• Title/Summary/Keyword: Transport functions

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Local call processing delay of the control network in ATM switching system (ATM 교환시스템 제어계의 자국호 처리 지연 성능평가)

  • 여환근;송광석;노승환;기장근
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.12
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    • pp.3144-3153
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    • 1996
  • ATM switching system is made up of transport network and control newrk according to its functions. The control device, basic part of control network must be developed before developing any other functions, and control device must be stable and need high reliability. Out distributed ATM switching system consists of several ALSs that provides variable local call services, and an ACS that interconnect among several ALSs. Eech ALS has CCCP that takes charage of call and connection control functions, and ACS has an OMP that takes charge of OA&M(Operation, Administration and Maintenance) functios. In this paper, we analyzed the performance evaluation of control device that manipulate subscriber's call based on ITU-T Q.2931 standard protocol messages and Interprocessor communication messages. As a result of simulation when the number of ALS is under 22, as the call arrival rate increase the processor utilization of CCCP increase rapidly than that of OMP. When the number of ALS is incremented to 22, the processor utilization of CCCP is balanced with the of OMP, and when the number of ALS exceeds 22, the processor utiliztion of OMP increase rapidly. Also if messary processing time of OMP is 1.35 times that of CCCP, processor utilizations of CCCP and OMP is equal.

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Auxin-responsive SMALL AUXIN UP RNA genes : recent research progress and its application for crop improvement (옥신 반응 SMALL AUXIN UP RNA 유전자의 최근 연구 동향 및 작물 개량을 위한 적용)

  • Lee, Sang Ho
    • Journal of Plant Biotechnology
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    • v.40 no.2
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    • pp.59-64
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    • 2013
  • Auxin is a key plant hormone which regulates overall plant growth development. A number of researches to investigate auxin signaling identified three major classes of early auxin response genes: AUX/IAA, GH3 and SMALL AUXIN UP RNA (SAUR). Among these genes, in planta functions of SAUR gene family are largely ambiguous, while both AUX/IAA and GH3 genes are analyzed to mediate negative feedback on auxin response. SAUR genes encode small plant-specific proteins. SAUR gene products are highly unstable and transiently expressed in the tissue- and developmental-specific manners in response to auxin and various environmental stimuli. In the decades, molecular and genetic approaches to elucidate in planta functions of SAURs have been hampered by several factors such as the unstable molecular features and functional redundancy among them. However, a series of recent studies focusing on several subgroups of SAUR gene family made significant progress in our understanding of its biochemical and physiological functions. These works suggest that many SAUR proteins mainly regulate auxin-related cell expansion and auxin transport. In this review, the recent progress in SAUR research and prospects for crop improvement through its genetic manipulation are discussed.

Damage detection in Ca-Non Bridge using transmissibility and artificial neural networks

  • Nguyen, Duong H.;Bui, Thanh T.;De Roeck, Guido;Wahab, Magd Abdel
    • Structural Engineering and Mechanics
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    • v.71 no.2
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    • pp.175-183
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    • 2019
  • This paper deals with damage detection in a girder bridge using transmissibility functions as input data to Artificial Neural Networks (ANNs). The original contribution in this work is that these two novel methods are combined to detect damage in a bridge. The damage was simulated in a real bridge in Vietnam, i.e. Ca-Non Bridge. Finite Element Method (FEM) of this bridge was used to show the reliability of the proposed technique. The vibration responses at some points of the bridge under a moving truck are simulated and used to calculate the transmissibility functions. These functions are then used as input data to train the ANNs, in which the target is the location and the severity of the damage in the bridge. After training successfully, the network can be used to assess the damage. Although simulated responses data are used in this paper, the practical application of the technique to real bridge data is potentially high.

Effect of Cadmium on Organic Acid Transport System in Renal Basolateral Membrane

  • Kim, Ghi-Chan;Kim, Kyoung-Ryong;Kim, Jee-Yeun;Park, Yang-Saeng
    • The Korean Journal of Physiology
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    • v.30 no.2
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    • pp.279-288
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    • 1996
  • Chronic exposure to cadmium impairs various renal tubular functions, including organic acid (anion) secretion. To investigate the mechanism of cadmium-induced alterations in the organic anion transport system, kinetics of p-aminohippurate (PAH) uptake was studied in renal cortical basolateral membrane vesicles (BLMV) isolated from cadmium-intoxicated rats (adult male Sprague-Dawley). Cadmium intoxication was induced by subcutaneous injections of $CdCl_{2}$ (2 mg Cd/kg per day) for 3 weeks. The renal plasma membrane vesicles were prepared by Percoll gradient centrifugation. The vesicular uptake of $^{14}C$-PAH was determined by rapid filtration technique using Millipore filter. Cadmium intoxication resulted in a marked attenuation of $Na^{+}$-dependent, ${\alpha}$-ketoglutarate (${\alpha}$KG)-driven PAH uptake with no changes in $Na^{+}$ and ${\alpha}$KG-independent transport component. Kinetic analysis indicated that Vmax, but not Km, of the $Na^{+}$-dependent, ${\alpha}$KG-driven component was reduced. A similar reduction of $Na^{+}$-dependent, ${\alpha}$KG-driven PAH uptake was observed in normal membrane vesicles directly exposed to inorganic cadmium in vitro, and this was accompanied by an inhibition of both $Na^{+}$-dependent ${\alpha}$KG uptake and ${\alpha}$KG-PAH exchange activity. These results indicate that during chronic exposure to cadmium, free cadmium ions liberated in the proximal tubular cytoplasm directly interact with the basolateral membrane and impair the active transport capacity for organic anions, most likely due to an inhibition of both $Na^{+}$-dicarboxylate cotransporter and dicarboxylate-organic anion antiporter activities.

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Expressed Sequence Tag Analysis of Toxic Alexandrium tamarense and Identification of Saxitoxin Biosynthetic Genes (독성 Alexandrium tamarense 의 EST 분석 및 삭시톡신 생합성 유전자의 확인)

  • Chang, Man;Lee, Juyun;Chung, Youngjae;Lee, Gunsup;Kim, Dongguin;Lee, Taek-Kyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.7
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    • pp.3582-3588
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    • 2013
  • Expressed sequence tag (EST) library was constructed from A. tamarense. Base sequences of EST clones were analyzed and saxitoxin biosynthesis-related genes were cloned. Sequences of 827 clones were analyzed and 564 EST were functionally clustered using Blast searches against GenBank. Main genes in the EST had functions on cellular organization, cell metabolism, energy, cell cycle and DNA processing, cellular transport and transport, cell rescue, defense, death and aging, and transcription. Moreover, expression of S-adenosylmethionine synthetase and H2A histone family genes were increased in the toxic A. tamarense. These results show that two genes could be a good biomarkers for the detection of saxitoxin biosynthesis in the A. tamarense.

Physiological, Pharmacological and Toxicological Implications of Heterodimeric Amino Acid Transporters

  • Kanai, Yoshikatsu;Endou, Hitoshi
    • The Korean Journal of Physiology and Pharmacology
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    • v.8 no.3
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    • pp.117-127
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    • 2004
  • The heterodimeric amino acid transporter family is a subfamily of SLC7 solute transporter family which includes 14-transmembrane cationic amino acid transporters and 12-transmembrane heterodimeric amino acid transporters. The members of heterodimeric amino acid transporter family are linked via a disulfide bond to single membrane spanning glycoproteins such as 4F2hc (4F2 heavy chain) and rBAT $(related\;to\;b^0,\;^+-amino\;acid\;transporter)$. Six members are associated with 4F2hc and one is linked to rBAT. Two additional members were identified as ones associated with unknown heavy chains. The members of heterodimeric amino acid transporter family exhibit diverse substrate selectivity and are expressed in variety of tissues. They play variety of physiological roles including epithelial transport of amino acids as well as the roles to provide cells in general with amino acids for cellular nutrition. The dysfunction or hyperfunction of the members of the heterodimeric amino acid transporter family are involved in some diseases and pathologic conditions. The genetic defects of the renal and intestinal transporters $b^{0,+}AT/BAT1\;(b^{0,+}-type\;amino\;acid\;transporter/b^{0,+}-type\;amino\;acid\;transporter\;1)$ and $y^+LAT1\;(y^+L-type\;amino\;acid\;transporter\;1)$ result in the amino aciduria with sever clinical symptoms such as cystinuria and lysin uric protein intolerance, respectively. LAT1 is proposed to be involved in the progression of malignant tumor. xCT (x-C-type transporter) functions to protect cells against oxidative stress, while its over-function may be damaging neurons leading to the exacerbation of brain damage after brain ischemia. Because of broad substrate selectivity, system L transporters such as LAT1 transport amino acid-related compounds including L-Dopa and function as a drug transporter. System L also interacts with some environmental toxins with amino acid-related structure such as cysteine-conjugated methylmercury. Therefore, these transporter would be candidates for drug targets based on new therapeutic strategies.

Effects of Benzyl Alcohol on Structures and Calcium Transport Function of Biological Cell Membranes (Benzyl Alcohol이 세포막의 형태 및 Calcium 이온 이동에 미치는 영향)

  • Lee, Hwang-Hyun;Hah, Jong-Sik;Kim, Ku-Ja
    • The Korean Journal of Physiology
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    • v.21 no.2
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    • pp.157-167
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    • 1987
  • Benzyl alcohol is known to have dual effect on the red blood cell shape change. At low concentration up to 50 mM benzyl alcohol transformed the shape from discocyte to stomatocyte by preferent binding to the inner hemileaflet, however, at higher concentratransformed the shape from discocyte to stomatocyte by preferential binding to the inner monolayer, however, at higher concentration above 50 mM benzyl alcohol transformed to echinocyte by affecting both monolayers. These results suggest that the effect of benzyl alcohol on the red blood cell shape and $Ca^{++}$ transport across cardiac cell membranes to assess the effects of the drug on the structures and functions of the biological cell membranes. The results are as follows: 1) Benzyl alcohol up to 40 mM caused progressive stomatocytic shap change of the red blood cell but above 50 mM benzyl alcohol caused echinocytic shape change. 2) Benzyl alcohol up to 40 mM inhibited both osmotic hemolysis and osmotic volume change of the red blood cell in hypotonic and hypertonic NaCl solutions, respectively. 3) Benzyl alcohol inhibited both Bowditch Staircase and Wood-worth Staircase phenomena at rat left auricle. 4) Benzyl alcohol at concentration of 5 mM increased $Ca^{++}-ATPase$ activity of red blood cell ghosts slightly but above S mM benzyl alcohol inhibited the $Ca^{++}-ATPase$ activity. 5) Benzyl alcohol at concentrations of 5 mM and 10 mM increased $Ca^{++}-ATPase$ activity slightly at rat gastrocnemius muscle S.R. but above 10 mM benzyl alcohol inhibited the $Ca^{++}-ATPase$ activity. Above results indicate that benzyl alcohol inhibit water permeability and $Ca^{++}$ transport across cell membranes in part via effects on the fluidity and transition temperatures of the bulk lipid by preferential intercalation into cytoplasmic monolayer and in part via other effect on the conformational change of active sites of the $Ca^{++}-ATPase$ molecule extended in cytoplasmic face.

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A Study on the Seller's Obligation of Conformity of Transport Documents in Shipment Sales under CISG - Focused on Bill of Lading (해상송부매매에서 국제매매협약상 매도인의 서류적합의무에 관한 일고찰 - 선하증권을 중심으로 -)

  • Hur, Hai-Kwan
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.37
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    • pp.61-85
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    • 2008
  • Bills of lading are crucial in international sales on shipment terms since they guard buyers against loss of or damage to the goods in transit by giving them the rights against carriers. A bill of lading, as document of title, gives the buyer the right to demand physical possession of the goods from the carrier and enables the buyer who is in possession of damaged or short-delivered goods to sue the carrier. In this context the buyer in sales on CIF or CFR terms or FOB terms with additional services benefits from the bill of lading which functions as a receipt of goods and a evidence of the terms of the contract of carriage. Protection of such buyer's interests can be provided in the sale contract through appropriate express or implied terms on the seller's documentary obligations: Which transport document, a bill of lading or a sea waybill, is required? Who should be named as the consignee in the transport document and, in case of bill of lading, by whom should the bill be endorsed? What should be stated in the bill of lading for the quantity of the goods? How about a bill of lading that contains so called "unknown clause"? How many bills of lading for the entire contract goods should be tendered? Can a bill of lading stating that the goods have been shipped in apparent good order and condition also state that the goods were damaged after shipment? This paper seeks to provide answers for these particular questions.

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Development of a Real-Time Video Image Tracking Algorithm for Incident Detection

  • Oh, Ju-Taek;Min, Joon-Young;Heo, Byung-Do;Kim, Myung-Seob
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.7 no.4
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    • pp.49-60
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    • 2008
  • The current VIPS are not effective in safety point of view, because they are originally developed for mimicking loop detectors. Therefore, it is important to identify vehicle trajectories in real time, because recognizing vehicle movements over a detection zone enables to identify which situations are hazardous, and what causes them to be hazardous. In order to improve limited safety functions of the current VIPS, this research has developed a computer vision system of monitoring individual vehicle trajectories based on image processing, and offer the detailed information, for example, incident detection and conflict as well as traffic information via tracking image detectors. This system is capable of recognizing individual vehicle maneuvers and increasing the effectiveness of various traffic situations. Experiments were conducted for measuring the cases of incident detection and abnormal vehicle trajectory with rapid lane change.

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Carbonic anhydrase influences asymmetric sodium and acetate transport across omasum of sheep

  • Rabbani, Imtiaz;Rehman, Habib;Martens, Holger;Majeed, Khalid Abdul;Yousaf, Muhammad Shahbaz;Rehman, Zia Ur
    • Animal Bioscience
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    • v.34 no.5
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    • pp.880-885
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    • 2021
  • Objective: Omasum is an important site for the absorption of short chain fatty acids. The major route for the transport of acetate is via sodium hydrogen exchanger (NHE). However, a discrepancy in the symmetry of sodium and acetate transport has been previously reported, the mechanism of which is unclear. In this study, we investigated the possible role of carbonic anhydrase (CA) for this asymmetry. Methods: Omasal tissues were isolated from healthy sheep (N = 3) and divided into four groups; pH 7.4 and 6.4 alone and in combination with Ethoxzolamide. Electrophysiological measurements were made using Ussing chamber and the electrical measurements were made using computer controlled voltage clamp apparatus. Effect(s) of CA inhibitor on acetate and sodium transport flux rate of Na22 and 14C-acetate was measured in three different flux time periods. Data were presented as mean±standard deviation and level of significance was ascertained at p≤0.05. Results: Mucosal to serosal flux of Na (JmsNa) was greater than mucosal to serosal flux of acetate (JmsAc) when the pH was decreased from 7.4 to 6.4. However, the addition of CA inhibitor almost completely abolished this discrepancy (JmsNa ≈ JmsAc). Conclusion: The results of the present study suggest that the additional protons required to drive the NHE were provided by the CA enzyme in the isolated omasal epithelium. The findings of this study also suggest that the functions of CA may be exploited for better absorption in omasum.