Earticle

Growth of fish is controlled by various environmental factors, including water temperature (WT). WT is also a major factor that affects the eating behavior of fish. In this study, we studied the relationship between WT and expression profiles of factors involved in appetite regulation and digestion in red spotted grouper. Fish were divided into three groups with 30 fish per group and reared for 2 weeks in a recirculating system at three different WT (natural WT, 20 °C, and 25 °C). After 2 weeks, they were sacrificed immediately after food intake (+ 0 h), 3 h after (+ 3 h), 6 h after (+ 6 h), and 3 h before being fed the next day (− 3 h). Fish samples were obtained for analysis of mRNA expression levels of cholecystokinin (CCK), leptin A (LepA), leptin B (LepB), and neuropeptide Y (NPY) in the brain, liver, and intestine. Expression of CCK and NPY mRNA was significantly higher at 25 °C compared to that at natural WT and 20 °C, but no difference was observed for leptin. This suggests that the red spotted grouper shows characteristics typical of subtropical fish and has higher levels of feeding and digestion when reared at 25 °C water temperature condition.

본 연구는 지구 온난화로 인해 상승하고 있는 수온이 계곡산개구리에게 미치는 영향을 알아보기 위해 진행되었다. 이 를 위해 서울에 위치한 수락산 일대(37°40'55.86"N, 127°05'19.99"E)에서 계곡산개구리 난괴를 채집하였다. 총 9개 의 난괴를 채집하였으며 3개의 그룹으로 나누어 각각의 인큐베이터에 LT (5 ± 2℃), MT (10 ± 2℃), HT (13 ± 2℃)로 온도를 달리하여 사육하였다. 각각의 실험군 LT (5 ± 2℃), MT (10 ± 2℃), HT (13 ± 2℃)은 모든 유생이 부화 할 때까지 실험이 진행되었으며 각각의 난괴에서 부화한 개체의 부화율과 부화일수, 개체의 크기를 측정하였고 통계분석을 통해 온도가 유생의 발달에 미치는 영향을 분석 하였다. 유생의 부화율은 MT (10 ± 2℃)일 때 95.6%로 가장 높았고 HT (13 ± 2℃)일 때 82.6%, LT (5 ± 2℃)일 때 82.2%로 비슷한 수치가 나왔다. 유생의 부화일수는 HT (13 ± 2℃)그룹이 10일로 가장 짧았으며, MT (10 ± 2℃)그룹은 14일, LT (5 ± 2℃) 그룹은 23일이었다. 실험 결과, 부화 개체의 크기는 MT (10 ± 2℃)일 때 7.62 ± 0.11㎜, HT (13 ± 2℃)일 때 7.19 ± 0.15㎜, LT (5 ± 2℃)일 때 6.82 ± 0.10㎜ 순으로 작아졌다(ANOVA, p-value =0.00000). 본 연구를 통해 개구리의 성장과 부화에는 최적온도가 존재할 것이라 예상되었고, 지구온난화로 인한 온도의 변화는 계곡산 개구리에 부화와 성장에 영향을 미칠 수 있음이 확인되었다. 본 연구를 통해 도출한 결과를 바탕으로 더 나아가 온도 구배 상황에서 계곡산개구리 성체까지 의 변태율과 크기에 미치는 영향에 대한 실험을 진행한다면 기후 변화에 적응하는 개체군에 대한 이해뿐만이 아니라 추후 멸종위기종 보존대책 등에 대한 연구에 큰 도움을 줄 것으로 기대된다.

This study was executed to know the effect of three differently controlled temperature conditions on Huanren brown frog (Rana huanrensis )’s growth in 2013. We've collected nine Huanren brown frog egg's sacs on Mt. Surak (37°40'55.86"N, 127°05'19.99"E) in Seoul. We put those nine egg sacs in the controlled growth chambers under low temperature (LT, 5 ± 2℃), medium temperature (MT, 10 ± 2℃), and high temperature (HT, 13 ± 2℃) conditions with three egg sacs, respectively. We measured the eggs' hatching rate, their hatching periods, and the size of the hatched individuals. The hatching rate was higher in MT (95.6%) and the rates of the other treatments were relatively lower but very similar such as LT (82.2%) and HT (82.6%). The three hatching periods were 10 days at HT, 14 days at MT and 23 days at LT. The body sizes of the hatched individuals were biggest at MT (7.62 ± 0.11㎜), smallest at LT (6.82 ± 0.10㎜) and medium at HT (7.19 ± 0.15㎜) (P-value ≤0.0001). From our results, we found that the various water temperatures could be very effective to Huanren brown frog eggs’ hatch and growth including their body sizes. We suggest if we study more about the growth of Huanren brown adult frogs under similar temperature conditions for a long term period, it must be very helpful for conservation study about metamorphosis rate and size of adult frog as well as we could understand about the amphibians who are adapting to the climate change.

수환경에는 다양한 화학물질이 존재하여 수서생물에 대한 부정적 영향을 야기한다. 최근 이슈가 되고 있는 기후변화는 기온의 상승에 의해 지구전반에 걸쳐 생태계에 어려움을 발생시키고 있으며 우리나라의 경우도 예외라고 할 수 없다. 기 온의 상승에 의해 영향을 받는 수온의 변화가 수환경에 서식하는 생물의 생육에 미치는 영향이 보고되기도 하였다. 본 연 구에서는 수온의 변화가 환경중에 존재하는 화학물질의 독성영향에 미치는 변화를 관찰하였으며 이러한 변화가 분자적 수준의 지표에서 확인될 수 있는지 평가하였다. 오염물질이 존재하지 않는 환경에서 수온의 상승은 대표적인 시험종인 물벼룩의 번식에 영향을 미칠수 있음이 확인되었으며 이러한 영향은 분자적수준의 지표인 Vitellogenin, DMRT 및 Cuticle 의 gene 발현에서도 관찰되었다. 오염물질로서 나노물질을 이용한 독성평가에서는 96시간의 급성노출에서 물벼 룩의 적응온도와 노출온도의 차이에 따라 영향정도가 크게 차이나지는 않았지만 만성생식영향에서는 비노출에서는 오히 려 산자수가 감소한 반면 노출군에서는 산자수등이 크게 증가하여 오염물질의 노출과 수온의 변화가 상승작용을 하는 것으로 추정된다.

Water temperature, which is affected by climate change, could have influence on the growth of organisms in the aquatic environment. Various chemicals discharged from industry and human activities are present in the aquatic environment, causing negative effects on aquatic life. In this study, changes in water temperature on the toxic effects of chemical substances in the environment were observed, and whether these changes could be confirmed at the molecular level was evaluated. It was confirmed that an increase in water temperature in an environment free of contaminants could affect the reproduction of Daphnia magna, a representative test species. Also when D. magna was acclimated in higher temperature than normal test condition gene expressions of vitellogenin, DMRT and cuticle was affected. In the toxicity evaluation using nano-materials as pollutants, the degree of influence did not differ significantly depending on the difference between the adaptive temperature and the exposure temperature of D. magna in the acute exposure for 96 hours. It is estimated that exposure to pollutants and changes in water temperature have a synergistic effect.

To understand the temporal dynamics of stream water temperature for hydrological aspect, we examined steam water temperature, air temperature, runoff, and precipitation in 23.4 ha a natural forested catchment, Gangwon-do, Korea. The data was collected during limited period (i.e., spring, summer, and fall except for winter) from 2017 to 2018 year. For measurement of stream water temperature and runoff, intakes of sampler was located with parshall flumes in the gauging station of catchment. Both of precipitation and air temperature were collected using HOBO tipping-bucket rain gauge. Stream water temperature was correlated with air temperature and tended to be lower than air temperature. Correlation analysis was conducted by stream water temperature with air temperature, runoff, and precitation during each seasonal changes. Stream water temperature was correlated with each different parameter by seasonal character. Regression analysis could be developed due to contribution of air temperature with runoff and precipitation to respond stream water temperature. Therefore, method using parameters of temporal variation could be recommended for predicting stream water temperature with each season. This study also indicated the changes in stream water temperature based on hydrological connectives and/or processes with seasonal character within a natural forested catchment.

As a preliminary investigation into the effects of environmental factors on gonadal development using adaptive physiological characteristics, we examined the involvement of photoperiod and water temperature in the ovarian development of the redspotted grouper, Epinephelus akaara. During October 2014 (non-breeding season), the photoperiod and water temperature were adjusted to 12L:12D and 18°C respectively. Every 3 weeks, daylight was increased as follows a 13L:11D and 14L:10D in the photo-thermal treatment group, and the control group was maintained under natural conditions. After 9 weeks, water temperature was increased to 23°C in the photo-thermal treatment group. In photo-thermal treatment group, GSI increased significantly after 9 weeks (1.36 ± 0.19) and 12 weeks (3.31 ± 0.20) compared with the control group. At 12 weeks after photo-thermal treatment, all fishes matured into  ovaries containing late vitellogenic oocytes. The expression of FSHβ and LHβ mRNAs also increased significantly. However, in the control group, the ovarian development was maintained at an immature stage. Based on these results, we demonstrate that exposure to long photoperiod and high water temperature can induce the sexual maturation of immature red-spotted grouper during the non-breeding season.

하수슬러지는 탈수과정을 거쳐도 수분 함유량이 높기 때문에 이를 연료 등 에너지로 활용할 경우 약 80%인 수분함량 을 10% 이하로 낮추어야 한다. 하수슬러지를 연료로 이용하거나 수분을 저감할 경우 Bio-drying에 의한 발효·건조 시스 템을 도입하고 있으며, Bio-drying 시스템은 일반적으로 호기성 미생물이 하수슬러지 내 유기물을 분해시킬 때 발생하는 열에 의해 건조하는 시스템으로서 발효조 온도 변화와 수분 저감의 관련성은 매우 중요하다고 판단되므로 이의 상관관 계를 규명하고자 하였다. Bio-drying 시스템에 의한 하수슬러지 수분저감은 발효조의 교반 횟수와 70oC 이상의 고온 유 지가 수분저감에 가장 영향이 미치는 것으로 나타났으며, 공기는 390~600 mL/kg·min으로 공급한 경우 과다 공급으로 인 한 온도의 저하 현상이 나타났다. 교반 횟수를 1~5회 많이 한 실험의 경우 수분저감 효과가 14.5% 및 15.5%로서 평균 저감률 12.7%보다 훨씬 더 저감률이 크게 나타났다.

Since sewage sludge has a high moisture content even after dehydration, when used as energy such as fuel, the moisture content of sewage sludge must be reduced to 10% or less. In the case of using sewage sludge as fuel or reducing moisture, a fermentation and drying system by Bio-drying is introduced, and the Bio-drying system is generally dried by heat generated when aerobic microorganisms decompose organic matter in the sewage sludge, and the correlation between the temperature change and the water reduction of the fermentation tank is determined to be very important. The reduction of sewage sludge moisture by the bio-drying system was found to be most affected by the number of stirrings in the fermentation tank and the maintenance of high temperatures of 70oC or higher, and the reduction of temperature caused by excessive supply of air at 390 to 600mL/kg/min was found. In the case of experiments with one to five times more stirring times, the moisture reduction effect was 14.5% and 15.5%, which showed much greater reduction rate than the average reduction rate of 12.7%.

Oxidative stress (OS) plays an important role in many diseases, and its excessive increase affects human health. Although the antioxidant effect of sea salt can be strengthened through special processing, it is scarcely studied. This study confirmed the antioxidative effect of high-temperature roasted mineral salt (HtRMS) produced through repeated roasting of sea salt at high temperature in a ceramic vessel. The dissolved HtRMS exhibited properties such as high alkalinity, rich mineral content, and a high concentration of hydrogen (H2). To detect the antioxidative effect of HtRMS, OS was induced in RAW 264.7 murine macrophage cells with hydrogen peroxide (H2O2) and lipopolysaccharide (LPS), and then treated with HtRMS solution at different concentrations (0.1, 1, and 10%). Cell viability, reactive oxygen species (ROS), nitric oxide (NO), and antioxidant enzymes such as catalase (CAT) and glutathione peroxidase (GPx), Ca2+, and mitogen-activated protein kinase (MAPK) pathway-related proteins (p-p38, p-JNK, and p-ERK) were measured. OS was significantly induced by treatment with H2O2 and LPS (p < 0.001). After treatment with HtRMS, cell viability and GPx activities significantly increased and ROS, NO, Ca2+, and CAT significantly decreased in a concentration-dependent manner compared to H2O2 and LPS-only groups, which was not observed in tap water (TW)-treated groups. Similarly, p-p38, p-JNK, and p-ERK levels significantly decreased in a concentration-dependent manner in HtRMS groups compared to both H2O2 and LPS-only groups; however, those in TW groups did not exhibit significant differences compared to H2O2 and LPS-only groups. In conclusion, our results suggest that HtRMS may have antioxidant potential by regulating the MAPK signaling pathway.

We propose a new method to remove salts that have permeated into excavated metal objects. This method cleans the excavated metal objects by using high temperature, high pressure deoxvgenated water containing inhibitors for corrosion of metals. The method greatly reduces the washing time compared with previous methods. Waste water from the method does not need treatment, nor do chemicals need to be removed from the metal objects. Furthermore, this method is applicable to some kind of metals(for example iron objects, bronze objects). We measured quantitatively the soluble salts dissolved from actual metal objects and found that there was a large difference between soluble chloride ions and sulfate ions.

최근 몇 년간 하천에서의 부영양화가 심해짐에 따라 녹조가 발생하며 수질에 큰 영향을 미치고 있다. 우리나라 수자원 의 대부분은 하천에서 비롯되기 때문에 오염을 방지하기 위해 원인을 사전에 예측하고 예방하는 것이 중요하다. 현재 하 천에서 Chl-a의 수를 파악할 수 있는 공정은 복잡하고 시간이 오래 걸리는 단점을 가지고 있다. 이러한 문제점을 해결하 기 위해 본 연구에서는 온도와 DO에 따른 Chl-a의 성장률을 비교하고 관계식을 개발해 UV 흡광도 값만으로 Chl-a의 수 를 예측할 수 있도록 하였다. 관계식을 개발하기 위해 실험실 내부의 항온수조에서 실험을 진행하였으며 온도와 DO 조 건은 2016년 수질 자료를 참고해 설정하였다. 배양 실험을 통해 Chl-a는 DO 조건에 상관없이 27oC에서 모두 원활한 성 장을 보이는 것을 알 수 있었다. 또한, 관계식을 통해 복잡한 실험을 거치지 않고 DO, 온도, UV 흡광도 값을 예측할 수 있었다.

As the eutrophication in rivers becomes serious, the green algae bloom has also a great influence on the water quality in recent years. In South Korea, since most of the water resources come from rivers, it is important to predict and prevent the causative phenomena beforehand in order to prevent contamination of water resources. In order to know the number of Chl-a in the current stream, the process is complex and time-consuming. To solve these problems, this study compared the growth rate of Chl-a by temperature and DO and developed a formula that can predict the number of Chl-a by using the UV absorbance value. Culturing for developing formula were conducted inside a constant temperature chamber, and the temperature and DO conditions were determined by referring to river water quality of 2016. Culturing showed that Chl-a grew equally well at a temperature of 27oC under all DO conditions. Also, by developing formula that can predict the number of Chl-a using DO, temperature and UV absorbance values, so that can know the number of Chl-a without doing complex experiment.

Purpose: To investigate the effects of a warm water-filled bag on body temperature, Oxygen demand, respiratory rate and blood sugar in high risk neonates. Method: The infants were assigned to two groups, 16 in the experimental and 20 in the control group. Infants in the experimental group was received 40～42℃ warm water-filled bag therapy for 2 hours under radiant warmers. Infants in the control group were placed under the same kind of radiant warmers but without the warm water-filled bag. The following were measured every 30 minutes: rectal temperature, O₂ demand (FiO₂), and respiratory rate. Blood sugar was measured hourly. Result: Body temperatures increased significantly in the experimental group (P=0.0138), and there was a difference according to time (P=0.0001). Significant difference were found between the two groups for FiO₂ (P=0.0180). There was no difference in respiratory rates between the two groups and rates according to time for the experimental group were also not significant (P=0.3569). No significant difference between two groups was found for blood sugar(P=0.2152), but there was a significant difference according to the times (P=0.0001). Conclusion: This results of this study indicate that a warm-filled bag is an effective means of resorting body temperature and reducing O2 demand in high risk neonates.

Hepatoprotective and antioxidant activities of Acer mono and A. okamotoanum were compared after being extracted by low temperature and high pressure (LTHP) at 20 MPa and 60℃ for 15 minutes. Extraction yield of both A. mono and A. okamotoanum was increased about 40~43% by this extraction process. On scavenging activities, the bark of A. okamotoanum from this extraction process showed the highest activity as about 97%. This value was higher than that from conventional water extraction and A. mono extracts. Both of A. mono and A. okamotoanum showed high ability on nitrite scavenging, but decreasing tendency according to increasing of pH. On SOD-like test, A. okamotoanum had the highest activity as 46.28% at 1.0 ㎎/㎖ concentration. A. okamotoanum extracted by LTHP also showed the highest activity as 197.38% in adding 1.0 ㎎/㎖ concentration. Generally, the extracts from low temperature and high pressure extraction process are higher hepatoprotective and antioxidant activities than that from conventional water extraction. It can conclude that the bark of A. okamotoanum has better biological activities than other parts of A. mono.

이 연구는 음나무의 생장에 대한 생리 생태적 특성을 측정하여 조림목의 적지환경을 구명하고자 하는 일련의 연구이다. 본 측정에서는 에서는 잎의 기공증산속도의 일 변화,수분이용효율의 일변화,수분포텐셜의 일변화, 그리고 세포간극의 CO2 농도 일변화 등을 측정,고찰하였다. 그 결과를 요약하면 다음과 같다. 1) 기공증산속도의 일변화는 오전 10시경이 가장 높았으며, 16시를 기점으로 기공증산속도는 빠르게 감소하였다. 2) 수분이용효율의 일변화는 오전8시경에 최대치를 보였고,그 후 수분포텐셜의 감소와 함께 정오까지 빠르게 감소하였다가 회복한 후 17시 이후부터는 급격한 감소를 보였다. 3) 세포간극의 CO2 농도(Ci/Ca 비율)의 일변화는 오전9시까지 빠르게 감소하였고,그 후16시까지는 큰 변화 없이 안정한 값을 유지하였으며, 16시 이후부터는 다시 빠르게 증가하였다. Ci/Ca 비율의 일변화는 수분포텐셜의 일변화와 거의 유사한 경향을 보였다. 결과적으로 산지에 식재된 음나무 잎의 기공증산,수분이용효율,수분포텐셜이 높은 오전에 가장 증가하고,오후부터 급격한 감소를 나타냈다.

This study was purposed to elucidate the best optimum sites by ecophysiological response measurements of Kalopanax pictus samplings of plantation. The diurnal changes of the stomatal transpiration, water use efficiency, water potential, and intercellullar CO2 concentration of leaves were measured by the portable IR CO2 analyzer. The results obtained are summarized as follows. 1) The daily stomatal transpiration rate was highest at 10:00 a.m. After 16:00, the stomatal transpiration rate rapidly decreased. 2) The daily water use efficiency was maximum at 8:00 a.m., and then rapidly decreased until midday with decreasing water potential. 3) The daily Ci/Ca ratio rapidly decreased until 9:00 a.m., and then showed a stable value until 16:00, and then rapidly increased. The daily intercellullar CO2 concentration (Ci/Ca ratio) showed the same tendency as water potential changes. Consequently, stomatal transpiration and water use efficiency was increased with high water potential of leaves at am, and then remarkably decreased with low water potential at pm.

수온은 하천의 물리적·생물학적 과정에 지대한 영향을 미치는 인자로서 어류를 비롯한 수생생태계에 대한 제약조건으 로 작용한다. 기후변화로 인하여 실질적인 환경의 변화가 나타나고 있는 현실에서 수온 변화에 대한 예측은 필수적이 라 하겠다. 본 연구의 목적은 자연 소하천을 대상으로 하천 수온을 모의 및 그 효율을 비교 분석하고, 향후 기후변화로 인한 하천 수온의 변동을 고찰하는 것이다. 이를 위하여 본 연구에서는 캐나다 동북부의 Fourchue 강을 대상으로 하여 2011년부터 2014년까지의 하천수온을 측정하고 결정론적, 확률론적, 비선형 수온모형을 적용하여 각각의 방법론에 따 른 효율성을 비교 분석하여 미래 수온 모의를 위한 모형으로 결정론적 모형인 CEQUEAU 모형을 선정하였다. 또한, 선정된 모형을 기반으로 하여 CMIP5 기후모형과 RCP 2.6, 4.5, 8.5 기후변화 시나리오를 이용하여 해당 소하천 유역 의 미래 수온 변동성을 예측하고 분석하였다. 연구결과, Fourchue 강의 수온은 6월 중 평균 수온은 0.2 ~ 0.7˚C가 상 승하고, 9월은 0.2 ~ 1.1˚C가 감소하는 것으로 나타나 실질적인 수온환경의 변화가 발생하는 것으로 나타나서 이에 대한 주의가 요구된다. 또한, 해당 수역에 서식하고 있는 연어류의 치사상한수온을 넘는 경우도 발생하여 이에 대한 대책이 시급한 것으로 판단된다.

Water temperature affects physical and biological processes in ecologies on river system and is important conditions for growth rate and spawning of fish species. The objective of this study is to compare models for water temperature during the summer season for the Fourchue River (St-Alexandre-de-Kamouraska, Quebec, Canada). For this, three different models, which are CEQUEAU, Auto-regressive Moving Average with eXogenous input and Nonlinear Autoregressive with eXogenous input, were applied and compared. Also, future water temperature in the Fourchue river were simulated and analyzed its result based on the CMIP5 climate models, RCP 2.6, 4.5, 8.5 climate change scenarios. As the result of the study, the water temperature in the Fourchue river are actually changed and median water temperature will increase 0.2 ~ 0.7 ℃ in June and could decrease by 0.2~1.1℃ in September. Also, the UILT (24.9℃) for brook trout are also likely to occurred for several days.