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81.
Corvin Rive Giacomo Reina Prerana Wagle Emanuele Treossi Vincenzo Palermo Alberto Bianco Lucia Gemma Delogu Matthias Rieckher Bjrn Schumacher 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(45)
Graphene oxide (GO) holds high promise for diagnostic and therapeutic applications in nanomedicine but reportedly displays immunotoxicity, underlining the need for developing functionalized GO with improved biocompatibility. This study describes adverse effects of GO and amino‐functionalized GO (GONH2) during Caenorhabditis elegans development and ageing upon acute or chronic exposure. Chronic GO treatment throughout the C. elegans development causes decreased fecundity and a reduction of animal size, while acute treatment does not lead to any measurable physiological decline. However, RNA‐Sequencing data reveal that acute GO exposure induces innate immune gene expression. The p38 MAP kinase, PMK‐1, which is a well‐established master regulator of innate immunity, protects C. elegans from chronic GO toxicity, as pmk‐1 mutants show reduced tissue‐functionality and facultative vivipary. In a direct comparison, GONH2 exposure does not cause detrimental effects in the wild type or in pmk‐1 mutants, and the innate immune response is considerably less pronounced. This work establishes enhanced biocompatibility of amino‐functionalized GO in a whole‐organism, emphasizing its potential as a biomedical nanomaterial. 相似文献
82.
Sara Sassetti Giacomo Marzi Vincenzo Cavaliere Cristiano Ciappei 《Scientometrics》2018,116(3):1675-1718
Research on entrepreneurial cognition (EC) has evolved in recent years, and the aim of this contribution is to offer a clear, systematic, and bibliometric review of EC as a field of study from a more dynamic perspective, building on Socially Situated Cognition theory (SSC). Based on a data set that covers 18 years of research, from 1998 to 2016, the present study analyzes all of the 151 papers available in the Web of Science Core Collection and 15 editorials, book chapters, and books directly referring to entrepreneurial cognition. Building on our results, we divided EC studies into two stages, namely the “emerging” (1998–2007) and the “mature” (2008–2016). In addition, with this study we suggest three main topics that should be investigated in future researches: entrepreneurial action should be considered endogenous in the entrepreneurship process and the studies in the field of embodied and distributed cognition should be expanded. 相似文献
83.
Electroactive Ionic Soft Actuators with Monolithically Integrated Gold Nanocomposite Electrodes
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Yunsong Yan Tommaso Santaniello Luca Giacomo Bettini Chloé Minnai Andrea Bellacicca Riccardo Porotti Ilaria Denti Gabriele Faraone Marco Merlini Cristina Lenardi Paolo Milani 《Advanced materials (Deerfield Beach, Fla.)》2017,29(23)
Electroactive ionic gel/metal nanocomposites are produced by implanting supersonically accelerated neutral gold nanoparticles into a novel chemically crosslinked ion conductive soft polymer. The ionic gel consists of chemically crosslinked poly(acrylic acid) and polyacrylonitrile networks, blended with halloysite nanoclays and imidazolium‐based ionic liquid. The material exhibits mechanical properties similar to that of elastomers (Young's modulus ≈ 0.35 MPa) together with high ionic conductivity. The fabrication of thin (≈100 nm thick) nanostructured compliant electrodes by means of supersonic cluster beam implantation (SCBI) does not significantly alter the mechanical properties of the soft polymer and provides controlled electrical properties and large surface area for ions storage. SCBI is cost effective and suitable for the scaleup manufacturing of electroactive soft actuators. This study reports the high‐strain electromechanical actuation performance of the novel ionic gel/metal nanocomposites in a low‐voltage regime (from 0.1 to 5 V), with long‐term stability up to 76 000 cycles with no electrode delamination or deterioration. The observed behavior is due to both the intrinsic features of the ionic gel (elasticity and ionic transport capability) and the electrical and morphological features of the electrodes, providing low specific resistance (<100 Ω cm?2), high electrochemical capacitance (≈mF g?1), and minimal mechanical stress at the polymer/metal composite interface upon deformation. 相似文献
84.
Gaetano Alfano Francesco Fontana Niccolò Morisi Francesco Giaroni Giacomo Mori Giovanni Guaraldi Riccardo Magistroni Gianni Cappelli Modena Covid- Working Group 《Hemodialysis international. International Symposium on Home Hemodialysis》2021,25(4):E53-E56
The immunological mechanisms that modulate immune response to SARS-CoV-2 infection remain elusive. Little is known on the magnitude and the durability of antibody response against COVID-19. There is consensus that patients with immune dysfunction, such as dialysis patients, may be unable to mount a robust and durable humoral immunity after infections. Recent studies showed that dialysis patients seroconverted after COVID-19, but data on the durability of the immune response are missing. We reported the data of a durable anti-spike protein seroconversion after natural SARS-CoV-2 infection in three patients on hemodialysis with a mean age of 67.2 ± 13.8 years. A mean antibody titer of 212.6 ± 174.9 UA/ml (Liaison®, DiaSorin) was found after one year (range, 366–374 days) from the diagnosis of COVID-19. In conclusion, this case series provided evidence that patients receiving hemodialysis who recovered from severe COVID-19 were able to mount a long-lasting immune response against SARS-CoV-2. Although the protective capacity of this long-term immunity remains to be determined, these patients did not report signs of reinfection after recovery from COVID-19. 相似文献
85.
Ciampi Francesco Giannozzi Alessandro Marzi Giacomo Altman Edward I. 《Scientometrics》2021,126(3):2141-2188
Scientometrics - Over the last dozen years, the topic of small and medium enterprise (SME) default prediction has developed into a relevant research domain that has grown for important reasons... 相似文献
86.
Daniele Costa Giacomo Palmieri Matteo-Claudio Palpacelli Luca Panebianco David Scaradozzi 《Journal of Intelligent and Robotic Systems》2018,91(2):181-192
The following paper presents the design and fabrication of an ostraciiform swimming robot and its navigation control and guidance system. Compared to other biomimetic vehicles, the chosen architecture has a lower propulsive efficiency but is easier to waterproof and capable to withstand greater pressures. To generate the alternating motion of the robot bio-inspired thruster, namely a plane fin, a transmission system was designed to replace the direct drive widely adopted in underwater biomimetic vehicles. The mechanical efficiency of two alternative mechanisms capable to actuate the fin were computed according to a preliminary sizing of the robot and its targeted swimming performances. Therefore, the more suitable solution was manufactured and installed aboard. At the same time, a proper navigation, guidance and control architecture (NGC) was designed and then integrated in the robot main controller. The proposed solution allows the vehicle to perform different missions autonomously once their profiles are received from the base station. Preliminary tests results and future works are discussed in the final conclusions. 相似文献
87.
Jakob Olofsson Riccardo Cenni Matteo Cova Giacomo Bertuzzi Kent Salomonsson Joel Johansson 《Structural and Multidisciplinary Optimization》2018,57(5):1889-1903
During the casting process and solidification of ductile iron castings, a heterogeneous microstructure is formed throughout the casting. This distribution is strongly influenced by the item geometry and the process related factors, as chemical composition and local solidification conditions. Geometrical changes to the geometry of the casting thus alters the local mechanical behavior and properties, as well as the distribution of stresses and strains when the casting is subjected to load. In order to find an optimal geometry, e.g. with reduced weight and increased load-bearing capacity, this interdependency between geometry and local material behavior needs to be considered and integrated into the optimization method. In this contribution, recent developments in the multidisciplinary integration of casting process simulation, solidification and microstructure modelling, microstructure-based material characterization, finite element structural analyses with local material behavior and structural optimization techniques are presented and discussed. The effect and relevance of considering the local material behavior in shape optimization of ductile iron castings is discussed and evidenced by an industrial application. It is shown that by adopting a multidisciplinary optimization approach by integration of casting simulation and local material behavior into shape optimization, the potential of the casting process to obtain components with high performance and reliability can be enabled and utilized. 相似文献
88.
Barbara Faccini Dario Di Giuseppe Giacomo Ferretti Massimo Coltorti Nicolò Colombani Micòl Mastrocicco 《Nutrient Cycling in Agroecosystems》2018,110(2):327-341
In this paper we report an overview of the main outcomes of a 3-years experimental cultivation carried out in an Italian reclaimed agricultural field amended with different types of zeolitites (rock containing > 50% of zeolites), under cereals cultivation (Sorghum vulgare Pers, Zea mays and Triticum durum). The aim of the experiment was to exploit the properties of zeolite-rich volcanic rocks (zeolitites) for reducing the excessively high NO3? content in the soil and in waters flowing out the sub-surface drainage system of the field and flushing into the surface water system, reducing concomitantly also chemical fertilization application rates (up to 50%). Zeolitites were tested both in their natural state and in a NH4+-enriched form, obtained through an enrichment process with NH4+-rich zoo-technical effluents (pig slurry). NO3? content in soils and in waters discharged through SSDS were periodically monitored during the experimentation and crop yield quantified. Results showed that, for three consecutive cultivation cycles, the overall NO3? concentrations in water extracts was reduced by 45% in the zeolitite treated soils, while in SSDS waters the reduction reached the 64%. Notwithstanding the lower N input from chemical fertilizers, crop yield was not negatively affected in the zeolitite amended soils with respect to the control. Zeolitite addition increased thus soil NH4+ retention and probably influenced several pathways of N losses, allowing a better fertilizer use efficiency by plants and a reduction of the overall NO3? concentrations in the surface waters. 相似文献
89.
Hybrid Photonic Nanostructures by In Vivo Incorporation of an Organic Fluorophore into Diatom Algae
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Roberta Ragni Francesco Scotognella Danilo Vona Luca Moretti Emiliano Altamura Giacomo Ceccone Dora Mehn Stefania R. Cicco Fabio Palumbo Guglielmo Lanzani Gianluca M. Farinola 《Advanced functional materials》2018,28(24)
Biotechnological processes harnessing living organisms' metabolism are low‐cost routes to nanostructured materials for applications in photonics, electronics, and nanomedicine. In the pursuit of photonic biohybrids, diatoms microalgae are attractive given the properties of the porous micro‐to‐nanoscale structures of the biosilica shells (frustules) they produce. The investigations have focused on in vivo incorporation of tailored molecular fluorophores into the frustules of Thalassiosira weissflogii diatoms, using a procedure that paves the way for easy biotechnological production of photonic nanostructures. The procedure ensures uniform staining of shells in the treated culture and permits the resulting biohybrid photonic nanostructures to be isolated with no damage to the dye and periodic biosilica network. Significantly, this approach ensures that light emission from the dye embedded in the isolated biohybrid silica is modulated by the silica's nanostructure, whereas no modulation of photoluminescence is observed upon grafting the fluorophore onto frustules by an in vitro approach based on surface chemistry. These results pave the way to the possibility of easy production of photonic nanostructures with tunable properties by simple feeding the diatoms algae with tailored photoactive molecules. 相似文献
90.
A methodology for the quantitative risk assessment of major accidents triggered by seismic events 总被引:2,自引:0,他引:2
A procedure for the quantitative risk assessment of accidents triggered by seismic events in industrial facilities was developed. The starting point of the procedure was the use of available historical data to assess the expected frequencies and the severity of seismic events. Available equipment-dependant failure probability models (vulnerability or fragility curves) were used to assess the damage probability of equipment items due to a seismic event. An analytic procedure was subsequently developed to identify, evaluate the credibility and finally assess the expected consequences of all the possible scenarios that may follow the seismic events. The procedure was implemented in a GIS-based software tool in order to manage the high number of event sequences that are likely to be generated in large industrial facilities. The developed methodology requires a limited amount of additional data with respect to those used in a conventional QRA, and yields with a limited effort a preliminary quantitative assessment of the contribution of the scenarios triggered by earthquakes to the individual and societal risk indexes. The application of the methodology to several case-studies evidenced that the scenarios initiated by seismic events may have a relevant influence on industrial risk, both raising the overall expected frequency of single scenarios and causing specific severe scenarios simultaneously involving several plant units. 相似文献