• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.3
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• pp.75-85
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• 2017

A method to estimate hourly temperature profiles on calm and clear nights was developed based on temporal changes of inversion height and strength. A meteorological temperature profiler (Model MTP5H, Kipp and Zonen) was installed on the rooftop of the Highland Agriculture Research Institute, located in Daegwallyeong-myeon, Pyeongchang-gun, Gangwon-do. The hourly vertical distribution of air temperature was measured up to 600 m at intervals of 50 m from May 2007 to March 2008. Temperature and relative humidity data loggers (HOBO U23 Pro v2, Onset Computer Corporation, USA) were installed in the Jungdae-ri Valley, located between Gurye-gun, Jeollanam-do and Gwangyang-si, Jeollanam-do. These loggers were used to archive measurements of weather data 1.5 m above the surface from October 3, 2014, to November 23, 2015. The inversion strength was determined using the difference between the temperature at the inversion height, which is the highest temperature in the profile, and the temperature at 100 m from the surface. Empirical equations for the changes of inversion height and strength were derived to express the development of temperature inversion on calm and clear nights. To estimate air temperature near the ground on a slope exposed to crops, the equation's parameters were modified using temperature distribution of the mountain slope obtained from the data loggers. Estimated hourly temperatures using the method were compared with observed temperatures at 19 weather sites located within three watersheds in the southern Jiri-mountain in 2015. The mean error (ME) and root mean square error (RMSE) of the hourly temperatures were $-0.69^{\circ}C$ and $1.61^{\circ}C$, respectively. Hourly temperatures were often underestimated from 2000 to 0100 LST the next day. When temperatures were estimated at 0600 LST using the existing model, ME and RMSE were $-0.86^{\circ}C$ and $1.72^{\circ}C$, respectively. The method proposed in this study resulted in a smaller error, e.g., ME of $-0.12^{\circ}C$ and RMSE of $1.34^{\circ}C$. The method could be improved further taking into account various weather conditions, which could reduce the estimation error.

• Journal of Life Science
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• v.20 no.7
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• pp.1019-1026
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• 2010

Obesity and being overweight are strongly associated with the development of metabolic disease such as diabetes, hypertension, dyslipidemia. High-fat diet (HFD) is one of the most important factors which cause obesity. In this study, C57BL/6 mice were treated with a HFD for 22 weeks in order to induce obesity and hyperglycemia. Twenty-two weeks later, body weight and plasma glucose level of the HFD group were significantly increased, compared with the normal diet (ND) group. Intra-peritoneal glucose tolerance test (IPGTT) showed glucose intolerance in the HFD group compared with the ND group. These results confirmed that a HFD induced obesity and hyperglycemia in C57BL/6 mice. Plasma levels of triglyceride (TG) and total cholesterol (TC) were increased in the HFD group compared with the ND group. Hepatic levels of TG and TC were also increased by a HFD. To investigate the alteration of lipid metabolism in liver, proteins which are related to lipid metabolism were observed. Among lipid synthesis related enzymes, fatty acid synthase (FAS) and glycerol phosphate acyl transferase (GPAT) were significantly increased in the HFD group. Apolipoprotein B (apoB) and microsomal triglyceride transport protein (MTP), which are related to lipid transport, were significantly increased in the HFD group. Interestingly, protein level and phosphorylation of AMP-activated protein kinase (AMPK), which is known as a metabolic regulator, were significantly increased in the HFD group compared with the ND group. In the present study we suggest that HFD may physiologically increase the proteins which are related with lipid synthesis and lipid transport, but that HFD may paradoxically induce the activation of AMPK.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.4
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• pp.590-595
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• 2008

The aim of our study was to research the effect of overfeeding on plasma parameters and mRNA expression of genes associated with hepatic lipogenesis in the Sichuan white goose and Landes goose. Fifty-four male Landes geese and 57 male Sichuan white geese were hatched on the same day under the same feeding conditions. After overfeeding for 14 days, (1) extrahepatic adipose tissues grew greatly in the Sichuan white geese, while more lipid accumulated in liver tissue in the Landes geese. (2) Sichuan white geese had a higher plasma concentration of triacylglycerols (TG), lipoproteins and insulin than the Landes geese. However, the Landes geese exhibited higher increase of plasma concentrations of TG, lipoproteins and insulin, with greater decrease of the diacylglycerol acyltransferase 2 (DGAT2) activity and DGAT2 mRNA level and a smller decrease of plasma glucose concentration. In addition, the mRNA level of MTP and LPL in liver was down- and up- regulated by overfeeding, respectively. (3) The correlations between the activity of LPL and the proportions of subcutaneous adipose tissue, abdominal adipose tissue, and liver weight, and the plasma concentration of VLDL were different in the two breeds. (4) The proportion of fatty liver weight was positively correlated to plasma concentrations of VLDL and TG in the overfed Sichuan white geese. Such a relationship did not exist in the Landes geese. (5) The activity of DGAT2 and its mRNA abundance in liver had significant negative correlations with the TG content in liver lipid and plasma insulin level in the Landes geese, while in the Sichuan white geese they had negative correlation (p>0.05) with TG concentration in liver lipid and had significant positive correlation with VLDL and TG concentrations in plasma.