• The Korean Journal of Nuclear Medicine
• /
• v.31 no.3
• /
• pp.320-329
• /
• 1997

Neuroanatomic substrate of autism has been the subjects of continuing investigation. Because previous studies had not demonstrated consistent and specific neuroimaging findings in autism and most studies comprised adults and school-aged children, we performed a retrospective review in search of common functional and anatomical abnormalities with brain SPECT using Tc-99m ECD and correlative MRI The patient population was composed of 18 children aged 28 to 89 months(mean age : 55 months) who met the diagnostic criteria of autism as defined in the DSM-IV and CARS. Brain SPECT was performed after intravenous injection of 185-370MBq of Tc-99m ECD using brain dedicated annular crystal gamma camera. MRI was performed in all patients including T1, T2 axial and T1 sagittal sequences. SPECT data were visually assessed. Thirteen patients had abnormal SPECT scan revealing focal areas of decreased perfusion. Decreased perfusion of cerebellar vermis(12/18), cerebellar hemisphere(11/18), thalami(13/18), basal ganglia(4/18), posterior parietal(7/18), and temporal(4/18) area were noted on brain SPECT. Whereas, only 3 patients had abnormal MR findings which were subtle volume loss of parieto-occipital white matter in 3 and mild thinning of posterior body of corpus callosum in 2 and slightly decreased volume of cerebellar vermis in 1. Comparison of the numbers of abnormal findings revealed that regional cerebral blood flow (rCBF) abnormalities seen on SPECT were more numerous than anatomical abnormalities seen on MRI. In conclusion, extensive perfusion impairment involving cerebellum, thalami and parietal lobe were found in this study. SPECT may be more sensitive in reflecting pathophysiology of autism than MRI. However, further studies are mandatory to determine the significance of thalamic and parietal perfusion impairment in autism.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.18 no.1
• /
• pp.115-121
• /
• 2014

Purpose: In addition to improving the quality of the PET image, through much research, the development of various programs are performed. Astonish TF reconstruction techniques by Philips can confirm the improved contrast of the lesion. Also, It's image reconstruction of 2 mm is possible with rapid reconstruction rate than conventional. In this study, we compared and evaluated Standardized Uptake Value (SUV) in accordance with the 2 mm reconstruction techniques and traditional 4 mm from the $^{18}F-FDG$ PET whole body image. Materials and Methods: In the phantom experiment, NEMA IEC body phantom (sphere: 10, 13, 17, 22, 28, 37 mm) was used to obtain images by using GEMINI TF 64 PET/CT (Philips, Cleveland, USA). Also, In the clinical images, we performed $^{18}F-FDG$ PET/CT examination to 30 women (age: $55.1{\pm}11.3$, BMI: $24.1{\pm}2.9$) with a diagnosis of breast cancer. After that, we reconstructed images in 2 mm and 4 mm respectively. The region of interest was drawn to acquired images. Since then, we measured SUV and statistically analyzed with SPSS ver.18 by using EBW (Extended Brilliance Workstation) NM ver.1.0. Results: After analyzing the result of the phantom study, there was a tendency that the bigger hot sphere size, the higher SUV. If you compared the 2 mm reconstruction techniques to 4 mm, it increased 95.78% in 10 mm, 50.60% in 13 mm, 25.00% in 17 mm, 30.04% in 22 mm, 31.81% in 28 mm, and 27.84% in 37 mm. Through the result of the analysis of the 2 mm reconstruction techniques and 4 mm in clinical images, it appeared that SUV of 2 mm was higher than that of 4 mm. Also the smaller the volume was, the more the change rate increased. Conclusion: After analyzing the result of the clinical picture and phantom experiments applied by Astonish TF reconstruction techniques, as the size of the volume was small, the change rate of the SUV increased. Therefore, it was necessary to further research about the SUV correction for accurate and active utilization of 2 mm reconstruction techniques which had excellent lesion discrimination ability and contrast in clinic.

• Journal of Wetlands Research
• /
• v.16 no.4
• /
• pp.303-318
• /
• 2014

Baseflow gives a significant contribution to stream function in the regions where climatic characteristics are seasonally distinct. In this regard, variable baseflow can make it difficult to maintain a stable water supply, as well as causing disruption to the stream ecosystem. Changes in land use can affect both the direct flow and baseflow of a stream, and consequently, most other components of the hydrologic cycle. Baseflow estimation depends on the observed streamflow in gauge watersheds, but accurate predictions of streamflow through modeling can be useful in determining baseflow data for ungauged watersheds. Accordingly, the objectives of this study are to 1) improve predictions of SWAT by applying the alpha factor estimated using RECESS for calibration; 2) estimate baseflow in an ungauged watershed using the WHAT system; and 3) evaluate the effects of changes in land use on baseflow characteristics. These objectives were implemented in the Gapcheon watershed, as an ungauged watershed in South Korea. The results show that the alpha factor estimated using RECESS in SWAT calibration improves the prediction for streamflow, and, in particular, recessions in the baseflow. Also, the changes in land use in the Gapcheon watershed leads to no significant difference in annual baseflow between comparable periods, regardless of precipitation, but does lead to differences in the seasonal characteristics observed for the temporal distribution of baseflow. Therefore, the Guem River, into which the stream from the Gapcheon watershed flows, requires strategic seasonal variability predictions of baseflow due to changes in land use within the region.

• Food Science of Animal Resources
• /
• v.28 no.1
• /
• pp.69-75
• /
• 2008

This study evaluated the physicochemical and sensory characteristics of vanilla ice cream treated with gamma irradiation. The general composition of the vanilla ice cream used for the study was 45.4-53.3% moisture, 5.5-5.9% fat and 3.9-4.1% protein, and these values did not change following gamma irradiation. The Hunter L, a and b values were slightly decreased following gamma irradiation. The fatty acid composition of the ice cream included caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid and stearic acid, and there was no detectable change following irradiation. There was no significant difference in TBARS (2-thiobarbituric acid reactive substances) values between non-irradiated and irradiated samples at a dose of 3 kGy or less (p<0.05). Sensory evaluation indicated that gamma-irradiated vanilla ice cream did not show any difference in color relative to non-irradiated ice cream. However, gamma irradiation did affect the flavor, taste and overall acceptability of ice cream at doses above 3 kGy. These results indicate that gamma irradiation at 3 kGy is an effective treatment for sustaining the physicochemical characteristics of vanilla ice cream with minimal changes in sensory characteristics, though further studies should be carried out to reduce the deterioration of sensory qualities induced by gamma irradiation.

• Journal of Chest Surgery
• /
• v.40 no.8
• /
• pp.546-551
• /
• 2007

Background: The radial artery is gaining widespread acceptance as complementary arterial conduits for surgical myocardial revascularization, but there have been limited reports about its angiographic patency compared with that of internal thoracic artery or saphenous vein. We tried to evaluate angiographic patency of radial artery graft and to compare that of radial artery and other gratis with retrospective manner. Material and Method: From January 2001 to Jure 2006, totally 132 patients (male 92, female 40) who underwent coronary artery bypass graft using radial artery were re-admitted to our hospital for follow up angiographic examination. Mean age was 58.2+8.87 and mean follow up duration was 32 month ($2{\sim}110$ month). Off pump and on pump bypass surgery were performed 74 and 58 patients respectively. Along with radial artery, left internal thoracic arteries were used in 57 cases, concomitant left internal thoracic artery and saphenous veins were used in 47 cases and bilateral internal thoracic arteries were used in 20 cases. Result: Totally 412 distal anastomosis were performed and 376 anastomosis remained patent (91.2%). Left internal thoracic artery showed the most excellent patency in all of the conduits (98.5%). Radial artery graft patency was 90.8% (169/186). There was no statistical difference of the patency by conduit between on-pump and off-pump group. But radial artery showed more higher patency rate (98/110, 89%) in the severe stenotic lesion that preoperatively revealed more than 90% stenosis than in the lesser severe (<90%) stenotic lesion (60/76, 78%)(p < 0.005). Radial artery conduit represented the worst result when it was grafted in the right coronary system. But when it was positioned in the left heart especially diagonal or obtuse marginal area, patency was comparable with left internal thoracic artery. Conclusion: Radial artery graft showed good midterm patency when it was used in the severe stenotic lesion more than 90% and left coronary system. But great notice should be taken when it is grafted in the right coronary system or less severe stenotic lesion.

• Journal of the Mineralogical Society of Korea
• /
• v.26 no.4
• /
• pp.245-262
• /
• 2013

We analyzed 29 surface sediment samples in five submarine volcanoes (TA12, TA19, TA22, TA25, and TA26) located in the southern part of the Tonga arc for trace elements and rare earth elements to investigate characteristics of the hydrothermal alteration of surface sediments. Based on analytical results of trace element and rare earth element (REE), surface sediments of TA12, TA19, and TA22 submarine volcanoes, which are located in the northern part of the study area, were very little or not influenced by hydrothermal fluids. In contrast, some stations of TA25 and TA26 submarine volcanoes were strongly affected by hydrothermal fluids. However, these two submarine volcanoes showed different features in element concentration in the sediments. Some stations of TA25 submarine volcano showed enrichment of Ni, Cu, Sn, Zn, Pb, Cr, Cd, Sb, W, Ba, Ta, Rb, Sr, and As, however, those of TA26 submarine volcano showed enrichment of Sn, Zn, Pb, Cd, Sb, Ba, Rb, and Sr. Stations which enriched trace elements were observed, enriched REEs were also observed. Average upper continental crust (UCC)-normalized REE patterns of the surface sediments generally showed low light REE (LREE) abundances and increased heavy REE (HREE) abundances. Eu enrichment was identified at several stations of TA25 and TA26 submarine volcanoes. In addition, enrichment of Ce was found at some stations of TA26 submarine volcano and these enrichment patterns were similar with hydrothermal fluid of near stations. Furthermore, TA25 and TA26 submarine volcanoes showed different enrichment characteristics of trace elements and REE. Trace elements were concentrated at TA25 submarine volcano. TA26 submarine volcano, on the other hand, observed highly enrichment of REE especially, Eu and Ce. As a result of the investigation, the characteristics and concentrations of REEs and trace elements in the surface sediments of each submarine volcano can be applied to identify hydrothermal alteration of sediments during exploration for hydrothermal deposits.

• Korean Journal of Microbiology
• /
• v.51 no.2
• /
• pp.97-107
• /
• 2015

Wetlands constitute a transitional zone between terrestrial and aquatic ecosystems and have unique characteristics such as frequent inundation, inflow of nutrients from terrestrial ecosystems, presence of plants adapted to grow in water, and soil that is occasionally oxygen deficient due to saturation. These characteristics and the presence of vegetation determine physical and chemical properties that affect decomposition rates of organic matter (OM). Decomposition of OM is associated with activities of various extracellular enzymes (EE) produced by bacteria and fungi. Extracellular enzymes convert macromolecules to simple compounds such as labile organic carbon (C), nitrogen (N), phosphorus (P), and sulfur (S) that can be easily taken up by microbes and plants. Therefore, the enzymatic approach is helpful to understand the decomposition rates of OM and nutrient cycling in wetland soils. This paper reviews the physical and biogeochemical factors that regulate extracellular enzyme activities (EEa) in wetland soils, including those of ${\beta}$-glucosidase, ${\beta}$-N-acetylglucosaminidase, phosphatase, arylsulfatase, and phenol oxidase that decompose organic matter and release C, N, P, and S nutrients for microbial and plant growths. Effects of pH, water table, and particle size of OM on EEa were not significantly different among sites, whereas the influence of temperature on EEa varied depending on microbial acclimation to extreme temperatures. Addition of C, N, or P affected EEa differently depending on the nutrient state, C:N ratio, limiting factors, and types of enzymes of wetland soils. Substrate quality influenced EEa more significantly than did other factors. Also, drainage of wetland and increased temperature due to global climate change can stimulate phenol oxidase activity, and anthropogenic N deposition can enhance the hydrolytic EEa; these effects increase OM decomposition rates and emissions of $CO_2$ and $CH_4$ from wetland systems. The researches on the relationship between microbial structures and EE functions, and environmental factors controlling EEa can be helpful to manipulate wetland ecosystems for treating pollutants and to monitor wetland ecosystem services.

• Korean Journal of Microbiology
• /
• v.44 no.3
• /
• pp.178-185
• /
• 2008

Avian influenza virus (AIV) is recognized as key to the emergence of pandemic influenza for humans; there are growing concerns that AIV H9N2 may become more efficient to transmit to humans in the near future, since the infection of poultry with AIV H9N2 has been common in recent years. In this study, we aimed to produce antisera recognizing the HA and NA proteins of AIV H9N2. Initially, coding sequences corresponding to the N-terminal regions of the HA and NA proteins of the Korean AIV H9N2 (A/Ck/Kr/MS96/96) isolated from a domestic chicken were amplified from the genomic RNA. Following cloning of the amplified cDNA fragments into pGEX4T-1 vector, two GST-fusion proteins (GST-HAln and GST-NAn) were expressed in E. coli BL21 and purified with glutathione sepharose columns; the recombinant GST-HAln and GST-NAn proteins were both used as immunogens in rabbits. The antigenicity of the rabbit antisera was analyzed by immunoblotting of the cell lysates prepared from AIV H9N2-infected MDCK cells. Overall, the recombinant HAln and NAn proteins fused to the C-terminus of GST and the rabbit antisera raised against the corresponding recombinant proteins would provide a valuable reagent for AIV diagnosis and basic research.

• The Korean Journal of Mycology
• /
• v.24 no.1 s.76
• /
• pp.56-66
• /
• 1996

Ecological variations of Arbuscular mycorrhizal (AM) fungi were determined from the soils collected from different sites of the polluted and unpolluted areas related to the soil pollutions. Average 24.5 spores $(per\;20g)^{-1}$ soil of AM fungal spore were counted from the 32 sites of soils collected from On-san (polluted), whereas average 4.1 spores $(per\;20g)^{-1}$ soil from the 18 sites of those from Mt. Kwanak (polluted); Average 23.6 spores $(per\;20g)^{-1}$ soil of AM fungal spore were also counted from the 30 sites of soils collected from Chung-mu (unpolluted), whereas average 15.8 spores $(per\;20g)^{-1}$ soil from the 14 sites of those from Mt. Chungwang (unpolluted).The spores of AM fungi were the species of Glomus, Gigaspora, Acaulospora and Scutellospora. Among the above four genera, the species of Glomus were observed to be more abundant than the other genera in the soils collected from On-san, Chung-mu and Mt. Chungwang whereas the species of Gigaspora in those from Mt. Kwan-ak. The parameters of soils measured showed some variations between the polluted and unpolluted areas; 12.9 to 16.4% in the soil moisture, 5.6 to 8.3% in the organic matter and 4.3 to 5.7 at soil pH (polluted to unpolluted areas, respectively). The soils collected, thereby, appeared to be more strongly acidic and also lower in the contents of soil moisture or organic matter at the polluted area than unpolluted area. Based on the ecological criteria, the species richness or species diversity had significant differences (p<0.05) between polluted and unpolluted area. The spore density of genus Glomus or Gigaspora was significantly different (p<0.05) among the soils of three different plant vegetations (conifer plants, broad leaf plants, and grass plants). Also, there were significant differences (p<0.05) in the species evenness or species diversity among the soils referring to three different plant vegetations. There was a direct relationship $(r^2=0.38)$ between soil moisture and organic matter measured from 94 soil samples. Since there was a direct relationship $(r^2=0.22)$ between organic matter and total spores, it seems to be likely to presume that mycorrhizal spores can be increased in proportion to enhanced organic matters in soils. The species richness or species diversity was inclined to increase in proportion to enhanced soil pH and total spores in soils.

• Journal of Animal Science and Technology
• /
• v.53 no.5
• /
• pp.441-450
• /
• 2011

This study was conducted to determine the effects of partial replacement of corn grain and soybean meal with agricultural by-product feeds on in vitro rumen fermentation characteristics and optimum levels of mixing ratio. The agricultural by-products to examine the effectiveness of the partial replacement of concentrate were wheat bran, corn gluten feed, bakery waste, soybean curd, rice bran, green kernel rice, soybean hull, distillers' grain, and mushroom substrate. In the first experiment, in vitro ruminal fermentation characteristics of feedstuffs were evaluated at 0, 3, 6, 12, 24, and 48 hours after incubation. In the second experiment, fermentation characteristics were investigated with green kernel rice and soybean curd which replaced corn grain or soybean meal. Feed were formulated with 40% corn grain + 20% soybean meal (T1), 40% corn grain + 17.5% soybean meal + 2.5% soybean curd (T2), 25% corn grain + 20% soybean meal + 15% green kernel rice (T3), and 30% corn grain + 15% soybean meal + 6% green kernel rice + 9% soybean curd (T4), respectively, with forage source of 10% alfalfa hay, 20% timothy hay, and 10% corn silage as fed-basis. In 24 and 48 hour cultivations, T4 showed significantly lower pH compared to T1, whereas in 3 and 24 hour cultivations, T4 showed significantly higher DM degradation compared to T1. In addition, the gas production of T3 was also higher than T1 (p<0.05). Overall results of the present experiments indicated that green kernel rice and soybean curd as agricultural by-products have the possibility of partial replacements of corn grain and soybean meal.