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61.
Gloria Lazzeri Carla L. Busceti Francesca Biagioni Cinzia Fabrizi Gabriele Morucci Filippo S. Giorgi Michela Ferrucci Paola Lenzi Stefano Puglisi-Allegra Francesco Fornai 《International journal of molecular sciences》2021,22(13)
Norepinephrine (NE) neurons and extracellular NE exert some protective effects against a variety of insults, including methamphetamine (Meth)-induced cell damage. The intimate mechanism of protection remains difficult to be analyzed in vivo. In fact, this may occur directly on target neurons or as the indirect consequence of NE-induced alterations in the activity of trans-synaptic loops. Therefore, to elude neuronal networks, which may contribute to these effects in vivo, the present study investigates whether NE still protects when directly applied to Meth-treated PC12 cells. Meth was selected based on its detrimental effects along various specific brain areas. The study shows that NE directly protects in vitro against Meth-induced cell damage. The present study indicates that such an effect fully depends on the activation of plasma membrane β2-adrenergic receptors (ARs). Evidence indicates that β2-ARs activation restores autophagy, which is impaired by Meth administration. This occurs via restoration of the autophagy flux and, as assessed by ultrastructural morphometry, by preventing the dissipation of microtubule-associated protein 1 light chain 3 (LC3) from autophagy vacuoles to the cytosol, which is produced instead during Meth toxicity. These findings may have an impact in a variety of degenerative conditions characterized by NE deficiency along with autophagy impairment. 相似文献
62.
In this letter, we propose and compare some design criteria for the search of good rate-compatible systematic turbo codes (RCPTC) families. The considerations presented by Benedetto et al. to find "best" component encoders for turbo-code construction are extended to find good rate-compatible puncturing patterns leading to codes with promising performances. 相似文献
63.
Summary This paper analyzes Internet diffusion among various organizations, based on daily observation of second- level domain name
registrations under the “.it”ccTLD. In particular, we analyzed domain names registered by organizations in the non-profit
sector.<span style='font-size:12.0pt;mso-ansi-language: HU'>The penetration rate, calculated according to the number of organizations,
was computed for various widely separated geographic levels (regions). A concentration analysis was performed in order to
determine whether the geographical distribution of Internet use in Italy is less concentrated with respect to both the number
of existing institutions and income distribution, suggesting a diffusive effect.<span lang=EN-US style='font-size:12.0pt;
mso-ansi-language:EN-US'>Regression analysis was performed using demographic, social, economic and infrastructure indicators.
Results show that<span style='font-size:12.0pt;mso-ansi-language:HU'>a “social digital divide”exists, both in terms of geographical
distribution (i.e., in macro-areas - Northern, Central, and Southern Italy - and at the regional level) and in terms of the
legal status of the organizations, and that this digital divide will probably decrease in the future. 相似文献
64.
Benedetto S. Garello R. Mondin M. Montorsi G. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1993,39(6):1773-1798
The theory of geometrically uniform trellis codes is applied to the case of multidimensional PSK (phase shift keying) constellations. The symmetry group of an L×MPSK (M-ary PSK) constellation is completely characterized. Conditions for rotational invariance of geometrically uniform partitions of a signal constellation are given. Through suitable algorithms, geometrically uniform partitions of L×MPSK (M=4,8,16 and L=1,2,3,4) constellations are found, which present good characteristics in terms of the set of distances at a given partition level, the maximum obtainable rotational invariance, and the isomorphism of the quotient group associated with the partition. These partitions are used as starting points in a search for good geometrically uniform trellis codes based on binary convolutional codes 相似文献
65.
MHOMS: high-speed ACM modem for satellite applications 总被引:1,自引:0,他引:1
Benedetto S. Garello R. Montorsi G. Berrou C. Douillard C. Giancristofaro D. Ginesi A. Giugno L. Luise M. 《Wireless Communications, IEEE》2005,12(2):66-77
This article presents the novel FPGA-based 1 Gb/s near-Shannon-limit ACM modem developed within the MHOMS program with particular focus on the advanced modem algorithm solutions devised. A number of powerful FEC schemes have been analyzed as possible candidates for the MHOMS modem, and the final selection is justified in terms of the best tradeoff between complexity and performance. State-of-the-art modulation and demodulation algorithms are also presented, including nonlinearity dynamic precompensation techniques and innovative synchronization strategies required by the selected powerful modulation and coding schemes. Overall modem performances are also shown for a variety of spectral efficiencies. 相似文献
66.
Passer Michael W.; Kelley Harold H.; Michela John L. 《Canadian Metallurgical Quarterly》1978,36(9):951
Conducted studies to determine empirically the dimensions underlying attributions made for negative behavior in a close interpersonal relationship (a marriage). 96 university students rated the similarity of 13 causes given either by the enactor of a negative behavior (i.e., the actor) or by the person affected by the behavior (the partner or spouse). A multidimensional scaling analysis of these data yielded 2 dimensions in each condition. The interpretation of these dimensions was guided by data from 68 additional Ss who rated the 13 causes on bipolar scales (e.g., temporary–permanent). Dimension 1 in both conditions was interpreted as "positive vs negative attitude toward spouse." Dimension 2 of the actor condition was interpreted as "intentional vs unintentional" and Dimension 2 of the partner condition as "actor's traits vs circumstances or states." These dimensions are discussed in relation to the a priori causal distinctions made in current attribution writings and previous findings concerning actor–observer biases. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
68.
Cristina Siligardi Monica Montecchi Monia Montorsi Luca Pasquali 《Journal of the American Ceramic Society》2009,92(11):2784-2790
A lead-free frit containing high amount of copper and its glaze conceived for fine porcelain stoneware tiles were investigated. The glazes obtained under industrial firing were studied using X-ray photoelectron spectroscopy, X-ray diffraction, optical and scanning electron microscopy with energy dispersion spectroscopy. The mechanism of the red color formation on the surface was explained. The results indicated that the glaze presents a metallic gloss and iridescent colors on the surface, mainly associated to the formation of CuO crystallites and Cu metallic particles. Moreover, the Cu glaze showed a good chemical durability; this is particularly interesting because commercial Cu frits usually present poor chemical properties. 相似文献
69.
Lorenzo Ball Emanuela Barisione Luca Mastracci Michela Campora Delfina Costa Chiara Robba Denise Battaglini Marco Micali Federico Costantino Giuseppe Cittadini Nicol Patroniti Paolo Pelosi Roberto Fiocca Federica Grillo 《International journal of molecular sciences》2021,22(14)
Lung fibrosis has specific computed tomography (CT) findings and represents a common finding in advanced COVID-19 pneumonia whose reversibility has been poorly investigated. The aim of this study was to quantify the extension of collagen deposition and aeration in postmortem cryobiopsies of critically ill COVID-19 patients and to describe the correlations with qualitative and quantitative analyses of lung CT. Postmortem transbronchial cryobiopsy samples were obtained, formalin fixed, paraffin embedded and stained with Sirius red to quantify collagen deposition, defining fibrotic samples as those with collagen deposition above 10%. Lung CT images were analyzed qualitatively with a radiographic score and quantitatively with computer-based analysis at the lobe level. Thirty samples from 10 patients with COVID-19 pneumonia deceased during invasive mechanical ventilation were included in this study. The median [interquartile range] percent collagen extension was 6.8% (4.6–16.2%). In fibrotic compared to nonfibrotic samples, the qualitative score was higher (260 (250–290) vs. 190 (120–270), p = 0.036) while the gas fraction was lower (0.46 (0.32–0.47) vs. 0.59 (0.37–0.68), p = 0.047). A radiographic score above 230 had 100% sensitivity (95% confidence interval, CI: 66.4% to 100%) and 66.7% specificity (95% CI: 41.0% to 92.3%) to detect fibrotic samples, while a gas fraction below 0.57 had 100% sensitivity (95% CI: 66.4% to 100%) and 57.1% specificity (95% CI: 26.3% to 88.0%). In COVID-19 pneumonia, qualitative and quantitative analyses of lung CT images have high sensitivity but moderate to low specificity to detect histopathological fibrosis. Pseudofibrotic CT findings do not always correspond to increased collagen deposition. 相似文献
70.
Elena Maestri Milica Pavlicevic Michela Montorsi Nelson Marmiroli 《Comprehensive Reviews in Food Science and Food Safety》2019,18(1):3-30
Amino acid (AA) sequences of 807 bioactive peptides from foods of animal origin were examined in order to correlate peptide structure with activity (antihypertensive, antioxidative, immunomodulatory, antimicrobial, hypolipidemic, antithrombotic, and opioid) and stability in vivo. Food sources, such as milk, meat, eggs, and marine products, show different frequencies of bioactive peptides exhibiting specific effects. There is a correlation of peptide structure and effect, depending on type and position of AA. Opioid peptides contain a high percentage of aromatic AA residues, while antimicrobial peptides show an excess of positively charged AAs. AA residue position is significant, with those in the first and penultimate positions having the biggest effects on peptide activity. Peptides that have activity in vivo contain a high percentage (67%) of proline residues, but the positions of proline in the sequence depend on the length of the peptide. We also discuss the influence of processing on activity of these peptides, as well as methods for predicting release from the source protein and activity of peptides. 相似文献