• Title/Summary/Keyword: SP8T

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3:1 Bandwidth Switch Module by Using GaAs PH Diode (GaAs PIN Diode를 이용한 3:1 대역폭 스위치 모듈)

  • 정명득;이경학;박동철
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.5
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    • pp.451-458
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    • 2002
  • Absorptive type SP3T(Single Pole Three Throw) and SP8T switch modules over the 6-18 GHz are designed and fabricated. The epitaxial structure of GaAs PIN diode for switch modules are designed for low loss and high power capability. The maximum input power of SP3T and SP8T switch modules are 2 W and 1 W, respectively. The switching time with driver circuit is less than 130 nsec. The maximum insertion loss of SP3T switch module and SP8T module shows 2.8 dB and 4.2 dB, respectively. The isolation between input port and output port is more than 55 dB. Two switch modules for electronic warfare system have passed the environment tests of the related test items.

A Single-Pole, Eight-Throw, Radio-Frequency, MicroElectroMechanical Systems Switch for Multi-Band / Multi-Mode Front-End Module

  • Kang, Sung-Chan;Kim, Hyeon-Cheol;Chun, Kuk-Jin
    • Journal of Sensor Science and Technology
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    • v.20 no.2
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    • pp.77-81
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    • 2011
  • This paper presents a single-pole eight-throw(SP8T) switch based on proposed a radio-frequency(RF) microelectromechanical systems (MEMS) switches. The proposed switch was driven by a double stop(DS) comb drive, with a lateral resistive contact. Additionally, the proposed switch was designed to have tapered signal line and bi-directionally actuated. A forward actuation connects between signal lines and contact part, and the output becomes on-state. A reverse actuation connects between ground lines and contact part, and the output becomes off-state. The SP8T switch of 3-stage tree topology was developed based on an arrangement of the proposed RF MEMS switches. The developed SP8T switch had an actuation voltage of 12 V, an insertion loss of 1.3 dB, a return loss of 15.1 dB, and an isolation of 31.4 dB at 6 GHz.

Seasonal Dynamics and Community Structure of Tintinnina in lower Seomjin River System (섬진강 하류계에서 유종섬모충류의 군집구조와 계절적 동태)

  • 유형빈;박수산
    • Korean Journal of Environmental Biology
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    • v.19 no.1
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    • pp.25-36
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    • 2001
  • Precent study has been carried out to clarify the ecological characteristics of Tintinnina community, during the period from March,1998 to January, 1999 at twelve stations in lower Seomjin river system. During the surveyed period, a total of 56 species were identified. Seasonal variation of number of species occurred was varied: 43 species during spring season, 21 species during summer season, 27 species during autumn season, 20 species during winter season. Total abundance of Tintinnina ranged from 0 to 170,134 indiv./㎥. The abundance was high in March and low in September. Among 22 dominant species, 18 species (81.8%) were Tintinnopsis genus. The relationships between environmental factors and Tintinnina community were as follows; 11 species (Tintinnopsis rara, T. angulata, T. sp. 1, T. sp. 4, T. sp. 5, T. sp. 8, T. sp. 9, Stenosemella pacifica, S. steini, Codonellopsis nipponica, Favella taraikaensis) occurred from 10 to 15$^{\circ}C$ and 2 species (Codonella amphorella, Leprotintinnus neriticus) occurred from 5 to 3$0^{\circ}C$. Many species occurred from 10.1 to 25.0$\textperthousand$ of salinity. Four species (Tintinnopsis acuminata, T. angulata, T. sp. 10, T. sp. 11) occurred in freshwater only, while four species (Tintinnopsis rapa, T. baltica, T lata, Codonella sp.) occurred from 0.1 to 31.2$\textperthousand$ of salinity.

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CysLT receptor-mediated NOX2 activation is required for IL-8 production in HMC-1 cells induced by Trichomonas vaginalis-derived secretory products

  • Young Ah Lee;Myeong Heon Shin
    • Parasites, Hosts and Diseases
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    • v.62 no.3
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    • pp.270-280
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    • 2024
  • Trichomoniasis is caused by a sexually transmitted flagellate protozoan parasite Trichomonas vaginalis. T. vaginalis-derived secretory products (TvSP) contain lipid mediators such as leukotriene B4 (LTB4) and various cysteinyl leukotrienes (CysLTs) which included LTC4, LTD4, and LTE4. However, the signaling mechanisms by which T. vaginalis-induced CysLTs stimulate interleukin (IL)-8 production in human mast cells remain unclear. In this study, we investigated these mechanisms in human mast cells (HMC-1). Stimulation with TvSP resulted in increased intracellular reactive oxygen species (ROS) generation and NADPH oxidase 2 (NOX2) activation compared to unstimulated cells. Pre-treatment with NOX2 inhibitors such as diphenyleneiodonium chloride (DPI) or apocynin significantly reduced ROS production in TvSP-stimulated HMC-1 cells. Additionally, TvSP stimulation increased NOX2 protein expression and the translocation of p47phox from the cytosol to the membrane. Pretreatment of HMC-1 cells with PI3K or PKC inhibitors reduced TvSP-induced p47phox translocation and ROS generation. Furthermore, NOX2 inhibitors or NOX2 siRNA prevented CREB phosphorylation and IL-8 gene expression or protein secretion induced by TvSP. Pretreatment with a CysLTR antagonist significantly inhibited TvSP-induced ROS production, CREB phosphorylation, and IL-8 production. These results indicate that CysLT-mediated activation of NOX2 plays a crucial role in ROS-dependent IL-8 production in human mast cells stimulated by T. vaginalis-secreted CysLTs. These findings enhance our understanding of the inflammatory response in trichomoniasis and may inform the development of targeted therapies to mitigate this response.

Structure and Arterial Relaxing Activity of Substance P-related Peptides and Substance P analogs (Substance P-related peptide들과 유도체의 구조 및 혈관이완 활성)

  • KIM Eun Jung;KIM Chan-Hee;GO Hye-Jin;KIM In Hae;AN Sang Hyun;SOHN Hee-Young;PARK Hee Yeon;YOON Ho Dong;CHANG Young-Chae;HONG Yong-Ki;PARK Nam Gyu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.38 no.3
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    • pp.143-147
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    • 2005
  • Relationship between structure and biological activity was performed using the five substance P-related peptides (SPRPs) [mammalian-SP (M-SP), cod-SP (C-SP), trout-SP (T-SP), lungfish-SP (L-SP) and Ranakinin] and four SP analogs [[$His^5$]-SP (5H-SP), [$Gly^5$]-SP (5G-SP), ($Ile^8$)-SP (8I-SP) and ($Trp^8$)-Ranakinin (8W-Ranakinin)]. The circular dichroism (CD) spectra showed that all of the peptides took an unordered structure in buffer solution and artificial liposomes. However, 8W-Ranakinin undergoes conformational changes by being transferred into neutral and acidic liposomes from an unordered structure to more ordered structure. The arterial relaxing effect of the peptides was also studied with guinea-pig aorta (GPA), As a result of the studies, L-SP was about 14-fold more potant than M-SP. The order of potency compared to $EC_{50}$ value was $L-SP{\gg}M-SP>5G-SP{\ge}8I-SP>5H-SP>T-SP$, C-SP, Ranakinin, 8W-Ranakinin.

NF-${\kappa}B$ and CREB Are Involved in IL-8 Production of Human Neutrophils Induced by Trichomonas vaginalis-Derived Secretory Products

  • Nam, Young-Hee;Min, Deul-Le;Park, Soon-Jung;Kim, Kyeong-Ah;Lee, Young-Ah;Shin, Myeong-Heon
    • Parasites, Hosts and Diseases
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    • v.49 no.3
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    • pp.291-294
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    • 2011
  • Trichomonas vaginalis is a flagellated lumen-dwelling extracellular protozoan parasite that causes human trichomoniasis via sexual intercourse. Human neutrophils play a crucial role in acute tissue inflammatory responses in T. vaginalis infection. In this study, we investigated the signaling mechanism of neutrophil responses when stimulated with T. vaginalis-derived secretory products (TvSP), which were collected from $1{\times}10^7$ live trichomonads. Incubation of human neutrophils isolated from peripheral blood with TvSP induced up-regulation of IL-8 protein secretion. In addition, stimulation with TvSP induced phosphorylation of NF-${\kappa}B$ and CREB in neutrophils. Moreover, TvSP-induced IL-8 production was also significantly inhibited by pretreatment of neutrophils with $i{\kappa}B$ inhibitor or CREB inhibitor. These results suggest that transcription factors NF-${\kappa}B$ and CREB are involved in IL-8 production in human neutrophils induced by stimulation with T. vaginalis infection.

Isolation of causative agents from CMT-positive mastitic milk and antimicrobial susceptibility of isolates (CMT 양성 유즙에서 유방염 원인균 분리 및 분리균의 항균제 감수성)

  • 이정원;김추철;윤여백;송희종;최인방
    • Korean Journal of Veterinary Service
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    • v.20 no.2
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    • pp.151-159
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    • 1997
  • This study was carried out to isolate of causative agents from CMT-positive and mean somatic cell count(SCC) $\geq$500,000 cells/ml mastitic milk, and evaluate to antimicrobial susceptibility of isolates in Iksan branch area from January to November, 1996. 1. The CMT-positivity(SCC 500,000 cells/ml) of 610 heads was 36.2% (221), and of 2,373 quarter milks was 16.1% (383). 2. The Gram-positive isolates were 153 strains which was Staphylococcus sp (115), Micrococcus sp (18), Streptococcus sp (10), Listeria monocytogenes (5) and Enterococcus faecalis(5). 3. The Gram-negative isolates were 66 strains including E coli(14), Yersinia sp (13), Shigella sp(8), Enterobacillus sp(8), Cedecea sp(5), Pseudomonas aeruginosa(5), Proteus sp(5), Klebsiella sp(4), Salmonella sp(2), kluyvera ascorbate(1) and Tatumella ptyseos (1). 4. The Gram positive strains of isolates were moderately susceptible to T/s, Cp, Fd, Imp, Aug, Rif, Cft and Va. And the Gram negative strains of Isolates were moderately susceptible to T/s, Cp, Imp, Pi and Ti, In order. 5. Multiple antimicrobial resistant patterns were encountered 62 and 36 from Gram positive and negative isolates, respectively.

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Immunosuppressive Effects of Bryoria sp. (Lichen-Forming Fungus) Extracts via Inhibition of CD8+ T-Cell Proliferation and IL-2 Production in CD4+ T Cells

  • Hwang, Yun-Ho;Lee, Sung-Ju;Kang, Kyung-Yun;Hur, Jae-Seoun;Yee, Sung-Tae
    • Journal of Microbiology and Biotechnology
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    • v.27 no.6
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    • pp.1189-1197
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    • 2017
  • Lichen-forming fungi are known to have various biological activities, such as antioxidant, antimicrobial, antitumor, antiviral, anti-inflammation, and anti proliferative effects. However, the immunosuppressive effects of Bryoria sp. extract (BSE) have not previously been investigated. In this study, the inhibitory activity of BSE on the proliferation of $CD8^+$ T cells and the mixed lymphocytes reaction (MLR) was evaluated in vitro. BSE was non-toxic in spleen cells and suppressed the growth of splenocytes induced by anti-CD3. The suppressed cell population in spleen cells consisted of $CD8^+$ T cells and their proliferation was inhibited by the treatment with BSE. This extract significantly suppressed the IL-2 associated with T cell growth and $IFN-{\gamma}$ as the $CD8^+$ T cell marker. Furthermore, BSE reduced the expression of the IL-2 receptor alpha chain ($IL-2R{\alpha}$) on $CD8^+$ T cells and CD86 on dendritic cells by acting as antigen-presenting cells. Finally, the MLR produced by the co-culture of C57BL/6 and MMC-treated BALB/c was suppressed by BSE. IL-2, $IFN-{\gamma}$, and CD69 on $CD8^+$ T cells in MLR condition were inhibited by BSE. These results indicate that BSE inhibits the MLR via the suppression of $IL-2R{\alpha}$ expression in $CD8^+$ T cells. BSE has the potential to be developed as an anti-immunosuppression agent for organ transplants.

Prevalence of intestinal parasites of pet dogs in Taejon city (대전광역시 애완견의 장내기생충 감염실태조사)

  • 오윤희;송운재;이필돈;박배근
    • Korean Journal of Veterinary Service
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    • v.21 no.4
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    • pp.391-400
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    • 1998
  • In order to survey the prevalence of intestinal parasites in dogs, 304 fecal samples were taken from dogs in Taejon city, The prevalence and identification of intestinal parasites were determined by the fecal examinations using sheather's floating technique and sedimentation methods and then Cryptosporidium oocysts were identified by kinyoun's modified acid fast stainning method. The results were obtained as follows ; 1. Parasite eggs and oocysts were detected in 105 samples (34.5%) from 304 cases of dog feces. 2. The 11 kinds of eggs and oocysts were isolated from the feces of dog. Those were Ancylostoma caninum (12.1%, 37 dogs), Trichuris vulpis (11.5%, 35 dogs), Toxocara canis (10.2%, 31 dogs), Isospora sp (7.2%, 22 dogs), Cryptosporidium sp (3.6%, 11 dogs), Toxascaris leonine (1.9%, 6 dogs), Strongyloides sp (1.9%, 6 dogs), Taenia sp (0.6%, 2 dogs), Diphylidium caninum (0.3%, 1 dog), Spirometra sp (0.3%, 1 dog) and Clonorchis sinensis (0.3%, 1 dog). 3. It was mixed infection such as single, double, triple and quadruple, 64.8%, 25.7%, 8.6% and 0.9%, respectively. 4. In indiviually-raised 4095, the infectious late of T canis (11.4%), A Caninum(13.2%), Cryptosporidium sp (6.1%), T leontna (2.6%) were higher than those of group raised dogs. But the infectious rate of T vulpis (12.1%) in group raised dogs was higher than that of individually-raised dogs. 5. Adults of Demodex and Sarcoptes which have been found in this survey are excluded in this report.

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Production of Hydrogen and Volatile Fatty Acid by Enterobacter sp. T4384 Using Organic Waste Materials

  • Kim, Byung-Chun;Deshpande, Tushar R.;Chun, Jongsik;Yi, Sung Chul;Kim, Hyunook;Um, Youngsoon;Sang, Byoung-In
    • Journal of Microbiology and Biotechnology
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    • v.23 no.2
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    • pp.189-194
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    • 2013
  • In a study of hydrogen-producing bacteria, strain T4384 was isolated from rice field samples in the Republic of Korea. The isolate was identified as Enterobacter sp. T4384 by phylogenetic analysis of 16S rRNA and rpoB gene sequences. Enterobacter sp. T4384 grew at a temperature range of $10-45^{\circ}C$ and at an initial pH range of 4.5-9.5. Strain T4384 produced hydrogen at 0-6% NaCl by using glucose, fructose, and mannose. In serum bottle cultures using a complete medium, Enterobacter sp. T4384 produced 1,098 ml/l $H_2$, 4.0 g/l ethanol, and 1.0 g/l acetic acid. In a pH-regulated jar fermenter culture with the biogas removed, 2,202 ml/l $H_2$, 6.2 g/l ethanol, and 1.0 g/l acetic acid were produced, and the lag-phase time was 4.8 h. Strain T4384 metabolized the hydrolysate of organic waste for the production of hydrogen and volatile fatty acid. The strain T4384 produced 947 ml/l $H_2$, 3.2 g/l ethanol, and 0.2 g/l acetic acid from 6% (w/v) food waste hydrolysate; 738 ml/l $H_2$, 4.2 g/l ethanol, and 0.8 g/l acetic acid from Miscanthus sinensis hydrolysate; and 805 ml/l $H_2$, 5.0 g/l ethanol, and 0.7 g/l acetic acid from Sorghum bicolor hydrolysate.