• Title/Summary/Keyword: challenge-response

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Efficient Security Mechanism using Light-weight Data Origin Authentication in Sensor Networks (경량화 데이터 Origin 인증을 통한 효율적인 센서 네트워크 보안에 관한 연구)

  • Park, Min-Ho;Lee, Chung-Keun;Son, Ju-Hyung;Seo, Seung-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.5A
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    • pp.402-408
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    • 2007
  • There are many weaknesses in sensor networks due to hardware limitation of sensor nodes besides the vulnerabilities of a wireless channel. In order to provide sensor networks with security, we should find out the approaches different from ones in existing wireless networks; the security mechanism in sensor network should be light-weighted and not degrade network performance. Sowe proposed a novel data origin authentication satisfying both of being light-weighted and maintaining network performance by using Unique Random Sequence Code. This scheme uses a challenge-response authentication consisting of a query code and a response code. In this paper, we show how to make a Unique Random Sequence Code and how to use it for data origin authentication.

Transcriptional analysis of olive flounder lectins in response to VHSV infection

  • Lee, Young Mee;Noh, Jae Koo;Kim, Hyun Chul;Park, Choul-Ji;Park, Jong-Won;Noh, Gyeong Eon;Kim, Woo-Jin;Kim, Kyung-Kil
    • Journal of fish pathology
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    • v.29 no.1
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    • pp.13-23
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    • 2016
  • Lectins play significant roles in the innate immune responses through binding to pathogen-associated molecular patterns (PAMPs) on the surfaces of microorganisms. In the present study, tissue distribution and expression analysis of olive flounder lectins were performed after viral hemorrhagic septicemia virus (VHSV) challenge. Fish egg lectin and serum lectin were found to be predominantly expressed in the gills and liver, these results indicate that the transcript expression of olive flounder lectins is concentrated in immune-related tissues. Following a VHSV challenge, an overall increase in the transcript levels of the genes was observed and the expression patterns were distinctly divided into early and later responses during VHSV infection. In conclusion, olive flounder lectins are specifically expressed in immune-related organs and induced in both the immediate and long-lasting immune responses to VHSV in the olive flounder. These results indicate that lectins may be play important roles in the host defense mechanism and involved in the innate and adaptive immune response to viruses in fish.

Efficient membrane element for cyclic response of RC panels

  • Tesser, Lepoldo;Talledo, Diego A.
    • Computers and Concrete
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    • v.20 no.3
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    • pp.351-360
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    • 2017
  • This paper presents an efficient membrane finite element for the cyclic inelastic response analysis of RC structures under complex plane stress states including shear. The model strikes a balance between accuracy and numerical efficiency to meet the challenge of shear wall simulations in earthquake engineering practice. The concrete material model at the integration points of the finite element is based on damage plasticity with two damage parameters. All reinforcing bars with the same orientation are represented by an embedded orthotropic steel layer based on uniaxial stress-strain relation, so that the dowel and bond-slip effect of the reinforcing steel are presently neglected in the interest of computational efficiency. The model is validated with significant experimental results of the cyclic response of RC panels with uniform stress states.

A Delayed Cutaneous Hypersensitivity Induced with 2, 4-Dinitrochlorobenzene in Ducks and Chickens (2, 4-Dinitrochlorobenzene으로 유발(誘發)된 오리와 닭의 지연형(遲延型) 피부과민증(皮膚過敏症))

  • Lee, Chai-yong;Lee, Chung-gil;Lee, Joo-muk
    • Korean Journal of Veterinary Research
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    • v.26 no.1
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    • pp.149-156
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    • 1986
  • An experiment was carried out to measure the cellular immune response in the animals by sensitizing the animals with 2, 4-dinitrochlorobenzene(DNCB). The fowls could be sensitized with primary application of DNCB. The sensitizing and challenge dose was standardized. Heterophils were prominent in the early inflammatory response in the superficial and deep dermal regions with scattering of eosinophils. The histological response in the fowls was characteristic of a delayed hypersensitivity reaction.

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Study on the Thermal Transient Response of TSV Considering the Effect of Electronic-Thermal Coupling

  • Li, Chunquan;Zou, Meng-Qiang;Shang, Yuling;Zhang, Ming
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.15 no.3
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    • pp.356-364
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    • 2015
  • The transmission performance of TSV considering the effect of electronic-thermal coupling is an new challenge in three dimension integrated circuit. This paper presents the thermal equivalent circuit (TEC) model of the TSV, and discussed the thermal equivalent parameters for TSV. Si layer is equivalent to transmission line according to its thermal characteristic. Thermal transient response (TTR) of TSV considering electronic-thermal coupling effects are proposed, iteration flow electronic-thermal coupling for TSV is analyzed. Furthermore, the influences of TTR are investigated with the non-coupling and considering coupling for TSV. Finally, the relationship among temperature, thickness of $SiO_2$, radius of via and frequency of excitation source are addressed, which are verified by the simulation.

A Session Key Exchange Scheme for Authentication and SDP Encryption to Protect P2P SPIT in SIP (SIP P2P 스팸 방지를 위한 인증 및 SDP 암호화 키 교환 기법)

  • Jang, Yu-Jung;Choi, Jae-Sic;Choi, Jae-Duck;Won, Yoo-Jae;Cho, Young-Duk;Jung, Sou-Hwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.12B
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    • pp.750-757
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    • 2007
  • This paper analyzes spam threats and proposes key exchange scheme for user authentication and SDP encryption to protect potential spam threats in SIP-based VoIP services. The existing HTTP digest authentication scheme exchanges many message because challenge is sent for every establishment of the session and doesn't provide a confidentiality of SDP. To protect SPIT, our scheme exchanges initial nonce and a session master key for authentication and SDP encryption during registration. In our scheme, the challenge and response procedure is not necessary and the communication overhead is much less than applying S/MIME or TLS.

Effects of Dietary Additives and Early Feeding on Performance, Gut Development and Immune Status of Broiler Chickens Challenged with Clostridium perfringens

  • Ao, Z.;Kocher, A.;Choct, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.4
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    • pp.541-551
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    • 2012
  • The effects of dietary additives and holding time on resistance and resilience of broiler chickens to Clostridium perfringens challenge were investigated by offering four dietary treatments. These were a negative control (basal), a positive control (Zn-bacitracin) and two dietary additives, mannanoligosaccharides (MOS), and acidifier. Two holding times included (a) immediate access to feed and water post hatch (FED) and (b) access to both feed and water 48 h post hatch (HELD). Chicks fed Zn-bacitracin had no intestinal lesions attributed to necrotic enteritis (NE), whereas chicks fed both MOS or acidifier showed signs of NE related lesions. All dietary treatments were effective in reducing the numbers of C. perfringens in the ileum post challenge. The FED chicks had heavier body weight and numerically lower mortality. The FED chicks also showed stronger immune responses to NE challenge, showing enhanced (p<0.05) proliferation of T-cells. Early feeding of the MOS supplemented diet increased (p<0.05) IL-6 production. The relative bursa weight of the FED chicks was heavier at d 21 (p<0.05). All the additives increased the relative spleen weight of the HELD chicks at d 14 (p<0.05). The FED chicks had increased villus height and reduced crypt depth, and hence an increased villus/crypt ratio, especially in the jejunum at d 14 (p<0.05). The same was true for the HELD chicks given dietary additives (p<0.05). It may be concluded that the chicks with early access to dietary additives showed enhanced immune response and gut development, under C. perfringens challenge. The findings of this study shed light on managerial and nutritional strategies that could be used to prevent NE in the broiler industry without the use of in-feed antibiotics.

Effects of dietary lysozyme supplementation on growth performance, nutrient digestibility, intestinal microbiota, and blood profiles of weanling pigs challenged with Escherichia coli

  • Park, Jae Hong;Sureshkumar, Shanmugam;Kim, In Ho
    • Journal of Animal Science and Technology
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    • v.63 no.3
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    • pp.501-509
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    • 2021
  • The aim of this was evaluate the efficacy of lysozyme on growth performance, nutrient digestibility, excreta microflora population, and blood profiles of weanling pigs under Escherichia coli (E. coli) challenge. A total of 30 piglets weaned at 25 days, 7.46 kg body weight, were assigned to three dietary treatments, composed of five replications, two piglets per replication, for 7 days. The dietary treatment groups were negative control (NC; without antibiotics and lysozyme), positive control (PC; NC + antibiotics), lysozyme (NC + 0.1% lysozyme). All piglets were challenged orally with 6 ml suspension, containing E. coli K88 (2 × 109 CFU/mL). Dietary supplementation with lysozyme and PC resulted in no significant differences in average daily gain and gain to feed efficiency. Weanling pigs fed with E. coli challenge with lysozyme and PC treatments had significantly enhanced nutrient retentions of dry matter and energy (p < 0.05); however, there was a tendency to increase nitrogen digestibility. Furthermore, dietary inclusion of lysozyme and antibiotics treatment groups had a beneficial effect on excreta, ileal, and cecal of the fecal microbial population as decreased E. coli (p < 0.05) counts, without effects on lactobacillus counts. A significant effect were observed on a white blood cells, epinephrine and cortisol concentrations were reduced in piglets fed diets containing E. coli challenge with lysozyme and antibiotics supplementation comparison with the NC group. Therefore, the present data indicate that lysozyme in diet could ameliorate the experimental stress response induced by E. coli in piglets by decreasing intestinal E. coli, white blood cells and stress hormones and improving nutrient digestibility.

Effects of Achyranthes Bidentata Polysaccharide on Growth Performance, Immunological, Adrenal, and Somatotropic Responses of Weaned Pigs Challenged with Escherichia coli Lipopolysaccharide

  • Guo, Guanglun;Liu, Yulan;Fan, Wei;Han, Jie;Hou, Yongqing;Yin, Yulong;Zhu, Huiling;Ding, Binying;Shi, Junxia;Lu, Jing;Wang, Huirong;Chao, Jin;Qu, Yonghua
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.8
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    • pp.1189-1195
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    • 2008
  • A study was conducted with 48 weaned barrows ($28{\pm}3d$, $8.45{\pm}0.14kg$) to determine the effect of Achyranthes bidentata polysaccharide (ABPS) supplementation on pig performance, immunological, adrenal and somatotropic responses following Escherichia coli lipopolysaccharide (LPS) challenge. The experiment was a $2{\times}2$ factorial design; the main factors included diet (supplementation with 0 or 500 mg/kg ABPS) and immunological challenge (LPS or saline). On d 14 and 21 of the trial, pigs were given an intraperitoneal injection with either $100{\mu}g/kg$ BW of LPS or an equivalent amount of sterile saline. Blood samples were obtained 3 h after injection for analysis of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), prostaglandin $E_2$ ($PGE_2$), cortisol, growth hormone (GH), insulin-like growth factor (IGF)-I and immunoglobulin G (IgG). On d 2 after LPS challenge, peripheral blood lymphocyte proliferation (PBLP) was measured. LPS administration decreased average daily feed intake (ADFI) (p<0.05), had a tendency to decrease average daily gain (ADG) (p<0.10) during both the first and second challenge periods and increased (p<0.05) feed:gain ratio only during the first challenge period. ABPS tended to improve ADG (p<0.10) during the first challenge period, and improved ADG (p<0.05) and tended to improve ADFI (p<0.10) during the second challenge period. ABPS did not affect feed:gain ratio. An interaction (p<0.05) between LPS challenge and diet was observed for the plasma concentrations of TNF-${\alpha}$, $PGE_2$ and cortisol after both LPS challenges such that, among LPS-treated pigs, pigs fed the ABPS diet were lower for these indices than those receiving the control diet. In contrast, pigs fed the ABPS diet had higher IGF-I (p<0.05) compared with those fed the control diet. No effect of diet, LPS challenge or both on GH and IgG was observed after both LPS administrations. LPS challenge increased PBLP when these cells were incubated with $8{\mu}g/ml$ of LPS during both the challenge periods, and did likewise when incubated with $8{\mu}g/ml$ of concanavalin A only after the first challenge. ABPS had no effect on PBLP. These data demonstrate that ABPS alters the release of pro-inflammatory cytokines following an immunological challenge, which might enable pigs to achieve better performance.

Change of Soluble RANTES Levels in Serum from Pateints with Atopic Bronchial Asthma (기관지 천식 환자에서 기관지 특이항원 유발검사후 RANTES농도의 변화)

  • Rhee, Yang-Keun;Kim, Jae-Hean;Lee, Yong-Chul
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.2
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    • pp.182-189
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    • 1996
  • Background : RANTES is associated with chemotaxis and activation of eosinophils. RANTES is up-regulated in allegic inflammation and play a critical role in the pathogenesis of allegic inflammation. Recently, circulating form of RANTES have been identified in the peripheral blood. Method : In the present study, we measured soluble RANTES levels in 17 patients with atopic brochial asthma (8 patients: early response to allegen challenge, 8 patients : early and late response to allergen challenge) on 30mins, 2hrs and 8 hrs after allergen challenge with house dust mite, prechallenge period. Result : RANTES levels in sera from patients with bronchial astma in prechallenge conditions were higher than in normal control subjects. But, RANTES levels in sera from patients with bronchial asthma in 30mins, 2hrs and 8hrs after challenge were no significantly higher than prechallenge conditions. Conclusion : These results suggest that RANTES plays a role in the pathogenesis of patients with atopic bronchial asthma and may be related to persistence of subclinical allergic inflammation.

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