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In vivo Kinetic Biodistribution of Nano‐Sized Outer Membrane Vesicles Derived from Bacteria 下载免费PDF全文
Su Chul Jang Sae Rom Kim Yae Jin Yoon Kyong‐Su Park Ji Hyun Kim Jaewook Lee Oh Youn Kim Eun‐Jeong Choi Dae‐Kyum Kim Dong‐Sic Choi Yoon‐Keun Kim Jaesung Park Dolores Di Vizio Yong Song Gho 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(4):456-461
Evaluation of kinetic distribution and behaviors of nanoparticles in vivo provides crucial clues into their roles in living organisms. Extracellular vesicles are evolutionary conserved nanoparticles, known to play important biological functions in intercellular, inter‐species, and inter‐kingdom communication. In this study, the first kinetic analysis of the biodistribution of outer membrane vesicles (OMVs)—bacterial extracellular vesicles—with immune‐modulatory functions is performed. OMVs, injected intraperitoneally, spread to the whole mouse body and accumulate in the liver, lung, spleen, and kidney within 3 h of administration. As an early systemic inflammation response, increased levels of TNF‐α and IL‐6 are observed in serum and bronchoalveolar lavage fluid. In addition, the number of leukocytes and platelets in the blood is decreased. OMVs and cytokine concentrations, as well as body temperature are gradually decreased 6 h after OMV injection, in concomitance with the formation of eye exudates, and of an increase in ICAM‐1 levels in the lung. Following OMV elimination, most of the inflammatory signs are reverted, 12 h post‐injection. However, leukocytes in bronchoalveolar lavage fluid are increased as a late reaction. Taken together, these results suggest that OMVs are effective mediators of long distance communication in vivo. 相似文献
3.
Because biological wastewater treatment plants (WWTPs) involve a long time-delay and various disturbances, in general, skilled operators manually control the plant based on empirical knowledge. And operators usually diagnose the plant using similar cases experienced in the past. For the effective management of the plant, system automation has to be accomplished based upon operating recipes. This paper introduces automatic control and diagnosis based upon the operator's knowledge. Fuzzy logic was employed to design this knowledge-based controller because fuzzy logic can convert the linguistic information to rules. The controller can manage the influent and external carbon in considering the loading rate. The input of the controller is not the loading rate but the dissolved oxygen (DO) lag-time, which has a strong relation to the loading rate. This approach can replace an expensive sensor, which measures the loading rate and ammonia concentration in the reactor, with a cheaper DO sensor. The proposed controller can assure optimal operation and prevent the over-feeding problem. Case-based diagnosis was achieved by the analysis of profile patterns collected from the past. A new test profile was diagnosed by comparing it with template patterns containing normal and abnormal cases. The proposed control and diagnostic system will guarantee the effective and stable operation of WWTPs. 相似文献
4.
Seo K. Heiblum M. Knoedler C.M. Oh J.E. Pamulapati J. Bhattacharya P. 《Electron Device Letters, IEEE》1989,10(2):73-75
A high-gain ballistic hot-electron device is described. The GaAs-AlGaAs heterostructure device, with a 21-mm-thick pseudomorphic In 0.12Ga0.88As base, had a current gain of 27 at 77 K and 41 at 4.2 K. As characteristically seen in ballistic devices, transfer into the L valley limited the maximum gain. The Γ-L valley separation in the strained In0.12Ga0.88As was estimated to be about 380 meV 相似文献
5.
A W-band divide-by-3 frequency divider with wide bandwidth and low power dissipation is presented using harmonic injection-locking technique. A cascode FET is employed for a self-oscillating second-harmonic mixer which is injection-locked by third-harmonic input to obtain the division order of three. The fabricated frequency divider using 0.1 /spl mu/m GaAs metamorphic HEMT technology shows superior performance such as large bandwidth of 6.1 GHz around 83.1 GHz (7.3%) under small DC power consumption of 12 mW. 相似文献
6.
Yong Bae Park Keum Cheol Hwang Ikmo Park 《Microwave and Wireless Components Letters, IEEE》2008,18(3):152-154
A tapered coaxial tip in a parallel plate waveguide is investigated. A boundary-value problem of electromagnetic scattering from a tapered coaxial monopole is solved rigorously based on the Fourier transform, eigenfunction expansion, and mode matching. Scattering parameters are represented in a series and computed to understand the behavior of the scattering in terms of the coaxial tip geometry. 相似文献
7.
Youngjoong Ko Sooyong Park Jungyun Seo Soonhwang Choi 《Information and Software Technology》2007,49(11-12):1128-1140
In order to efficiently develop large-scale and complicated software, it is important for system engineers to correctly understand users’ requirements. Most requirements in large-scale projects are collected from various stakeholders located in various regions, and they are generally written in natural language. Therefore, the initial collected requirements must be classified into various topics prior to analysis phases in order to be usable as input in several requirements analysis methods. If this classification process is manually done by analysts, it becomes a time-consuming task. To solve this problem, we propose a new bootstrapping method which can automatically classify requirements sentences into each topic category using only topic words as the representative of the analysts’ views. The proposed method is verified through experiments using two requirements data sets: one written in English and the other in Korean. The significant performances were achieved in the experiments: the 84.28 and 87.91 F1 scores for the English and Korean data sets, respectively. As a result, the proposed method can provide an effective function for an Internet-based requirements analysis-supporting system so as to efficiently gather and analyze requirements from various and distributed stakeholders by using the Internet. 相似文献
8.
To help in clarifying the relationship between the time lag and attenuation of nitrogen (N) loads generated in agricultural catchments, long-term trends in activities that generate N loads and in environmental N loads were estimated in catchments in Japan and Korea dominated by non-point-source emissions. Our approach used statistical data and geographical information system software to analyze pollutant loads. The method was successful in both countries because of the availability of well-developed statistics, geographical information, and weather and water quality monitoring systems, and the accumulation of research data concerning the generation of N loads and the fate of N in soils. Comparison of environmental loads with the loads observed in river water at the outlet of each catchment revealed that: (1) the effect of changes in the environmental load in a catchment appeared almost immediately in the river water quality in Korea, but did not appear clearly even 10 years later in Japan; and (2) the strength of the attenuation appeared to be much lower in Korea than in Japan. These findings suggest that regional characteristics play important roles in the sensitivity of water quality to load-generating activities. 相似文献
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We study a practical approach to match the performance of an output-queued switch statistically. For this purpose, we propose a novel switching architecture called a multiple input/output-queued (MIOQ) switch that requires no speedup for providing sufficient switching bandwidth. To operate an MIOQ switch in a practical manner, we also propose a multitoken-based arbiter which schedules the switch at a high operation rate and a virtual first-in first-out queueing scheme which guarantees the departure order of cells belonging to the same traffic flow at output. Additionally, we show that the proposed switch can naturally provide asymmetric bandwidth for inputs and outputs, which may be important in dealing with the links with different bandwidth demands. Finally, we compare the performance of an MIOQ switch with that of an output-queued switch and discuss the design criteria to match the performance of an output-queued switch. 相似文献