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991.
Although ultrasound-based drug delivery has only seen limited clinical use for transdermal drug delivery, there has been considerable momentum in research aimed at using ultrasound for a wide variety of medical applications. Ultrasound-mediated gene therapy using sonoporation and targeted delivery has progressed from in vitro proof-of-concept studies to produce biological effects in angiogenesis and diabetes studies. These techniques have also been used for cancer therapy, thrombolysis, and disruption of the blood-brain barrier in animal models. It is also worth noting that ultrasound can facilitate targeted drug delivery through thermal means, in addition to the mechanisms associated with cavitation. Ultrasound hyperthermia can be used to target thermally sensitive drug-carrying liposomes or to induce gene expression through localized heat shock response. 相似文献
992.
993.
How does one repeatedly choose actions so as to be fairest to the multiple beneficiaries of those actions? We examine approaches to discovering sequences of actions for which the worst-off beneficiaries are treated maximally well, then secondarily the second-worst-off, and so on. We formulate the problem for the situation where the sequence of action choices continues forever; this problem may be reduced to a set of linear programs. We then extend the problem to situations where the game ends at some unknown finite time in the future. We demonstrate that an optimal solution is intractable, and present two good approximation algorithms. 相似文献
994.
Moatasim Attaelmanan Cheng Pei Feng Al-Hadidy AI 《Construction and Building Materials》2011,25(5):2764-2770
This paper investigates the viability of using high density polyethylene (HDPE) as a modifier for asphalt paving materials. Different ratios of HDPE by weight of asphalt were blended with 80/100 paving grade asphalt. Unmodified and modified asphalt binders were subjected to physicochemical and homogeneity tests. The performance tests including, Marshall Stability, Marshall Quotient (MQ), tensile strength, tensile strength ratio, flexural strength and resilient modulus were carried out on unmodified and modified hot asphalt mixtures. The analyses of test results show that the performance of HDPE-modified asphalt mixtures are better than conventional mixtures. The moisture susceptibility and temperature susceptibility can be reduced by the inclusion of HDPE in the asphalt mixture. A HDPE content of 5% by weight of asphalt is recommended for the improvement of the performance of asphalt concrete mixtures similar to that investigated in this study. 相似文献
995.
This paper proposes a case-based reasoning (CBR) approach to construction hazard identification that facilitates systematic feedback of past knowledge in the form of incident cases and hazard identification. This paper focuses on two of the key components of the CBR approach: (1) a detailed knowledge representation scheme, developed based on the modified loss causation model, to codify incident cases and past hazard identification and (2) an intelligent retrieval mechanism that can automatically retrieve relevant past cases. The detailed knowledge representation scheme presented herein is designed to model both incident cases and hazard identification so that both types of knowledge repository can be retrieved simultaneously and adapted for use. The scheme also includes a linguistic structure used to facilitate indexing of cases. The retrieval mechanism is based on the concept of similarity scoring. In this paper, a novel scoring technique based on semantic networks is presented. A case study is presented to demonstrate and validate the proposed approach. 相似文献
996.
Cyclotrimethylenetrinitramine (RDX) is a nitroamine explosive widely used in military applications because of its good explosive and safety properties. Using bacterial cellulose (BC) gelatin with a three-dimensional network as a carrier and sodium dodecyl benzene sulfonate (SDBS) and p-octyl polyethylene glycol phenylether (OP) as surfactants, nanoscale RDX films were prepared by a solvent/nonsolvent method. It was found that the granularity distribution of RDX in the films in the presence of SDBS and OP in the RDX solution was very uniform compared to the granularity distribution in the absence of surfactant. The surfactants also improved the dispersion of RDX in the film and the adhesion of RDX onto the network of BC gelatin, leading to an increase of RDX content in the film. Corresponding contents of RDX in the presence of SDBS and OP are 82.59 and 84.47% in the films, respectively, increasing RDX content by 7.23 and 9.11% over the films without surfactants. 相似文献
997.
Qian‐Yu Kuok Chen‐Yu Yeh Bor‐Chyuan Su Pei‐Ling Hsu Hao Ni Ming‐Yie Liu Fan‐E Mo 《Molecular nutrition & food research》2013,57(10):1892-1896
Ganoderma mushrooms (Lingzhi in Chinese) have well‐documented health benefits. Ganoderma tsugae (G. tsugae), one of the ganoderma species, has been commercially cultivated as a dietary supplement. Because G. tsugae has high antioxidant activity and because oxidative stress is often associated with cardiac injury, we hypothesized that G. tsugae protects against cardiac injury by alleviating oxidative stress. We tested the hypothesis using a work‐overload‐induced myocardial injury model created by challenging mice with isoproterenol (ISO). Remarkably, oral G. tsugae protected the mice from ISO‐induced myocardial injury. Moreover, the triterpenoid fraction of G. tsugae, composed of a mixture of nine structurally related ganoderic acids (GAs), provided cardioprotection by inhibiting the ISO‐induced expression of Fas/Fas ligand, oxidative stress, and apoptosis. The antioxidant activity of GAs was tested in cultured cardio‐myoblast H9c2 cells against the insult of H2O2. GAs dissipated the cellular reactive oxygen species imposed by H2O2 and prevented cell death. Our findings uncovered the cardioprotective activity of G. tsugae and identified GAs as the bioactive components against cardiac insults. 相似文献
998.
With increases in storm frequency and intensity, municipalities are finding new ways of managing stormwater. Solutions require collaboration across planning disciplines and input from an informed public. This study compares a system of bioswales to existing curb and gutter infrastructure in a post-industrial streetscape of Hamilton, Ontario. Using the geodesign process, a section of Ottawa St. North was modelled to show how green infrastructure can ease the burden on aging, combined sewer systems. Qualitative data was gathered from residents of the neighbourhood through field notes, and quantitative geospatial data through GIS. Parametric modelling was used to generate a design, and scenarios created to show resulting impacts on stormwater run-off. The model was posted online as an interactive presentation, accessible to all stakeholders for review and comment. The results of the study demonstrate powerful new tools that can assist landscape architects in designing, collaborating and communicating stormwater strategies. 相似文献
999.
Ro Ruyen Yuan-Feng Chiang Chia-Chi Sung Lee Ruyue Wu Sean 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2010,57(1):46-51
In this study, the finite element method is employed to calculate SAW characteristics in (100) AlN/diamond based structures with different electrical interfaces; i.e., IDT/ AlN/diamond, AlN/IDT/diamond, IDT/AlN/thin metal film/ diamond, and thin metal film/AlN/IDT/diamond. The effects of Cu and Al electrodes as well as the thickness of electrode on phase velocity, coupling coefficient, and reflectivity of SAWs are illustrated. Propagation characteristics of SAWs in (002) AlN/diamond-based structures are also presented for comparison. Simulation results show that to retain a large reflectivity for the design of RF filters and duplexers, the Cu IDT/(100) AlN/diamond structure possesses the highest phase velocity and largest coupling coefficient at the smallest AlN film thickness- to-wavelength ratio. 相似文献
1000.
天津钢管公司炼钢厂在设计期间,为连铸设备设计了一套连铸坯计算机质量跟踪系统,该系统能够在线监控连铸坯的质量状况,用于指导生产和检验。本文详细介绍了此系统的各项功能及其使用方法,阐述了恢复使用此项功能所要解决的问题,以及给公司所带来的利益。 相似文献