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991.
Roberta Cassano Maria Luisa Di Gioia Silvia Mellace Nevio Picci Sonia Trombino 《Journal of materials science. Materials in medicine》2017,28(12):190
This work concerns on the preparation and performance evaluation of a new chitosan hydroquinone based gauze for hemostatic use. Chitosan and hydroquinone were firstly connected by etherification and then linked to the pre-carboxylate gauze. The functionalized material and the chitosan-hydroquinone ether were characterized by Fourier Transform Infrared (FT-IR) Spectroscopy and Differential Scanning Calorimetry (DSC). FT-IR results showed that an esterification occurred on carboxylic group of the gauze. The gauze functionalization degree was also evaluated by volumetric analysis. The ether hydroquinone content was obtained by the Folin test. Moreover, the linkage between hydroquinone and chitosan was confirmed by nuclear magnetic resonance (NMR). The hemostatic activity of functionalized gauze was evaluated by dynamic blood clotting assays. The obtained results showed that the prepared material can shorten the blood clotting time and induce the adhesion and activation of platelets. Finally, swelling characteristic of the new gauze was evaluated to confirm its high capacity to absorb the blood. 相似文献
992.
The concept of collaborative networks has attracted considerable attention, especially in two knowledge domains: innovation and operation management. Although collaborative networks have evolved into many forms, their central role in triggering debates has not gone unnoticed. In this paper, we aim to contribute to these debates through a bibliometric review of a decade of research on collaborative networks (2002–2015). By using a combination of document co-citation and bibliographic coupling analyses, we unveil the origins and evolution of collaborative networks over time by analysing the references from the most important academic contributions. Our goal is threefold: first, to systematise the state of the art in the Input-Process-Output (IPO) framework; second, to elucidate the antecedents of the research field on collaborative networks (research streams originating from the field, main authors and journals) by organising them in six thematic clusters; and third, to show how the antecedents shaped the IPO framework. While ‘collaborative networks’ used to belong to two distinct domains, the research agendas seem to converge because of the interactions between their most active authors. As such, cross-fertilisation occurs with the International Journal of Production Research, which plays a central role in this process. 相似文献
993.
A Novel Top‐Down Synthesis of Ultrathin 2D Boron Nanosheets for Multimodal Imaging‐Guided Cancer Therapy 下载免费PDF全文
Xiaoyuan Ji Na Kong Junqing Wang Wenliang Li Yuling Xiao Silvia Tian Gan Ye Zhang Yujing Li Xiangrong Song Qingqing Xiong Sanjun Shi Zhongjun Li Wei Tao Han Zhang Lin Mei Jinjun Shi 《Advanced materials (Deerfield Beach, Fla.)》2018,30(36)
Single atom nonmetal 2D nanomaterials have shown considerable potential in cancer nanomedicines, owing to their intriguing properties and biocompatibility. Herein, ultrathin boron nanosheets (B NSs) are prepared through a novel top‐down approach by coupling thermal oxidation etching and liquid exfoliation technologies, with controlled nanoscale thickness. Based on the PEGylated B NSs, a new photonic drug delivery platform is developed, which exhibits multiple promising features for cancer therapy and imaging, including: i) efficient NIR‐light‐to‐heat conversion with a high photothermal conversion efficiency of 42.5%, ii) high drug‐loading capacity and triggered drug release by NIR light and moderate acidic pH, iii) strong accumulation at tumor sites, iv) multimodal imaging properties (photoacoustic, photothermal, and fluorescence imaging), and v) complete tumor ablation and excellent biocompatibility. As far as it is known, this is the first report on the top‐down fabrication of ultrathin 2D B NSs by the combined thermal oxidation etching and liquid exfoliation, as well as their application as a multimodal imaging‐guided drug delivery platform. The newly prepared B NSs are also expected to provide a robust and useful 2D nanoplatform for various biomedical applications. 相似文献
994.
Delayed renal dysfunction and flash pulmonary edema post endovascular abdominal aneurysm repair 下载免费PDF全文
Pierre‐Louis Carron Nicolas Piliero Morgane Heitz Marc Kribs Mathieu Rodière Patrick Jousse Silvia Gunther‐Calvino Frédéric Thony 《Hemodialysis international. International Symposium on Home Hemodialysis》2016,20(2):E5-E7
After endovascular aortic repair (EVAR), the deterioration in long‐term renal function is probably multifactorial. Preoperative renal failure is an independent risk factor. Postoperative renal dysfunction can be associated with inadvertent renal artery occlusion, renal artery complications as stenosis, plaque dislodgement, or dissection. Ischemic nephropathy can accelerate hypertension and circulatory congestion. We report a case of coverage of the renal arteries symptomatic with flash pulmonary edema and renal failure 15 months after EVAR, suggesting a delayed endograft migration. The patient had complete resolution of symptoms and renal function after renal artery stenting with placement between endograft and aneurysm to the left renal artery. 相似文献
995.
Gianluca Nastasi Valentina Colla Silvia Cateni Simone Campigli 《Journal of Intelligent Manufacturing》2018,29(7):1545-1557
The paper presents strategies optimization for an existing automated warehouse located in a steelmaking industry. Genetic algorithms are applied to this purpose and three different popular algorithms capable to deal with multi-objective optimization are compared. The three algorithms, namely the Niched Pareto Genetic Algorithm, the Non-dominated Sorting Genetic Algorithm 2 and the Strength Pareto Genetic Algorithm 2, are described in details and the achieved results are widely discussed; moreover several statistical tests have been applied in order to evaluate the statistical significance of the obtained results. 相似文献
996.
Dimensionality reduction (DR) has been one central research topic in information theory, pattern recognition, and machine learning. Apparently, the performance of many learning models significantly rely on dimensionality reduction: successful DR can largely improve various approaches in clustering and classification, while inappropriate DR may deteriorate the systems. When applied on high-dimensional data, some existing research approaches often try to reduce the dimensionality first, and then input the reduced features to other available models, e.g., Gaussian mixture model (GMM). Such independent learning could however significantly limit the performance, since the optimal subspace given by a particular DR approach may not be appropriate for the following model. In this paper, we focus on investigating how unsupervised dimensionality reduction could be performed together with GMM and if such joint learning could lead to improvement in comparison with the traditional unsupervised method. In particular, we engage the mixture of factor analyzers with the assumption that a common factor loading exists for all the components. Based on that, we then present EM-algorithm that converges to a local optimal solution. Such setting exactly optimizes a dimensionality reduction together with the parameters of GMM. We describe the framework, detail the algorithm, and conduct a series of experiments to validate the effectiveness of our proposed approach. Specifically, we compare the proposed joint learning approach with two competitive algorithms on one synthetic and six real data sets. Experimental results show that the joint learning significantly outperforms the comparison methods in terms of three criteria. 相似文献
997.
Wesley K. G. Assunção Roberto E. Lopez-Herrejon Lukas Linsbauer Silvia R. Vergilio Alexander Egyed 《Empirical Software Engineering》2017,22(6):2972-3016
Software Product Lines (SPLs) are families of systems that share common assets allowing a disciplined reuse. Rarely SPLs start from scratch, instead they usually start from a set of existing systems that undergo a reengineering process. Many approaches to conduct the reengineering process have been proposed and documented in research literature. This scenario is a clear testament to the interest in this research area. We conducted a systematic mapping study to provide an overview of the current research on reengineering of existing systems to SPLs, identify the community activity in regarding of venues and frequency of publications in this field, and point out trends and open issues that could serve as references for future research. This study identified 119 relevant publications. These primary sources were classified in six different dimensions related to reengineering phases, strategies applied, types of systems used in the evaluation, input artefacts, output artefacts, and tool support. The analysis of the results points out the existence of a consolidate community on this topic and a wide range of strategies to deal with different phases and tasks of the reengineering process, besides the availability of some tools. We identify some open issues and areas for future research such as the implementation of automation and tool support, the use of different sources of information, need for improvements in the feature management, the definition of ways to combine different strategies and methods, lack of sophisticated refactoring, need for new metrics and measures and more robust empirical evaluation. Reengineering of existing systems into SPLs is an active research topic with real benefits in practice. This mapping study motivates new research in this field as well as the adoption of systematic reuse in software companies. 相似文献
998.
Silvia Puglisi David Rebollo-Monedero Jordi Forné 《International Journal of Parallel, Emergent and Distributed Systems》2017,32(5):502-521
On today’s Web, users trade access to their private data for content and services. App and service providers want to know everything they can about their users, in order to improve their product experience. Also, advertising sustains the business model of many websites and applications. Efficient and successful advertising relies on predicting users’ actions and tastes to suggest a range of products to buy. Both service providers and advertisers try to track users’ behaviour across their product network. For application providers this means tracking users’ actions within their platform. For third-party services following users, means being able to track them across different websites and applications. It is well known how, while surfing the Web, users leave traces regarding their identity in the form of activity patterns and unstructured data. These data constitute what is called the user’s online footprint. We analyse how advertising networks build and collect users footprints and how the suggested advertising reacts to changes in the user behaviour. 相似文献
999.
Benjamin Köhler Silvia Born Roy F. P. van Pelt Anja Hennemuth Uta Preim Bernhard Preim 《Computer Graphics Forum》2017,36(6):5-35
Cardiac four‐dimensional phase‐contrast magnetic resonance imaging (4D PC‐MRI) acquisitions have gained increasing clinical interest in recent years. They allow to non‐invasively obtain extensive information about patient‐specific hemodynamics, and thus have a great potential to improve the diagnosis, prognosis and therapy planning of cardiovascular diseases. A dataset contains time‐resolved, three‐dimensional blood flow directions and strengths, making comprehensive qualitative and quantitative data analysis possible. Quantitative measures, such as stroke volumes, help to assess the cardiac function and to monitor disease progression. Qualitative analysis allows to investigate abnormal flow characteristics, such as vortices, which are correlated to different pathologies. Processing the data comprises complex image processing methods, as well as flow analysis and visualization. In this work, we mainly focus on the aorta. We provide an overview of data measurement and pre‐processing, as well as current visualization and quantification methods. This allows other researchers to quickly catch up with the topic and take on new challenges to further investigate the potential of 4D PC‐MRI data. 相似文献
1000.
Silvia Ghilezan Svetlana Jakšić Jovanka Pantović Jorge A. Pérez Hugo Torres Vieira 《Formal Aspects of Computing》2016,28(4):643-667
Protocols in distributed settings usually rely on the interaction of several parties and often identify the roles involved in communications. Roles may have a behavioral interpretation, as they do not necessarily correspond to sites or physical devices. Notions of role authorization thus become necessary to consider settings in which, e.g., different sites may be authorized to act on behalf of a single role, or in which one site may be authorized to act on behalf of different roles. This flexibility must be equipped with ways of controlling the roles that the different parties are authorized to represent, including the challenging case in which role authorizations are determined only at runtime. We present a typed framework for the analysis of multiparty interaction with dynamic role authorization and delegation. Building on previous work on conversation types with role assignment, our formal model is based on an extension of the \({\pi}\)-calculus in which the basic resources are pairs channel-role, which denote the access right of interacting along a given channel representing the given role. To specify dynamic authorization control, our process model includes (1) a novel scoping construct for authorization domains, and (2) communication primitives for authorizations, which allow to pass around authorizations to act on a given channel. An authorization error then corresponds to an action involving a channel and a role not enclosed by an appropriate authorization scope. We introduce a typing discipline that ensures that processes never reduce to authorization errors, including when parties dynamically acquire authorizations. 相似文献