation of the fire retardants at 35% w/w has a strong effect on flammability and smoke suppressant properties with respect to both the neat resin and the loaded systems at 20% (w/w). In particular, the smoke formation and smoke parameters are reduced by 50% and 80%, respectively, leading to the conclusion that APP can be used single‐handedly without combination with specific smoke suppressors. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
57.
Marisa Ziino Concetta Condurso Vincenza Romeo Gianluca Tripodi Antonella Verzera 《Journal of the science of food and agriculture》2009,89(5):774-780
BACKGROUND: Because of the great variability in size, shape, colour, pungency and aroma of Calabrian Capsicum annuum(hot pepper), this study was carried out to furnish producers with information on volatile compounds and capsaicinoid content useful for the genetic improvement of this species. Fully ripened fresh peppers of the most widely cultivated varieties were studied. Capsaicinoid content was determined by reverse phase high‐performance liquid chromatography/diode array detection (RP‐HPLC/DAD). Volatile compounds were determined by headspace solid phase microextraction/gas chromatography/mass spectrometry (HS‐SPME/GC/MS). RESULTS: Sixty‐four volatile compounds were identified, the main classes being alcohols, aldehydes, terpenes and aliphatic branched‐chain hydrocarbons. The ‘Naso di cane’ (C. annuumvar. abbreviatum) variety contained the lowest amount of volatiles, especially alcohols and aldehydes, while the highest levels of capsaicin and dihydrocapsaicin were found in ‘Vulcan’ and ‘Corno di capra’ varieties. CONCLUSION: From statistical evaluation of the data obtained, each variety showed a typical composition of capsaicinoids and volatiles determining the taste and odour of the hot peppers. These results should be useful in the context of research aimed at selecting varieties with the best sensory characteristics. Copyright © 2009 Society of Chemical Industry 相似文献
58.
Ania Canseco-Rodriguez Valeria Masola Vincenza Aliperti Maria Meseguer-Beltran Aldo Donizetti Ana María Sanchez-Perez 《International journal of molecular sciences》2022,23(21)
Alzheimer’s Disease (AD) has currently no effective treatment; however, preventive measures have the potential to reduce AD risk. Thus, accurate and early prediction of risk is an important strategy to alleviate the AD burden. Neuroinflammation is a major factor prompting the onset of the disease. Inflammation exerts its toxic effect via multiple mechanisms. Amongst others, it is affecting gene expression via modulation of non-coding RNAs (ncRNAs), such as miRNAs. Recent evidence supports that inflammation can also affect long non-coding RNA (lncRNA) expression. While the association between miRNAs and inflammation in AD has been studied, the role of lncRNAs in neurodegenerative diseases has been less explored. In this review, we focus on lncRNAs and inflammation in the context of AD. Furthermore, since plasma-isolated extracellular vesicles (EVs) are increasingly recognized as an effective monitoring strategy for brain pathologies, we have focused on the studies reporting dysregulated lncRNAs in EVs isolated from AD patients and controls. The revised literature shows a positive association between pro-inflammatory lncRNAs and AD. However, the reports evaluating lncRNA alterations in EVs isolated from the plasma of patients and controls, although still limited, confirm the value of specific lncRNAs associated with AD as reliable biomarkers. This is an emerging field that will open new avenues to improve risk prediction and patient stratification, and may lead to the discovery of potential novel therapeutic targets for AD. 相似文献
59.
Tommaso Piccoli Valeria Blandino Laura Maniscalco Domenica Matranga Fabiola Graziano Fabrizio Guajana Luisa Agnello Bruna Lo Sasso Caterina Maria Gambino Rosaria Vincenza Giglio Vincenzo La Bella Marcello Ciaccio Tiziana Colletti 《International journal of molecular sciences》2022,23(18)
Recently, the synaptic proteins neurogranin (Ng) and α-synuclein (α-Syn) have attracted scientific interest as potential biomarkers for synaptic dysfunction in neurodegenerative diseases. In this study, we measured the CSF Ng and α-Syn concentrations in patients affected by AD (n = 69), non-AD neurodegenerative disorders (n-AD = 50) and non-degenerative disorders (n-ND, n = 98). The concentrations of CSF Ng and α-Syn were significantly higher in AD than in n-AD and n-ND. Moreover, the Aβ42/Ng and Aβ42/α-Syn ratios showed statistically significant differences between groups and discriminated AD patients from n-AD patients, better than Ng or α-Syn alone. Regression analyses showed an association of higher Ng concentrations with MMSE < 24, pathological Aβ 42/40 ratios, pTau, tTau and the ApoEε4 genotype. Aβ 42/Ng was associated with MMSE < 24, an AD-related FDG-PET pattern, the ApoEε4 genotype, pathological Aβ 42 levels and Aβ 42/40 ratios, pTau, and tTau. Moreover, APO-Eε4 carriers showed higher Ng concentrations than non-carriers. Our results support the idea that the Aβ 42/Ng ratio is a reliable index of synaptic dysfunction/degeneration able to discriminate AD from other neurological conditions. 相似文献
60.
A. S. Aric A. Di Blasi G. Brunaccini F. Sergi G. Dispenza L. Andaloro M. Ferraro V. Antonucci P. Asher S. Buche D. Fongalland G. A. Hards J. D. B. Sharman A. Bayer G. Heinz N. Zandon R. Zuber M. Gebert M. Corasaniti A. Ghielmi D. J. Jones 《Fuel Cells》2010,10(6):1013-1023
Polymer electrolyte fuel cell stacks assembled with Johnson Matthey Fuel Cells and SolviCore MEAs based on the Aquivion™ E79‐03S short‐side chain (SSC), chemically stabilised perfluorosulphonic acid membrane developed by Solvay Solexis were investigated at CNR‐ITAE in the EU Sixth Framework ‘Autobrane' project. Electrochemical experiments in fuel cell short stacks were performed under practical automotive operating conditions at pressures of 1–1.5 bar abs. over a wide temperature range, up to 130 °C, with varying levels of humidity (down to 18% R. H.). The stacks using large area (360 cm2) MEAs showed elevated performance in the temperature range from ambient to 100 °C (cell power density in the range of 600–700 mWcm–2) with a moderate decrease above 100 °C. The performances and electrical efficiencies achieved at 110 °C (cell power density of about 400 mWcm–2 at an average cell voltage of about 0.5–0.6 V) are promising for automotive applications. Duty‐cycle and steady‐state galvanostatic experiments showed excellent stack stability for operation at high temperature. A performance comparison of AquivionTM and NafionTM‐based MEAs under practical operating conditions showed a significantly better capability for the Solvay Solexis membrane to sustain high temperature operation. 相似文献