• Korean Journal of Soil Science and Fertilizer
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• v.30 no.1
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• pp.3-15
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• 1997

Iron oxide compounds in 8 selected Cheju Island soil samples have been analized by X-ray fluorescence spectrometer(XRF), X-ray diffractometry(XRD), selected chemical techniques, and $M{\ddot{o}}ssbauer$ spectroscopy. The result of this analysis by XRF shows that the rate of quantity of $Fe_2O_3$ in 8 soil samples was from 8.03wt.%(Daejeong paddy soil) to 18.21wt.%(Songag soils). Songag, Heugag and Gueom soils were detected to have lower peaks of intensity of hematite by XRD. In addition, these soils were not detected to have hematite and goethite peaks. Ferrihydrite, which is a short-range-order mineral commonly present in volcanic ash soil, was not detected by XRD due to low concentration and/or poor cristallinity. Ferrihydrite contents estimated from Feo values were 8.8~35.2g/kg for volcanic ash soils and 0.85g/kg for the Daejeong soil. Most of the soil samples represented by the paramagnetic $Fe^{3+}$ doublet obtained from $M{\ddot{o}}ssbauer$ spectra at room temperature and 18K were considered to arise from the presence of ferrihydrite, superparamagnetic goethite, and silicate minerals. Also the paramagnetic $Fe^{2+}$ doublets are attributable to primary minerals such as olivine, illite, chlorite, augite, biotite, and hornblende. Goethite and hematite were identified as the dominant crystalline iron oxides in these soils from $M{\ddot{o}}ssbauer$ spectra obtained at room temperature and 18K. All the soil samples exhibited strong superparamagnetic relaxation. Collapse of the $M{\ddot{o}}ssbauer$ magnetic hyperfine splitting at room temperature was due to the small size(${\sim}180{\AA}$) of the oxide particles and/or Al-subsituted goethite.

• Journal of Sericultural and Entomological Science
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• v.24 no.2
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• pp.55-72
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• 1983

These studies were done to find out any difference, ultrastructural, physical or chemical, between the shells of diapausing and non-diapausing eggs of the silkworm, Bombyx mori L. 1. From the electron-microscopic observation, the egg shells have four distinctive layers. In addition to the four layers, the shells in the diapausing eggs has another layer with low electron density on its surface. 2. The permeability of the egg shell to hydrochloride was much lower in diapausing egg than in non-diapausing egg. Also the permeability changed in the opposite directions with the egg age: the diapausing eggs decreased while non-diapausing ones increased. 3. The permeability increased when the diapausing egg shell was treated with HCl. When they were treated with ether, however, the increase in permeability was much smaller. It seems there was an ether soluble material involved in the content of the egg shell. 4. The diapausing eggs were also much more resistant to desiccation than the non-diapausing ones. The former, when treated with HCl or chilling, became less resistant to desiccation. 5. The positive histochemical response of the egg shell to PAS-Alcian blue and protein stainings suggests presence of abundant proteins and carbohydrates in the egg shell. On the other hand, the staining response to lipid was more positive in the inner layers than in the outer layer of the shell. 6. The egg shell adhesives seems to be mucopolysaccharides produced by colleterial glands, since the oviposited eggs showed a positive responses to carbohydrate and negative to lipid-staining chemicals, but not the mature oocytes in the ovarioles. 7. There were two bands on the electrophoretic pattern of the SH proteins extracted from the egg shells both in the diapausing egg and non-diapausing one: a slow moving major component and a fast moving minor one. However, the electrophoretic mobility showed a difference in the minor components between them. It is evident that the fast moving minor one of non-diapausing egg ran a little further than that of diapausing egg. 8. In amino acids analysis, no significant differences were found in their composition between diapausing and non-diapausing egg and SH proteins contain relatively more glycine and less cystine.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.2
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• pp.126-136
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• 2008

Tobacco plants grown in pots by sand culture for 70 days after transplanting were used to evaluate the sensing distance and measurement efficiency of ground-based remote sensors. The leaf distribution of tobacco plant and sensing distance from the sensors to the target leaves were controlled by two removal methods of leaves, top-down and bottom-up removal. In the case of top-down removal, the canopy reflectance was measured by the sensor located at a fixed position having an optimum distance from the detector to the uppermost leaf of tobacco every time that the higher leaves were one at a time. The measurement of bottom-up removal, a the other hand, was conducted in the same manner as that of the top-down removal except that the lower leaves were removed one by one. Canopy reflectance measurements were made with hand held spectral sensors including the active sensors such as $GreenSeeker^{TM}$ red and green, $Crop\;Circle\;ACS-210^{TM}$ red and amber, the passive sensors of $Crop\:Circle^{TM}$, and spectroradiometer $SD2000^{TM}$. The reflectance indices by all sensors were generally affected by the upper canopy condition rather than lower canopy condition of tobacco regardless of sensor type, passive or active. The reflectance measurement by $GreenSeeker^{TM}$ was affected sensitively at measurement distance longer than 120 cm, the upper limit of effective sensing distance, beyond which measurement errors are appreciable. In case of the passive sensors that has no upper limit of effective distance and $Crop\;Circle^{TM}(ACS210)$ that has the upper limit of effective sensing distance specified with 213 cm, longer than that of estimated distance, the measurement efficiency affected by the sensing distance showed no difference. This result suggests that it is necessary to use the sensor specified optimum distance. The result revealed that active sensors are more superior than their passive counterparts in establishing between the relative ratio of reflectance index and the dry weight of tobacco treated by top-down removal, and in the evaluation of biomass. $The\;Crop\;Circle\;ACS-210^{TM}$ red was proved to have the highest efficiency of measurement, followed by $Crop\;Circle^{TM}(ACS210)$ amber and $GreenSeeker^{TM}$ red, $Crop\;Circle^{TM}$ passive, $GreenSeeker^{TM}$ green, and spectroradiometer, in descending order.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.2
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• pp.75-82
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• 2008

In order to establish environmentally friendly phosphorus(P) and potassium(K) fertilizer application rates for rice cultivation in Korea, a field experiment was conducted in two different characterized paddy soils, higher and lower P and K content in soil from 2005 to 2006 in Suwon, Korea. Chuchong which is typical rice variety in Korea, was selected for experiment. Rice yields in base P-K fertilizer level ($30-30kg\;ha^{-1}$) and no P-K fertilizer level were 97~98% and 93~97% of standard P-K fertilizer level ($45-57kg\;ha^{-1}$), respectively. At the lower content of P and K in immatured paddy soil, the yield of no P plot was decreased by 7% compared to that of standard P-K plot. Significant difference in rice yield and yield characteristics was found neither in standard P-K fertilization plot nor in base P-K fertilization plot. There was no significant difference in P and K uptake at the harvest stage between standard P-K fertilizer plot and base P-K fertilizer plot. Phosphorus and K uptake was slightly decreased in no fertilizer plots compared to standard fertilizer plot. Phosphorus and K use efficiency of rice plant in base fertilizer plot was higher than that in standard fertilizer plot. Available phosphorus and exchangeable potassium content in soil at the harvest stage were increased in both standard and base fertilizer plot. But no significant difference of P and K content in ? was found between standard fertilizer plot and base fertilizer plot. Rice quality characteristics such as proportion of brewers rice, damaged kernel, broken rice, and content of amylose and protein were lowered in the base fertilizer plot than the standard fertilized plot, while the proportion of perfect kernel increased in the base fertilizer plot From the results, we generally recommend the base P-K fertilization ($30-30kg\;ha^{-1}$) instead of standard P-K fertilization ($45-57kg\;ha^{-1}$) for rice cultivation in Korea.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.2
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• pp.136-141
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• 2013

Lowering tree height has been a key practice for efficient management of persimmon orchards. This experiment was conducted to assess whether fertilization rates could be reduced after lowering the tree height by heavy pruning. Twelve-year-old 'Uenishiwase' persimmon trees were lowered to 2 m from over 3 m by severe dormant pruning, and then conventional fertilization rate was applied to some trees in April (N 224 g, $P_2O_5$ 172 g, and $K_2O$ 172 g per tree), June (N 112 g and $K_2O$ 99 g per tree), and October (N 112 g and $K_2O$ 99 g per tree). At the same time, 1/3 or 2/3 of the conventional rate and none were applied to other trees, respectively. Non-application decreased shoot length and reduced number of unnecessary secondary shoots by 39% compared with the conventional rate, not affecting yield and weight, color, firmness, and soluble solids of fruits. No significant difference was also found in the yield and the fruit characteristics among the trees fertilized with different rates. Concentrations of soluble sugars, starch, N, and K of dormant shoots in March of the following year were not significantly changed by the different treatments of the previous year. There was no significant difference of shoot growth and yield among the treatments the following year when the same fertilization rate was supplied to all the trees. Results indicated that fertilization rate could be reduced to less than 1/3 of conventional rate to save the cost and stabilize shoot vigor when tree height is lowered by severe pruning.

• Journal of Sericultural and Entomological Science
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• v.49 no.1
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• pp.14-17
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• 2007

A new silkworm variety Golden silk for spring rearing season is $F_1$ hybrid between Jam311, a Japanese race bred from introduction breeding and Jam312, a Chinese race from introduction breeding. In the local adaptability test performed at 8 local areas in spring of 2006, "Golden silk" was showed 7 percent higher in hatchability than authorized silk-worm races laval. "Golden silk" was receded higher 1.7 percent, 2.2 percent in pupation rate, best cocoon rate respectively than Chunsujam. The larval period shortened for 1.12 day even though low record to the several items including productivity than Chunsujam. "Golden silk" was showed 1,031 m, 2.97 denier in length of cocoon filament, weight of cocoon filament respectively. The concentration of Deoxynojirimycin(DNJ) was measured 4.34 mg in "Golden silk", high then to "Chunsujam"(3.81 mg). In the Paecilomyces tenuipes production ability test, the pupal weight of "Golden silk" was 1.20g.

• Journal of Trauma and Injury
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• v.21 no.1
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• pp.28-35
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• 2008

Purpose: This study was conducted to examine the clinical significance IV-contrasted helical abdomen computed tomography (CT) as a diagnostic screening tool to evaluate hollow viscus injury in blunt abdominal trauma patients. Methods: This is a retrospective study encompassing 108 patients, presenting to Korea University Medical Center (KUMC) Emergency Department (ED) from January 2007 to December 2007, with an initial CT finding suggestive of intra-abdominal injury. An initial non-enhanced abdomen CT was taken, followed by an enhanced CT with intravenous contrast. Patients' demographic data, as well as the mechanisms of injury, were inquired upon and obtained, initial diagnosis, as dictated by specialized radiologists, were added to post-operational (post-OP) findings and to additional CT findings acquired during their hospital stays, and all were combined to arrive at final diagnosis. Initial CT findings were further compared with the final diagnosis, yielding values for sensitivity, specificity, and accuracy, as well as positive and negative predictive values. Patients were further divided into two groups, namely, those that underwent operational intervention and those that did not. The initial CT findings of each group were subsequently compared and analyzed. Results: Initial CT scans revealed abnormal findings in a total of 212 cases - solid organ injuries being the most common finding, as was observed in 97 cases. Free fluid accumulation was evident in another 69 cases. Based on the CT findings, 77 cases (71.3%) were initially diagnosed as having a solid organ injury, 20 cases (18.5%) as having a combined (solid organ + hollow viscus) injury, and 11 cases (10.2%), as having an isolated hollow viscus injury. The final diagnosis however, were somewhat different, with only 67 cases (62.0%) attributed to solid organ injury, 31 cases (28.7%) to combined injury (solid + hollow), and 10 cases (9.3%) to hollow viscus injury. The sensitivity (CI 95%) of the initial helical CT in diagnosing hollow viscus injury was 75.6%, and its specificity was 100%. The accuracy in diagnosing hollow viscus injury was also meaningfully lower compared to that in diagnosis of solid organ injury. Among patients initially diagnosed with solid organ injuries, 10 patients (2 from follow-up CT and 8 from post-OP finding) turned out to have combined injuries. A total of 38 patients underwent an operation, and the proportion of initial CT findings suggesting free air, mesenteric hematoma or bowel wall thickening turned out to be significantly higher in the operation group. Conclusion: Abdominal CT was a meaningful screening test for hollow viscus injury, but the sensitivity of abdominal CT was significantly lower in detecting hollow viscus injury as compared to solid organ injury. This calls for special consideration and careful observation by the ED physicians when dealing with cases of blunt abdominal trauma.

• Radiation Oncology Journal
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• v.9 no.2
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• pp.253-263
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• 1991

Twenty-seven patients with unresectable extrahepatic bile duct carcinoma (n=21) or with microscopic evidence of tumor rest after aggressive surgery for extrahepatic bile duct carcinoma (n=6) between 1985 and 1990 were given radiotherapy consisting intentionally external radiotherapy and/or intraluminal therapy using Gamma-Med 12i (192-Ir) high dose rate (HDR) remote control afterloading system following bile drainage procedures and Gianturco stent insertion. The objectives of this study has been to assess the feasibility and effects on survival of a combination of external radiotherapy and brachytherapy with which we hope to achieve optimal loco-regional control for patients with unresectable extrahepatic bile duct tumors. Sixteen patients were men and eleven were women, and the mean age was 58 years (34-70). 10MV X-ray was used for radiation therapy, with the total dose ranging from 45 Gy to 55 Gy, and intraluminal brachytherapy performed after external radiotherapy, with the dose of total 15 Gy. The minimum follow up was 12 months. Failure were predominantly local-regional, without distant failure. Median survival was 10 months; 2-year actuarial survival rates was $21\%$. Median survival for common hepatic duct (CHD) cancer was 9 months; for common bile duct (CBD) cancer, was 16 months. And median survival for incomplete surgery/external radiotherapy group and external/intraluminal radiotherapy group was 10 months; for external radiotherapy alone group, was 6 months. Use of chemotherapy and/or hyperthermia were not affected in survival. Therefore, our result is that the survival rates in the group of external/intraluminal radiotherapy were comparable with ones in the group of incomplete resection/external radiotherapy, and so we believe that the aggressive local and regional radiotherapy can improve the quality of life and the survival length.

• Radiation Oncology Journal
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• v.24 no.1
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• pp.58-66
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• 2006

Purpose: Renal irradiation can lead to the development of radiation nephropathy, and this is characterized by the accumulation of extracellular matrix and final fibrosis. To determine the possible role of the glomerular epithelial cell, the radiation-induced changes in the expression of its genes associated with the extracellular matrix were analyzed. Materials and Methods: Rat glomerular epithelial cells (GEpC) were irradiated with a single dose of 0, 2, 5, 10 and 20 Gy with using 6 MV LINAC (Siemens, USA), and the samples were collected 6, 24, 48 and 72 hours post-irradiation, respectively. Northern blotting, western blotting and zymography were used to measure the expression level of fibronectin (Fn), plasminogen activator inhibitor-1 (Pai-1), matrix metalloproteinases-2, 9 (MMP-2, 9), tissue inhibitor of metalloproteinase-2 (TIMP-2), tissue-type plasminogen activator (t-PA) and urokinase-type plasminogen activator (u-PA). Results: Irradiation with a single dose of 10 Gy resulted in a significant increase in Fn mRNA since 24 hours post-irradiation, and a single dose of 5 and 10 Gy significantly increased the Fn immunoreactive protein measured 48 hours post-irradiation. An increase in Pai-1 mRNA and protein was also observed and especially, a single dose of 10 Gy significantly increased the mRNA measured 24 and 48 hours post-irradiation. The active MMP-2 measured 24 hours post-irradiation slightly increased in a dose dependent manner, but this increase did not reach statistical significance. The levels of MMP-9, TIMP-2, t-PA and u-PA appeared unaltered after irradiation. Conclusion: Irradiation of the glomerular epithelial cells altered the expression of genes associated with the extracellular matrix, implying that the glomerular epithelial cell may be involved in the development of radiation nephropathy.

• Radiation Oncology Journal
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• v.24 no.1
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• pp.37-43
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• 2006

Purpose: We wanted to determine the clinical characteristics and prognosis according to the VEGF expression in stage II cervical carcinoma patients treated with definitive radiotherapy. Materials and Methods: We enrolled 31 patients who were diagnosed with cervical cancer from 1995 to 2003 at Samsung Medical Center and their paraffin block tissue samples were available for study. The median age of the patients was 65 years. The mean tumor size was 4.1 cm $(range:\;1.2{\sim}8.2cm)$. Seven patients (22.6%) were suspected of having pelvic lymph node metastasis. An external beam irradiation dose of 45-56.4 Gy was administered to the whole pelvis with a 15 MV linear accelerator, and an additional 24 Gy was given to point A by HDR intracavitary brachytherapy. VEGF staining was defined as positive when more than 10% of the tumor cells were stained. The median follow-up duration was 58 months. Results: A positive VEGF expression was observed in 21 patients (67.7%), There was no significant correlation between the VEGF expression and pelvic lymph node metastasis, tumor size and the response of radiotherapy. During follow-up, 7 patients had recurrence. The complete response rate was not significant between the VEGF(-) and VEGF(+) tumors. However, the VEGF(+) tumors showed a significantly higher recurrence rate in comparison with the VEGF(-) tumors (p=0.040), The three year disease-free survival rates were 100% and 66.7%, respectively, for patients with VEGF(-) or VEGF(+) tumor (p=0.047), Conclusion: The VEGF expression was a significant factor for recurrence and disease-free survival. However, the significance of the VEGF expression is still controversial because of the various definitions of VEGF expression and the mismatches of the clinical data in the previous studies.