• 대한방사선기술학회지:방사선기술과학
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• 제16권2호
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• pp.87-94
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• 1993

In order to investigate radiation effects on the liver, functional changes of liver were analyzed after irradiation. Doses of 10 Gy, 15 Gy and 20 Gy were exposed partially to the liver of male rats(Sprague-Dawley) with X-ray(4MV linear accelerator) at room temperature. On 1, 2, 4 and 8 weeks after irradiation, liver tissues and sera of the animals were compared with those of unirradiated animal by liver function tests. Enzyme activities in sera such as alanine aminotransferase, aspartate aminotransferase, malondialdehyde. The content of malondialdehyde in the activities of many enzymes including alanine aminotransferase, aspartate aminotransferase in sera were increased slightly with increasing exposure dose in all experiments and the activities of these enzymes increased markedly in 20 Gy irradiated groups. From these above results, functional changes of the liver were induced in all irradiated groups. Damaged liver was recovered along with time collapse after irradiation to the doses of 10 Gy and 15 Gy while no recovery was deteced within 8 weeks after irradiation to 20 Gy. These results suggest that careful attention must be paid to liver not to be included in exposure field in radiation therapy.

• Corrosion Science and Technology
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• 제18권2호
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• pp.39-48
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• 2019

The feasibility of using benzotriazole (BTAH) to inhibit pitting corrosion in the sprinkler copper tubes was investigated by filling the tubes with BTAH-water solution in 829 households at an eight-year-old apartment complex. The water leakage rate was reduced by approximately 90% following BTAH treatment during 161 days from the previous year. The leakage of one of the two sprinkler copper tubes was investigated with optical microscopy, scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction analysis to determine the formation of Cu-BTA film inside the corrosion pits. All the inner components of the corrosion pits were coated with Cu-BTA films suggesting that BTAH molecules penetrated the corrosion products. The Cu-BTA film was about 2 nm in thickness at the bottom of a corrosion pit. A layer of CuCl and $Cu_2O$ phases lies under the Cu-BTA film. This complex structure effectively prevented the propagation of corrosion pits in the sprinkler copper tubes and reduced the water leakage.

• Journal of the Korean Wood Science and Technology
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• 제47권5호
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• pp.617-632
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• 2019

This study aimed to investigate the anatomical structure and fiber quality of four lesser-used wood species namely Benuang (O. sumatrana), Duabanga (D. moluccana), Pisang Merah (H. hellwigii), and Terap (A. odoratissimus). This study evaluated its suitability for raw material in pulp and paper manufacturing. The anatomical structure was observed macro- and microscopically. Macroscopic structures were observed directly to the wood samples, while microscopic characteristics were observed through microtome specimens. Fiber dimension was measured through macerated specimens and fiber quality was analyzed following the Rachman and Siagian's method. Results showed that these four timber species have similarity in the indistinct growth ring, diffuse porous in a radial pattern, rounded solitary vessel outline, 1 to 3 cells of ray width, deposits within the rays, fiber length, and cell wall thickness. Differences were found on vessel diameter, vessel grouping, vessel frequency, tyloses existence, type of axial parenchyma, and ray height. Based on fiber length and its derived values, the wood fibers of all species studied are suitable for pulp and paper manufacturing. They belong to the II quality class. The produced pulp and paper would have good quality, especially in tensile, folding, and tear strength. To promote their utilization, silviculture aspect of these four species has to be well understood.

• Advances in materials Research
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• 제11권4호
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• pp.251-277
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• 2022

Disposal of industrial waste in cities where municipal authorities permitting higher floor area ratio coupled with increasing living standards, a lot of demolition waste is being generated. Its disposal is a challenge particularly in megacities where no landfills are available. The ever-increasing cost of building construction materials also necessitates consuming demolition wastes in a useful manner to save fresh natural raw materials. In the present work, the crushed waste glass is used in high-strength concrete as a partial replacement of fine aggregate. The control concrete of grade M60 was proportioned following BIS 10262-2009. The crushed waste glass has been used as a partial replacement with varying percentages of 10, 20, 30, and 40% by weight of fine aggregate. Experimental tests were carried on the fresh and hardened state of the concrete. The effect of crushed waste glass on the workability of the concrete has been investigated. Non-destructive tests, acid attack tests, compressive strength, split tensile strength, and X-ray diffraction analysis was carried out for the control concrete and concrete containing crushed waste glass after 7, 28, and 270 days of normal curing. The results show that for the same w/c ratio, the workability of concrete increases with increasing replaced crushed waste glass content. However, the decrease in compressive strength of the concrete after 28 days of normal curing and further after 28 days of acid attacks, up to 30% replacement level of fine aggregate by the crushed waste glass is insignificant.

• Nuclear Engineering and Technology
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• 제55권1호
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• pp.156-168
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• 2023

This study investigates the high temperature oxidation behaviour of a Ni-20Cr-1.2Si (wt.%) alloy in steam from 1200 ℃ to 1350 ℃ by Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD). The results demonstrate that exposed Ni-based alloy developed a thin oxide scale, consisted mainly of Cr₂O₃. The oxidation kinetics obtained from the experimental results was applied to evaluate the hydrogen generation considering a simplified reactor core model with different cladding alloys following an unmitigated Loss-Of-Coolant Accident (LOCA) scenario in a hypothetical Small Modular Reactor (SMR). Overall, experimental data and simulations results show that both Fe-based and Ni-based alloys may enhance cladding survivability, delaying its melting, as well as reducing hydrogen generation under accident conditions compared to Zr-based alloys. However, a substantial neutron absorption occurs when Ni-based alloys are used as cladding for current uranium-dioxide fuel systems, even when compared to Fe-based alloys.

• 식품보건융합연구
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• 제8권1호
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• pp.17-20
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• 2022

Paralytic ileus is a metabolic state in which the intestines fail to transmit peristalsis due to failure of the neuromuscular mechanism in the small intestines and colon. It is a major cause of morbidity in hospitalized patients especially during late presentations and points of mismanagement. The causes include infections, electrolyte imbalance (hypokalemia, hyponatremia), surgeries and medications. When the exact cause of the disease condition is identified and corrected, paralytic ileus is usually resolved. This case report is that of a 16 year old female who was admitted and managed as a case of paralytic ileus. The patient presented with symptoms of fever, abdominal pain, abdominal distension, vomiting and inability to pass stool or flatus. There was associated body weakness, reduced urine output and weight loss. She was properly examined clinically and sent for various investigations. Investigations such plain abdominal X-Ray, serum electrolyte estimation, chest X-Ray and full blood count were carried out. The results of the investigations done were in keeping with the diagnosis of paralytic ileus, electrolyte imbalance and ongoing sepsis. She was subsequently managed through nil per oral, adequate fluid rehydration, antibiotics and correction of electrolyte imbalance. Following stable clinical state and investigation results, she was discharged and advised on follow-up.

• Journal of Korean Neurosurgical Society
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• 제60권6호
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• pp.749-754
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• 2017

Objective : To quantitatively measure the degree of bone flap resorption (BFR) following autologous bone cranioplasty and to investigate factors associated with BFR. Methods : We retrospectively reviewed 29 patients who underwent decompressive craniectomy and subsequent autologous bone cranioplasty between April 2005 and October 2014. BFR was defined as : 1) decrement ratio ([the ratio of initial BF size/craniectomy size]-[the ratio of last BF/craniectomy size]) >0.1; and 2) bone flap thinning or geometrical irregularity of bone flap shape on computed tomographic scan or skull plain X-ray. The minimal interval between craniectomy and cranioplasty was one month and the minimal follow-up period was one year. Clinical factors were compared between the BFR and no-BFR groups. Results : The time interval between craniectomy and cranioplasty was $175.7{\pm}258.2$ days and the mean period of follow up was $1364{\pm}886.8$ days. Among the 29 patients (mean age 48.1 years, male : female ratio 20 : 9), BFR occurred in 8 patients (27.6%). In one patient, removal of the bone flap was carried out due to severe BFR. The overall rate of BFR was $0.10{\pm}0.11$ over 3.7 years. Following univariate analysis, younger age ($30.5{\pm}23.2$ vs. $54.9{\pm}13.4$) and longer follow-up period ($2204.5{\pm}897.3$ vs. $1044.1{\pm}655.1$) were significantly associated with BFR (p=0.008 and 0.003, respectively). Conclusion : The degree of BFR following autologous bone cranioplasty was 2.7%/year and was associated with younger age and longer follow-up period.

• 동의생리병리학회지
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• 제20권6호
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• pp.1477-1484
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• 2006

This experimental study was designed to investigate the effects of Acanthopanax sessiliflorus $S_{EEM}$ extracts following gamma-ray irradiation on the change of weight, the serum total cholesterol, HDL-cholesterol, LDL-cholesterol, triglyceride, free fatty acid, total lipid, phospholipid level in obese mice induced by high fat diet, and the change of regional cerebral blood flow (rCBF) and blood pressure (BP) in normal rats. Experimental materials were as follows ; 10AS was the bark powder of Acanthopanax sessiliflorus $S_{EEM}$ stems which was exposed in 10 kGy electron beam, 10AS was the bark powder of Acanthopanax sessiliflorus $S_{EEM}$ roots which was exposed in 10 kGy electron beam, 100S was the bark powder of Acanthopanax sessiliflorus $S_{EEM}$ stems which was exposed in 100 kGy electron beam, Experimental groups were as follows ; Normal group was fed with normal diet and administered with distilled water during 5 weeks, Control group was fed with high fat diet and administered with distilled water during 5 weeks, Sample A group was fed with high fat diet and administered with 10AS of 300 mg/kg/mouse/day during 5 weeks, Sample B group was fed with high fat diet and administered with 10AR of 300 mg/kg/mouse/day during 5 weeks, Sample C group was fed with high fat diet and administered with 100AS of 300 mg/kg/mouse/day during 5 weeks. The results were as follows ; Sample A group, Sample B group and Sample C group were significantly decreased body weight and the serum LDL-cholesterol, triglyceride, total lipid level in comparison with Control group. Sample A group, Sample B group and Sample C group were significantly increased the serum HDL-cholesterol level in comparison with Control group. Sample B group and Sample C group were significantly decreased the serum total cholesterol, free fatty acid and phospholipid level in comparison with Control group. This results were suggested that all experimental materials were able to be used for the obesity. 10AS did not changed rCBF and MABP in a dose-dependent manner. 10AR significantly increased rCBR in a dose-dependent manner, and BP did not change in a dose-dependent manner. 100AS decreased rCBF and BP in a dose-dependent manner. This results were suggested that 10 AR significantly increased rCBF by dilating pial arterial diameter. According to above results, the authors suggested that 10AR was able to be used for the obesity and ischemic disease.

• Journal of Preventive Medicine and Public Health
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• 제7권1호
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• pp.123-130
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• 1974

A socio-medical survey was carried out on 1,108 cases of pulmonary tuberculosis who had registered and 220 cases unregistered at Jeonju health center in 1973, during from June 1 to July 31, 1974. As the results of this survey, the following conclusions were obtained. 1. Of the total 1,108 cases of pulmonary tuberculosis there were 708 new cases, while remaining 400 were old cases and rate of registration was 4.0 per thousand person. 2. The highest rate of registration of the newly diagnosed pulmonary tuberculosis could be found in bacteriological examination while 54.4 per cent in X-ray examination. 3. As for the educational status of the tuberculosis patients, primary school graduates contituted the greatest proportion or 64.6 per cent, middle school graduates 13.6 per cent, high school graduates 6.8 per cent and collge graduates only 0.7 per cent. 4. By age group of the cases, at age of 20 to 29 years occupied 23.6 per cent (262 out of 1,108 cases), 17.9 per cent at age of 40 to 49 years. 5. The greatest proportion or 38.4 per cent of the cases had no occupation. 6. The living standard of the patient's household, low class constituted 60.6 per cent of the total households. 7. By distribution of residential area, farming area was 5.0 per thousand person, 4.0 in downtwon and suburban areas. 8. The greatest proportion or 70.0 per cent of positive cases in X-ray examination was unregistered in August, 63.6 per cent in July 1973. 9. 220 out of 1,108 cases(19.9%) were unregistered pulmonary tuberculosis in X-ray and bacteriological examinations. 10. For age groups of unregistered caes, most prevalent age group was 30 to 39. 11. Regarding on the cases of unregistration, 'indifference for disease' occupied highest rate with 31.9 percent' and 'private secret' with 15.7 per cent. 12. Of the total 457 cases drop-outed, there were 78 complete heald cases while remaining 207 inactive.

• 천문학회지
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• 제21권1호
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• pp.79-95
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• 1988

To examine relations between stellar activity and rotation we estimated parameters of stellar activity such as $R'_{HK}$, $R'_{MgII}$, $R'_{CII}$, $R'_{CIV}$ and $R'_{X-ray}$ from the published data which measure the activity levels of stellar chromospheres, transition regions and coronae. In the present study we considered only the main sequence stars in an attempt to minimize the influence of other stellar parameters such as radius, age and stellar convection on stellar activity since they are also known to affect the magnetic field generation. In the present analysis we selected only those stars that satisfy the following conditions: (1) flux measurements are available together with Ca II fluxes and (2) rotation periods are determined by Ca II observations. We derived relations between the ${\bar{R}}ossby$ number $R_o$ and stellar activity $R'_{HK}$, $R'_{MgII}$, $R'_{CII}$, $R'_{CIV}$ and $R'_{X-ray}$ and assessed the relations by plotting $R'_{HK}$, $R'_{MgII}$ and $R'_{X-ray}$ against rotation period $P_{rot}$ for comparison with observations. From the comparison it is found that as far as the rotation-activity relation is concerned, (1) normalized surface flux $R'_{HK}$ is better than the surface flux $F'_{HK}$, in the sense that $R'_{HK}$ differentiates the color dependence better and (2) $R'_{HK}$ defined by Rutten (1984) describes the observations notably better than $R'_{HK}$ of Noyes et al. (1984).