• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.41-44
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• 2010

Purpose: Along with recent advances in PET/CT instrumentation and imaging technology, the number of patients has also been steadily increasing. This resulted in the increased radiation exposure to radiation workers in PET/CT rooms. In this study, we installed a radiation shield and investigated whether it could reduce radiation exposure to the workers and thus enhance job satisfaction. Materials and Methods: A radiation shield is composed of 5 cm thick lead and has a structure in which a radiation worker sits and watches a patient through lead glass while injecting radiopharmaceutical to the patient. Quarterly absorbed dose of radiation workers was measured using thermoluminescence dosimeters (TLD) and the results were compared for six months each before and after installation of the radiation shield. Exposure dose was also measured using a pocket dosimeter placed at the same location in the front and the back of the radiation shield. In addition, frequency of use of the shield and job satisfaction of radiation workers were investigated using a survey. Results: Quarterly absorbed dose of radiation workers was 2.70 mSv on average before installation of new radiation shield, whereas that dropped to 2.13 mSv after installation of radiation shield, reducing radiation exposure dose by 21%. Exposure dose on the front side of the shield was 61.2 R, whereas that on the back side of shield was 2.8 R. According to the survey, 85% of workers used the shield and were satisfied with the outcome: each radiation worker made injections to patients average of 6.5 times/day and preferred sitting to standing while injecting radiopharmaceutical to patients. Conclusion: Use of radiation shield reduced the exposure dose of radiation workers, which is the ultimate goal of radiation protection to minimize radiation exposure and is an appropriate method for the improvement of hospital working environment. Furthermore, we found that use of radiation shield not only relieves physical and psychological burden of radiation workers but also enhances job satisfaction. This result indicates that use of radiation shield is important for improvement of the radiation workers' job environment in terms of radiation protection.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.104-109
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• 2010

Purpose: $[^{18}F]$Fallypride plays an effective radiotracer for the study of dopamine $D_2/D_3$ receptor occupancy, neuropsychiatric disorders and aging in humans. This tracer has the potential for clinical use, but automated labeling efficiency showed low radiochemical yields about 5~20% with relatively long labelling time of fluorine-18. In present study, we describe an improved automatic synthesis of [$^{18}F$]Fallypride using different base concentration for routine clinical use. Materials and Methods: Fully automated synthetic process of [$^{18}F$]Fallypride was perform using the TracerLab $FX_{FN}$ synthesizer under various labeling conditions and tosyl-fallypride was used as a precursor. [$^{18}F$]Fluoride was extracted with various concentration of $K_{2.2.2.}/K_2CO_3$ from $^{18}O$-enriched water trapped on the ion exchange cartridge. After azeotropic drying, the labeling reaction proceeded in $CH_3CN$ at $100^{\circ}C$ for 10 or 30 min. The reaction mixture was purified by reverse phase HPLC and collected organic solution was exchanged by tc-18 Sep-Pak for the clinically available solution. Results: The optimal labeling condition of [$^{18}F$]Fallypride in the automatic production was that 2 mg of tosyl-fallypride in acetonitrile (1 mL) was incubated at $100^{\circ}C$ for 10 min with $K_{2.2.2.}/K_2CO_3$ (11/0.8 mg). [$^{18}F$]Fallypride was obtained with high radiochemical yield about $66{\pm}1.4%$ (decay-corrected, n=28) within $51{\pm}1.2$ min including HPLC purification and solid-phase purification for the final formulation. Conclusion: [$^{18}F$]Fallypride was prepared with a significantly improved radiochemical yield with high specific activity and shorten synthetic time. In addition, this automated procedure provides the high reproducibility with no synthesis failures (n=28).

• The Korean Journal of Nuclear Medicine
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• v.32 no.6
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• pp.482-489
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• 1998

Purpose: Radionuclide cisternography may be helpful in understanding pathophysiology of postural head-ache and low CSF pressure in patients with spontaneous intracranial hypotension. The purpose of this study was to characterize radionuclide cisternographic findings of spontaneous intracranial hypotension. Materials and Methods: The study population consists of 15 patients with spontaneous intracranial hypotension. Diagnosis was based on their clinical symptoms and results of lumbar puncture. All patients underwent radionuclide cisternography following injection of 111 to 222 MBq of Tc-99m DTPA into the lumbar subarachnoid space. Sequential images were obtained between 112 hour and 24 hour after the injection of Tc-99m DTPA. Radioactivity of the bladder, soft tissue uptake, migration of radionuclide in the subarachnoid space, and extradural leakage of radionuclide were evaluated according to the scan time. Results: Radionuclide cisternogram showed delayed migration of radionuclide into the cerebral convexity (14/15), increased soft tissue uptake (11/15), and early visualization of bladder activity at 30min (6/10) and 2hr (13/13). Cisternography also demonstrated leakage site of CSF in 4 cases and 2 of these were depicted at 30min. Epidural blood patch was done in 11 patients and headache was improved in all cases. Conclusion: The characteristic findings of spontaneous intracranial hypotension were delayed migration of radionuclide and early visualization of the soft tissue and bladder activity. These scintigraphic findings suggest that CSF leakage rather than increased CSF absorption or decreased production may be the main pathophysiology of spontaneous intracranial hypotension. Early and multiple imaging including the bladder and soft tissue is required to observe the entire dynamics of radionuclide migration.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.4
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• pp.294-300
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• 2010

Purpose: The template-guided implant surgery offers several advantages over the traditional approach. The purpose of this study was to evaluate the accuracy of coordinate synchronization procedure with 5-axis milling machine for surgical template fabrication by means of reverse engineering through universal CAD software. Materials and methods: The study was performed on ten edentulous models with imbedded gutta percha stoppings which were hidden under silicon gingival form. The platform for synchordination was formed on the bottom side of models and these casts were imaged in Cone beam CT. Vectors of stoppings were extracted and transferred to those of planned implant on virtual planning software. Depth of milling process was set to the level of one half of stoppings and the coordinate of the data was synchronized to the model image. Synchronization of milling coordinate was done by the conversion process for the platform for the synchordination located on the bottom of the model. The models were fixed on the synchordination plate of 5-axis milling machine and drilling was done as the planned vector and depth based on the synchronized data with twist drill of the same diameter as GP stopping. For the 3D rendering and image merging, the impression tray was set on the conbeam CT and pre- and post- CT acquiring was done with the model fixed on the impression body. The accuracy analysis was done with Solidworks (Dassault systems, Concord, USA) by measuring vector of stopping’s top and bottom centers of experimental model through merging and reverse engineering the planned and post-drilling CT image. Correlations among the parameters were tested by means of Pearson correlation coefficient and calculated with SPSS (release 14.0, SPSS Inc. Chicago, USA) ($\alpha$ = 0.05). Results: Due to the declination, GP remnant on upper half of stoppings was observed for every drilled bores. The deviation between planned image and drilled bore that was reverse engineered was 0.31 (0.15 - 0.42) mm at the entrance, 0.36 (0.24 - 0.51) mm at the apex, and angular deviation was 1.62 (0.54 - 2.27)$^{\circ}$. There was positive correlation between the deviation at the entrance and that at the apex (Pearson Correlation Coefficient = 0.904, P = .013). Conclusion: The coordinate synchronization 5-axis milling procedure has adequate accuracy for the production of the guided surgical template.

• Journal of Chest Surgery
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• v.31 no.10
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• pp.964-972
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• 1998

Background: The purpose of this study was to independently evaluate the beneficial effects of a high dose of transamine administrated prior to CPB on the postoperative hematologic aspect and bleeding. Materials and methods: This study included randomly selected groups of 40 adult patients undergoing OHS with CPB. All patients were divided into 2 groups: transamine group (T-group, n=20) and placebo group(P-group, n=20). The T-group received a high-dose of transamine(10 g) before and during CPB. The P-group received normal saline at the same times and served as a control group. Results: The results of comparative studies between the 2 groups in the same hematologic variables were summarized as follows. \circled1 During CPB, the fibrinogen concentrations and platelet counts were significantly lower in the P-group than in the T-group(p<0.01). \circled2 During CPB, production of D-dimer occurred in 18 patients(90%) in the P-group and did not occur in the T-group(0%) (p<0.0001). \circled3 At CPB-off, the % concentration of fibrinogen(70.2$\pm$3.9%) and the % platelet counts(72.4$\pm$4.5%) of the T-group were significantly higher than those(54.5$\pm$3.8%, 64.3$\pm$2.9%) of the P-group(p<0.01). \circled4 Postoperative values of PT(14.0$\pm$0.03 sec.) and aPTT (27.6$\pm$0.1 sec.) of the T-group were significantly lower than those(16.0$\pm$0.02sec., 30.1$\pm$0.1sec.) of the P-group(p<0.05). \circled5 Postoperative bleeding and requirement of whole blood and other blood products were significantly less in the T-group than in the P-group(p <0.05). \circled6 There were no significant hypercoagulability signs such as cerebral em bolism, myocardial infarction, pulmonary embolism, or any other neurological prob lems in either group. Conclusions: We concluded that a high dose of transamine administered prior to CPB prevents the activation of fibri nolytic system and has beneficial effects of reducing the postoperative bleeding t endency without apparent hypercoagulability signs.

• Microbiology and Biotechnology Letters
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• v.8 no.3
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• pp.199-206
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• 1980

Some experiments on the citric acid production were carried out from soluble starch and molasses as raw materials. When soluble starch was used as substrate for the fermentation of citric acid by the strain M-80 which had assimilating ability of soluble starch in surface culture, the optimal culture media was 120g of soluble starch, 3.0g of (N $H_4$)$_2$S $O_4$, 2.0g of K $H_2$P $O_4$, 0.2g of MgS $O_4$.7$H_2O$, 1.5mg of F $e^{++}$, 1mg of Z $n^{++}$ and 20ml of methanol were added to 1 liter and optimal pH was 5.5. In about 8 days 61.8mg/ml of citric acid was produced. When treated molasses with potassium ferrocyanide was used as substrate for the fermentation of citric acid by the strain of M-315, the optimal condition in surface culture was 250g of molasses, 0.3g of N $H_4$N $O_3$, 0.05g of K $H_2$P $O_4$, 0.01g of MgS $O_4$.7$H_2O$, 0.5g of Potassium ferrocyanide and 30ml of methanol were added to 1.0 liter. On the other hand, the optimal condition in submersed culture was 250g of molasses, 0.3g of N $H_4$N $O_3$, 0.1g of K $H_2$P $O_4$, 0.01g of MgS $O_4$.7$H_2O$, 0.5g of potassium ferrocyanide, and 30m1 of methanol were added to 1.0 liter and optimal pH was all 5.0. After 9 days culture, 69.4mg/ ml, 39.6mg/ml of citric acid were separately produced in surface and submerged culture media.dia.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1086-1093
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• 2012

This research was carried out to develop the correction method of VDI4630 method improving accuracy, and investigated the effects of carbonate ion ($CO_3{^{2-}}$) and reactant water ($H_2O$) on anaerobic organic biodegradability in VDI4630 method. Pig blood, pig intestine residue, pig digestive tract content, and cattle rumen content were experimented as waste biomasses. Chemical formulas of pig blood, pig intestine residue, pig digestive tract content, and cattle rumen content were $C_{3.78}H_{8.39}O_{1.46}N_1S_{0.01}$, $C_{9.69}H_{15.42}O_{2.85}N_1S_{0.03}$, $C_{25.17}H_{43.32}O_{15.04}N_1$, $C_{27.23}H_{42.38}O_{15.93}N_1S_{0.11}$, respectively. And amount of reactant moisture for the anaerobic degradation of organic materials were 0.336, 0.485, 0.227, 0.266 mol, respectively. In pig blood, pig intestine residue, pig digestive tract content, and cattle rumen content, anaerobic organic biodegradability presented as $B_u/B_{th}$ were 82.3, 81.5, 70.8, and 66.1%, and anaerobic organic biodegradability (AB) by VDI4630 method were 72.2, 87.8, 74.2, 62.0%, and that were significantly different with anaerobic organic biodegradability presented as $B_u/B_{th}$. The effects of carbonate ion and reactant water on anaerobic organic biodegradability were not significant, But Accuracy of anaerobic organic degradability was expected to able to be improved by the correction method of VDI4630 considering the carbonate ion at digestate and the reactant water quantified.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.4
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• pp.267-273
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• 1977

Rainbow trout were reared in a small indoor aquarium which was equipped with a simple recirculating biofilter combined with a small amount of inflowing water for 199 days from April 25 to November 10, 1977 in Busan where very hot summer air temperature is encountered, and results obtained were promissing as following; 1. The aquarium has dimensions of $1m\;\times\;1m\;\times\;67cm(depth)$, and a bottom center sedimentation chamber of conical type through which out-flowing water is pushing fecal matter and other detritus outward. The conical sedimentation chamber measures 20 cm depth and 20 cm diameter at its upper mouth and tapers to the bottom end which is connected to 4 cm diameter draining pipe. The draining pipe goes through under the tank and then is elevated on the side. The water depth was maintained at about 40 cm depth by adjusting the heigh of draining pipe. The filter bed contained 16 l of $3\~5\;mm$ zeolite gravels, and water circulation rate was about 1030 l/hr. 2. Continuous inflowing water resulted in a good elimination of waste materials through its outflowing water thus reducing waste loading in the filter. 3. Mean temperature of water in the rearing aquarium containing about 400 l water volume was maintained at around 20 to $22^{\circ}C$ by 0.59 l/min of the inflowing well water which usually maintained the temperature of $17^{\circ}C$ during the hot summer season from the first of July to the first of October when the 10-days-mean air temperature ranged from $20^{\circ}\;to\;27.3^{\circ}C$ $(total\;mean\;24.6^{\circ}C) $ and under this condition the fish continued normal growth. 4. The production per 1 l/min of inflowing water with this simple biofilteration reached 30 hg. 5. The total cost including all feed and power during this experimental rearing period fell well within the economic establishment and if the feed and filteration system are improved the benefit-cost ratio will be much increased.

• The Korean Journal of Malacology
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• v.27 no.4
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• pp.359-369
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• 2011

Twelve species of food microalgae were investigated to clarify the digestion index of Crassostrea gigas larvae using epifluorescence microscopy to choose an appropriate diet for artificial seed production in hatchery. An experiment was conducted using 1 (D shaped stage), 4 (Early umbo stage), 8 (umbo stage) and 12 (Full grown stage) days old larvae. larvae were stocked in 1 L flasks at 5 individuals/mL and fed $10{\times}10^4$ algal cells/mL of each species individually. Prior to larvae were fed for 3 h and then were observed under the microscope to detect ingestion; larvae were then sieved and replaced in 1 L flasks containing filtered seawater and were observed after 3, 5 and 8 h to analyse the digestion index. Values of digestion indices were specific for each alga. No evidence for the ingestion of Thalassiosira weissflogii was evident at all larval development stages tested. Digestion indices of others microalgae were 0.8-99.7% at 4 stage of larval development stages: Chlorella ellipsoidea (0.8-5.4%), Nannochloris oculata (1.4-5.0%), Isochrysis galbana (99.1-99.5%), Pavlova lutheri (99.1-99.5%), I. aff. galbana (99.4-99.5%), Cheatoceros calcitrans (0.0-99.2%), C. gracilis (0.0-99.7%), C. simplex (0.0-95.9%), Phaeodactylum tricornutum (0.0-99.6%), Tetraselmis tetrathele (0.0-99.7%) and Dunaliella tertiolecta (0.0-99.6%), respectively. Therefore, it is assumed that food microalgae showing the high digestion such as I. galbana should be supplied to the early umbo stage larvae, and then after the umbo larval stage, the mixed microalgae with diatoms and light green algae should be supplied to the full grown stage larvae to increase the digestion of their larvae.

• Applied Biological Chemistry
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• v.23 no.3
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• pp.157-165
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• 1980

Kojis were prepared from the different starch raw materials such as glutinous rice, barley rice, wheat flour and sweet potato, and were tested in an effort to reduce production cost and to improve quality of Kochuzang(red pepper paste). During the starting period of Koji preparation, there were less significant changes in pH; however, pH decreased somehow in the case of sweet potato, whereas it increased for the other Kojis. In general, the highest acidity was obtained after 72 hours of Koji preparation. Total nitrogen, soluble nitrogen and amino-nitrogen content increased in order of wheat flour, barley rice, and glutinous rice; Kojis they were markedly produced between 72 and 96 hours of Koji preparation. The maximum amount of reducing sugar was observed between 48 and 72 hours of Koji preparation during this period the reducing sugar content varied widely depending on starch source. Sweet potato Koji produced the highest level of ethyl alcohol content after 72 hours of Koji preparation; for the other Koji the same trends were observed after 24 hours. The starch liquefying activities have reached the highest level after 96 hours and for glutinous rice and barley rice; however, they kept on increasing until 120 hours for wheat flour and sweet potato. Koji Starch liquefying and saccharogenic amylase activities tended to increase in order of sweet potato, glutinous rice, barley rice and wheat flour. Kojis Various protease activities were measu-red during the Koji preparation, and they increased in order of alkali, neutral and acidic protease.