• Journal of The Geomorphological Association of Korea
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• v.20 no.3
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• pp.95-107
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• 2013

In order to examine the temperature regime responsible for periglacial processes, air and ground temperatures were monitored from October 2010 to May 2011 at a subalpine bare patch (1,710m asl) of Mt. Halla. Four thermistor sensor probes were installed at 55 cm above a ground surface and depths of 2 cm, 10 cm, and 20 cm, respectively. A mean air temperature is $-0.1^{\circ}C$, while mean ground temperatures are $1.8^{\circ}C$ at 2 cm, $2.6^{\circ}C$ at 10 cm and $3.2^{\circ}C$ at 20 cm deep. A mean monthly ground temperature at 2 cm deep demonstrates below $0^{\circ}C$ successively from January to March, while those at 10 cm and 20 cm deep show no sub-zero temperature. A total of 72 freeze-thaw cycle was observed in air temperature. However, the numbers in ground temperature reduced into 17 at 2 cm, 8 at 10 cm, and 3 at 20 cm deep. The cycles of air temperature and ground temperature at 2 cm deep mostly fluctuated diurnally, while those of ground temperature at 10 cm and 20 cm deep exhibited a several-daily oscillation. Snow cover over 55 cm high remained from January to early April, and it seemed to disappear completely on April 16. A seasonal frost of at least 2 cm thick was formed on late December and the isotherm of $0^{\circ}C$ descended slowly into 10 cm deep on late March to early April due to the insulating snow cover. It showed the maximum freezing depth of 20 cm on April 7 to 14 and then thawed rapidly so that the frozen ground did not longer after April 17. Periglacial processes are predominant during a freezing period than a thawing period when the ground surface is still covered with snow. The periglacial mass movement in the subalpine zone of Mt. Halla is mainly generated by frost creep in terms of the occurrence depth of diurnal freeze-thaw cycle and the maximum freezing depth of ground.

• Journal of Pharmacopuncture
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• v.12 no.3
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• pp.61-72
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• 2009

Objectives : This experimental study was performed to investigate the safety and efficacy of Bovis Calculus pharmacopuncture solution manufactured with freezing dryness method to use eye drop. To identify the use of it as eye drop, the eye irritation test of rabbits and the antibacterial test of Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, and Candida albicans were performed. Methods : 1. The eye irritation test of this material was performed according to the Regulation of Korea Food & Drug Administration(2005. 10. 21, KFDA 2005-60). After Bovis Calculus pharmacopuncture solution was administered in the left eye of the rabbits, eye irritation of the cornea, iris and conjunctiva was observed at 1, 2, 3, 4 & 7day. 2. After administering Bovis Calculus pharmacopuncture solution on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) which cause Keratitis, MIC(Minimum Inhibition Concentration) and the size of inhibition zone were measured. Anti-bacterial potency was also measured using the size of inhibition zone. Results : 1. After Bovis Calculus pharmacopuncture solution was administered in the left eye of the rabbits, it was found that none of nine rabbits have abnormal signs and weight changes. 2. After Bovis Calculus pharmacopuncture solution was medicated in the left eye of the rabbits, no eye irritation of the cornea, iris and conjunctiva was observed at 1, 2, 3, 4 & 7day. 3. There was no response to MIC on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) after Bovis Calculus pharmacopuncture solution was medicated. Conclusions : The present study suggests that Bovis Calculus pharmacopuncture solution is a nontoxic and non-irritant medicine, which does not cause eye irritation in rabbits, but dosen't have antibacterial effects on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans) which cause Keratitis. These study result recommends that more research on other herbal medicines of eye drop for Keratitis are required.

• Journal of The Geomorphological Association of Korea
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• v.18 no.3
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• pp.21-36
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• 2011

Rock Weathering is a basic of geomorphological evolution as a preparation of materials. Of those, frost shattering has traditionally been considered as the operative process causing rock breakdown in cold regions as well as temperate zone. Each Granite(fresh rock, semi-weathered), Gneiss, Limestone, Dolomite was prepared slab specimens in ten, repeated freeze-thaw cycles of 180 under the -25℃~+30℃, and the changes was observed in physical properties and weathering aspect. Rock shattering was more active in waterlogging conditions rather than atmospheric and soil conditions. Limestone and Dolomite that high porosity are most severely crushed. Gneiss, regardless surface of the crack, joint, fissure and has a lowest rock strength(SHV), was even though no physical changes and their weathering product do not generate, has a very high resistance to weathering.

• Korean Journal of Agricultural and Forest Meteorology
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• v.10 no.4
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• pp.121-131
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• 2008

This study was conducted to delineate temporal and spatial patterns of potential risk of cold injury by combining the short-term cold hardiness of Campbell Early grapevine and the IPCC projected climate winter season minimum temperature at a landscape scale. Gridded data sets of daily maximum and minimum temperature with a 270m cell spacing ("High Definition Digital Temperature Map", HD-DTM) were prepared for the current climatological normal year (1971-2000) based on observations at the 56 Korea Meteorological Administration (KMA) stations using a geospatial interpolation scheme for correcting land surface effects (e.g., land use, topography, and elevation). The same procedure was applied to the official temperature projection dataset covering South Korea (under the auspices of the IPCC-SRES A2 and A1B scenarios) for 2071-2100. The dormancy depth model was run with the gridded datasets to estimate the geographical pattern of any changes in the short-term cold hardiness of Campbell Early across South Korea for the current and future normal years (1971-2000 and 2071-2100). We combined this result with the projected mean annual minimum temperature for each period to obtain the potential risk of cold injury. Results showed that both the land areas with the normal cold-hardiness (-150 and below for dormancy depth) and those with the sub-threshold temperature for freezing damage ($-15^{\circ}C$ and below) will decrease in 2071-2100, reducing the freezing risk. Although more land area will encounter less risk in the future, the land area with higher risk (>70%) will expand from 14% at the current normal year to 23 (A1B) ${\sim}5%$ (A2) in the future. Our method can be applied to other deciduous fruit trees for delineating geographical shift of cold-hardiness zone under the projected climate change in the future, thereby providing valuable information for adaptation strategy in fruit industry.

• Journal of the Korean Geotechnical Society
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• v.27 no.11
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• pp.71-81
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• 2011

Adfreeze bond strength is a primary design parameter, which determines bearing capacity of pile foundation in frozen ground. It is reported that adfreeze bond strength is influenced by various affecting factors like freezing temperature, confining pressure, characteristics of pile surface, soil type, etc. However, several limited researches have been performed to obtain adfreeze bond strength, for past studies considered only few affecting factors such as freezing temperature and type of pile structures. Therefore, there exists a limitation of estimating the design parameter of pile foundation with various factors in frozen ground. In this study, artificial neural network algorithm was involved to predict adfreeze bond strength with various affecting factors. From past five studies, 137 data for various experimental conditions were collected. It was divided by 100 training data and 37 testing data in random manner. Based on the analysis result, it was found that it is necessary to consider various affecting factors for the prediction of adfreeze bond strength and the prediction with artificial neural network algorithm provides enough reliability. In addition, the result of parametric study showed that temperature and pile type are primary affecting factors for adfreeze bond strength. And it was also shown that vertical stress influences only certain temperature zone, and various soil types and loading speeds might cause the change of evolution trend for adfreeze bond strength.

• Toxicological Research
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• v.32 no.2
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• pp.123-132
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• 2016

The impact of mobile phone (MP) radiation on the brain is of specific interest to the scientific community and warrants investigations, as MP is held close to the head. Studies on humans and rodents revealed hazards MP radiation associated such as brain tumors, impairment in cognition, hearing etc. Melatonin (MT) is an important modulator of CNS functioning and is a neural antioxidant hormone. Zebrafish has emerged as a popular model organism for CNS studies. Herein, we evaluated the impact of GSM900MP (GSM900MP) radiation exposure daily for 1 hr for 14 days with the SAR of 1.34W/Kg on neurobehavioral and oxidative stress parameters in zebrafish. Our study revealed that, GSM900MP radiation exposure, significantly decreased time spent near social stimulus zone and increased total distance travelled, in social interaction test. In the novel tank dive test, the GSM900MP radiation exposure elicited anxiety as revealed by significantly increased time spent in bottom half; freezing bouts and duration and decreased distance travelled, average velocity, and number of entries to upper half of the tank. Exposed zebrafish spent less time in the novel arm of the Y-Maze, corroborating significant impairment in learning as compared to the control group. Exposure decreased superoxide dismutase (SOD), catalase (CAT) activities whereas, increased levels of reduced glutathione (GSH) and lipid peroxidation (LPO) was encountered showing compromised antioxidant defense. Treatment with MT significantly reversed the above neurobehavioral and oxidative derangements induced by GSM900MP radiation exposure. This study traced GSM900MP radiation exposure induced neurobehavioral aberrations and alterations in brain oxidative status. Furthermore, MT proved to be a promising therapeutic candidate in ameliorating such outcomes in zebrafish.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.5
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• pp.525-538
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• 2018

Post-traumatic stress disorder (PTSD) is a trauma-induced psychiatric disorder characterized by impaired fear extermination, hyperarousal, and anxiety that may involve the release of monoamines in the fear circuit. The reported pharmacological properties of tetramethylpyrazine (TMP) include anti-cancer, anti-diabetic, anti-atherosclerotic, and neuropsychiatric activities. However, the anxiolytic-like effects of TMP and its mechanism of action in PTSD are unclear. This study measured several anxiety-related behavioral responses to examine the effects of TMP on symptoms of anxiety in rats after single prolonged stress (SPS) exposure by reversing the serotonin (5-HT) and hypothalamic-pituitary-adrenal (HPA) axis dysfunction. Rats were given TMP (10, 20, or 40 mg/kg, i.p.) for 14 days after SPS exposure. Administration of TMP significantly reduced grooming behavior, increased the time spent and number of visits to the open arm in the elevated plus maze test, and significantly increased the number of central zone crossings in the open field test. TMP administration significantly reduced the freezing response to contextual fear conditioning and significantly restored the neurochemical abnormalities and the SPS-induced decrease in 5-HT tissue levels in the prefrontal cortex and hippocampus. The increased 5-HT concentration during TMP treatment might be partially attribute to the tryptophan and 5-hydroxyindoleacetic acid mRNA level expression in the hippocampus of rats with PTSD. These findings support a role for reducing the altered serotonergic transmission in rats with PTSD. TMP simultaneously attenuated the HPA axis dysfunction. Therefore, TMP may be useful for developing an agent for treating psychiatric disorders, such those observed in patients with PTSD.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.1
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• pp.49-60
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• 2004

Northern Gyeonggi Province(NGP), consisting of 3 counties, is the northernmost region in South Korea adjacent to the de-militarized zone with North Korea. To supplement insufficient spatial coverage of official climate data and climate atlases based on those data, high-resolution digital climate models(DCM) were prepared to support weather- related activities of residents in NGP Monthly climate data from 51 synoptic stations across both North and South Korea were collected for 1981-2000. A digital elevation model(DEM) for this region with 30m cell spacing was used with the climate data for spatially interpolating daily maximum and minimum temperatures, solar irradiance, and precipitation based on relevant topoclimatological models. For daily minimum temperature, a spatial interpolation scheme accommodating the potential influences of cold air accumulation and the temperature inversion was used. For daily maximum temperature estimation, a spatial interpolation model loaded with the overheating index was used. Daily solar irradiances over sloping surfaces were estimated from nearby synoptic station data weighted by potential relative radiation, which is the hourly sum of relative solar intensity. Precipitation was assumed to increase with the difference between virtual terrain elevation and the DEM multiplied by an observed rate. Validations were carried out by installing an observation network specifically for making comparisons with the spatially estimated temperature pattern. Freezing risk in January was estimated for major fruit tree species based on the DCMs under the recurrence intervals of 10, 30, and 100 years, respectively. Frost risks at bud-burst and blossom of tree flowers were also estimated for the same resolution as the DCMs.

• Journal of Ginseng Research
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• v.44 no.4
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• pp.644-654
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• 2020

Background: Posttraumatic stress disorder (PTSD), a mental disorder induced by traumatic stress and often accompanied by depression and/or anxiety, may involve an imbalance in the neurotransmitters associated with the fear response. Korean Red Ginseng (KRG) has long been used as a traditional medicine and is known to be involved in a variety of pharmacological activities. We used the open field test and forced swimming test to examine the effects of KRG on the depression-like response of rats after exposure to single prolonged stress (SPS), leading to activation of the serotonergic system. Methods: Male rats received KRG (30, 50, and 100 mg/kg, intraperitoneal injection) once daily for 14 days after exposure to SPS. Results: Daily KRG administration significantly improved depression-like behaviors in the forced swimming test, increased the number of lines crossed and time spent in the central zone in the open field test, and decreased freezing behavior in contextual and cued fear conditioning. KRG treatment attenuated SPS-induced decreases in serotonin (5-HT) tissue concentrations in the hippocampus and medial prefrontal cortex. The increased 5-HT concentration during KRG treatment may be partially attributable to the 5-hydroxyindoleacetic acid/5-HT ratio in the hippocampus of rats with PTSD. These effects may be caused by the activation of hippocampal genes encoding tryptophan hydroxylase-1 and 2 mRNA levels. Conclusion: Our findings suggest that KRG has an antidepressant effect in rats subjected to SPS and may represent an effective use of traditional medicine for the treatment of PTSD.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.4
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• pp.235-241
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• 2004

There is a growing concern about the possible increase in inter-annual variation of minimum temperature during the winter season in Korea. This view is strengthened by frequently reported freezing injury to dormant fruit trees, while warmer winters have prevailed recently. The January minimum temperature record at fourteen weather stations was analyzed for 1951-2000. The results showed no evidence of increasing standard deviation at 3 locations between 1951-1980 and 1971-2000, while the remaining 11 stations showed a trend of decreasing standard deviation for the two periods. An empirical model explaining the spatial variation of the standard deviation was derived by regression analysis of 56 stations' data for 1971-2000. Daily minimum temperature and the site elevation may account for 68% of the observed variations. We applied this model to restore the average standard deviation of the January minimum temperature for 1971-2000, and the result was used to produce gridded minimum temperature data for the recurrence interval of 10 and 30 years at 250m resolution. A digital form of the plant hardiness zone map may be developed from this product for site-specific selection of adapted plant species.