• Title/Summary/Keyword: exposure limit

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Dynamics Associated with Prolonged Ensiling and Aerobic Deterioration of Total Mixed Ration Silage Containing Whole Crop Corn

  • Wang, Huili;Ning, Tingting;Hao, Wei;Zheng, Mingli;Xu, Chuncheng
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.1
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    • pp.62-72
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    • 2016
  • This study investigated the dynamics associated with prolonged ensiling and aerobic deterioration of whole crop corn (WCC) silages and total mixed ration (TMR) silages containing WCC (C-TMR silages) to clarify the differences that account for the enhanced aerobic stability of TMR silages. Laboratory-scale barrel silos were randomly opened after 7, 14, 28, and 56 d of ensiling and were subjected to analyses of fermentation quality, microbial and temperature dynamics during aerobic exposure. WCC and C-TMR silages were both well preserved and microorganisms were inhibited with prolonged ensiling, including lactic acid bacteria. Yeast were inhibited to below the detection limit of 500 cfu/g fresh matter within 28 d of ensiling. Aerobic stability of both silages was enhanced with prolonged ensiling, whereas C-TMR silages were more aerobically stable than WCC silages for the same ensiling period. Besides the high moisture content, the weak aerobic stability of WCC silage is likely attributable to the higher lactic acid content and yeast count, which result from the high water-soluble carbohydrates content in WCC. After silo opening, yeast were the first to propagate and the increase in yeast levels is greater than that of other microorganisms in silages before deterioration. Besides, increased levels of aerobic bacteria were also detected before heating of WCC silages. The temperature dynamics also indicated that yeast are closely associated with the onset of the aerobic deterioration of C-TMR silage, whereas for WCC silages, besides yeast, aerobic bacteria also function in the aerobic deterioration. Therefore, the inclusion of WCC might contribute to the survival of yeast during ensiling but not influence the role of yeast in deterioration of C-TMR silages.

Effects of two litter amendments on air NH3 levels in broiler closed-houses

  • Atapattu, N.S.B.M;Lakmal, L.G.E.;Perera, P.W.A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.10
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    • pp.1500-1506
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    • 2017
  • Objective: High $NH_3$ emissions from poultry houses are reported to have negative impacts on health, welfare and safety of birds and humans, and on the environment. Objective of the present study was to determine the effects of two litter amendments on the $NH_3$ levels in broiler closed houses under hot-humid conditions. Methods: Giving a completely randomize design, nine closed houses, each housed 32,500 birds on paddy husk litter, were randomly allocated into two treatment (Mizuho; a bacterial culture mix and Rydall OE; an enzymatic biocatalyst) and control groups. $NH_3$ levels were determined thrice a day (0600, 1200, and 1800 h), at three heights from the litter surface (30, 90, and 150 cm), at 20 predetermined locations of a house, from day 1 to 41. Results: Rydall significantly reduced the $NH_3$ level compared to control and Mizuho. $NH_3$ levels at 30 cm were significantly higher than that of 90 and 150 cm. The $NH_3$ levels at 30 cm height were higher than 25 ppm level from day 9, 11, and 13 in Mizuho, control, and Rydall groups, respectively to day 41. $NH_3$ levels at 150 cm height were higher than maximum threshold limit of 50 ppm for human exposure from day 12, 14, and 15 in Mizuho, control, and Rydall groups, respectively to day 33. Being significantly different among each other, the $NH_3$ level was highest and lowest at 0600 and 1800 h. Litter amendments had no significant effects on growth performance. Rydall significantly increased the litter N content on day 24. Conclusion: It was concluded that the $NH_3$ levels of closed house broiler production facilities under tropical condition are so high that both birds and workers are exposed to above recommended levels during many days of the growing period. Compared to microbial culture, the enzymatic biocatalyst was found to be more effective in reducing $NH_3$ level.

A Study on the Internet Advertisement. Waking banner and e-mail type advertising the prime object) (인터넷 광고에 관한 연구 -배너광고와 이메일 광고를 중심으로)

  • 손상희
    • Archives of design research
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    • v.14 no.3
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    • pp.107-116
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    • 2001
  • Despite young age, Internet, as new advertising media, is actively studied worldwide. In 1995, the department of multimedia-related study was first founded in Technical Institute and has carried out the On Internet banner, user is not an object to accept only a message but has a specification to contact with banner actively having various motivation and desire. Internet advertising has various types but banner and e-mail type advertising are main stream. In the view point of recognition and concern rate, banner is very effective because it does not set limit to specific target, but is shown to unspecific audience. Acceding to studies, usage frequency and effect of e-mail type advertising is growing up. And e-mail type advertising is more active because it can target specific audience with various life style. If we can say banner is not so effective in spite of simply good exposure frequency, we can find theoritical background that e-mail type advertising is more effective internet advertising media because high click frequency. And we suppose that this study can be a guide line for measuring process of Internet advertising effect.

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Environmental Contamination and Bioavailability of Toxic Element around the Daduk Mine Area, Korea (다덕광산 주변지역에서의 독성원소들의 환경오염 및 인체흡수도)

  • ;Ben A Klinck;Yvette Moore
    • Economic and Environmental Geology
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    • v.33 no.4
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    • pp.273-282
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    • 2000
  • In order to investigate the extent and degree of arsenic and heavy metal contamination and the bioavailability of toxic elements around the abandoned mine in Korea, an environmental geochemical survey was undertaken in the Daduk mine. After appropriate preparation, tailings, soil, stream sediment, crop plant and fingernail samples were analysed for As, Cd, Cu, Pb and Zn by ICP-AES and ICP-MS. Elevated levels of 8,782 mg/kg As, 8.3 mg/kg Cd, 489 mg/kg Cu, 3,638 mg/kg Pb and 919 mg/kg Zn were found in tailings from the Daduk mine. These significant concentrations can impact on soils and sediments around the tailing ponds. Mean concentrations of As, Cd, Pb, Cu and Zn in soils are significantly higher than those in world average soil, especially for As and Pb. Element concentrations in sediments decrease with distance from the tailing ponds due to a dilution effect by the mixing of uncontaminated sediments. Arsenic and Cd are elevated in rice grains and stalks, and Cu and Zn concentrations in chinese cabbage, sesame and bean leaves are higher than the upper limit values for normal plant. Arsenic concentration in fingernails of farmers are higher than the normal level with a maximum value of 1.5 mg/kg. The post-ingestion bioavailability of toxic heavy metals in some paddy and farmland soils has been also investigated using the SBET (simple bioavailability extract test) method. The method utilises synthetic leaching fluids closelyanalogous to those of the human stomach. The quantities of As, Cd, Cu, Pb and Zn extracted from paddy soils after 1 hour indicated 15.9, 65.4, 46.2, 39.4 and 29.4% bioavailability, respectively and for farmland soils, 12.4, 26.0, 31.2, 29.3 and 19.4% bioavailability, respectively. The results of the SBET indicate that regular ingestion of soils by the local population could pose a potential health threat due to long-term toxic element exposure.

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A Mutual Authentication Protocol using Key Change Step by Step for RFID Systems (단계적 키 변환을 이용한 RFID 상호 인증 프로토콜)

  • Chung, Kyung-Ho;Kim, Kyoung-Youl;Oh, Se-Jin;Lee, Jae-Kang;Park, Yong-Soo;Ahn, Kwang-Seon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.3B
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    • pp.462-473
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    • 2010
  • The RFID system has the security problem of location tracking and user privacy. In order to solve this problem, the cryptographic access method using hash function is difficult to in real applications. Because there is a limit of computing and storage capacity of Tag, but the safety is proved. The lightweight authentication methods like HB and LMAP guarantee the high efficiency, but the safety is not enough to use. In this paper, we use the AES for RFID Authentication, and solve the problem of using fixed key with key change step by step. The symmetric keys of the tag and server are changed by the random number generated by tag, reader and server successively. This could prevent the key exposure. As a result, the output of the tag and reader always changes. These key changes could make it possible to prevent eavesdropping, replay attack, location tracking and spoofing.

Quantitative Microbial Risk Assessment for Campylobacter spp. on Ham in Korea

  • Lee, Jeeyeon;Ha, Jimyeong;Kim, Sejeong;Lee, Heeyoung;Lee, Soomin;Yoon, Yohan
    • Food Science of Animal Resources
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    • v.35 no.5
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    • pp.674-682
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    • 2015
  • The objective of this study was to evaluate the risk of illness from Campylobacter spp. on ham. To identify the hazards of Campylobacter spp. on ham, the general characteristics and microbial criteria for Campylobacter spp., and campylobacteriosis outbreaks were investigated. In the exposure assessment, the prevalence of Campylobacter spp. on ham was evaluated, and the probabilistic distributions for the temperature of ham surfaces in retail markets and home refrigerators were prepared. In addition, the raw data from the Korea National Health and Nutrition Examination Survey (KNHNES) 2012 were used to estimate the consumption amount and frequency of ham. In the hazard characterization, the Beta-Poisson model for Campylobacter spp. infection was used. For risk characterization, a simulation model was developed using the collected data, and the risk of Campylobacter spp. on ham was estimated with @RISK. The Campylobacter spp. cell counts on ham samples were below the detection limit (<0.70 Log CFU/g). The daily consumption of ham was 23.93 g per person, and the consumption frequency was 11.57%. The simulated mean value of the initial contamination level of Campylobacter spp. on ham was −3.95 Log CFU/g, and the mean value of ham for probable risk per person per day was 2.20×10−12. It is considered that the risk of foodborne illness for Campylobacter spp. was low. Furthermore, these results indicate that the microbial risk assessment of Campylobacter spp. in this study should be useful in providing scientific evidence to set up the criteria of Campylobacter spp..

An Investigation on the Technical Background for Carbon-14 Monitoring in Radioactive Effluents (원자력시설의 Carbon-14 방사성유출물에 대한 감시배경의 조사)

  • Kim, Hee-Geun;Kong, Tae-Young;Jeong, Woo-Tae;Kim, Seok-Tae
    • Journal of Radiation Protection and Research
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    • v.34 no.4
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    • pp.195-200
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    • 2009
  • effluents to the environment. The activity of carbon-14, one of the radioactive effluents, in the environment is already high level and its effect on radiation exposure to the public and the environment is insignificant; thus, NPPs did not perform the carbon-14 monitoring in effluents in the past. By the way, effluents of noble gas and particulate radioactive materials originated from nuclear fuels has been continuously reduced due to both the advancement of manufacturing and integrity technology for nuclear fuels and the improvement of operation methods of NPPs. Futhermore, the portion of dose assessment by tritium and carbon-14 to the public has been relatively increased because the lower limit of detection for low-energy beta sources, such as tritium and carbon-14, is low due to the advancement of radiation detection technology. In this paper, the technical background for carbon-14 monitoring in nuclear facilities was investigated using United States technical reports and papers. This paper also reviews whether carbon-14 monitoring is necessary or not based on the investigated documents.

A Study on the Globalization of Korean Food and Actual Conditions of Korean Restaurants in Australia by an In-Depth IntelView (호주 현지 한식당의 실태와 심층면접에 의한 한식 세계화 방안 연구)

  • Min, Kye-Hong
    • Culinary science and hospitality research
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    • v.17 no.1
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    • pp.44-57
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    • 2011
  • The purpose of this study is to suggest methods to globalize Korean food and actual conditions of Korean restaurants in Brisbane and Sunny Bank, Australia. The period of the survey was from July 19 to Aug 13, 2010. As a analysis method, in-depth interviews were conducted and the result was suggested by general arrangement in cases that responses to the interview questions were considered overlapping or similar. The result of the study on methods to globalize Korean food is as follows. First, development and improvement of favorable cuisine for Australians is essential. Second, the government should lead the promotion of food supply and dishes. Third, personnel in the food industry not only need to be trained to communicate well but also have exposure to different cultures around the world. For the limit of the study, it was difficult to secure enough samples of the subjects for an in-depth interview due to lack of numbers of Korean restaurants. In future studies, research on new methods for the globalization of Korean food should be conducted by doing research on Korean restaurants in other areas of Australia.

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Establishing a Policy Framework for the Primary Prevention of Occupational Cancer: A Proposal Based on a Prospective Health Policy Analysis

  • Veglia, Amanda;Pahwa, Manisha;Demers, Paul A.
    • Safety and Health at Work
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    • v.8 no.1
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    • pp.29-35
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    • 2017
  • Background: Despite our knowledge of the causes of cancer, millions of workers are involuntarily exposed to a wide range of known and suspected carcinogens in the workplace. To address this issue from a policy perspective, we developed a policy framework based on a prospective health policy analysis. Use of the framework was demonstrated for developing policies to prevent cancers associated with diesel engine exhaust (DEE), asbestos, and shift work, three occupational carcinogens with global reach and large cancer impact. Methods: An environmental scan of existing prospective health policy analyses was conducted to select and describe our framework parameters. These parameters were augmented by considerations unique to occupational cancer. Policy-related resources, predominantly from Canada, were used to demonstrate how the framework can be applied to cancers associated with DEE, asbestos, and shift work. Results: The parameters of the framework were: problem statement, context, jurisdictional evidence, primary prevention policy options, and key policy players and their attributes. Applying the framework to the three selected carcinogens illustrated multiple avenues for primary prevention, including establishing an occupational exposure limit for DEE, banning asbestos, and improving shift schedules. The framework emphasized the need for leadership by employers and government. Conclusion: To our knowledge, this is the first proposal for a comprehensive policy framework dedicated to the primary prevention of occupational cancer. The framework can be adapted and applied by key policy players in Canada and other countries as a guide of what parameters to consider when developing policies to protect workers' health.

Formation of Luteoskyrin by Penicillium islandicum (Penicillium islandicum에 의한 황변미독(黃變米毒) Luteoskyrin의 생성(生成))

  • Kim, Yong-Hwa;Lee, Su-Rae
    • Korean Journal of Food Science and Technology
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    • v.10 no.1
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    • pp.46-51
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    • 1978
  • One of yellowed rice toxins, luteoskyrin, was investigated with respect to its identification, quantitation and producibility by Penicillium islandicum isolated from deteriorated rice. 1) Luteoskyrin was best resolved by thin-layer chromatography with silica gel G plate impregnated with 0. 5 N oxalic acid and acetone : n-hexane : water (6 : 3 : 1.5, upper layer) solvent system. The isolated yellow spot showed maximum absorption bands at 426 and 448 nm and changed to purple color upon exposure to sunlight for $2{\sim}3$ hours. 2) Detection limit for luteoskyrin was 4 ppm in elution-colorimetry and 0.1 ppm in densitometry after TLC. Assuming that the tolerance for luteoskyrin in rice is set below 3.68 ppm, densitometry is usable for its screening in grain samples 3) Producibility of luteoskyrin by Pen. islandicum was shown to be 11 mg/g mycelial mat in liquid culture and 40 mg/g autoclaved rice.

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