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991.
Marco Roccetti Vittorio Ghini Giovanni Pau Paola Salomoni Maria Elena Bonfigli 《Multimedia Tools and Applications》2001,14(1):23-53
We describe the design and the experimental evaluation of a playout delay control mechanism we have developed in order to support unicast, voice-based audio communications over the Internet. The proposed mechanism was designed to dynamically adjust the talkspurt playout delays to the traffic conditions of the underlying network without assuming either the existence of an external mechanism for maintaining an accurate clock synchronization between the sender and the receiver during the audio communication, or a specific distribution of the audio packet transmission delays. Performance figures derived from several experiments are reported that illustrate the adequacy of the proposed mechanism in dynamically adjusting the audio packet playout delay to the network traffic conditions while maintaining a small percentage of packet loss. 相似文献
992.
Maurizio Addamo Vincenzo Augugliaro Marianna Bellardita Agatino Di Paola Vittorio Loddo Giovanni Palmisano Leonardo Palmisano Sedat Yurdakal 《Catalysis Letters》2008,121(1-2):58-62
X-ray photoelectron spectroscopy (XPS) has been applied to the study pertaining to preparation and characterization of catalysts
used in propylene polymerization. The analysis has indicated support/donor interaction in active support (adduct) and active
support/TiCl4 interaction during catalyst preparation process. A systematic study has been made to identify suitable adduct from a set
of three adducts for catalyst synthesis. Precise binding energy of Titanium species on catalyst surface has been measured
and its dispersion on support has been evaluated to correlate catalyst performance with the surface spectroscopic parameters. 相似文献
993.
994.
Costa Alberto; Peppe Antonella; Caltagirone Carlo; Carlesimo Giovanni Augusto 《Canadian Metallurgical Quarterly》2008,22(3):283
This study investigated prospective memory and its relationship to executive and memory functions in persons with Parkinson's disease (PD). Twenty-three individuals with PD and 25 healthy comparison participants participated in the study. In the prospective memory tasks, participants were asked to execute 3 actions after 20 min (time-based condition) or after a timer ring (event-based condition). A score was computed for the correct recall of the intention to perform the actions (prospective component) and for the correct execution of the actions (retrospective component). Participants with PD also received an extensive neuropsychological test battery. PD participants were less accurate than comparison participants in the prospective component of the time-based but not the event-based task. Individuals with PD were also impaired on the retrospective component of both tasks. In the PD group, a general trend toward significant correlations was found between performance level on the prospective memory component of the time-based task and scores on executive and working memory measures. These results document that prospective memory is impaired in PD possibly in relation to a dysregulation of cognitive functions associated with frontal systems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Gardini D Dondi M Costa AL Matteucci F Blosi M Galassi C Baldi G Cinotti E 《Journal of nanoscience and nanotechnology》2008,8(4):1979-1988
Nano-sized ceramic inks suitable for ink-jet printing have been developed for the four-colours CMYK (cyan, magenta, yellow, black) process. Nano-inks of different pigment composition (Co(1-x)O, Au(0), Ti(1-x-y)Sb(x)Cr(y)O2, CoFe2O4) have been prepared with various solid loadings and their chemicophysical properties (particle size, viscosity, surface tension, zeta-potential) were tailored for the ink-jet application. The pigment particle size is in the 20-80 nm range. All these nano-suspensions are stable for long time (i.e., several months) due to either electrostatic (high zeta-potential values) or steric stabilization mechanisms. Both nanometric size and high stability avoid problems of nozzle clogging from particles agglomeration and settling. Nano-inks have a Newtonian behaviour with relatively low viscosities at room temperature. More concentrated inks fulfil the viscosity requirement of ink-jet applications (i.e., < 35 mPa x s) for printing temperatures in between 30 and 70 degrees C. Surface tension constraints for ink-jet printing are fulfilled by nano-inks, being in the 35-45 mN x m(-1) range. The nano-sized inks investigated behave satisfactorily in preliminary printing tests on several unfired industrial ceramic tiles, developing saturated colours in a wide range of firing temperatures (1000-1200 degrees C). 相似文献
996.
Boschetti Giovanni Bottin Matteo Faccio Maurizio Minto Riccardo 《Journal of Intelligent Manufacturing》2021,32(5):1455-1470
Journal of Intelligent Manufacturing - In the last decade, collaborative assembly systems (CAS) are becoming increasingly common due to their ability to merge the flexibility of a manual assembly... 相似文献
997.
Giovanni Zarrilli Valentina Angerilli Gianluca Businello Marta Sbaraglia Giulia Traverso Francesco Fortarezza Stefania Rizzo Monica De Gaspari Cristina Basso Fiorella Calabrese Angelo Paolo Dei Tos Matteo Fassan 《International journal of molecular sciences》2021,22(2)
A complete understanding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) physiopathology and related histopathologic lesions is necessary to improve treatment and outcome of coronavirus disease 2019 (COVID-19) patients. Many studies have focused on autopsy findings in COVID-19-related deaths to try and define any possible specific pattern. Histopathologic alterations are principally found within lungs and blood vessels, and these abnormalities also seem to have the highest clinical impact. Nevertheless, many of the morphological data collected so far are non-specific, fickle, and possibly associated with other co-existing factors. The aim of this minireview is to describe the main histopathological features related to COVID-19 and the mechanism known as “cytokine storm”. 相似文献
998.
Paola Pontrelli Francesca Conserva Rossella Menghini Michele Rossini Alessandra Stasi Chiara Divella Viviana Casagrande Claudia Cinefra Mariagrazia Barozzino Simona Simone Francesco Pesce Giuseppe Castellano Giovanni Stallone Anna Gallone Francesco Giorgino Massimo Federici Loreto Gesualdo 《International journal of molecular sciences》2021,22(10)
Diabetic nephropathy (DN) is the most frequent cause of end-stage renal disease. Tubulointerstitial accumulation of lysine 63 (K63)-ubiquitinated (Ub) proteins is involved in the progression of DN fibrosis and correlates with urinary miR-27b-3p downregulation. We explored the renoprotective effect of an inhibitor of K63-Ub (NSC697923), alone or in combination with the ACE-inhibitor ramipril, in vitro and in vivo. Proximal tubular epithelial cells and diabetic DBA/2J mice were treated with NSC697923 and/or ramipril. K63-Ub protein accumulation along with α-SMA, collagen I and III, FSP-1, vimentin, p16INK4A expression, SA-α Gal staining, Sirius Red, and PAS staining were measured. Finally, we measured the urinary albumin to creatinine ratio (uACR), and urinary miR-27b-3p expression in mice. NSC697923, both alone and in association with ramipril, in vitro and in vivo inhibited hyperglycemia-induced epithelial to mesenchymal transition by significantly reducing K63-Ub proteins, α-SMA, collagen I, vimentin, FSP-1 expression, and collagen III along with tubulointerstitial and glomerular fibrosis. Treated mice also showed recovery of urinary miR-27b-3p and restored expression of p16INK4A. Moreover, NSC697923 in combination with ramipril demonstrated a trend in the reduction of uACR. In conclusion, we suggest that selective inhibition of K63-Ub, when combined with the conventional treatment with ACE inhibitors, might represent a novel treatment strategy to prevent the progression of fibrosis and proteinuria in diabetic nephropathy and we propose miR-27b-3p as a biomarker of treatment efficacy. 相似文献
999.
Patrizia Morciano Maria Laura Di Giorgio Liliana Tullo Giovanni Cenci 《International journal of molecular sciences》2021,22(11)
During spermatogenesis, the Golgi apparatus serves important roles including the formation of the acrosome, which is a sperm-specific organelle essential for fertilization. We have previously demonstrated that D. melanogaster ATP-dependent Citrate Lyase (ATPCL) is required for spindle organization, cytokinesis, and fusome assembly during male meiosis, mainly due to is activity on fatty acid biosynthesis. Here, we show that depletion of DmATPCL also affects the organization of acrosome and suggest a role for this enzyme in the assembly of Golgi-derived structures during Drosophila spermatogenesis. 相似文献
1000.
Maurizio Mennini Sofia Reddel Federica Del Chierico Simone Gardini Andrea Quagliariello Pamela Vernocchi Rocco Luigi Valluzzi Vincenzo Fierro Carla Riccardi Tania Napolitano Alessandro Giovanni Fiocchi Lorenza Putignani 《International journal of molecular sciences》2021,22(4)
Food allergy (FA) and, in particular, IgE-mediated cow’s milk allergy is associated with compositional and functional changes of gut microbiota. In this study, we compared the gut microbiota of cow’s milk allergic (CMA) infants with that of cow’s milk sensitized (CMS) infants and Healthy controls. The effect of the intake of a mixture of Bifidobacterium longum subsp. longum BB536, Bifidobacterium breve M-16V and Bifidobacterium longum subsp. infantis M-63 on gut microbiota modulation of CMA infants and probiotic persistence was also investigated. Gut microbiota of CMA infants resulted to be characterized by a dysbiotic status with a prevalence of some bacteria as Haemophilus, Klebsiella, Prevotella, Actinobacillus and Streptococcus. Among the three strains administered, B. longum subsp. infantis colonized the gastrointestinal tract and persisted in the gut microbiota of infants with CMA for 60 days. This colonization was associated with perturbations of the gut microbiota, specifically with the increase of Akkermansia and Ruminococcus. Multi-strain probiotic formulations can be studied for their persistence in the intestine by monitoring specific bacterial probes persistence and exploiting microbiota profiling modulation before the evaluation of their therapeutic effects. 相似文献