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951.
Bernadette B. Bagon Ju Kyoung Oh Valerie Diane V. Valeriano Edward Alain B. Pajarillo Dae-Kyung Kang 《Molecules (Basel, Switzerland)》2021,26(18)
Lactobacillus sp. have long been studied for their great potential in probiotic applications. Recently, proteomics analysis has become a useful tool for studies on potential lactobacilli probiotics. Specifically, proteomics has helped determine and describe the physiological changes that lactic acid bacteria undergo in specific conditions, especially in the host gut. In particular, the extracellular proteome, or exoproteome, of lactobacilli contains proteins specific to host– or environment–microbe interactions. Using gel-free, label-free ultra-high performance liquid chromatography tandem mass spectrometry, we explored the exoproteome of the probiotic candidate Lactobacillus mucosae LM1 subjected to bile treatment, to determine the proteins it may use against bile stress in the gut. Bile stress increased the size of the LM1 exoproteome, secreting ribosomal proteins (50S ribosomal protein L27 and L16) and metabolic proteins (lactate dehydrogenase, phosphoglycerate kinase, glyceraldehyde-3-phosphate dehydrogenase and pyruvate dehydrogenases, among others) that might have moonlighting functions in the LM1 bile stress response. Interestingly, membrane-associated proteins (transporters, peptidase, ligase and cell division protein ftsH) were among the key proteins whose secretion were induced by the LM1 bile stress response. These specific proteins from LM1 exoproteome will be useful in observing the proposed bile response mechanisms via in vitro experiments. Our data also reveal the possible beneficial effects of LM1 to the host gut. 相似文献
952.
Lee Soon Seok Lee Jeong Gyu Oh Chang Hwan Kim Young Boo Kim Young Sun 《Telecommunication Systems》2000,14(1-4):269-290
In this paper, we present the basic idea and some concepts for the architecture of the ATM switching system being developed
in ETRI of KOREA, and also describe its performance. RSE (Reference Service Entity) concept is introduced to define the characteristics
of user’s traffic. This concept is useful to represent the demand of CPE (Customer Premise Equipment) user sets and one of
point‐to‐multipoint connections. We also propose RUCA (Reference Units for Connection Attempts) concept with which we can
illustrate the call/connection level performance of the ATM switching system. This concept can be applied for measuring the
call processing capability in both point‐to‐multipoint connections and multipoint‐to‐multipoint connections when call set‐up
between users is performed by a sequence of point‐to‐point connections basis. From the basic concepts and the recommendations
of ITU‐T, the design objective of the system performance is specified. We represent the methodologies for dimensioning the
system to achieve the design objectives, and estimate the system performances. Then we show that our developing system has
suitable performance to accommodate the future B‐ISDN.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
953.
Kim J.M. Oh K. Park T.S. Kim C.S. Jeong K. 《Photonics Technology Letters, IEEE》2000,12(11):1504-1506
A new method to suppress the cladding-mode coupling loss in fiber Bragg gratings, by independent control of the core refractive index profile and the photosensitive profile, is proposed and experimentally demonstrated. Across the core and the inner cladding, a uniform step photosensitive profile was introduced by co-doping GeO/sub 2/ and B/sub 2/O/sub 3/. The core refractive index was selectively raised by further doping Al/sub 2/O/sub 3/ in the core that has negligible photosensitivity at 244 nm. For strong Bragg gratings inscribed on the fiber, the cladding-mode coupling loss was suppressed below 0.3 dB. 相似文献
954.
In-Joong Ha Sang-Hoon Lee 《Industrial Electronics, IEEE Transactions on》2000,47(4):842-853
This paper describes an effective online method for identifying both stator and rotor resistances, which is useful in robust speed control of induction motors without rotational transducers. The identification method for stator resistance is derived from the steady-state equations of induction motor dynamics. On the other hand, the identification method for rotor resistance is based on the linearly perturbed equations of induction motor dynamics about the operating point. The identification method for both stator and rotor resistances uses only the information of stator currents and voltages. It can provide fairly good identification accuracy regardless of load conditions and be easily incorporated into any sensorless speed controller proposed in the prior literature. Some experimental results are presented to demonstrate the practical use of the identification method. A sensorless speed control system has been built for experimental work, in which all algorithms for identification and control are implemented on a digital signal processor. The experimental results confirm that the proposed method allows for high-precision speed control of commercially available induction motors without rotational transducers 相似文献
955.
High frequency/high dynamic range CMOS VGA 总被引:3,自引:0,他引:3
A novel CMOS variable gain amplifier (VGA) with high frequency and high dynamic range is proposed. The VGA has a controllable gain range of -50 dB-+50 dB which can be controlled by adjusting the external voltage as well as an enhanced operating frequency range up to 200 MHz. It is fabricated using 0.35 μm CMOS technology and has a core area of 580×660 μm 相似文献
956.
Jong-Wook Lee Hyung-Ki Kim Woo-Han Lee Min-Rok Oh Yo-Hwan Koh 《Electron Devices, IEEE Transactions on》2000,47(5):1013-1017
Hot-carrier degradation behavior of thin-film SOI (silicon-on-insulator) nMOSFETs with various isolation techniques and buried oxide (BOX) thickness has been investigated focused on the stress behavior in the SOI structure. LOCOS (local oxidation of silicon) and STI (shallow trench isolation) processes are used as isolation techniques. Buried oxide thickness is 100 and 400 nm, respectively. From the isolation point of view, STI-processed SOI devices have better hot-carrier immunity than LOCOS-isolated SOI devices. In terms of BOX thickness, the thick BOX case has better hot-carrier degradation characteristics than the thin one. It is found that STI process and thick BOX cases induce smaller stress than LOCOS process and thin BOX cases, resulting in better hot-carrier immunity 相似文献
957.
Jong-Wook Kim Jae-Eung Oh Seong-Chul Hong Chung-Hoon Park Tae-Kyung Yoo 《Electron Device Letters, IEEE》2000,21(7):329-331
Room temperature operation of far-infrared detectors made of self-assembled quantum dots embedded in the channel region of modulation-doped heterostructures is demonstrated. At room temperature, the detector shows a low dark current ranging in the nano-amperes at a bias voltage of 10 V. After the optimization of the separation between the quantum dot region and the 2DEG, a peak responsivity of 5.3 A/W is obtained at 9.0 μm. The high detectivities of 6×108 and 5×1010 cmHz1/2/W are obtained at room temperature and 80 K, respectively 相似文献
958.
959.
Sung-Tag Oh Wonsuk Lee Si Young Chang Myung-Jin Suk 《Research on Chemical Intermediates》2014,40(7):2495-2500
Porous Cu–Sn with controlled pore characteristics was synthesized by a freeze-drying and sintering process. CuO and SnO2 powders were selected as the source material, which are hydrogen-reduced to metallic Cu–Sn in the sintering stage. Camphene-based CuO–SnO2 slurries were prepared by milling at 60 °C with a small amount of dispersant. Freezing of a slurry was done at ?40 °C with unidirectional control of the growth direction of the camphene. Pores were generated by sublimation of the camphene. The green bodies were sintered at 650 °C under a hydrogen atmosphere. The sintered bodies with Cu3Sn, Cu6Sn5 and β-Sn phases showed macroscopic aligned pores with an average size of 200 μm. The internal wall of the macroscopic pores is also porous, and there are a number of many small pores in it. The formation of macroscopic and microscopic pores was discussed in terms of solidification behavior of the liquid with foreign particles. 相似文献
960.
Beyond the simple keyword matching methods in contextual advertising, we propose a rich contextual matching (CM) model adopting a classification method for topic targeting and a query expansion method for semantic ad matching. This letter reports on an investigation into the empirical effects of the CM model by comparing the click‐through rates (CTRs) of two practical online news advertising systems. Based on the evaluation results from over 100 million impressions, we prove that the average CTR of our proposed model outperforms that of a traditional model. 相似文献