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81.
82.
Flora Amato Aniello Castiglione Vincenzo Moscato Antonio Picariello Giancarlo Sperlì 《Multimedia Tools and Applications》2018,77(14):17803-17827
In this work, we propose a novel multimedia summarization technique from Online Social Networks (OSNs). In particular, we model each Multimedia Social Network (MSN)—i.e. an OSN focusing on the management and sharing of multimedia information—using an hypergraph based approach and exploit influence analysis methodologies to determine the most important multimedia objects with respect to one or more topics of interest. Successively, we obtain from the list of candidate objects a multimedia summary using a summarization model together with an heuristics that aims to generate summaries with priority (with respect to some user keywords), continuity, variety and not receptiveness features. The performed experiments on Flickr shows the effectiveness of proposed approach. 相似文献
83.
Leonardo Rundo Carmelo Militello Giorgio Russo Salvatore Vitabile Maria Carla Gilardi Giancarlo Mauri 《Natural computing》2018,17(3):521-536
Despite of the development of advanced segmentation techniques, achieving accurate and reproducible gross tumor volume (GTV) segmentation results is still an important challenge in neuro-radiosurgery. Nowadays, magnetic resonance imaging (MRI) is the most prominent modality in radiation therapy for soft-tissue anatomical districts. Gamma Knife stereotactic neuro-radiosurgery is a minimally invasive technology for dealing with inaccessible or insufficiently treated tumors with traditional surgery or radiotherapy. During a treatment planning phase, the GTV is generally contoured by experienced neurosurgeons and radiation oncologists using fully manual segmentation procedures on MR images. Unfortunately, this operative methodology is definitely time-expensive and operator-dependent. Delineation result repeatability, in terms of both intra- and inter-operator reliability, can be achieved only by using computer-assisted approaches. In this paper a novel semi-automatic seeded image segmentation method, based on a cellular automata model, for MRI brain cancer detection and delineation is proposed. This approach, called GTVcut, employs an adaptive seed selection strategy and helps to segment the GTV, by identifying the target volume to be treated using the Gamma Knife device. The accuracy of GTVcut was evaluated on a dataset composed of 32 brain cancers, using both spatial overlap-based and distance-based metrics. The achieved experimental results are very reproducible, showing the effectiveness and the clinical feasibility of the proposed approach. 相似文献
84.
Guizzardi Giancarlo Sales Tiago Prince Almeida Joo Paulo A. Poels Geert 《Software and Systems Modeling》2022,21(4):1363-1387
Software and Systems Modeling - In recent years, there has been a growing interest in the use of reference conceptual models to capture information about complex and sensitive business domains... 相似文献
85.
Arlati Sara Keijsers Nol Paolini Gabriele Ferrigno Giancarlo Sacco Marco 《Virtual Reality》2022,26(3):885-901
Virtual Reality - Virtual reality (VR) has recently emerged as a promising technology to rehabilitate upper limb functions after stroke. To promote the recovery of functions, retraining... 相似文献
86.
Campo S Nastasi G D'Ascola A Campo GM Avenoso A Traina P Calatroni A Burrascano E Ferlazzo A Lupidi G Gabbianelli R Falcioni G 《The Science of the total environment》2008,403(1-3):148-153
In order to gain more knowledge on the stress responses of gilhead seabream (Sparus aurata) under extreme conditions, this study investigated the functional properties of the hemoglobin system and globin gene expression under hypoxia and low salinity. The oxygen affinity for the two hemoglobin components present inside the S. aurata erythrocyte was practically identical as was the influence of protons and organic phosphates (Root effect). The quantification of S. aurata hemoglobin fractions performed by HPLC and the data on gene expression of globin chains assayed by PCR indicate that under hypoxia and low salinity there is a change in the ratio between the two different hemoglobin components. The result indicating that the distinct hemoglobins present in S. aurata erythrocyte have almost identical functional properties, does not explain the adaptive response (expression change) following exposure of the animal to hypoxia or low salinity on the basis of their function as oxygen transporter. We hypothesize that other parallel biological functions that the hemoglobin molecule is known to display within the erythrocyte are involved in adaptive molecular mechanisms. The autoxidation-reduction cycle of hemoglobin could be involved in the response to particular living conditions. 相似文献
87.
State‐of‐the‐Art Neutral Tint Multichromophoric Polymers for High‐Contrast See‐Through Electrochromic Devices 下载免费PDF全文
Mauro Sassi Matteo M. Salamone Riccardo Ruffo Giorgio E. Patriarca Claudio M. Mari Giorgio A. Pagani Uwe Posset Luca Beverina 《Advanced functional materials》2016,26(29):5240-5246
Two new multichromophoric electrochromic polymers featuring a conjugated EDOT/ProDOT copolymer backbone (PXDOT) and a reversible Weitz‐type redox active small molecule electrochrome (WTE) tethered to the conjugated chain are reported here. The careful design of the WTEs provides a highly reversible redox behavior with a colorless red switching that complements the colorless blue switching of the conjugated backbone. Subtractive color mixing successfully provides high performing solution processable polymeric layers with colorless neutral tint switchable limiting states for application in see‐through electrochromic devices. Design, synthesis, comprehensive chemical and spectroelectrochemical characterization as well as the preparation of a proof‐of‐concept device are discussed. 相似文献
88.
Friddle RW Lemieux MC Cicero G Artyukhin AB Tsukruk VV Grossman JC Galli G Noy A 《Nature nanotechnology》2007,2(11):692-697
Carbon nanotubes display a consummate blend of materials properties that affect applications ranging from nanoelectronic circuits and biosensors to field emitters and membranes. These applications use the non-covalent interactions between the nanotubes and chemical functionalities, often involving a few molecules at a time. Despite their wide use, we still lack a fundamental understanding and molecular-level control of these interactions. We have used chemical force microscopy to measure the strength of the interactions of single chemical functional groups with the sidewalls of vapour-grown individual single-walled carbon nanotubes. Surprisingly, the interaction strength does not follow conventional trends of increasing polarity or hydrophobicity, and instead reflects the complex electronic interactions between the nanotube and the functional group. Ab initio calculations confirm the observed trends and predict binding force distributions for a single molecular contact that match the experimental results. Our analysis also reveals the important role of molecular linkage dynamics in determining interaction strength at the single functional group level. 相似文献
89.
Ezio Amerio Marco Sangermano Giulio Malucelli Aldo Priola Giancarlo Rizza 《大分子材料与工程》2006,291(10):1287-1292
Summary: Organic‐inorganic nanocomposite hybrid coatings were prepared through a dual‐cure process involving cationic photopolymerization of a hyperbranched epoxy functionalized resin and subsequent condensation of an alkoxysilane inorganic precursor. All the formulations investigated gave rise to photocured films characterized by high gel content values. An increase in glass transition temperature and an increase in storage modulus above Tg in the rubbery plateau is observed with increasing TEOS content in the photocurable formulation. The important role of GPTS on reducing the inorganic domain size and avoiding macroscopic phase separation was demonstrated by TEM analyses.
90.
We introduce an on-chip electrokinetic assay to perform high-sensitivity nucleic acid (NA) detection. This assay integrates electrokinetic sample focusing using isotachophoresis (ITP) with a background signal-removal strategy that employs photopatterened, DNA-functionalized hydrogels. In this multistage assay, ITP first enhances hybridization kinetics between target NAs and end-labeled complementary reporters. After enhanced hybridization, migration through a DNA-functionalized hydrogel region removes excess reporters through affinity interactions. We demonstrate our assay on microRNAs, an important class of low-abundance biomarkers. The assay exhibits 4 orders of magnitude dynamic range, near 1 pM detection limits starting from less than 100 fg of microRNA, and high selectivity for mature microRNA sequences, all within a 10 min run time. This new microfluidic framework provides a unique quantitative assay for NA detection. 相似文献