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81.
Carlo Bonini Maurizio D'Auria Lucia Emanuele Rachele Ferri Rachele Pucciariello Anna Rita Sabia 《应用聚合物科学杂志》2005,98(3):1451-1456
Lignin, obtained through steam explosion from straw, was completely characterized via elemental analysis, gel permeation chromatography, ultraviolet and infrared spectroscopy, and 13C and 1H nuclear magnetic resonance spectrometry. Polyurethanes were obtained by treating steam‐exploded lignin from straw with 4,4′‐methylenebis(phenylisocyanate), 4,4′‐methylenebis(phenylisocyanate) –ethandiol, and poly(1,4‐butandiol)tolylene‐2,4‐diisocyanate terminated. The obtained materials were characterized by using gel permeation chromatography, infrared spectroscopy, and scanning electron microscopy. Differential scanning calorimetry analysis showed a Tg at ?6°C, assigned to the glass transition of the poly(1,4‐butandiol) chains. The presence of ethylene glycol reduced the yields of the polyurethanes. The use of the prepolymer gave the best results in polyurethane formation. Steam‐exploded lignin was used as the starting material in the synthesis of polyesters. Lignin was treated with dodecanoyl dichloride. The products were characterized by using gel permeation chromatography, infrared spectroscopy, 13C and 1H nuclear magnetic resonance spectrometry, and scanning electron microscopy. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1451–1456, 2005 相似文献
82.
Libertini Giacinto; Donato Alberto Di 《Protein engineering, design & selection : PEDS》1992,5(8):821-825
A computer program, which runs on MS-DOS personal computers,is described that assists in the design of synthetic genes codingfor proteins. The goal of the program is the design of a genewhich (0 contains as many unique restriction sites as possibleand (ii) uses a specific codon usage. The gene designed accordingto the criteria above is (i) suitable for modular mutagenesisexperiments and (ii) optimized for expression. The program 'reverse-translates'protein sequences into degenerated DNA sequences, generatesa map of potential restriction sites and locates sequence positionswhere unique restriction sites can be accommodated. The nucleicacid sequence is then refined according to a specificcodon usage to remove any degeneration. Unique restriction sites,if potentially present, can be forced into thedegenerated nucleic acid sequence by using 'priority codes'assigned to different restriction sequences. 相似文献
83.
Giuseppe Aceto Alessio Botta Walter de Donato Antonio Pescapè 《Computer Networks》2013,57(9):2093-2115
Nowadays, Cloud Computing is widely used to deliver services over the Internet for both technical and economical reasons. The number of Cloud-based services has increased rapidly and strongly in the last years, and so is increased the complexity of the infrastructures behind these services. To properly operate and manage such complex infrastructures effective and efficient monitoring is constantly needed.Many works in literature have surveyed Cloud properties, features, underlying technologies (e.g. virtualization), security and privacy. However, to the best of our knowledge, these surveys lack a detailed analysis of monitoring for the Cloud. To fill this gap, in this paper we provide a survey on Cloud monitoring. We start analyzing motivations for Cloud monitoring, providing also definitions and background for the following contributions. Then, we carefully analyze and discuss the properties of a monitoring system for the Cloud, the issues arising from such properties and how such issues have been tackled in literature. We also describe current platforms, both commercial and open source, and services for Cloud monitoring, underlining how they relate with the properties and issues identified before. Finally, we identify open issues, main challenges and future directions in the field of Cloud monitoring.1 相似文献
84.
85.
Maria Teresa Valenti Luca Dalle Carbonare Donato Zipeto Monica Mottes 《International journal of molecular sciences》2021,22(5)
Autophagy is involved in different degenerative diseases and it may control epigenetic modifications, metabolic processes, stem cells differentiation as well as apoptosis. Autophagy plays a key role in maintaining the homeostasis of cartilage, the tissue produced by chondrocytes; its impairment has been associated to cartilage dysfunctions such as osteoarthritis (OA). Due to their location in a reduced oxygen context, both differentiating and mature chondrocytes are at risk of premature apoptosis, which can be prevented by autophagy. AutophagomiRNAs, which regulate the autophagic process, have been found differentially expressed in OA. AutophagomiRNAs, as well as other regulatory molecules, may also be useful as therapeutic targets. In this review, we describe and discuss the role of autophagy in OA, focusing mainly on the control of autophagomiRNAs in OA pathogenesis and their potential therapeutic applications. 相似文献
86.
Leôncio Diógenes T. Câmara Rafael S. Monteiro Alex M. Constantino Donato A. G. Aranda Júlio C. Afonso 《Chemical Engineering Communications》2013,200(3):416-424
This work describes the oxidative cracking of n-alkanes with molecular oxygen at low temperatures (below 473 K) in an autoclave reactor. An increase of the oxygen consumption rate with increasing hydrocarbon size was observed. Data for n-hexadecane indicate that oxidative cracking is an autocatalytic reaction. The oxidation rate increased with the progress of the reaction. Low molecular weight compounds were formed as the main products. CG and CG-MS analyses of the liquid products found homologous series of oxygen compounds (acids, ketones, and ethers) and short-chain n-alkanes. Our results strongly suggest that oxidative cracking can be employed for processing heavy materials such as polymers and petroleum residues. 相似文献
87.
Lorenzo Indennidate Donato Cannoletta Francesca Lionetto Antonio Greco Alfonso Maffezzoli 《Polymer International》2010,59(4):486-491
The use of polyether polyols is common in polyurethane industry, particularly in soft PU applications. In particular, viscoelastic foams, characterized by slow recovery after compression, are obtained using poly(ethylene oxide) (PEO) polyols. Nanofilled polyols can be used for the production of viscoelastic foams with improved fire resistance properties. The high polarity of polyether polyols is responsible of a poor affinity with the organic modifiers used in commercial organically modified montmorillonite (omMMT). In this work, organically modified montmorillonites were prepared, having an improved affinity with the polyether polyols used for the production of soft PU foams. The montmorillonite was modified by using polyetheramines with different ethyleneoxide/propyleneoxide amounts. A strongly intercalated/exfoliated structure was obtained after mixing the polyol with the omMMT. The viscosity increased by three orders of magnitude and the diffraction angles of the MMT measured by x‐ray analysis decreased to values lower than 1.5°. The intercalated structure was preserved after the curing stage, when the isocyanate was added to the polyol/omMMT. The resulting polyurethane had an irregular open cell structure, and was characterized by a mechanical properties comparable to those of unfilled polyurethane. Copyright © 2009 Society of Chemical Industry 相似文献
88.
Silvia Cerri Cristina Ghezzi Gerardo Ongari Stefania Croce Micol Avenali Roberta Zangaglia Donato A. Di Monte Enza Maria Valente Fabio Blandini 《International journal of molecular sciences》2021,22(4)
Heterozygous mutations in the GBA gene, encoding the lysosomal enzyme glucocerebrosidase (GCase), are the strongest known genetic risk factor for Parkinson’s disease (PD). The molecular mechanisms underlying the increased PD risk and the variable phenotypes observed in carriers of different GBA mutations are not yet fully elucidated. Extracellular vesicles (EVs) have gained increasing importance in neurodegenerative diseases since they can vehiculate pathological molecules potentially promoting disease propagation. Accumulating evidence showed that perturbations of the endosomal–lysosomal pathway can affect EV release and composition. Here, we investigate the impact of GCase deficiency on EV release and their effect in recipient cells. EVs were purified by ultracentrifugation from the supernatant of fibroblast cell lines derived from PD patients with or without GBA mutations and quantified by nanoparticle tracking analysis. SH-SY5Y cells over-expressing alpha-synuclein (α-syn) were used to assess the ability of patient-derived small EVs to affect α-syn expression. We observed that defective GCase activity promotes the release of EVs, independently of mutation severity. Moreover, small EVs released from PD fibroblasts carrying severe mutations increased the intra-cellular levels of phosphorylated α-syn. In summary, our work shows that the dysregulation of small EV trafficking and alpha-synuclein mishandling may play a role in GBA-associated PD. 相似文献
89.
Giovanni Ambrosi Simona Bartocci Laurent Basara Roberto Battiston William J. Burger Luca Carfora Guido Castellini Piero Cipollone Livio Conti Andrea Contin Cinzia De Donato Cristian De Santis Francesco M. Follega Cristina Guandalini Maria Ionica Roberto Iuppa Giuliano Laurenti Ignazio Lazzizzera Mauro Lolli Christian Manea Laura Marcelli Giuseppe Masciantonio Matteo Mergé Giuseppe Osteria Lorenzo Pacini Francesco Palma Federico Palmonari Beatrice Panico Laura Patrizii Francesco Perfetto Piergiorgio Picozza Michele Pozzato Matteo Puel Irina Rashevskaya Ester Ricci Marco Ricci Sergio Bruno Ricciarini Valentina Scotti Alessando Sotgiu Roberta Sparvoli Bruno Spataro Vincenzo Vitale 《中国科学:技术科学(英文版)》2018,61(5):643-652
CSES(China Seismo-Electromagnetic Satellite) is a mission developed by CNSA(Chinese National Space Administration) and ASI(Italian Space Agency), to investigate the near-Earth electromagnetic, plasma and particle environment, for studying the seismo-associated disturbances in the ionosphere-magnetosphere transition zone. The anthropogenic and electromagnetic noise,as well as the natural non-seismic electromagnetic emissions is mainly due to tropospheric activity. In particular, the mission aims to confirming the existence of possible temporal correlations between the occurrence of earthquakes for medium and strong magnitude and the observation in space of electromagnetic perturbations, plasma variations and precipitation of bursts with highenergy charged particles from the inner Van Allen belt. In this framework, the high energy particle detector(HEPD) of the CSES mission has been developed by the Italian LIMADOU Collaboration. HEPD is an advanced detector based on a tower of scintillators and a silicon tracker that provides good energy and angular resolution and a wide angular acceptance, for electrons of 3–100 Me V, protons of 30–200 Me V and light nuclei up to the oxygen. CSES satellite has been launched on February 2~(nd), 2018 from the Jiuquan Satellite Launch Center(China). 相似文献
90.
G. Messina V. Modafferi S. Santangelo P. Tripodi M.G. Donato M. Lanza S. Galvagno C. Milone E. Piperopoulos A. Pistone 《Diamond and Related Materials》2008,17(7-10):1482-1488
The crucial role of precursor gas (PG) and of catalyst support (CS) in the growth of multi-walled C nanotubes (MWCNTs) by iron-catalysed chemical vapour deposition (CVD) is evidenced. This is accomplished by comparing structural and morphological properties of MWCNTs synthesised by the use of different PGs (ethane and isobutane) and CSs (silica and alumina). The results of analyses, carried out on catalysts and C deposits by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy (RS), thermo-gravimetry (TG) and X-ray diffraction (XRD), demonstrate that Al2O3-supported catalysts are more efficient than SiO2-supported ones in decomposing hydrocarbons. The use of i-C4H10 as PG allows reducing Fe-encapsulation and improving yield (YC) and selectivity, so as the large-scale production (YC > 900 wt.%) of high-quality nanotubes can be operated even at moderate reaction temperature (600 °C) after proper calibration of Fe-load (29 wt.%) and catalyst reduction temperature (500 °C). 相似文献