• Title/Summary/Keyword: step response

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Butyrate and taurine exert a mitigating effect on the inflamed distal intestine of European sea bass fed with a high percentage of soybean meal

  • Rimoldi, Simona;Finzi, Giovanna;Ceccotti, Chiara;Girardello, Rossana;Grimaldi, Annalisa;Ascione, Chiara;Terova, Genciana
    • Fisheries and Aquatic Sciences
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    • v.19 no.10
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    • pp.40.1-40.14
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    • 2016
  • Background: Due to the paucity of oceanic resources utilized in the preparation of diets for cultured fish, commercial feed producers have been trying to replace fishmeal (FM) using alternative protein sources such as vegetable protein meals (VMs). One of the main drawbacks of using VMs in fish feed is related to the presence of a variety of anti-nutritional factors, which could trigger an inflammation process in the distal intestine. This reduces the capacity of the enterocytes to absorb nutrients leading to reduced fish growth performances. Methods: We evaluated the mitigating effects of butyrate and taurine used as feed additives on the morphological abnormalities caused by a soybean meal (SBM)-based diet in the distal intestine of sea bass (Dicentrarchus labrax). We used three experimental diets, containing the same low percentage of FM and high percentage of SBM; two diets were supplemented with either 0.2% sodium butyrate or taurine. Histological changes in the intestine of fish were determined by light and transmission electron microscopy. Infiltration of $CD45^+$ leucocytes in the lamina propria and in the submucosa was assessed by immunohistochemistry. We also quantified by One-Step Taqman$^{(R)}$ real-time RT-PCR the messenger RNA (mRNA) abundance of a panel of genes involved in the intestinal mucosa inflammatory response such as $TNF{\alpha}$ (tumor necrosis factor alpha) and interleukins: IL-8, IL-$1{\beta}$, IL-10, and IL-6. Results: Fish that received for 2 months the diet with 30% soy protein (16.7% SBM and 12.8% full-fat soy) developed an inflammation in the distal intestine, as confirmed by histological and immunohistochemistry data. The expression of target genes in the intestine was deeply influenced by the type of fish diet. Fish fed with taurine-supplemented diet displayed the lowest number of mRNA copies of IL-$1{\beta}$, IL-8, and IL-10 genes in comparison to fish fed with control or butyrate-supplemented diets. Dietary butyrate caused an upregulation of the $TNF{\alpha}$ gene transcription. Among the quantified interleukins, IL-6 was the only one to be not influenced by the diet. Conclusions: Histological and gene expression data suggest that butyrate and taurine could have a role in normalizing the intestinal abnormalities caused by the SBM, but the underling mechanisms of action seem different.

Study on Health Risk Assessment of Carcinogenic Chemicals in Drinking Water (음용수 중 유해 화학 물질에 대한 위해성 평가에 관한 연구 - I. 발암성 화학 물질을 중심으로 -)

  • Chung, Yong;Shin, Dong-Chun;Kim, Jong-Man;Park, Seong-Eun;Yang, Ji-Yeon;Lee, Ja-Koung;Hwang, Man-Sik;Park, Yeon-Shin
    • Environmental Analysis Health and Toxicology
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    • v.10 no.1_2
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    • pp.1-14
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    • 1995
  • The purpose of this research is to assess the health risk of pollutants in drinking water and recommend the guidelines and management plans for maintaining good quality of drinking water. This study has been funded as a national project for three years from 1992 to 1995. This study(the second year, 1993-1994) was conducted to monitor 32 species of carcinogenic chemicals such as volatile organic compounds(VOCs), polynuclear aromatic hydrocarbons(PAHs), pesticides and heavy metals of drinking water at some area in six cities of Korea, and evaluate health risk due to these chemicals through four main steps of risk assessment in drinking water. In hazard identification, 32 species of carcinogenic chemicals were identified by the US EPA classification system. In the step of exposure assessment, sampling of raw, treated and tap water from the public water supply system had been conducted from 1993 to 1994, and 32 chemicals were analyzed. In dose-response assessment, cancer potencies, unit risk estimates and virtually safe doses of carcinogens were obtained by TOX-RISK (Version 3.1). In risk characterization of detected chemicals, health risk due to carcinogens such as vinyl chloride, carbon tetrachloride, dichloromethane, 1, 2-dichloromethane, chloroform, benzene and arsenic of tap water in several cities exceeded 10$^{-5}$ level. We suggest that non-regulated chemicals which exceed 10$^{-5}$ excess cancer risk level, such as vinyl chloride, carbon tetrachloride and 1, 2-dichloroethane, should be monitored periodically and be regulated by the Drinking Water Management Act, and database for exposure parameter of our own situation should be established.

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Desmutagenic Effect of Water Extract from Cassia tora L. on the Mutagenicity of N-methyl-N-nitro-N'-nitrosoguanidinein in E. coli PQ37 (N-methyl-N-nitro-N'-nitrosoguanidine의 변이원성에 대한 결명자 물 추출물의 항돌연변이 효과)

  • Ahn, Byung-Yong
    • Journal of Food Hygiene and Safety
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    • v.24 no.1
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    • pp.46-49
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    • 2009
  • The desmutagenic activity of the water extract of Cassia tara L on the mutagenicity induced by 4-nitroquinoline 1-oxide (4-NQO) and N-methyl-N-nitro-N'-nitrosoguani-dine (MNNG) was studied using the SOS Chromotest with Escherichia coli PQ37. The inhibition rates of water extract of Cassia tara L. at concentration of $100{\mu}g$/assay were 27.5% and 40% against 4-NQO and MNNG. The water extract of Cassia tara L. was separated into methanol soluble and methanol insoluble parts. The methanol soluble part exhibited higher inhibition effects than the methanol insoluble part against the mutagenic activities of 4-NQO and MNNG. Step-wise fractionation of methanol soluble part was done to obtain methanol, ethyl acetate and water fractions. Among these fractions, water fraction had the strongest inhibitory effects of 23.0 and 19.0% against mutagenicities of MNNG and 4NQO, respectively. The results clearly indicated that the water fraction showed much stronger antimutagenicity against MNNG than 4NQO. The inhibition rates of aqueous fraction of methanol-soluble from water extracted Cassia tara L. at concentrations of 1.0, 10, 100 and $250{\mu}g$/assay were 8.0%, 12.0%, 25.5% and 43.0%, respectively. The water fraction showed the inhibitory effects with dose response against the mutagenic activities induced by MNNG.

Development of Image-map Generation and Visualization System Based on UAV for Real-time Disaster Monitoring (실시간 재난 모니터링을 위한 무인항공기 기반 지도생성 및 가시화 시스템 구축)

  • Cheon, Jangwoo;Choi, Kyoungah;Lee, Impyeong
    • Korean Journal of Remote Sensing
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    • v.34 no.2_2
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    • pp.407-418
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    • 2018
  • The frequency and risk of disasters are increasing due to environmental and social factors. In order to respond effectively to disasters that occur unexpectedly, it is very important to quickly obtain up-to-date information about target area. It is possible to intuitively judge the situation about the area through the image-map generated at high speed, so that it can cope with disaster quickly and effectively. In this study, we propose an image-map generation and visualization system from UAV images for real-time disaster monitoring. The proposed system consists of aerial segment and ground segment. In the aerial segment, the UAV system acquires the sensory data from digital camera and GPS/IMU sensor. Communication module transmits it to the ground server in real time. In the ground segment, the transmitted sensor data are processed to generate image-maps and the image-maps are visualized on the geo-portal. We conducted experiment to check the accuracy of the image-map using the system. Check points were obtained through ground survey in the data acquisition area. When calculating the difference between adjacent image maps, the relative accuracy was 1.58 m. We confirmed the absolute accuracy of the image map for the position measured from the individual image map. It is confirmed that the map is matched to the existing map with an absolute accuracy of 0.75 m. We confirmed the processing time of each step until the visualization of the image-map. When the image-map was generated with GSD 10 cm, it took 1.67 seconds to visualize. It is expected that the proposed system can be applied to real - time monitoring for disaster response.

A Novel Complement Fixation Pathway Initiated by SIGN-R1 Interacting with C1q in Innate Immunity

  • Kang, Young-Sun
    • Proceedings of the Microbiological Society of Korea Conference
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    • 2008.05a
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    • pp.23-25
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    • 2008
  • Serum complement proteins comprise an important system that is responsible for several innate and adaptive immune defence mechanisms. There were three well described pathways known to lead to the generation of a C3 convertase, which catalyses the proteolysis of complement component C3, and leads to the formation of C3 opsonins (C3b, iC3b and C3d) that fix to bacteria. A pivotal step in the complement pathway is the assembly of a C3 convertase, which digests the C3 complement component to form microbial-binding C3 fragments recognized by leukocytes. The spleen clears microorganisms from the blood. Individuals lacking this organ are more susceptible to Streptococcus pneumoniae. Innate resistance to S. pneumoniae has previously been shown to involve complement components C3 and C4, however this resistance has only a partial requirement for mediators of these three pathways, such as immunoglobulin, factor B and mannose-binding lectin. Therefore it was likely that spleen and complement system provide resistance against blood-borne S. pneumoniae infection through unknown mechanism. To better understand the mechanisms involved, we studied Specific intracellular adhesion molecule-grabbing nonintegrin (SIGN)-R1. SIGN-R1, is a C-type lectin that is expressed at high levels by spleen marginal-zone macrophages and lymph-node macrophages. SIGN-R1 has previously been shown to be the main receptor for bacterial dextrans, as well as for the capsular pneumococcal polysaccharide (CPS) of S. pneumoniae. We examined the specific role of this receptor in the activation of complement. Using a monoclonal antibody that selectively downregulates SIGN-R1 expression in vivo, we show that in response to S. pneumoniae or CPS, SIGN-R1 mediates the immediate proteolysis of C3 and fixation of C3 opsonins to S. pneumoniae or to marginal-zone macrophages that had taken up CPS. These data indicate that SIGN-R1 is largely responsible for the rapid C3 convertase formation induced by S. pneumoniae in the spleen of mice. Also, we found that SIGN-R1 directly binds C1q and that C3 fixation by SIGN-R1 requires C1q and C4 but not factor B or immunoglobulin. Traditionally C3 convertase can be formed by the classical C1q- and immunoglobulin-dependent pathway, the alternative factor-B-dependent pathway and the soluble mannose-binding lectin pathway. Furthermore Conditional SIGN-R1 knockout mice developed deficits in C3 catabolism when given S. pneumoniae or its capsular polysaccharide intravenously. There were marked reductions in proteolysis of serum C3, deposition of C3 on organisms within SIGN-$R1^+$ spleen macrophages, and formation of C3 ligands. The transmembrane lectin SIGN-R1 therefore contributes to innate resistance by an unusual C3 activation pathway. We propose that in the SIGN-R1 mediated complement activation pathway, after binding to polysaccharide, SIGN-R1 captures C1q. SIGN-R1 can then, in association with several other complement proteins including C4, lead to the formation of a C3 convertase and fixation of C3. Therefore, this new pathway for C3 fixation by SIGN-R1, which is unusual as it is a classical C1q-dependent pathway that does not require immuno globulin, contributes to innate immune resistance to certain encapsulated microorganisms.

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Determination of Haloperidol Serum Levels in Psychiatric Patients with Gas Chromatography-Nitrogen Phosphorus Detection (GC/NPD를 이용한 정신분열증 환자의 혈중 Haloperidol 정량분석)

  • Paik, Man-Jeong;Kang, Bo-Kyoung;Lee, Kyoung-Ok;Shin, Ho-Sang
    • Analytical Science and Technology
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    • v.11 no.3
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    • pp.161-166
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    • 1998
  • Analytical method of haloperidol (HAL) in serum which has been widely used in therapy of schizophrenic disorders is developed. Gas chromatography/nitrogen-phosphorus detection (GC/NPD) was used for this study. Bromoperidol was used as an internal standard and diethylether as a solvent of three-step extraction. The extraction yield in this procedure was $67.5{\pm}1.9%$ at 15 ng/mL. A good linear response in the range of 1~40 ng/mL was obtained with correlation coefficient of $r^2=0.999$. Detection limit was 0.5 ng/mL when 2 mL of serum was used. This method was applied for the analysis of HAL in serum of schizophrenic patients. After HAL decanoate (HD) was intaken as intramuscular route, HAL levels were determined at second week and forth week. From the result, the concentration of HAL at forth week appeared to 29.6% lower than those at second week. The present method showed low detection limit and high selectivity. Therefore it can be applied for the trace analysis of HAL in serum and the monitoring.

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Development of a Primary Tissue Culture Method having Greater Reliability than Isolated Cell Cultures - Steroid-Responsiveness of Uterine Myometrial and Myomatous(Leiomyomatous) Cells (자궁근종세포의 최적 초기배양 조건 확립 - 정상 자궁근세포와 자궁근종세포의 스테로이드에 대한 반응)

  • Lee, Eun-Ju;Bajracharya, Prati;Hyun, Jin-Hee;Kim, Hang-Jin;Song, Gun-Ho;Cho, Kyung-Hyun;Lee, Dong-Mok;Lee, Taek-Hoo;Chun, Sang-Sik;Choi, In-Ho
    • Development and Reproduction
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    • v.11 no.3
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    • pp.205-217
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    • 2007
  • As an initial step toward better understanding of the molecular mechanism of estrogen-dependent growth in myoma, an optimal primary cell culture condition has been developed and examined by this study. Myoma and myometrium were cultured by two different methods. Culture stability and $E_2$-responsiveness in stable culture were studied. The culture of digested tissue pieces(Method 2) was found to be a stable culture method for the myoma and myometrium showing a favorable response to estrogen. mRNA expression of PR, IGF-1 and IGF-1 receptor genes was enhanced by $E_2$. The gene responses to $E_2$ were higher in myoma compared with myometrium. Moreover, these responses were more expressive in tissues than in the surrounding cells in primary culture of normal myometrium and myoma, implying a vital role of cell communication through the extracellular matrix in maintaining the estrogen-responsiveness. The development of an improved cell culture system for myoma provides an in vitro tool to further investigate the basis of the tumor formation.

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Dynamic Characteristics Analysis of Spherical Shell with Initial Deflection(I) (초기 처짐을 갖는 Spherical Shell의 동적 특성에 관한 연구 (I) -기하학적 형상에 따른 동적 특성-)

  • 조진구
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.40 no.3
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    • pp.113-121
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    • 1998
  • The widespread use of thin shell structures has created a need for a systematic method of analysis which can adequately account for arbitrary geometric form. Therefore, the stress analysis of thin shell has been one of the more challenging areas of structural mechanics. The analysis of axisymmetric spherical shell is almost an every day occurrence in many industrial applications. A reliable and accurate finite element analysis procedure for such structures was needed. In general, the shell structures designed according to quasi-static analysis may fail under conditions of dynamic loading. For a more realistic prediction on the load carrying capacity of these shell, in addition to the dynamic effect, consideration should also include other factors such as nonlinearities in both material and geometry since these factors, in different manner, may also affect the magnitude of this capacity. The objective of this paper is to demonstrate the dynamic characteristics of spherical Shell. For these purpose, the spherical shell subjected to uniformly distributed step load was analyzed for its large displacements elasto-viscoplastic dynamic response. The results for the dynamic characteristics of spherical shell in the cases under various conditions of base-radius/central height(a/H) and thickness/shell radius(t/R) were summarized as follows: 1. The dynamic characteristics with a/H, 1) As the a/H increases, the amplitude of displacement increased. 2) The values of displacement Dynamic Magnification Factor (DMF) range from 2.9 to 6.3 in the crown of shell and the values of factor in the mid-point of shell range from 1.8 to 2.6. 3) As the a/H increases, the values of DMF in the crown of shell is decreased rapidly but the values of DMF in mid-point of shell is increased gradually. 4) The values of DMF of hoop-stresses range from 3.6 to 6.8 in the crown of shell and the values of factor in the mid-point of shell range from 2.3 to 2.6, the values of DMF of stress were larger than that of displacement. 2. The dynamic characteristics with t/R, 1) With the decrease of thickness of shell decreses, the amplitude of the displacement and the period increased. 2) The values of DMF of the displacement were range from 2.8 to 3.6 in the crown of shell and the values of factor in the mid-point of shell were range from 2.1 to 2.2.

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The effects of Hydroxyapatite nano-coating implants on healing of surgically created circumferential gap in dogs

  • Chae, Gyung-Joon;Lim, Hyun-Chang;Choi, Jung-Yoo;Chung, Sung-Min;Lee, In-Seop;Cho, Kyoo-Sung;Kim, Chong-Kwan;Choi, Seong-Ho
    • Journal of Periodontal and Implant Science
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    • v.38 no.sup2
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    • pp.373-384
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    • 2008
  • Purpose: The aim of this study is to compare the healing response of various Hydroxyapatite(HA) coated dental implants by Ion-Beam Assisted Deposition(IBAD) placed in the surgically created circumferential gap in dogs. Materials and methods: In four mongrel dogs, all mandibular premolars and the first molar were extracted. After an 8 weeks healing period, six submerged type implants were placed and the circumferential cylindrical 2mm coronal defects around the implants were made surgically with customized step drills. Groups were divided into six groups : anodized surface, anodized surface with 150nm HA and heat treatment, anodized surface with 300nm HA and heat treatment, anodized surface with 150nm HA and no heat treatment, and anodized surface with 150nm HA, heat treatment and bone graft, anodized surface with bone graft. The dogs were sacrificed following 12 weeks healing period. Specimens were analyzed histologically and histomorphometrically. Results: During the healing period, healing was uneventful and implants were well maintained. Anodized surface with HA coating and $430^{\circ}C$ heat treatment showed an improved regenerative characteristics. Most of the gaps were filled with newly regenerated bone. The implant surface was covered with bone layer as base for intensive bone formation and remodeling. In case that graft the alloplastic material to the gaps, most of the coronal gaps were filled with newly formed bone and remaining graft particles. The bone-implant contact and bone density parameters showed similar results with the histological findings. The bone graft group presented the best bone-implant contact value which had statistical significance. Conclusion: Within the scope of this study, nano-scale HA coated dental implants appeared to have significant effect on the development of new bone formation. And additional bone graft is an effective method in overcoming the gaps around the implants.

Solution-Processed Nontoxic and Abundant $Cu_2ZnSnS_4$ for Thin-Film Solar Cells

  • Mun, Ju-Ho
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2012.05a
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    • pp.65-65
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    • 2012
  • Copper zinc tin sulfide ($Cu_2ZnSnS_4$, CZTS) is a very promising material as a low cost absorber alternative to other chalcopyrite-type semiconductors based on Ga or In because of the abundant and economical elements. In addition, CZTS has a band-gap energy of 1.4~1.5eV and large absorption coefficient over ${\sim}10^4cm^{-1}$, which is similar to those of $Cu(In,Ga)Se_2$(CIGS) regarded as one of the most successful absorber materials for high efficient solar cell. Most previous works on the fabrication of CZTS thin films were based on the vacuum deposition such as thermal evaporation and RF magnetron sputtering. Although the vacuum deposition has been widely adopted, it is quite expensive and complicated. In this regard, the solution processes such as sol-gel method, nanocrystal dispersion and hybrid slurry method have been developed for easy and cost-effective fabrication of CZTS film. Among these methods, the hybrid slurry method is favorable to make high crystalline and dense absorber layer. However, this method has the demerit using the toxic and explosive hydrazine solvent, which has severe limitation for common use. With these considerations, it is highly desirable to develop a robust, easily scalable and relatively safe solution-based process for the fabrication of a high quality CZTS absorber layer. Here, we demonstrate the fabrication of a high quality CZTS absorber layer with a thickness of 1.5~2.0 ${\mu}m$ and micrometer-scaled grains using two different non-vacuum approaches. The first solution-processing approach includes air-stable non-toxic solvent-based inks in which the commercially available precursor nanoparticles are dispersed in ethanol. Our readily achievable air-stable precursor ink, without the involvement of complex particle synthesis, high toxic solvents, or organic additives, facilitates a convenient method to fabricate a high quality CZTS absorber layer with uniform surface composition and across the film depth when annealed at $530^{\circ}C$. The conversion efficiency and fill factor for the non-toxic ink based solar cells are 5.14% and 52.8%, respectively. The other method is based on the nanocrystal dispersions that are a key ingredient in the deposition of thermally annealed absorber layers. We report a facile synthetic method to produce phase-pure CZTS nanocrystals capped with less toxic and more easily removable ligands. The resulting CZTS nanoparticle dispersion enables us to fabricate uniform, crack-free absorber layer onto Mo-coated soda-lime glass at $500^{\circ}C$, which exhibits a robust and reproducible photovoltaic response. Our simple and less-toxic approach for the fabrication of CZTS layer, reported here, will be the first step in realizing the low-cost solution-processed CZTS solar cell with high efficiency.

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