• Journal of radiological science and technology
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• v.39 no.4
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• pp.509-516
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• 2016

A dental panoramic radiography which usually uses low level X-rays is subject to the Nuclear Safety Act when it is installed for the purpose of education. This paper measures radiation dose and spatial dose rate by usage and thereby aims to verify the effectiveness of radiation safety equipment and provide basic information for radiation safety of radiation workers and students. After glass dosimeter (GD-352M) is attached to direct exposure area, the teeth, and indirect exposure area, the eye lens and the thyroid, on the dental radiography head phantom, these exposure areas are measured. Then, after dividing the horizontal into a $45^{\circ}$, it is separated into seven directions which all includes 30, 60, 90, 120 cm distance. The paper shows that the spatial dose rate is the highest at 30 cm and declines as the distance increases. At 30 cm, the spatial dose rate around the starting area of rotation is $3,840{\mu}Sv/h$, which is four times higher than the lowest level $778{\mu}Sv/h$. Furthermore, the spatial dose rate was $408{\mu}Sv/h$ on average at the distance of 60 cm where radiation workers can be located. From a conservative point of view, It is possible to avoid needless exposure to radiation for the purpose of education. However, in case that an unintended exposure to radiation happens within a radiation controlled area, it is still necessary to educate radiation safety. But according to the current Medical Service Act, in medical institutions, even if they are not installed, the equipment such as interlock are obliged by the Nuclear Safety Law, considering that the spatial dose rate of the educational dental panoramic radiography room is low. It seems to be excessive regulation.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.2
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• pp.88-100
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• 1998

Since fractures may serve as major conduits of groundwater flow in crystalline rocks, characterization of conductive fractures is especially important for interpretation of flow system. In this study, characterization of fractures to investigate hydraulically conductive fractures in gneisses at an abandoned mine area was performed. The orientation, width, length, movement sense, infilling materials, spacing, aperture, roughness of both joints and faults and intersection and connectivity to other joints were measured on outcrops. In addition, characteristics of subsurface fractures were examined by core logging in five boreholes, of which the orientations were acquired by acoustic televiewer logging from three boreholes. The dominant fracture sets were grouped from outcrops; GSet 1: N50-82$^{\circ}$E/55-90$^{\circ}$SE, GSet 2: N2-8$^{\circ}$E/56-86$^{\circ}$SE, GSet 3: N46-72$^{\circ}$W/60-85$^{\circ}$NE, GSet 4:Nl2-38$^{\circ}$W/15-40$^{\circ}$SW and from subsurface; HSet 1: N50-90$^{\circ}$E/55-90$^{\circ}$SE, HSet 2: N10-30$^{\circ}$E/50-70$^{\circ}$SE, HSet 3: N20-60$^{\circ}$W/50-80$^{\circ}$NE, HSet 4: N10-50$^{\circ}$E/$\leq$40$^{\circ}$NW. Among them, GSet 1, GSet 3 and HSet 1, HSet 3 are the most intensely developed fracture sets in the study area. The mean fracture spacings of HSet 1 are 30-47cm and code 1 fractures, such as faults and open fractures, comprise 21.0-42.9 percent of the whole fractures in each borehole. HSet 3 shows the mean fracture spacings of 55-57cm and the ratio of code 1 fractures is 15.4-26.9 percent. In spite of the mean fracture spacing of 239cm, code 1 fractures of HSet 4 have the highest ratio of 54.5 percent. From the fact that faults or open fractures have high hydraulic conductivity, it can be inferred that the three fracture sets of N55-85$^{\circ}$E/50-80$^{\circ}$SE, N20-60$^{\circ}$W/50-75$^{\circ}$NE and N10-30$^{\circ}$E/$\leq$30$^{\circ}$NW from a fracture system of relatively high conductivity. It is indirectly verified with geophysical loggings and constant injection tests performed in the boreholes.

• Radiation Oncology Journal
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• v.17 no.2
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• pp.141-145
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• 1999

Purpose : Granisetron is a potent, the most selective 5-HT3 receptor antagonist and is reported to b effective in treatment of radiation-induced emesis. The antiemetic efficacy and safety of oral granisteron was evaluated in patients with receiving highly emetogenic treatment by conventional fractionated irradiation. Materials and Methods : Patients with various cancers who were being treated with irradiation were accrued into the present study. The intensity of nausea was evaluated on first 24 hours and on day-7 by patients according to the degree of interference with normal daily life as followings; a) none; b) present but no interference with normal daily life (mild): c) interference with normal daily life (moderate): and d) bedridden because of nausea (severe). Non or mild state was considered to indicate successful treatment. The efficacy of antiemetic treatment was graded as follows; a) complete response; no vomiting, no worse than mild nausea and receive no rescue antiemetic therapy over the 24h period, b) major response; either one episode of vomiting or moderate/severe nausea or had received rescue medication over 24h period, or any combination of these, c) minor response; two to four episodes of vomiting over the 24h period, regardless of nausea and rescue medication, d) failure; more than four medication. The score of the most symptom was recorded and the total score over 24 hours was summarized. The complete or major response was considered to indicate successful treatment. Results : A total of 10 patients were enrolled into this study, and all were assessable for efficacy analysis. Total nausea control was achieved in 90$\%$ (9/10:none=60$\%$ plus mild=30$\%$) of total patients after 7 days. The control of vomiting by granisteron was noted in seven patients (70$\%$) of complete response and three (30$\%$) of major response with a hundred-percent successful treatment over 7 days. The minor response or treatment failure were not observed. No significant adverse events or toxicities from granisetron were recorded in patient receiving granisetron. Conclusion : We concluded that granisetron is a highly effective antiemetic agent in controlling radiotherapy-induced nausea or vomiting with a minimal toxicity profile.

• Journal of Preventive Medicine and Public Health
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• v.30 no.4 s.59
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• pp.764-778
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• 1997

To find the medical insurance utilization of workers when suffering from low back pain, an analysis was made toward the data of medical insurance benefits matched with the general characteristics of 10,183 workers, who were registered continuously from 1993 to 1995 at a medical insurance cooperation for industrial workers. The results were as follows; 1. The period prevalence of the medical insurance utilization for low back pain for 3 years from 1993 to 1995 was calculated as 17.1% for male workers and 19.4% for female workers. Most common cause of utilization was other dorsopathies including the herniation of lumbar discs. 2. The utilization rate increased significantly as the present age and the age joining the company got older(p<0.001). As the duration of employment got longer, the utilization rate of the male showed the tendency to increase and that of the female increased significantly(p<0.05). Among male workers employed at cement and concrete manufacturing companies showed higher utilization rate and among female laborers showed significantly higher utilization rate than clerical workers(p<0.01). 3. Annual utilization rate for low back pain didn't show any difference, but the portion of other dorsopathies among cause of utilization showed the tendency to increase from 1993 to 1995. 4. The mean number of claims for outpatient medical care for low back pain differed significantly by age, working duration, type of industries, income level(p<0.05), and the mean of total visiting days for care of low back pain differed significantly by working duration. In conclusion, considering the fact that the medical insurance utilization for low back pain increased annually and other dorsopathies including the herniation of dorsopathies were increasing, an effective preventive or management program for low back pain toward worker employed at industries were required.

• Journal of radiological science and technology
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• v.28 no.4
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• pp.279-286
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• 2005

Purpose : There are two modalities, those are small bowel series(SBS) and abdominal pelvic computed tomography(CT), for diagnosis of small bowel disease. The aim of this study is to lend radiological technologists who are doing the two modalities assistance in the understanding characteristic of disease by comparing the two results. Meterials and method : 284 patients were examined the two SBS and abdominal pelvic CT together from 1999 to 2003. 250 ml $BaSO_4$ suspension 40 w/v% and 600ml carboxy methyl cellulose 0.5 w/v% were used for SBS. Abdominal Pelvic CT was examined in one hour before taking 450 ml $BaSO_4$ suspension 1.5 w/v%. The CT scan was done in 72 sec after 150 ml contrast media injection. the used protocol was helical mode 5:5 mm pitch 1.375:1, speed 27.50, exposure 120 kv, 240 mA, tube rotation time 0.5 sec. the statistic analysis was conducted with statistical program SPSS 10 version with frequency and crossing analysis. P-value less than 0.05 were considered significant. Results : In the results of SBS, normal findings were 131 patients(46.1%), inflammatory bowel disease(IBD) 64(22.9%), ischemia+ileocolitis+vasculitis 22(7.7%), Obstruction+stricture 21(7.7%) and Others 45(15.9%). In the results of abdominal pelvic CT, normal findings were 103 patients(36.3%), inflammatory bowel disease 65(22.9%), wall thickening+lymphadenopathy 42(14.8%), Fluid collection 17(6%), and Others 57case(20%). The same results of the two were 130patients(45.8%). 30patients(10.6%) of normal finding in SBS were diagnosed as wall thickening+lymphadenopathy and IBD in CT, and 15patients(5.3%) of normal finding in CT were diagnosed as ischemia+ileocolitis+vasculitis, mass and IBD in SBS(p<0.05). Transit time delay was diagnosed in 10patients(3.5%) on only SBS, wall thickening+lymphadenopathy was diagnosed in 20patients(7%) in only CT(p<0.05). Conclusion : We think that proper examination method will be selected in the small bowel disease, if we understand the characteristics of the disease and method.

• Research in Plant Disease
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• v.17 no.1
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• pp.66-74
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• 2011

In 2005, a survey was conducted to identify virus diseases on victory onion, Allium victorialis var. platyphyllum grown in Ulleung island located in the East Sea. A total of 61 samples were collected from victory onion in the neighborhood of Seonginbong. The identification of viruses from the samples were carried out by electron microscopy and RT-PCR using primers species specific to GCLV, LYSV, SLV, OYDV and genus specific to Allexivirus, respectively. From sixty-one samples, filamentous rod particles (600-900 nm) were detected from four victory onion samples in EM, three samples containing SLV and one sample containing both SLV and Allexivirus in RT-PCR analysis, respectively. Victory onions naturally infected by the viruses were asymptomatic apparently. The viruses detected by RT-PCR were further characterized by the nucleotide sequence analysis of the coat protein region. Three isolates of SLV showed approximately 99% identities in the nucleotide and amino acid sequences, suggesting that they were likely to be the same strain. On the other hand, they showed approximately 75.7~83.7% identities in the nucleotide and 89.2~97.0% in amino acid sequences compared with the previously reported SLV isolates in Allium. The CP gene of the Allexivirus showed approximately 99.2% nucleotide identities and 98.8% amino acid identities with Garlic virus A. However, there was relatively low homology ranging from 60.6% to 81.5% compared with other Allexiviruses (GarV-C, GarV-E, GarV-X, GMbMV, and Shal-X). These data suggested that two viruses, SLV and GarV-A identified from victory onion, are named SLV-Ulleungdo and GarV-A-Ulleungdo, respectively. This is the first report of viruses infecting victory onion.

• Journal of Chest Surgery
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• v.30 no.4
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• pp.363-372
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• 1997

One hundred forty-four patients underwent operation for coarctation of the aorta at Seoul National University Children's Hospital between June 1986 and Decembsr 1995. Age ranged 0.1 to 191 months. Of these 78.5%(113) were infants. We classified the patients in terms of the anatomic location of coarctatiln and the associatCd anomalies(I[401= primary coarctation, 11(741=isthmic hypoplasia, lIIf30)=tubular hypoplasia involving transverse arch, Ar63 =with ventricular septal defect, B(28)=with other major cardiac defects). Subcalvian flap coarctoplasty(60), resection & anastomosis(44), extended aortoplasty(26), and onlay patch(14) were used as surgical methods. Overall operative mortality was 16.0(23/144)%. The hospital mortality was signific'antly higher in patheints with type 111, subtype B, younger age(under 3 months), extended aortoplasty(p(0.01). However, one-stage total repair in patients with subtype A or B were not found to be a predictor of hospital death. Restenosis had occured in 18 patients among 121 survivals(14. 9%). The mean follow-up period was 29.1 $\pm$28.8(0~129.2) months. Preoperative, immediate postoperative(within 3 months after operation) and postoperative(later than 6 months after operation) echocardiographic data on the dimensions of ascending aorta(AA), transverse arch(TA), an4 aortic isthmus(Al) were available in 77 patients(I=20, ll=42, 111= 15). Preoperative and postoperative aortic isthmus(All) and tra sverse arch indices(TAI), defined as TAIAA & AIIAA respectively, were compared. Immediate postoperative All in type 1, II and TAI in type 111 were significantly smaller in stenotic than non-stenotic group suggesting incomplete relieves of stenotic segment Younger age, subclavian coarctoplasty in patient under 3 months of age were round to be the risk factors for restenosis in this series. In conclusion, We found that aortic arch index and transverse arch index can be a useful tool to figure out the anatomic and clinical characteristics of the patients with aortic coarctation, and that anatomy, associated anomalies, age, and surgical methods may influence the surgical outcome of the coarctation repair.

• Korean Journal of Weed Science
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• v.31 no.3
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• pp.221-228
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• 2011

Weed control is of fundamental importance when planting horticultural crops, particularly during the establishment phase. Weeds compete for nutrients, water and light, and can severely threaten the survival and early growth of newly planted crops. Failure to control weeds represents one of the single most important factors leading to crop loss. Knowledge on the existence of the diversity of weed species in greenhouses is of our main concern in this study in order to develop a most efficient and effective weed control strategies. Sixty-two greenhouses were surveyed in 3 cities and counties of Gyeongnam area in March to October 2009 to investigate the feature of weed occurrence in polyvinyl chloride (PVC) after harvesting of the main crops. Forty-one weed species were identified and classified to 18 families which were composed of 14 annual weeds, 18 summer annual weeds and 9 perennial weeds. On the other hand, broadleaf, grasses and sedges recorded with 30, 7 and 4 weed species, respectively. Asteraceae was the most dominant weed species (9 species) noted followed by Poaceae (7 species), Cyperaceae (4 species), Caryophyllaceae and Brassicaceae (3 species respectively) and other families have 1~2 species. The dominant weed species occurred in the greenhouse based on the summed dominance ratio. These weeds were Digitaria sanguinalis, Cyperus iria, Portulaca oleracea, Rorippa islandica, Mazus japonicas, Cardamine flexousa, and Eclipta prostrata and others. Weed occurrence in the greenhouse after horticultural crops consisted of summer annuals (4 species), winter annuals (3 species), and perennial annuals (1 specie). The dominant species occurred in tilled soil based on summed dominance ratio of weeds were Cardamine flexousa (88.1%), Eclipta prostrate (57.4%) and Portulaca oleracea (55.2%). Comparison of weed occurrence was thoroughly surveyed also in which field without PVC, weed species were Portulaca oleracea (55.2), Eclipta prostrata (57.9%) and Trigonotis peduncularis (25.1%) and field with PVC, the identified weeds were Portulaca oleracea (98.75), Trigonotis peduncularis (49.1%), and Eclipta prostrata (36.8%).

• Journal of Life Science
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• v.18 no.12
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• pp.1625-1630
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• 2008

A microorganism capable of producing high level of poly-3-hydoxybutyrate (PHB) from xylose was isolated from soil. The isolated strain J-65 was identified as Bacillus megaterium based on the morphological, biochemical and molecular biological characteristics. The optimum temperature and pH for the growth of B. megaterium J-65 were $37^{\circ}C$ and 8.0, respectively. The optimum medium composition for the cell growth was 2% xylose, 0.25% $(NH_4)_2SO_4$, 0.3% $Na_2HPO_4{\cdot}12H_2O$, and 0.1% $KH_2PO_4$. The optimum condition for PHB accumulation was same to the optimum condition for cell growth. Copolymer of ${\beta}$-hydroxybutyric and ${\beta}$-hydroxyvaleric acid was produced when propionic acid was added to shake flasks containing 20 g/l of xylose. Fermenter culture was carried out to produce the high concentration of PHB. In batch culture, cell mass was 9.82 g/l and PHB content was 35% of dry cell weight. PHB produced by B. megaterium J-65 was identified as homopolymer of 3-hydoxybutyric acid by GC and NMR.

• Korean Journal of Ecology and Environment
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• v.50 no.4
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• pp.381-402
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• 2017

In order to investigate distribution of vascular plants along elevational gradient in the Nodong valley of Gyebangsan, vascular plants of eight sections with 100-meter-high were surveyed from the Auto-camping site (800 m) to the top of a mountain (1,577 m). There were a total of 382 taxa: 89 families, 234 genera, 339 species, 7 subspecies, 34 varieties, and 2 forms. As a result of analyzing the pattern of species richness, it showed a reversed hump-shaped with minimum richness at mid-high elevation. As a result of analyzing habitat affinity types, the proportion of forest species increased with increasing elevation. But, the ruderal species decreased with increasing elevation, and then increased at the top of a mountain. As for the proportion of life forms, the annual herbs gradually decreased with increasing elevation, but it did not appear between 1,300 m and 1,500 m and then increased at the top of a mountain. The trees gradually increased with elevation and decreased from 1,300~1,400 m. The vascular plants divided into four groups by using DCA. The arrangement of each stands was arranged in order from right to left on the I axis according to the elevation. The distribution of vascular plants is determined by their own optimal ranges of vegetation. Also, rise in temperature due to climate change affects the distribution of vascular plants, composition, and diversity. Therefore, continuous monitoring is necessary to confirm ecological and environmental characteristics of vegetation, distribution ranges, changes of habitat. Furthermore, plans for conservation and management based on these data should be prepared according to climate change.