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排序方式： 共有520条查询结果，搜索用时 15 毫秒
51.
Giovanni Nava Luca Casiraghi Thomas Carzaniga Giuliano Zanchetta Marcella Chiari Francesco Damin Valentina Bollati Lucia Signorini Serena Delbue Tommaso Bellini Marco Buscaglia 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(32):2300947
Rapid detection of whole virus particles in biological or environmental samples represents an unmet need for the containment of infectious diseases. Here, an optical device enabling the enumeration of single virion particles binding on antibody or aptamers immobilized on a surface with anti-reflective coating is described. In this regime, nanoparticles adhering to the sensor surface provide localized contributions to the reflected field that become detectable because of their mixing with the interfering waves in the reflection direction. Thus, these settings are exploited to realize a scan-free, label-free, micro-array-type digital assay on a disposable cartridge, in which the virion counting takes place in wide field-of-view imaging. With this approach we could quantify, by enumeration, different variants of SARS-CoV-2 virions interacting with antibodies and aptamers immobilized on different spots. For all tested variants, the aptamers showed larger affinity but lower specificity relative to the antibodies. It is found that the combination of different probes on the same surface enables increasing specificity of detection and dynamic range. 相似文献
52.
Boris V. Sorokin Marina Pivetta Valerio Bellini Darius Merk Sébastien Reynaud Alessandro Barla Harald Brune Stefano Rusponi 《Advanced functional materials》2023,33(20):2213951
X-ray magnetic circular dichroism, atomic multiplet simulations, and density functional theory calculations are employed to identify criteria for the optimum combination of supporting alkaline earth oxide and adsorption site maximizing the spin lifetimes of lanthanide single-atom magnets. Dy and Ho atoms adsorbed on BaO(100) thin films on Pt(100) are characterized and compared with previous results for the same two elements on MgO/Ag(100). Dy shows hysteresis in magnetic fields up to ≈3.5 T and long spin lifetime, exceeding 300 s at 2.5 K and 0.5 T. Dy displays superior magnetic stability on the bridge site than on the top-O site. Surprisingly, Ho shows paramagnetism, as opposed to its long spin lifetime on MgO. These differences originate from the local surface distortions induced by the adatoms. On MgO, minimal distortions involve only the closest O atoms, while, on BaO, they affect both the closest anions and cations. This trend reflects the decrease of the lattice energy along the series of the alkaline earth oxides, going from MgO to BaO. This study represents a step ahead in the understanding of the factors determining the spin dynamics of surface-adsorbed single-atom magnets in order to achieve their operation as qubits and memories. 相似文献
53.
Nico Curti Yuri Merli Corrado Zengarini Enrico Giampieri Alessandra Merlotti Daniele Dall&#x;Olio Emanuela Marcelli Tommaso Bianchi Gastone Castellani 《International journal of molecular sciences》2023,24(1)
Appropriate wound management shortens the healing times and reduces the management costs, benefiting the patient in physical terms and potentially reducing the healthcare system’s economic burden. Among the instrumental measurement methods, the image analysis of a wound area is becoming one of the cornerstones of chronic ulcer management. Our study aim is to develop a solid AI method based on a convolutional neural network to segment the wounds efficiently to make the work of the physician more efficient, and subsequently, to lay the foundations for the further development of more in-depth analyses of ulcer characteristics. In this work, we introduce a fully automated model for identifying and segmenting wound areas which can completely automatize the clinical wound severity assessment starting from images acquired from smartphones. This method is based on an active semi-supervised learning training of a convolutional neural network model. In our work, we tested the robustness of our method against a wide range of natural images acquired in different light conditions and image expositions. We collected the images using an ad hoc developed app and saved them in a database which we then used for AI training. We then tested different CNN architectures to develop a balanced model, which we finally validated with a public dataset. We used a dataset of images acquired during clinical practice and built an annotated wound image dataset consisting of 1564 ulcer images from 474 patients. Only a small part of this large amount of data was manually annotated by experts (ground truth). A multi-step, active, semi-supervised training procedure was applied to improve the segmentation performances of the model. The developed training strategy mimics a continuous learning approach and provides a viable alternative for further medical applications. We tested the efficiency of our model against other public datasets, proving its robustness. The efficiency of the transfer learning showed that after less than 50 epochs, the model achieved a stable DSC that was greater than 0.95. The proposed active semi-supervised learning strategy could allow us to obtain an efficient segmentation method, thereby facilitating the work of the clinician by reducing their working times to achieve the measurements. Finally, the robustness of our pipeline confirms its possible usage in clinical practice as a reliable decision support system for clinicians. 相似文献
54.
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
55.
Tommaso Taddei James D Penn Anthony T Patera 《International journal for numerical methods in engineering》2017,112(13):2135-2150
We present and analyze a validation procedure for a given state estimate u ? of the true field u true based on Monte Carlo sampling of experimental observation functionals. Our method provides, given a set of N possibly noisy local experimental observation functionals over the spatial domain Ω, confidence intervals for the L 2(Ω) error in state and the error in L 2(Ω) outputs. For L 2(Ω) outputs, our approach also provides a confidence interval for the output itself, which can be used to improve the initial output estimate based on u ?. Our approach implicitly takes advantage of variance reduction, through the proximity of u ? to u true, to provide tight confidence intervals even for modest values of N . We present results for a synthetic model problem to illustrate the elements of the methodology and confirm the numerical properties suggested by the theory. Finally, we consider an experimental thermal patch configuration to demonstrate the applicability of our approach to real physical systems. 相似文献
56.
Alessandro Guidotti Alessandro Vanelli‐Coralli Tommaso Foggi Giulio Colavolpe Mrius Caus Joan Bas Stefano Cioni Andrea Modenini 《International Journal of Satellite Communications and Networking》2019,37(4):316-330
The integration of satellite and terrestrial networks is a promising solution for extending broadband coverage to areas not connected to a terrestrial infrastructure, as also demonstrated by recent commercial and standardisation endeavours. However, the large delays and Doppler shifts over the satellite channel pose severe technical challenges to traditional terrestrial systems, as long‐term evolution (LTE) or 5G. In this paper, 2 architectures are proposed for a low Earth orbit mega‐constellation realising a satellite‐enabled LTE system, in which the on‐ground LTE entity is either an eNB (Sat‐eNB) or a relay node (Sat‐RN). The impact of satellite channel impairments as large delays and Doppler shifts on LTE PHY/MAC procedures is discussed and assessed. The proposed analysis shows that, while carrier spacings, random access and RN attach procedures do not pose specific issues and hybrid automatic repeat request requires substantial modifications. Moreover, advanced handover procedures will be also required due to the satellites' movement. 相似文献
57.
Elena Pellizzoni Daniel Trabucchi Tommaso Buganza 《Creativity & Innovation Management》2019,28(4):464-476
Open Innovation is a leading paradigm in the current landscape, and scholars have been highly focused on defining the characteristics and capabilities that firms need to implement it successfully. This research aims to understand how organizations may implement inbound OI projects. Relying on a multiple case study approach and based on primary and secondary sources, this research highlights two main approaches: team‐centred and individual‐centred. The two approaches are discussed according to previous studies, highlighting how the first one is particularly coherent with previous research on Open Innovation, while the second one offers great insights from an Agile Project Management perspective. In particular, this research suggests how the Open Innovation literature can be enriched by considering the recent advancements in the Agile literature, valuing the individual and its autonomy to embrace external ideas from an OI perspective. 相似文献
58.
AN ENERGY ANALYSIS OF BELT POLISHING PROCESS AND ITS APPLICATIONS TO TIME CYCLE AND TRACKING EFFECTS 总被引：1，自引：0，他引：1
Edoardo Sura Mohamed El Mansori Patrick Ghidossi Stephane Deblaise Tommaso Dal Negro Hatem Khanfir 《Machining Science and Technology》2007,11(2):217-234
Belt polishing is a fine machining process widely used to improve surface texture and to increase wear resistance and fatigue life. Despite the basics of this manufacturing process are not yet well understood, the cycle-time and the belt oscillations frequency are considered as fundamental process variables. In this article, their effects on the surface characterization and on the form aspects are investigated in connection with the principal physical mechanisms activated during the superfinishing operations (cutting, ploughing and sliding). With this aim, an energy approach of the belt polishing process, coupled with SEM observations of the abrasive belt, is introduced. Two belt polishing energetic regimes are identified and then discussed. 相似文献
59.
认为web3.0和社交网络会让我们摆脱在公共空间中进行物理交流需求的想法需要再斟酌。事实上,当环境中的技术设施让我们能够用负担得起的可移动设备与世界相联系、让新的工作和社交模式能够在家里甚至喜爱的酒吧中产生的时候,很多在家工作的人和网友开始感受到一种需要重新建立起某些真正的社会团体的需求。因此很容易理解,在过去的几十年中,许多城市成为一种合作机制网络成长的摇篮。合作机制是一种实验,为喜欢与他人共享空间的人们提供廉价、灵活和非正规的生活和工作的解决方案。更准确地说,分享是这些措施中可持续性的关键,因为仅仅通过让一个 相似文献
60.
Environmental heterogeneity patterns and assessment of trophic levels in two Mediterranean lagoons: Orbetello and Varano, Italy 总被引：1，自引：0，他引：1
Specchiulli A Focardi S Renzi M Scirocco T Cilenti L Breber P Bastianoni S 《The Science of the total environment》2008,402(2-3):285-298
The management of coastal lagoons is of particular interest due to their high economical importance. In spite of their great productivity, coastal lagoons are often impacted by human pressure which produces water eutrophication. The aim of this paper is to assess the trophic state of the two Mediterranean lagoons taking into account chemical-physical parameters, nutrient concentrations and biological parameters. Two Italian lagoons, Orbetello and Varano (respectively located in Tyrrhenian and Adriatic coast, Italy) were studied between May 2003 and April 2005. Both these systems receive treated urban outflows, agricultural effluents and rivers freshwater inputs. Field collected data showed that studied lagoons were characterized by different human and natural pressures. Orbetello showed the highest water eutrophication, highlighted by the trophic index values, while Varano showed lower eutrophication levels except for the summertime. The values of physical, chemical and biological parameters measured in Orbetello and Varano lagoons indicate that a wide spatial and seasonal gradient of the water characteristics was established during the study period, but in particular in winter. This gradient, typical of estuarine systems, was essentially due to the mixing of freshwater, seawater and anthropogenic inputs. Orbetello lagoon seemed much more affected by the urban impact and the fish-farming activities than Varano lagoon, but the latter showed a greater agriculture activities impact as showed by the remote sensing images. 相似文献