• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.2
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• pp.74-87
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• 2016

Potato phenology, growth, and yield are projected to be highly affected by global warming in the future. The objective of this study was to examine the responses of potato growth and yield to environmental elements like temperature, solar radiation, and daylength. Planting date experiments under open field condition were conducted using three cultivars differing in maturity group (Irish Cobbler and Superior as early; Atlantic as mid-late maturing) at eight different planting dates. In addition, elevated temperature experiment was conducted in four plastic houses controlled to target temperatures of ambient temperature (AT), $AT+1.5^{\circ}C$, $AT+3^{\circ}C$, and $AT+5^{\circ}C$ using cv. Superior. Tuber initiation onset was found to be hastened curve-linearly with increasing temperature, showing optimum temperature around $22-24^{\circ}C$, while delayed by longer photoperiod and lower solar radiation in Superior and Atlantic. In the planting date experiments where the average temperature is near optimal and solar radiation, rainfall, pest, and disease are not limiting factor for tuber yield, the most important determinant was growth duration, which is limited by the beginning of rainy season in summer and frost in the late fall. Yield tended to increase along with delayed tuber initiation. Within the optimum temperature range ($17^{\circ}-22^{\circ}C$), larger diurnal range of temperature increased the tuber yield. In an elevated temperature treatment of $AT+5.0^{\circ}C$, plants failed to form tubers as affected by high temperature, low irradiance, and long daylength. Tuber number at early growth stage was reduced by higher temperature, resulting in the decrease of assimilates allocated to tuber and the reduction of average tuber weight. Stem growth was enhanced by elevated temperature at the expense of tuber growth. Consequently, tuber yield decreased with elevated temperature above ambient and drop to almost nil at $AT+5.0^{\circ}C$.

• Korean Journal of Animal Reproduction
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• v.24 no.1
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• pp.97-108
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• 2000

The objectives of this study were performed to increase the efficiency of the culture conditions of embryos produced in vitro, and to assess the developmental potential after transfer of those embryos into recipients. The mean number of folliclular oocytes recovered from an ovary was 10.7. The rates of maturation and fertilization in Grade I oocytes were significantly (P＜0.05) higher than Graden and III. Developmental rate into blastocyst in the culture group of TCM-199 with BOEC were significantly higher (P＜0.05) than the groups of TCM-199 and conditioned medium (24.7% vs. 12.4% and 18.2%). The survivability of post-thawed blastocysts equilibrated for 3 min in EFS solution was significantly (P＜0.05) lower than l0 for 1 and 2 min (32.1% vs. 82.9% and 73.3%). Significantly higher (P＜0.05) survival rate in blastocysts was seen after freezing than in morulae stage embryos. Out of all 105 recipients, 49 (46.7%) were confirmed in pregnant. On pregnancy of cattle, 48 calves were born from 40 recipients. The ratio of twin and single calves was 30.5% (32/40 and 7.6% (8/40), respectively. However, the others composed of abnormal, as judging as 6 (12.2%) for abortion and 3 (6.1%) for stillbirth during the pregnant period.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.2
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• pp.140-148
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• 2018

As the global warming causing desertification increase, there is growing concern about damage of crops. It was to investigate how the treatment with hydrogen peroxide before leaf development affects the growth and yield of sorghum for minimizing a damage of crops to drought. The germination experiment was conducted at alternating temperature of $25^{\circ}C/20^{\circ}C$(12 hr/12 hr) under water stress condition of 0 ~ -0.20 MPa adjusted with PEG solution containing 0 and 10 mM $H_2O_2$. In order to know the effect of foliar application of hydrogen peroxide on the growth of sorghum, 10 mM hydrogen peroxide was treated to leaves at 3-leaf stage of sorghum growing in greenhouse conditions. Seed germination rate was increased by 20% in hydrogen peroxide treatment as compared to the Control. under water stress conditions (-0.15 ~ -0.20 MPa). The length of seedlings was also on the rise by the hydrogen peroxide treatment. In the greenhouse pot experiment, the morphological characteristics (plant height, stem diameter, leaf length, and leaf number) and physiological characteristics (chlorophyll content, chlorophyll fluorescence (Fv/Fm), stomatal conductance) were higher in the plants treated with hydrogen peroxide under the drought stress condition than those of plants of $H_2O$ treatment. Experiment conducted with the soil moisture gradient system showed that the foliar application of hydrogen peroxide increased photosynthetic ability of sorghum plant with respect to SPAD value and stomatal conductance and rooting capacity (root weight and root length) under drought condition. Generally, hydrogen peroxide treatment in sorghum increased the tolerance to drought stress and maintained better growth due to ameliorating oxidative stress.

• Economic and Environmental Geology
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• v.15 no.3
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• pp.123-154
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• 1982

Petrochemical, K-Ar dating, Sand Rb/Sr isotopes, metallogenic zoning, paleomagnetic and geotectonic studies of the Gyongsang basin were carried out to examine applicability of plate tectonics to the post-late Cretaceous igneous activity and metallogeny in the southeastern part of Korean Peninsula. The results obtained are as follows: 1. Bulgugsa granitic rocks range from granite to adamellite, whose Q-Ab-Or triangular diagram indicates that the depth and pressure at which the magma consolidated increase from coast to inland varying from 6 km, 0.5-3.3 kb in the coastal area to 17 km, 0.5-10 kb in the inland area. 2. The volcanic rocks in Gyongsang basin range from andesitic to basaltic rocks, and the basaltic rocks are generally tholeiitic in the coastal area and alkali basalt in the inland area. 3. The volcanic rocks of the area have the initial ratio of Sr^{87}/Sr^{86} varying from 0.706 to 0.707 which suggests a continental origin; the ratio of Rb/Sr changing from 0.079-0.157 in the coastal area to 0.021-0.034 in the inland area suggests that the volcanism is getting younger toward coastal side, which may indicate a retreat in stage of differentiation if they were derived from a same magma. The K_2O/SiO_2 (60%) increases from about 1.0 in the coastal area to about 3.0 in the inland area, which may suggest an increase indepth of the Benioff zone, if existed, toward inland side. 4. The K-Ar ages of volcanic rocks were measured to be 79.4 m.y. near Daegu, and 61.7 m.y. near Busan indicating a southeastward decrease in age. The ages of plutonic rocks also decrease toward the same direction with 73 m.y. near Daegu, and 58 m.y. near Busan, so that the volcanism predated the plutonism by 6 m.y. in the continental interior and 4 m.y. along the coast. Such igneous activities provide a positive evidence for an applicability of plate tectonics to this area. 5. Sulfur isotope analyses of sulfide minerals from 8 mines revealed that these deposits were genetically connected with the spacially associated ingeous rocks showing relatively narrow range of ${\delta}^{34}S$ values (-0.9‰ to +7.5‰ except for +13.3 from Mulgum Mine). A sequence of metallogenic zones from the coast to the inland is delineated to be in the order of Fe-Cu zone, Cu-Pb-Zn zone, and W-Mo zone. A few porphyry type copper deposits are found in the Fe-Cu zone. These two facts enable the sequence to be comparable with that of Andean type in South America. 6. The VGP's of Cretaceous and post Cretaceous rocks from Korea are located near the ones($71^{\circ}N$, $180^{\circ}E$ and $90^{\circ}N$, $110^{\circ}E$) obtained from continents of northern hemisphere. This suggests that the Korean peninsula has been stable tectonically since Cretaceous, belonging to the Eurasian continent. 7. Different polar wandering path between Korean peninsula and Japanese islands delineates that there has been some relative movement between them. 8. The variational feature of declination of NRM toward northwestern inland side from southeastern extremity of Korean peninsula suggests that the age of rocks becomes older toward inland side. 9. The geological structure(mainly faults) and trends of lineaments interpreted from the Landsat imagery reveal that NNE-, NWW- and NEE-trends are predominant in the decreasing order of intensity. 10. The NNE-trending structures were originated by tensional and/or compressional forces, the directions of which were parallel and perpendicular respectively to the subduction boundary of the Kula plate during about 90 m.y. B.P. The NWW-trending structures were originated as shear fractures by the same compressional forces. The NEE-trending structures are considered to be priginated as tension fractures parallel to the subduction boundary of the Kula plate during about 70 m.y. B.P. when Japanese islands had drifted toward southeast leaving the Sea of Japan behind. It was clearly demonstrated by many authors that the drifting of Japanese islands was accompanied with a rotational movement of a clock-wise direction, so that it is inferred that subduction boundary had changed from NNE- to NEE-direction. A number of facts and features mentioned above provide a suite of positive evidences enabling application of plate tectonics to the late Cretaceous-early Tertiary igneous activity and metallogeny in the area. Synthesizing these facts, an arc-trench system of continental margin-type is adopted by reconstructing paleogeographic models for the evolution of Korean peninsula and Japan islands. The models involve an extention mechanism behind the are(proto-Japan), by which proto-Japan as of northeastern continuation of Gyongsang zone has been drifted rotationally toward southeast. The zone of igneous activity has also been migrated from the inland in late-Cretaceous to the peninsula margin and southwestern Japan in Tertiary.

• Horticultural Science & Technology
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• v.32 no.3
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• pp.318-329
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• 2014

In order to gain insight into the physiological responses of plants to high temperature stress, the effects of temperature on Chinese cabbage (Brassica campestris subsp. napus var. pekinensis cv. Detong) were investigated through analyses of photosynthesis and chlorophyll fluorescence under 3 different temperatures in the temperature gradient tunnel. Growth (leaf length and number of leaves) during the rosette stage was greater at ambient $+4^{\circ}C$ and ambient $+7^{\circ}C$ temperatures than at ambient temperature. Photosynthetic $CO_2$ fixation rates of Chinese cabbage grown under the different temperatures did not differ significantly. However, dark respiration rate was significantly higher in the cabbage that developed under ambient temperature relative to elevated temperature. Furthermore, elevated growth temperature increased transpiration rate and stomatal conductance resulting in an overall decrease of water use efficiency. The chlorophyll a fluorescence transient was also considerably affected by high temperature stress; the fluorescence yield $F_J$, $F_I$, and $F_P$ decreased considerably at ambient $+4^{\circ}C$ and ambient $+7^{\circ}C$ temperatures, with induction of $F_K$ and decrease of $F_V/F_O$. The values of RC/CS, ABS/CS, TRo/CS, and ETo/CS decreased considerably, while DIo/CS increased with increased growth temperature. The symptoms of soft-rot disease were observed in the inner part of the cabbage heads after 7, 9, and/or 10 weeks of cultivation at ambient $+4^{\circ}C$ and ambient $+7^{\circ}C$ temperatures, but not in the cabbage heads growing at ambient temperature. These results show that Chinese cabbage could be negatively affected by high temperature under a future climate change scenario. Therefore, to maintain the high productivity and quality of Chinese cabbage, it may be necessary to develop new high temperature tolerant cultivars or to markedly improve cropping systems. In addition, it would be possible to use the non-invasive fluorescence parameters $F_O$, $F_V/F_M$, and $F_V/F_O$, as well as $F_K$, $M_O$, $S_M$, RC/CS, ETo/CS, $PI_{abs}$, and $SFI_{abs}$ (which were selected in this study), to quantitatively determine the physiological status of plants in response to high temperature stresses.

• Journal of Hospice and Palliative Care
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• v.21 no.2
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• pp.51-57
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• 2018

Purpose: End-of-life (EoL) decisions are challenging and multifaceted for patients and physicians. This study was aimed to explore how EoL care is practiced for patients with a do-not-resuscitate (DNR) order. Methods: We retrospectively analyzed medical records of patients who died after agreeing to a DNR order in 2016 at a university hospital. Characteristics including cause of death, intensity of EoL care, and other factors were reviewed and statistically analyzed. Results: Of total 375 patients, 170 patients (45.3%) died with malignancies, and 205 patients (54.6%) with other causes involving the central nervous system (19.2%), pulmonary (14.7%), cardiologic (6.7%) and infectious (6.4%) conditions. Both the cancer and non-cancer patient groups showed a short duration from DNR to death (median 3 days vs 2 days, P=0.629). An intensive care group comprising patients who received one or more intensive treatments such as ventilator (n=205) showed a higher number of non-cancer patients and a shorter duration from DNR to death than a group that withheld treatment before DNR (P<0.05). Conclusion: EoL decisions were made very late by both cancer and non-cancer patients. About half of the patients did not have cancer, and two-thirds of them decided DNR during intensive treatment. To make a good EoL decision, a shared decision making with patients should be done at an earlier stage.

• Journal of Embryo Transfer
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• v.21 no.2
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• pp.147-156
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• 2006

The objective of this study was to supply excellent genetic resources to livestock farms by transferring embryos produced by genetically superior Korean cows (Hanwoo). Eighty Hanwoo donors were superovulated with gonadotropin ($Folltrpin^(R)\;or\;Antorin^(R)$) for 4 days combined with or without progesterone releasing intravaginal device (CIDR) insertion. The collected fresh or frozen-thawed embryos were transferred to 226 farm recipients. In this study, the effect of CIDR insertion in combination with gonadotropin ($Folltrpin^(R)$) treatments initiated at the random stage of estrous cycle on embryo production was evaluated and compared to conventional superovulation protocol. Moreover, the effect of gonadotropin ($Antorin^(R)$) dose in CIDR-treated Hanwoo donors on the embryo yield was determined. In addition, the effects of embryos (fresh vs. frozen-thawed), embryo transfer person, seasons and farms on the pregnancy rate were evaluated. In Hanwoo donors, CIDR insertion in combination with $Folltrpin^(R)$ treatments regardless of estrous detection resulted in increased numbers of total ova (6.5 vs. 5.8) and transferable embryos (3.9 vs. 3.2) compared to the conventional superovulation protocol (p<0.01). In CIDR-treated Hanwoo donors, the higher dose of $Antorin^(R)$ (36 vs. 28 mg) resulted in the increased number of transferable embryos (8.3 vs. 5.4, p<0.05). The embryos (fresh 43.9% vs. frozen-thawed 23.1%) and embryo transfer person (53.9 vs. $0{\sim}16.7%$) significantly affected the pregnancy rate after embryo transfer (p<0.01). These results suggest that CIDR-based superovulation protocol may be effectively used for production of superior Hanwoo embryos and, multiple ovulation and embryo transfer in Hanwoo might be effectively applied for livestock improvement if pregmancy rate with frozen-thawed embryos and embryo transfer skill would be improved.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.3
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• pp.254-260
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• 2015

Changes of the growth, quality and physiological response of Chinese cabbage cv 'Chunkwang' in response to five different temperature treatments based on climate change scenario were investigated during the growing season. The treatments consisted of normal year temperature $-2.0^{\circ}C$ (I), normal year temperature (II; Control group), normal year temperature $+2.0^{\circ}C$ (III), normal year temperature $+4.0^{\circ}C$ (IV), and normal year temperature $+6.0^{\circ}C$ (V). Regarding fresh weight, number of leaves, and leaf area were high in group IV, and V before the head formation stage, but it has decreased during the later growth period. Rate of frangibleness sympton was the highest in group V as 85.7%, and it was decreased in group IV (64.3%), group III (28.6%), group II (14.3%), and group I (7.1%). Regarding photosynthetic rate, group III, IV, and V showed relatively high photosynthetic rate at 20 DAP but it was reduced dramatically during the later growth period. Transpiration and stomatal conductance showed the similar trend with the photosynthetic rate. When comparing the chlorophyll fluorescence reaction of each treatment group at 50 DAP, Fv/Fm in group I was highest as 8.04 among all treatment groups and the lowest in group IV as 7.15.

• The Journal of the Korea Contents Association
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• v.11 no.5
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• pp.242-251
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• 2011

A curriculum of study demands a change as period of time and society evolve. Therefore, at this point where changes are required, this study is to analyze and evaluate the curriculums which will enhance and improve current studies as a preceding stage. The research was based on the survey by groups of education experts and 19 universities with current curriculum of study in radiologic science, and their references. The study was focused on the scope of work by radiologic technologist, change of college systems, academic research about radiologic science, and the improvement and the future of radiologic science field in perspective to globalization and the digital era. In terms of work scope, angiography and interventional radiology at 6 to 8 schools, fluoroscopy at 4 schools, ultrasound and practices at 6 schools, magnetic resonance image at 2 schools were found to be unestablished. The basic medical subjects, humuan physiology, human anatomy and practices, medical terminology courses were set up at most schools; however, pathology at 5 schools, image anatomy at 6 schools, clinical medicine at 11 schools were yet opened. Among the basic science and engineering subjects, general biology and its practices at 11 schools, general physics and its practices at 14 schools, and general chemistry and its practices at 8 schools were established which is about a half from a total number of schools. Only 4-5 schools established digital subjects such as, health computer, computer programming, PACS which are the basic major subjects. In order to provide academic improvement in radiologic science, digitalized education and globalization, and basis for future-oriented education for the field of radiologic science, including expanded scope of work, it is acknowledged that curriculums that are opened and run at each school need to be standardized. Therefore, the need for introduction of certificate for the radiologic science education courses are suggested.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.4
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• pp.652-663
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• 1999

Craniosynostosis, the premature fusion of cranial sutures, presumably involves disturbance of the interactions between different tissues within the cranial sutures. Interestingly, point mutaions in the genes encoding for the fibroblast growth factor receptors(FGFRs), especially FGFR2, cause various types of human craniosynostosis syndromes. To elucidate the function of these genes in the early morphogenesis of mouse cranial sutures, we first analyzed by in situ hybridization the expression of FGFR2(BEK) and osteopontin, an early marker of osteogenic differentiation, in the sagittal suture of calvaria during embryonic(E15-E18) and postnatal stage(P1-P3). FGFR2(BEK) was intensely expressed in the osteogenic fronts, whose cells undergo differentiation into osteoprogenitor cells that ultimately lay down the bone matrix. Osteopontin was expressed throughout the parietal bones excluding the osteogenic fronts, the periphery of the parietal bones. To further examine the role of FGF-mediated FGFR signaling in cranial suture, we did in vitro experiments in E15.5 mouse calvarial explants. Interestingly, implantation of FGF2 soaked beads onto both the osteogenic fronts and mid-mesenchyme of sagittal suture after 36 hours organ culture resulted in the increase of the tissue thickness and cell number around FGF2 beads, moreover FGF4-soaked beads implanted onto the osteogenic fronts stimulated suture closure due to an accelerated bone growth, compared to FGF4 beads placed onto mid-mesenchyme of sagittal suture and BSA control beads. In addition FGF2 induced the ectopic expression of osteopontin and Msx1 genes. Taken together, these data indicate that FGF-mediated FGFR signaling has a important role in regulating the cranial bone growth and maintenance of cranial suture, and suggest that FGF-mediated FGFR signaling is involved in regulating the balance between the cell proliferation and differentiation through inducing the expression of osteopontin and Msx1 genes.