• Asian-Australasian Journal of Animal Sciences
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• 제17권8호
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• pp.1098-1106
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• 2004

In a split-unit design, 12 Javan rusa (Cervus timorensis russa) stags (6 castrated and 6 entire) were used to investigate seasonal (winter, spring and summer) effects on intake, digestibility of food constituents, volatile fatty acid profile, and nitrogen retention, when given lucerne (Medicago sativa) or rhodes grass (Chloris guyana) hays. Entire stags ate 9% more dry matter (DM) than castrates (p<0.05). Both castrated and entire stags exhibited seasonal changes in DM intake, these being higher (p<0.05) in winter (62.3 g/kg $W^{0.75}$) than spring (56.9 g/kg $W^{0.75}$) or summer (55.3 g/kg $W^{0.75}$). Intakes of lucerne hay (211 g protein/kg DM) were significantly higher than of rhodes grass hay (49 g protein/kg DM) in all seasons (p<0.05). Digestibilities of DM (0.58), neutral detergent fibre (0.59) and acid detergent fibre (0.47) were similar between castrates and entires. DM digestibility was higher (p<0.0001) for lucerne (0.66) than rhodes grass (0.55), and was higher (p<0.05) in winter (0.60) than spring (0.58) or summer (0.57). The ruminal acetate concentrations were higher (p<0.001) in spring than summer (78 and 73 molar % respectively). Apparent digestibility of protein was significantly less (p<0.0001) for rhodes grass (0.37) than lucerne (0.75). N retention was positive for lucerne (15.2 g/d) but negative for rhodes grass (-2.8 g/d) (p<0.0001), and was higher (p<0.001) in summer (12.0 g/d) than spring (4.3 g/d) or winter (2.4 g/d). The tropical rusa deer exhibits seasonal variations in feed intake, food constituent digestibilities, VFA profile and N retention. Castration did not alter these traits. The results do not support the view that rusa deer can thrive on low-quality pastures. The productivity and commercial exploitation of rusa deer could be optimised if they are given high-protein feed during spring and summer.

• 한국대기환경학회지
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• 제21권6호
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• pp.699-708
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• 2005

To characterize the elemental composition of fine particles in urban area, $PM_{2.5}$ was collected by a 3-stage DRUM impactor at Gwangju during spring and summer. Time and size resolved concentrations for 19 trace elements were obtained by synchrotron X-Ray fluorescence analysis. Trace elements in summer were distributed in smaller size range compared to those in spring. Almost trace element concentrations in fine particles were highly increased during the Asian dust. In spring, soil elements such as Si, K, Ca, Ti and Fe had low enrichment factors indicating the dominant influence of soil dust. However, all elements had high enrichment factors in summer implying that these elements could be emitted from the anthropogenic sources. Factor analysis was conducted with the elemental composition data in order to identify anthropogenic sources of aerosols in urban area during spring and summer. Fine particles in spring have several sources such as soil dust originating from China continental region, coal and oil combustion, biomass burning, sea salt, ferrous and nonferrous metal sources. On the other hand, fine particles in summer were influenced by road dust, gasoline vehicle as well as coal and oil combustion, sea salt, ferrous and nonferrous metal sources.

• 한국어류학회지
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• 제29권1호
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• pp.80-86
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• 2017

본 연구는 남해 중부 연안역에서 2016년 4~8월까지 자어군집구조의 월 변화를 조사하였다. 조사기간 동안 총 42종의 자어가 출현하였다. 우점종 중 멸치(E. japonicus)는 여름보다는 봄철에 우점하였고, 용서대(C. abbreviates)는 봄철에만 출현하였으며 수조기(N. albiflora)는 여름철에만 출현하였다. 자어 군집은 계절별로 4~5월 (봄)과 6~8월 (여름)의 그룹으로 유의하게 나눌 수 있었고, 여름철은 또다시 6~7월과 8월의 두개의 유의한 그룹으로 나눌 수 있었다. 2016년 8월 조사해역에서는 이상 고수온 현상이 발생하여 표면수온이 $28^{\circ}C$까지 상승하였고, 멸치와 수조기 자어의 출현량은 산란 적정수온을 넘은 수온으로 인해 급감하였다.

• 생태와환경
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• 제43권4호
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• pp.477-491
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• 2010

Benthic macroinvertebrates were collected two times from 116 sites at the $1^{st}{\sim}4^{th}$ order streams in forest areas in Gyungsang province in late spring and late summer. The sample sites belonged to slightly and moderately polluted states. When communities were classified by the Self-Organizing Map (SOM), the gradient was observed according to degree of pollution. Within clusters of slightly polluted sites, however, seasonality was further observed. Scrapers, gatherer-collectors, and filterer-collectors were abundantly observed in late spring while shredders appeared more in late summer. The number of predator species increased in late summer. Behavior types were mostly clingers in two seasons. Community compositions at the moderately polluted sites were not much differentiated in different seasons. Gatherer-collectors and burrowers were dominantly collected in both seasons.

• 환경생물
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• 제30권3호
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• pp.219-230
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• 2012

2010년 진해만의 춘계와 하계를 중심으로 환경요인 변화와 식물플랑크톤의 군집구조의 상관관계에 대한 생태학적 연구를 수행하였다. 식물플랑크톤의 생물량과 환경요인과의 상관관계를 조사하기 위해 수행한 다중상관분석과 CCA (Canonical Correspondance Analysis) 결과, 하계에 우점한 Chaetoceros spp., Skeletonema costatumlike spp., Pseudo-nitzschia delicatissima는 생물량 변화에 영향을 미치는 주요 요인을 선정할 수는 없었다. 반면, 춘계의 Cryptomonas spp.와 Pseudo-nitzschia multistriata 는 질산염과의 양(+)의 상관관계(p<0.05)가 있을 것으로 판단되었다. 하계에 나타난 식물플랑크톤과 환경요인간의 유의한 양 (+) 상관관계가 나타나지 않는 것은 강우에 의해 유입된 탁도 물질등에 의한 저층의 광합성 활성의 저하와 우점종의 구성과 생물량 차이에 의해 나타난 결과로 판단되었다. 또한 환경에 적응한 우점종의 분포특성은 진해만 광역해역을 부분적으로 구분할 수 있는 생물학적 요인으로 판단되었다. 결과적으로 식물플랑크톤과 환경요인과의 상관관계는 주요 우점종의 분포와 관련이 있었고, 특히 성층화된 하계에 우점한 식물플랑크톤 분포는 해역 구분에 중요한 인자로 활용 될 수 있었다.

• 신재생에너지
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• 제18권2호
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• pp.9-17
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• 2022

In this study, we used the Flux Balance Analysis (FBA) program to examine the behavior of hydrogen and organic acids according to seasonal changes in food wastewater collected from D city. The results showed that average hydrogen conversion rates in spring, summer, autumn, and winter were 1.06, 0.71, 1.21, and 1.13 mol H₂/mol of hexose_added, respectively, indicating a significantly lower hydrogen conversion rate in summer than in other seasons. This phenomenon is believed to occur because the carbohydrate concentration of the incoming food wastewater is low. In addition, Lactobacillus, the lactic acid-producing bacterium, was 21.3% in spring, 27.2% in summer, 17.5% in autumn, and 22.6% in winter. The most distinctive feature of the microbial community in summer was that 15.3% of the Ilyobacter was analyzed. It was confirmed that Ilyobacter, which is involved in the production of acetic acid and propionic acid, is closely associated with the tendency of increasing acetic acid and propionic acid and thus contributes to organic acid change. Clostridium, a hydrogen-producing bacterium, was 76.2%, 50.8%, 78.3%, and 74%, in spring, summer, autumn, and winter, respectively. It was confirmed that Clostridium dominates the microbial community by approximately 70% or more in all seasons except summer.

• Ocean and Polar Research
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• 제31권2호
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• pp.219-229
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• 2009

In order to establish annual variations in the marine ecosystem of the East China Sea, suspended solids (SSs) and particulate organic carbon (POC) were extensively investigated in the northern part of the East China Sea from August 2003 to April 2008. Surface SS concentrations showed large spatial variations in spring and fall, but not in summer. Surface SS concentrations in spring were lower than those in summer and fall. In summer, SSs discharged from Changjiang were mostly deposited in the coastal areas and did not reach our study area which was located about 260 km from the river mouth. High SS concentrations were observed near the bottom, which resulted from resuspension of bottom sediments by the bottom currents. Surface POC concentrations did not exhibited large seasonal variations. Phytoplankton biomass was a main factor controlling surface POC concentrations. POC/chlorophyll ratios showed large seasonal variations, with maximum numbers in summer. POC/PON ratios were higher in summer than the Redefied ratio (6.6), while they were lower in spring and fall. In summer, higher POC/chlorophyll and POC/PON ratios were probably attributed to the high phytoplankton mortality caused by nutrient depletion in surface waters.

• 한국동물위생학회지
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• 제46권3호
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• pp.227-234
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• 2023

It has been addressed that heat stress due to high atmospheric temperature during summer in Korea induces impaired release of reproductive hormones, followed by occurring abnormal ovarian cyclicity, lower pregnancy ratio, and reduced litter size. Therefore, the present study attempted to compare seasonal change (spring versus summer) of the ovarian aromatase expression, an enzyme for converting testosterone into estrogen. While serum estrogen level in summer group was significantly lower than that of spring group, testosterone was not different between groups. Consistent with estrogen level, the ovarian aromatase expression in summer at follicular phase was significantly lower than the counterpart of spring. The ovarian aromatase expression was positively related with serum estrogen level significantly (r=0.689; P=0.008) and strongly negative correlation was identified (r=-0.533; P=0.078) with atmospheric temperature. The ovarian aromatase expression was not detected in immature ovarian follicles but specifically localized in the granulosa cell layers in both seasons. However, the aromatase intensity in the granulosa cell layers was stronger in spring than summer. Because testosterone level was not different between groups, it could be concluded that the lower level of estrogen during summer might be derived by not lack of substrate but lower expression of ovarian aromatase by heat stress.

• 대한한의학원전학회지
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• 제13권1호
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• pp.184-232
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• 2000

The trend of the concept for modern medicine is gradually forwarding to preventive medicine from therapeutic medical science. One of the most remarkable characteristics of oriental medicine is that it attaches greater importance to preventive medicine scientifically. The basic theory of oriental medicine principally takes roots in Huang Di Nei Jing and it is Si Qi Tian Shen Da Lun that is deep-rooted in the principle of "growing life" grounded in theory of unity of heaven and man of oriental medicine. Therefore having translated annotation of 〈Si Qi Tian Shen Da Lun·Huang Di Nei Jing Su Wen〉 which is quoted frequently and using it for appendix and comparing each views of annotators, I would like to state the results of dissertation as below. 1. Si Qi Tian Shen of title of the paper means that it keeps our health and prevent diseases in advance to control our mind and rhythm of life to the change of Yin and Yang - that is, the grower Yin, the looser Yang - following four seasons of nature environment. 2. The summary of this dissertation is that spring means things newly sprout from old ones, things become profuse, beautiful and brilliant in the summer. Autumn stands for things is harvested and allocated evenly and finally things is closed and stored. That is, in the spring and summer. If one break this principle of growth, diseases are followed after this. Therefore an excellent physician should handle diseases before they are attacked not remedy them after outbreak of diseases. It is said that a sage governs the nation before it is put into confusion. 3. These four terms standing for each season describe definitely and realistically rural life in the agricultural environment, in other words, spouting in spring, growing in summer, harvesting in autumn, storing in winter. Going with the current of the times, they have developed to theoretical concept of getting, growth, harvest, store so that implied the principle of growth for four seasons. 4. It means in a concrete way "Yang would grow in the spring and summer and Yin would grow in autumn and winter" as follow. That is, when the day is long, things act energetically and emit the warmth of life and expand the vigor of growth. On the other hand, when the night is long, things lessen their activity to protect the warmth of life and to preserve the sprit of growth. In addition, we should be concerned about the work outward and try to concretely fulfill plan of business in spring and summer. It is in autumn and winter when we should grow Yin. It does not mean that we simply grow cold yin in our body to build Yin. But according to annotators, for example, Wang Bing stated that we need to make things be cool in spring and summer, and be warm in autumn and winter for improvement. Zhang Jie Bin noted that things should not be cold in spring and summer and not be too hot to improve in autumn and winter. Those principles theorized to unify physiological status into the principle of changing of Yang and Yin in the nature and enriched the contents. In these principles, no problems are not found logically somewhat.

• 한국대기환경학회지
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• 제12권3호
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• pp.289-296
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• 1996

Effects of crustal species on the characteristics of ambient particles were studied by applying a gas-particle equilibrium model, SCAPE, to the measurements at Kosan, Cheju Island during the spring and summer, 1994. Two cases were simulated; the measured composition was used without any modification (case 1), and the metal ion concentrations originated from crust were subtracted from the measured particle composition (case 2). Total suspended particles (TSPs) were collected by an automatic high volume tape sampler during spring period and by high volume samplers during summer period. The fine particles, PM 2.5, and gaseous volatile species were collected using a filter pack smapler during summer period. The water soluble ion concentrations were analyzed from all the particle samples. According to the simulation results, the effect of crustal elements on the chemical composition of particles is negligible for both TSP particles and PM 2.5 particles. Acidity of particles measured at Kosan, however, is affected by the change of the concentrations of crustal species, stronger effects for TSP particles than for PM 2.5 particles during summer, and stronger effects during summer than spring for TSP particle. The average pH decrease due to the absence of crustal species was about 0.10 for PM 2.5 particle during summer and 1.51 and 0.85 for TSP particles during summer spring, respectively. Water contents of PM 2.5 particles for both cases are comparable to each other. Estimated water content of TSP particles for case 2 is higher than that for case 1 by about 4 $\sim 6 \mum/m^3$ because salts of metal ions are not hygroscopic.