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排序方式: 共有1117条查询结果,搜索用时 984 毫秒
991.
Yuan Xiong Lang Chen Pei Liu Tao Yu Chuanchuan Lin Chenchen Yan Yiqiang Hu Wu Zhou Yun Sun Adriana C. Panayi Faqi Cao Hang Xue Liangcong Hu Ze Lin Xudong Xie Xiufeng Xiao Qian Feng Bobin Mi Guohui Liu 《Small (Weinheim an der Bergstrasse, Germany)》2022,18(1):2104229
The treatment of diabetic wounds remains a major challenge in clinical practice, with chronic wounds characterized by multiple drug-resistant bacterial infections, angiopathy, and oxidative damage to the microenvironment. Herein, a novel in situ injectable HA@MnO2/FGF-2/Exos hydrogel is introduced for improving diabetic wound healing. Through a simple local injection, this hydrogel is able to form a protective barrier covering the wound, providing rapid hemostasis and long-term antibacterial protection. The MnO2/ε-PL nanosheet is able to catalyze the excess H2O2 produced in the wound, converting it to O2, thus not only eliminating the harmful effects of H2O2 but also providing O2 for wound healing. Moreover, the release of M2-derived Exosomes (M2 Exos) and FGF-2 growth factor stimulates angiogenesis and epithelization, respectively. These in vivo and in vitro results demonstrate accelerated healing of diabetic wounds with the use of the HA@MnO2/FGF-2/Exos hydrogel, presenting a viable strategy for chronic diabetic wound repair. 相似文献
992.
Joshua Finnis Nalin Saigal Adriana Iamnitchi Jay Ligatti 《Pervasive and Mobile Computing》2012,8(3):402-414
The dramatic rise in mobile applications has greatly increased threats to the security and privacy of users. Security mechanisms on mobile devices are currently limited, so users need more expressive ways to ensure that downloaded mobile applications do not act maliciously. Policy-specification languages were created for this purpose; they allow the enforcement of user-defined policies on third-party applications. We have implemented LoPSiL, a location-based policy-specification language for mobile devices. This article describes LoPSiL’s design and implementation, several example policies, and experiments that demonstrate LoPSiL’s viability for enforcing policies on mobile devices. 相似文献
993.
The Globus Replica Location Service: Design and Experience 总被引:1,自引:0,他引:1
Chervenak Ann L. Schuler Robert Ripeanu Matei Amer Muhammad Ali Bharathi Shishir Foster Ian Iamnitchi Adriana Kesselman Carl 《Parallel and Distributed Systems, IEEE Transactions on》2009,20(9):1260-1272
Distributed computing systems employ replication to improve overall system robustness, scalability, and performance. A Replica Location Service (RLS) offers a mechanism to maintain and provide information about physical locations of replicas. This paper defines a design framework for RLSs that supports a variety of deployment options. We describe the RLS implementation that is distributed with the Globus Toolkit and is in production use in several Grid deployments. Features of our modular implementation include the use of soft-state protocols to populate a distributed index and Bloom filter compression to reduce overheads for distribution of index information. Our performance evaluation demonstrates that the RLS implementation scales well for individual servers with millions of entries and up to 100 clients. We describe the characteristics of existing RLS deployments and discuss how RLS has been integrated with higher-level data management services. 相似文献
994.
Estefania?Argente Vicente?Botti Carlos?Carrascosa Adriana?Giret Vicente?JulianEmail author Miguel?Rebollo 《Knowledge and Information Systems》2011,29(2):379-403
Today, the need for architectures and computational models for large-scale open multi-agent systems is considered to be a
key issue for the success of agent technology in real-world scenarios. This paper analyzes the significant unsolved problems
that must be taken into account in order to develop real, open multi-agent systems. It identifies requirements and related
open issues, discusses how some of these requirements have been tackled by current technologies, and explains how the THOMAS
architecture is able to give support to these open issues. This paper also describes the THOMAS abstract architecture and
computational model for large-scale open multi-agent systems based on a service-oriented approach that specifically addresses
the design of virtual organizations. An application example for the management of a travel agency system, which demonstrates
the new features of the proposal, is also presented. 相似文献
995.
996.
Adriana S. Ribeiro Lívia M.O. Ribeiro Stela M.M. Leite Jos G. da Silva Jr. Joo C. Ramos Marcelo Navarro Josealdo Tonholo 《Polymer》2006,47(26):8430-8435
Films of poly[(R)-(−)-2-(3′-thienyl)ethyl-(3′,5″-dinitrobenzoyl)-α-phenylglycinate] were deposited on ITO electrodes by potentiodynamic, potentiostatic and galvanostatic methods using a (C4H9)4NBF4/CH3CN electrolyte system containing 20% boron trifluoride diethyl etherate. Polymerisation occurred as a charge dependent process at a potential of 1.4 V vs. Ag/Ag+(CH3CN). The surface morphologies of the films so-formed were examined using atomic force microscopy. The film deposited by the galvanostatic method displayed more homogeneous grain geometry and a larger superficial area than those formed by the other methods. Cyclic voltammetry revealed a well defined redox couple at the anodic region, attributable to polymer p-doping, and a poorly defined redox pair at the cathodic region, attributable to the reduction of the nitro group. The polymeric films obtained were yellow in colour (λmax 425 nm) in the reduced state and light blue (λmax 745 nm) in the oxidised state. 相似文献
997.
Poly[(R)-(-)-3-(1-pyrrolyl)propyl-N-(3,5-dinitrobenzoyl)-α-phenylglycinate] films of various thicknesses were galvanostatically deposited on ITO/glass electrodes using different deposition charges (Qdep), and their electrochromic properties were investigated. Depending on the Qdep employed, the polymeric films presented green-yellow or green-brown colours in the reduced state (λmax at 350 nm and shoulder at 390 nm) and a blue-grey colour in the oxidised state (λmax at 460 nm) with high absorption in the near infrared region (λmax > 800 nm). Whilst films deposited with a Qdep of 40 mC cm−2 presented the highest chromatic contrast (20%), films with a Qdep of 50 mC cm−2 exhibited greater stability to redox cycling (ca. 350 cycles), high coulombic efficiency (>73%) and good optical memory in the reduced state (E = 0.0 V). 相似文献
998.
This work is aimed at finding conditions under which synthetic compartments used as cell models can fuse with each other and allow reagents contained in the different compartments to react. This goal seems to be best achieved by the use of water in oil emulsions (w/o) with dimensions in the range of 30-60 microm. In particular, cell-free EGFP (enhanced green fluorescent protein) synthesis takes place in Tween 80/Span 80 w/o emulsions, and the extent of the reaction can be monitored directly by fluorescence. The medium is mineral oil, containing 0.5 % v/v aqueous solution. Different premixing configurations of the components (plasmid, amino acids, E. Coli extract) are used and compared. The in vitro synthesis of EGFP in emulsion droplets proceeds for 1 h, and the yield is 7.5 ng microL(-1) protein. EGFP synthesis in aqueous solution takes place for at least 5 h. The yield is 10.5 ng microL(-1) protein after 1 h and 15.8 ng microL(-1) protein after 5 h. The results with the w/o emulsions show that solubilisate exchange takes place among the different water droplets, but it is not possible to demonstrate clearly that a true fusion takes place. 相似文献
999.
Adriana V. Ordó?ez Oliveros Aminah Robinson Fayek 《Canadian Metallurgical Quarterly》2005,131(1):42-51
This paper presents a fuzzy logic model that integrates daily site reporting of activity progress and delays, with a schedule updating and forecasting system for construction project monitoring and control. The model developed assists in the analysis of the effects of delays on a project’s completion date and consists of several components: An as-built database integrated with project scheduling; a list of potential causes for delays; a procedure to categorize delays; a method of estimating delay durations utilizing fuzzy logic; a procedure that updates the schedule; and, a procedure that evaluates the effects and likely consequences of delays on activity progress. This model is of relevance to researchers since it makes a contribution in project scheduling by developing a complete approach for handling the uncertainty inherent in schedule updating and activity delay analysis. It also advances the application of fuzzy logic in construction. It is of relevance to construction industry practitioners since it provides them with a useful technique for incorporating as-built data into the schedule, assessing the impact of delays on the schedule, and updating the schedule to reflect the consequences of delays and corrective actions taken. The use of fuzzy logic in the model allows linguistic and subjective assessments to be made, and thereby suits the actual practices commonly used in industry. 相似文献
1000.
André V. Moreira Joaquim Tinoco Joel R. M. Oliveira Adriana Santos 《International Journal of Pavement Engineering》2018,19(10):937-948
One of the main awareness for a road infrastructures manager is to increase its efficiency under limited resources. Pavement Management Systems aim, at last, to support road administrations in the decision-making process regarding its management policy and long-term strategies for maintenance and rehabilitation activities. While several road administrations are putting efforts in developing optimisation methodologies to enhance their decision making process, many still lack of data that allows the development of reliable prediction models for pavement performance. This is a key aspect to develop and test decision-making methodologies. Although there are several prediction models available in the literature, their practical applications are often limited to the very specific network from which data were retrieved at first and to a specific performance indicator (PI). This paper presents a practical application of a Markov model to predict the evolution of five PIs – cracking, skid resistance, bearing capacity, longitudinal evenness and transverse evenness – and consequent combined PIs, using historical data from an extensive pavement database. The conversion for PIs is made through a standardisation procedure proposed by an European COST Action, which may be considered a reference classification system for road administrations. The presented model is intended to be an useful input for researchers and administrations willing to develop and test different optimisation approaches. 相似文献