• 제목/요약/키워드: Sources of variation

검색결과 609건 처리시간 0.026초

어류의 주광성에 관한 연구 6. 백색광에 대한 능성어의 반응 (Phototaxis of Fish 6. Responce of Sea-bass to the White Lights)

  • 양용림
    • 수산해양기술연구
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    • 제23권3호
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    • pp.137-143
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    • 1987
  • 빛에 대한 어류의 행동을 조사하기 위하여, 능성어 Epinephelus septemfasciatus에 빛의 세기가 서로 다른 8가지 백색인공광원으로 광자극을 주어, 그에 대한 반응을 주간과 야간으로 구분 조사한 결과는 다음과 같다. 1. 광자극에 대한 수조내의 구간별 분포는 광원에 따른 분포곡선의 형태가 서로 상이하였으며 주야간의 차이도 대단히 심했다. 2. 능성어는 광원에서 멀리 떨어진 곳에 많이 모이는 경향을 보였으나, 야간에 빛의 세기가 약한 광원 (A, B, C광원)하에서는 광원쪽에 많이 모였다. 3. 집어율이 최대가 되는 수중조도(적정조도)는 주간에 24.13 lux (15.25~35.93 lux), 야간에 0.14 lux (0.25~0.63 lux)로서 주간에 더 높았으며, 최대집어율은 주간에 20.23%, 야간에 47.30%로서 야간에 더 높았다. 4. 조명시간이 경과함에 따라 집어율은 증가한 후 감소하는 경향과 감소한 후 증가하는 경향을 보였으나, 계속 불안정하게 변동하였으며, 주야간의 차이는 뚜렷했는데 빛의 세기가 약한 광원 (A~D 광원)하에서는 야간의 집어율이, 빛의 세기가 강한 광원 (E~H 광원)하에서는 주간의 집어율이 각각 더 높았다.

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Microcystis와 공존하는 동물플랑크톤 군집의 계절변화 및 안정동위원소비의 차이 (Isotopic Differences among Zooplankton Taxa and Seasonal Variation of Zooplankton Community Coexisting with Microcystis)

  • 이재용;김재구;정유경;김범철
    • 생태와환경
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    • 제43권1호
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    • pp.1-10
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    • 2010
  • 본 연구에서는 부영양한 저수지에서 동물플랑크톤 군집의 계절변동을 파악하고 안정동위원소분석을 통해 동물플랑크톤이 Microcystis 섭식을 회피한다는 기존의 가설을 확인하고자 하였다. 요각류는 Cyclops vicinus (C. vicinus)에서 Thermocyclops taihokuensis (T. taihokuensis)로 우점종의 천이를 보였다. 계절변동에 따른 동물플랑크톤군집 밀도는 Microcystis의 밀도가 가장 높았던 6월에 가장 낮았고, 식물플랑크톤의 밀도 및 Chl. $\alpha$ 농도는 7월에 낮게 나타났다. 지각류와 요각류 사이에 $\delta^{13}C$$\delta^{15}N$는 각각 최대 $12^{\circ}/_{\circ\circ}$$4^{\circ}/_{\circ\circ}$의 차이를 보였으며, 이는 왕송저수지에서 지각류(D. galeata와 B. longirostris)와 요각류(C. vicinus)는 서로 다른 영양단계에 위치하고 다른 에너지원을 이용함을 시사하였다. Microcystis와 동물플랑크톤(지각류와 요각류)의 $\delta^{13}C$ 사이에 보이는 $3{\sim}7^{\circ}/_{\circ\circ}$의 차이는 동물플랑크톤이 Microcystis를 직접 이용하기 어렵다는 기존의 가설을 지지하였다.

서울 일부 지하철 승무원석의 PM, 이산화탄소, 일산화탄소 모니터링에 의한 실내 공기질 특성 평가 (Evaluation on Air Quality inside Subway Driver Cabin by Monitoring PM, $CO_2$, and CO Levels)

  • 곽현석;진구원;김원;양원수;최상준;박동욱
    • 한국환경보건학회지
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    • 제31권5호
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    • pp.379-386
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    • 2005
  • [ $PM_{10},\;PM_{2.5},\;CO_2\;and\;CO$ ] in driver cabins of subway line from 5 to 8 were monitored from 07:00 through 21:00 (or 19:30 or 20:00) on May. Driver cabin of subway line 7 showed the highest $PM_{10},\;PM_{2.5},\;CO_2\;and\;CO$ concentrations. General Linear Model indicated that subway line, subway location (ground and underground track) and running time (morning and afternoon) significantly influenced the concentrations of $PM_{10},\;PM_{2.5},\;CO_2\;and\;CO$ (p=0.000). Daily profile of $PM_{10},\;PM_{2.5},\;CO_2\;and\;CO$, expressed as an 30 minutes average, showed similar variation pattern over day period. These concentrations showed the highest concentrations between 07:00 and 09:00 of rush hour, slightly dropped and again rose slightly after 18:00. In correlation analysis, significant relations among $PM_{10},\;PM_{2.5},\;CO_2\;and\;CO$ were detected (p<0.01). In particular, correlation coefficient between $PM_{10}\;and\;PM_{2.5}$ was highly significant (r=0.884). Regression analysis also concluded that $PM_{10}$ concentration significantly explained 71.4% of variation of $PM_{2.5}$ concentration (p=0.000, $R^2=0.714$). Correlations by CO with $PM_{10}\;and\;PM_{2.5}$ were 0.451 and 0.520, which were higher than those by $CO_2$. Further study is needed to examine the sources of $PM_{2.5}$ and CO in subway and to compare pollutants concentration among subway lines.

계절별로 조사한 조석에 따른 아산만의 수질 변동 (Semidiurnal Tidal Variation in Water Quality in Asan Bay during four Seasons)

  • 김세희;신용식
    • 한국해양생명과학회지
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    • 제5권1호
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    • pp.25-33
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    • 2020
  • 아산만은 방조제 갑문을 통한 담수 유입과 외해인 서해로부터 해수가 유입되는 하구의 특성을 나타내는 곳으로, 반일주조형 조석을 가진 조수간만의 차가 크게 발생하는 해역이다. 하구에서 조석은 단기적인 물리·화학적 수질 특성 변화 및 생물학적 반응에 영향을 미칠 수 있어 조석에 따른 수질 변화를 파악하는 것은 중요하다. 본 연구는 아산만의 고정 정점에서 계절별로 2시간 간격으로 24시간 동안 조사하여 조석에 따른 수질 변동을 파악하고자 하였다. 연구 결과, 조위에 따른 수온과 염분의 변동이 확인되었고, 염분은 특히 조위와 유의한 양의 상관성을 보였다. 총부유물질의 경우 표층보다 저층의 농도가 높고, 조석에 따라 농도의 차이가 특히 저층에서 크게 나타났으며, 간조 시 높아지는 경향을 보였다. 영양염류인 아질산+질산성 질소도 조위 양상과 반대의 분포로 나타났으며, 상관성 분석 결과에서도 유의한 음의 상관성을 보였다. 나머지 영양염류들도 다소 약하지만 유사한 형태의 변동을 보였고, 담수 유입의 영향을 받은 7월에는 반대 경향이 더욱 명확하게 나타났다. 유기물 및 총질소, 총인의 경우 조석 주기 동안의 시간 변동이 다소 크게 나타났고, 대체적으로 조위와 반대의 분포를 보여 주었다. 입자 유기물을 제외하고 대부분 염분과 유의한 음의 상관성을 보여 무기질 영양염류와 유사하게 담수 유입이 공급원임을 암시하고 있다. 결국 아산만에서는 용존산소, pH 등 일부를 제외한 수질인자와 영양염류 및 유기물의 시간적 변동에 조석이 관여하여 단기적 영향을 미치고 있는 것으로 판단된다.

서식환경에 따른 황색포도구균의 항균제감수성 및 Phage형별의 차이 (Variation of Antimicrobial Susceptibility and Phage Types of Staphyloccus aureus Derived from Different Environmental Sources)

  • 조동택;이유철;김진모
    • 대한미생물학회지
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    • 제20권1호
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    • pp.1-11
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    • 1985
  • A total of 211 strains of Staphylococcus aureus which included 118 strains isolated from various clinical specimens of admitted patients of University Hospital with systemic or severe cases of infection and 93 strains from infected skin diseases of out-patients of dermatology clinic located in rural area, were tested for the antimicrobial susceptibility to the 12 drugs of common use and the phage typing. An these were subjected to the study of plasmid profile analysis for the molecular epidemiology of nosocomial infections. University Hospital(UH) isolates showed higher frequency of resistance than local clinic(LC) isolates against 10 drugs excluding tetracycline(Tc), and trimethoprim(Tp). The MIC of UH isolates were above than $128{\mu}g/ml$ against 9 drugs except Tc, gentamicin(Gm), and Tp, but LC isolates did not show such a high level of MIC. There was difference of MIC needed to inhibit 90% of strains(MIC90) against each drugs tested between two groups of UH and LC isolates. UH isolates showed 2 to 4 times higher value of MIC90 by two-fold serial dilution of drug concentration than LC isolates. Tp was considered as an effective drug in treatment of staphylococcal infections whereas ampicillin and Gm were appeared to be ineffective. Seventy-three strains(61.9%) of UH isolates and 70(69.9%) of LC were typable with phages from Colindale Reference Laboratory. The prevailing phage type of UH isolates belonged to lytic group II were 27 strains(22.9%) and those of LC isolates belonged to lytic group II were 23 strains(24.7%). Thirteen strains(11.0%) of UH isolates were multiply resistant to more than 5 drugs to 10 drugs but none of LC isolates. Through the lysis method of Kado and Liu followed by agarose gel electrophoresis, none of 211 strains showed plasmid profile. These results were confirmed by re-examination through the method of Birnboim and Doly.

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Validation and comparison of volume measurements using 1 multidetector computed tomography and 5 cone-beam computed tomography protocols: An in vitro study

  • Juliana Andrea Correa, Travessas;Alessandra Mendonca, dos Santos;Rodrigo Pagliarini, Buligon;Nadia Assein, Arus;Priscila Fernanda Tiecher, da Silveira;Heraldo Luis Dias, da Silveira;Mariana Boessio, Vizzotto
    • Imaging Science in Dentistry
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    • 제52권4호
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    • pp.399-408
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    • 2022
  • Purpose: The purpose of this study was to compare volume measurements obtained using 2 image software packages on Digital Imaging and Communications in Medicine (DICOM) images acquired from 1 multidetector computed tomography and 5 cone-beam computed tomography devices, using different protocols for physical volume measurements. Materials and Methods: Four pieces of bovine leg were prepared. Marrow was removed from 3 pieces, leaving cortical bone exposed. The resulting space of 1 piece was filled with water, another was filled with propylene glycol, and the third was left unfilled. The marrow in the fourth sample was left fully intact. Volume measurements were obtained after importing DICOM images into the Dolphin Imaging 11.95 and ITK-SNAP software programs. Data were analyzed using 3-way analysis of variance with a generalized linear model to determine the effects of voxel size, software, and content on percentage mean volume differences between tomographic protocols. A significance level of 0.05 was used. Results: The intraclass correlation coefficients for intraobserver and interobserver reliability were, respectively, 0.915 and 0.764 for the Dolphin software and 0.894 and 0.766 for the ITK-SNAP software. Three sources of statistically significant variation were identified: the interaction between software and content (P=0.001), the main effect of content (P=0.014), and the main effect of software (P=0.001). Voxel size was not associated with statistically significant differences in volume measurements. Conclusion: Both content and software influenced the accuracy of volume measurements, especially when the content had gray values similar to those of the adjacent tissues.

일부지역 성인여성의 사회경제적요인, 건강관련의식구조 및 식생활태도와 채소류 소비에 미치는 영향 (Influences of Socio-demographic Factors, Health-related Recognitions and Dietary Behaviors on Use and Purchasing of Vegetables among Adult Women)

  • 오혜숙
    • 한국지역사회생활과학회지
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    • 제19권4호
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    • pp.481-495
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    • 2008
  • The aim of this study was to investigate the effects of socio-demographic and health-related perceptions and twenty dietary behaviors on the superiority and preference, convenient use of and purchase motives of vegetables among 370 women(mean age 43.9) in Seoul and metropolitan and Gangwon area. Data was collected using a questionnaire developed in advanced studies. Almost all subjects rated vegetables more predominantly than grains or meats on the basis of health, diversity, and convenience to purchase. Recognition of healthly funcions of diet, purpose of diet and some dietary behaviors had influence on preference for vegetables. Those who recognized that diet had the function of disease control and prevention, knew the healthy options vegetables provide us, such as, preventing us from geriatric diseases, good sources of vitamins and minerals and considered other motives aside from health issues. From Pearsons's correlation analysis, it was revealed that sufficient time for meal preparation and pleasant eating and desirable life style and dietary attitudes, and a better understanding of nutrition were positively correlated with consumption of more vegetables and convenient use of vegetables. The subjects who recognized the ability of food to help prevent diseases, had a preference for vegetables and attitude to use nutritional knowledge and also considered the nutrition values of vegetables and environment friendliness. Everyday use of vegetables such as consuming a variety of different vegetables, a families favorite vegetables and variation of cooking methods had correlated positively with purchase motives. Therefore to encourage consumption of vegetables, it is important to notice three points continuously; first, practical information of nutritive values of vegetables, the contribution of vegetables in current animal protein foods centered diet and healthful functionalities. Second, the importance of regular diet and steadfast attitude and lifestyle. Finally, the quality of the market where the products are bought such as, quality control of freshness, sanitation, expression of producer and a pleasant environment to shop in.

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Development of novel microsatellite markers to analyze the genetic structure of dog populations in Taiwan

  • Lai, Fang-Yu;Lin, Yu-Chen;Ding, Shih-Torng;Chang, Chi-Sheng;Chao, Wi-Lin;Wang, Pei-Hwa
    • Animal Bioscience
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    • 제35권9호
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    • pp.1314-1326
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    • 2022
  • Objective: Alongside the rise of animal-protection awareness in Taiwan, the public has been paying more attention to dog genetic deficiencies due to inbreeding in the pet market. The goal of this study was to isolate novel microsatellite markers for monitoring the genetic structure of domestic dog populations in Taiwan. Methods: A total of 113 DNA samples from three dog breeds-beagles (BEs), bichons (BIs), and schnauzers (SCs)-were used in subsequent polymorphic tests applying the 14 novel microsatellite markers that were isolated in this study. Results: The results showed that the high level of genetic diversity observed in these novel microsatellite markers provided strong discriminatory power. The estimated probability of identity (P(ID)) and the probability of identity among sibs (P(ID)sib) for the 14 novel microsatellite markers were 1.7×10-12 and 1.6×10-5, respectively. Furthermore, the power of exclusion for the 14 novel microsatellite markers was 99.98%. The neighbor-joining trees constructed among the three breeds indicated that the 14 sets of novel microsatellite markers were sufficient to correctly cluster the BEs, BIs, and SCs. The principal coordinate analysis plot showed that the dogs could be accurately separated by these 14 loci based on different breeds; moreover, the Beagles from different sources were also distinguished. The first, the second, and the third principal coordinates could be used to explain 44.15%, 26.35%, and 19.97% of the genetic variation. Conclusion: The results of this study could enable powerful monitoring of the genetic structure of domestic dog populations in Taiwan.

Comparison of fucosterol content in algae using high-performance liquid chromatography

  • Lee, Jeong Min;Jeon, Jae Hyuk;Yim, Mi-Jin;Choi, Grace;Lee, Myeong Seok;Park, Yun Gyeong;Lee, Dae-Sung
    • Fisheries and Aquatic Sciences
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    • 제23권3호
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    • pp.9.1-9.6
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    • 2020
  • Background: Fucosterol is a compound commonly found in algae that has various biological activities. The purpose of this study was to develop a high-performance liquid chromatography (HPLC) validation method for fucosterol and to compare the fucosterol contents of 11 algal species from Ulleungdo, Korea. Method: In this study, we successfully isolated and identified fucosterol from a 70% EtOH extract of Sargassum miyabei, and subsequently conducted specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, and precision analyses for development of an HPLC validation method. Fucosterol contents were compared using the established HPLC validation conditions. Results: We successfully isolated fucosterol from a 70% EtOH extract of S. miyabei and identified it based on spectroscopic analysis. On the basis of HPLC validation using the fucosterol isolated from S. miyabei, we confirmed specificity (8.5 min), linearity (R2 = 0.9998), LOD (3.20 ㎍ mL-1), LOQ (9.77 ㎍ mL-1), accuracy (intra-day and inter-day variation, 90-110%), and precision (RSD, 1.07%). Fucosterol contents in the 11 assessed algal species ranged from 0.22 to 81.67 mg g-1, with the highest content being recorded in a 70% EtOH extract of Desmarestia tabacoides (81.67 mg g-1), followed by that of Agarum clathratum (78.70 mg g-1). Conclusions: The results indicate that 70% EtOH extracts of D. tabacoides and A. clathratum containing fucosterol with various effects can be potential alternative sources of fucosterol.

Estimation of Genetic Parameters of Body Weight Traits in Ghezel Sheep

  • Baneh, Hasan;Hafezian, Seyed Hasan;Rashidi, Amir;Gholizadeh, Mohsen;Rahimi, Ghodrat
    • Asian-Australasian Journal of Animal Sciences
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    • 제23권2호
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    • pp.149-153
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    • 2010
  • The present study was carried out to estimate genetic parameters for body weight traits in Ghezel sheep. The data set used was records of 9,221 lambs from 180 sires and 5,060 dams for birth weight (BW), 7,206 lambs from 167 sires and 4,497 dams for weaning weight (WW) and 6,112 lambs from 157 sires and 3,841 dams for 6-months weight (6 MW), which were collected from 1999 to 2007 (9-years) at Ghezel sheep Breeding Station in west Azarbaijan. Variance components and corresponding genetic parameters were obtained with univariate analyses fitting animal models using restricted maximum likelihood (REML) methods. The most suitable model for each trait was determined based on log likelihood ratio tests. Birth year, lamb gender, type of birth, age of dam and herd were significant sources of variation on BW, WW and 6 MW (p<0.01). Direct estimate of heritability for BW, WW and 6 MW was 0.24, 0.29 and 0.37, respectively. The estimate of maternal permanent environmental variance as a proportion of phenotypic variance was 0.09 and 0.05 for BW and WW, respectively. The results of this study showed that genetic progress for growth traits is possible by selection.