• Title/Summary/Keyword: challenge

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Effect of Copper on Plasma Ceruloplasmin and Antioxidant Ability in Broiler Chickens Challenged by Lipopolysaccharide

  • Song, Zhigang;Zhu, Lixian;Zhao, Tong;Jiao, Hongchao;Lin, Hai
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.10
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    • pp.1400-1406
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    • 2009
  • The effects of dietary copper (Cu) supplementation in broiler chickens challenged with a single injection of Salmonella typhymurium lipopolysaccharide (LPS) on the antioxidant capacity and plasma levels of ceruloplasmin (Cp) were evaluated. The broiler chickens were provided with a basal diet or diets supplemented with 8 and 50 mg/kg Cu from 1d of age. At 25d of age, 48 chickens with similar body weight were selected from each diet. Half of the chickens in each dietary treatment were injected intraperitoneally (i.p.) with LPS (1 mg/kg body weight). The other half was injected with saline, serving as the control. Body weight gain and feed consumption were significantly suppressed by LPS challenge during the first 12-h after injection, regardless of dietary Cu levels. Feed efficiency was reduced by LPS injection during the 72-h experimental period. Dietary Cu levels had no significant effect (p>0.05) on the plasma ceruloplasmin concentrations in chickens injected with saline. In contrast, high dietary level of Cu elevated plasma Cp levels in chickens with LPS challenge. Short-term LPS challenge had no significant effect on the antioxidant ability of broilers, as indicated by superoxide dismutase, ferric reducing/antioxidant power and the thiobarbituric acid reacting substances in the plasma. The result suggests that high dietary Cu level (as much as 50 mg/kg supplementation) is favorable for coping with short-term LPS challenge through upregulating plasma Cp levels.

Effect of frozen storage and various concentrations of sucrose media on survivability of enterotoxigenic Escherichia coli (ETEC) for oral challenge of weaner pigs

  • Cho, Hyun Min;Kang, Joo Won;Kim, Yeong Kuk;Lee, Joo Bin;Oh, Chan Yi;Heo, Jung Min;Yi, Young-Joo
    • Korean Journal of Agricultural Science
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    • v.43 no.5
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    • pp.788-793
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    • 2016
  • Post-weaning diarrhea (PWD), mostly caused by enterotoxigenic Escherichia coli (ETEC), remains to be a major source of economic loss in swine industry. The use of the ETEC-oral challenge model is often applied to mimic unsanitary commercial swine farm conditions where pathogens and unknown complex microbes exist and can cause severe infections in pigs. The purpose of this study was (1) to estimate ETEC density using spectrophotometric computation, (2) to determine survivability of ETEC after storing at $-20^{\circ}C$ for 7 days, and (3) to evaluate survivability of ETEC after blending with diluted sweeteners (0, 5, 10, 20, and 40% sucrose in phosphate buffered saline [PBS]). Cell density was quantified using UV-VIS spectrophotometer and counting ETEC colony forming units (cfu) at 0, 30, 60, 90, 120, 150, 180, 210, and 240 min. The established linear equation ($y=0.0031x^2-0.0079x+0.0043$ and $y=0.0046x^2-0.0151x+0.0113$) was used for robust quantification of each ETEC cell density. ETEC stored at $-20^{\circ}C$ showed 108 cfu/mL after thawing and incubation. When ETEC was blended with sweeteners (20 and 40%), survival of ETEC was decreased by 58 and 54% in 5 min post blending. However, addition of 20% of sweetener resulted in a higher survivability than those with other media concentrations. Therefore, the use of ETEC-oral challenge model would be possible as a stable method if we could confirm the appropriate medium that increases survivability of ETEC in weaner pigs.

A Study on the Attitude toward Online Game-based Edutainment (온라인게임 기반 에듀테인먼트에 관한 태도 연구)

  • Park, Seong-Taek;Kwon, Hye-Young;Kim, Tae-Ung;Jang, Woo-Jung
    • Journal of Digital Convergence
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    • v.10 no.3
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    • pp.251-263
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    • 2012
  • Edutainment refers to the form of entertainment designed to educate as well as to amuse. It typically seeks to instruct its audience by embedding messages or educational contents in some familiar form of entertainment such as computer games, films, websites, multimedia software, etc. The purpose of this study is to identify the determinants of attitude toward online game-based edutainment. This study proposes the attitude, fun, usefulness, social interaction, challenge, and educational story as major research variables, and collected the survey responses from game players having experiences with online game-based edutainment. Factor analysis confirmed that 19 questions can be categorized into 6 factors : attitude, fun, usefulness, social interaction, challenge, and educational story. Regression analysis shows that fun, usefulness and educational story significantly and directly affect the attitude toward these edutainment games, and that educational story influences the level of usefulness. In addition, challenge and social interaction were found to have significant impact on fun. In conclusion, the wider implications of the findings for utilizing online game-based edutainment are provided.

Effects of Dietary Scutellaria baicalensis Extract on Growth, Feed Utilization and Challenge Test of Olive Flounder (Paralichthys olivaceus)

  • Cho, S.H.;Jeon, G.H.;Kim, H.S.;Kim, D.S.;Kim, C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.1
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    • pp.90-96
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    • 2013
  • Effects of dietary Scutellaria baicalensis extract (SBE) on growth, feed utilization and challenge test of olive flounder (Paralichthys olivaceus) were determined. Six hundred thirty fish averaging 5.0 g were distributed into 18, 180-L tanks. Six experimental diets were prepared in triplicate: SBE-0, SBE-0.5, SBE-1, SBE-2, SBE-3 and SBE-5 diets containing SBE at the concentrations of 0, 0.5, 1, 2, 3 and 5%, respectively. Fish were hand-fed to apparent satiation twice a day for 8 wks. At the end of 8-wk feeding trial, ten fish from each tank were infected by Edwardsiella tarda for challenge test. Survival and weight gain of fish were not affected by dietary concentrations of SBE. However, specific growth rate of fish fed the SBE-2 diet was higher than that of fish fed the SBE-0, SBE-1, SBE-3 and SBE-5 diets. Neither feed efficiency nor serum chemical composition of fish was affected by dietary concentrations of SBE. The cumulative mortality of fish fed the SBE-0 diet was 100% at 96 h after E. tarda infection, but 77 to 87% for fish fed the other diets. Dietary inclusion of 2% SBE appears to be recommendable to improve specific growth rate of fish and SBE had the potential to mitigate mortality of fish at E. tarda infection.

Performance Evaluation of Recurrent Neural Network Algorithms for Recommendation System in E-commerce (전자상거래 추천시스템을 위한 순환신경망 알고리즘들의 성능평가)

  • Seo, Jihye;Yong, Hwan-Seung
    • KIISE Transactions on Computing Practices
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    • v.23 no.7
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    • pp.440-445
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    • 2017
  • Due to the advance of e-commerce systems, the number of people using online shopping and products has significantly increased. Therefore, the need for an accurate recommendation system is becoming increasingly more important. Recurrent neural network is a deep-learning algorithm that utilizes sequential information in training. In this paper, an evaluation is performed on the application of recurrent neural networks to recommendation systems. We evaluated three recurrent algorithms (RNN, LSTM and GRU) and three optimal algorithms(Adagrad, RMSProp and Adam) which are commonly used. In the experiments, we used the TensorFlow open source library produced by Google and e-commerce session data from RecSys Challenge 2015. The results using the optimal hyperparameters found in this study are compared with those of RecSys Challenge 2015 participants.

DESIGN OF AN UNMANNED GROUND VEHICLE, TAILGATOR THEORY AND PRACTICE

  • KIM S. G.;GALLUZZO T.;MACARTHUR D.;SOLANKI S.;ZAWODNY E.;KENT D.;KIM J. H.;CRANE C. D.
    • International Journal of Automotive Technology
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    • v.7 no.1
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    • pp.83-90
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    • 2006
  • The purpose of this paper is to describe the design and implementation of an unmanned ground vehicle, called the TailGator at CIMAR (Center for Intelligent Machines and Robotics) of the University of Florida. The TailGator is a gas powered, four-wheeled vehicle that was designed for the AUVSI Intelligent Ground Vehicle Competition and has been tested in the contest for 2 years. The vehicle control model and design of the sensory systems are described. The competition is comprised of two events called the Autonomous Challenge and the Navigation Challenge: For the autonomous challenge, line following, obstacle avoidance, and detection are required. Line following is accomplished with a camera system. Obstacle avoidance and detection are accomplished with a laser scanner. For the navigation challenge, waypoint following and obstacle detection are required. The waypoint navigation is implemented with a global positioning system. The TailGator has provided an educational test bed for not only the contest requirements but also other studies in developing artificial intelligence algorithms such as adaptive control, creative control, automatic calibration, and internet-base control. The significance of this effort is in helping engineering and technology students understand the transition from theory to practice.