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Comparative Analysis of Treatment Planning System and Dose Distribution of Gamma knife PerfexionTM using EBT-3 Film (EBT-3 필름을 사용한 감마나이프 퍼펙션TM의 치료 계획 시스템 및 선량 분포 비교 분석)

  • Jin, Seongjin;Kim, eongjin;Seo, Weonseop;Hur, Beongik
    • Journal of the Korean Society of Radiology
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    • v.11 no.6
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    • pp.509-515
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    • 2017
  • The purpose of this study is to measure the 3 dimensional dose distribution of Gamma knife $Perfection^{TM}$, make a comparative analysis of the result and establish the measurement method for the procedures using EBT3 film. The dose distributions of the Gamma knife $Perfection^{TM}$ installed in two hospitals were evaluated in accuracy and precision. For accuracy, the difference between the mechanical center axis and the dose center axis was assessed on a 4 mm collimator. The allowed difference in accuracy is within 0.3 mm and it was measured as 0.098 mm, 0.195 mm for A hospital and 0.229 mm, and 0.223 mm for B hospital. For precision the difference between the FWHM(Full Width at Half Maximum) of Gamma Plan and measurement in the 4, 8, and 16 mm collimators was calculated. The allowed difference in precision is less than ${\pm}1mm$. The value of the hospital A was -0.283 ~ 0.583 mm, and the hospital B was -0.857 ~ 0.810 mm. When analyzing the dose distributions using the image-j program, it is necessary to establish a clearer reference point of the measurement point, and it is considered that the comparison of the dose distribution should be performed in actual treatment irradiation dose with a high dose usable film.

Improving Microalgal Biomass Productivity and Preventing Biofouling in Floating Marine Photobioreactors via Sulfonation of Selectively Permeable Membranes (부유형 해양 광생물반응기의 선택적 투과막의 술폰화 반응을 통한 Biofouling 억제 및 미세조류 생산성 향상)

  • Kim, Kwangmin;Lee, Yunwoo;Kim, Z-Hun;Park, Hanwool;Jung, Injae;Park, Jaehoon;Lim, Sang-Min;Lee, Choul-Gyun
    • Journal of Marine Bioscience and Biotechnology
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    • v.9 no.1
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    • pp.14-21
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    • 2017
  • The purpose of this study was to inhibit biofouling on a selectively permeable membrane (SPM) and increase biomass productivity in marine photobioreactors (PBRs) for microalgal cultivation by chemical treatment. Surfaces of a SPM, composed of polyethylene terephthalate (PET), was sulfonated to decrease hydrophobicity through attaching negatively charged sulfonic groups. Reaction time of sulfonation was varied from 0 min to 60 min. As the reaction time increased, the water contact angle value of SPM surface was decreased from $75.5^{\circ}$ to $44.5^{\circ}$, indicating decrease of surface hydrophobicity. Furthermore, the water permeability of sulfonated SPM was increased from $5.42mL/m^2/s$ to $10.58mL/m^2/s$, which reflects higher nutrients transfer rates through the membranes, due to decreased hydrophobicity. When cultivating Tetraselmis sp. using 100-mL floating PBRs with sulfonated SPMs, biomass productivity was improved by 34% compared with the control group (non-reacted SPMs). In addition, scanning electron microscopic observation of SPMs used for cultivation clearly revealed lower degree of cell attachment on the sulfonated SPMs. These results suggest that sulfornation of a PET SPM could improve microalgal biomass productivity by increasing nutrients transfer rates and inhibiting biofouling by algal cells.

Model Simulation for Assessment of Image Acquisition Errors Affecting Electron Tomography (영상 자료 획득시의 오류가 전자토모그래피 결과에 미치는 영향 고찰-모델 시뮬레이션을 중심으로)

  • Jou, Hyeong-Tae ;Lee, Su-Jeong;Kim, Youn-Joong;Suk, Bong-Chool
    • Applied Microscopy
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    • v.38 no.1
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    • pp.51-61
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    • 2008
  • This simulation study examined the effect of data acquisition error including the data type of TEM image, and incident beam intensity of the tilt series on 3D tomograms. Simulation was performed with the 3D head phantom model of Kak and Slaney, and the slightly modified 3D head phantom model with enhanced difference in absorption coefficients. Reconstructed tomogram for the original head phantom model using 8-bit gray-scale image was distorted with extremely high level of noise, while an acceptable result was obtained for the modified model. The results for the original model using wrong formulation for the transmitted beam intensity was proved to be incorrect. The high level of noise along the z direction was found in case of the modified model. On the other hand, the wrong value of incident beam intensity in both models gave distorted results. In order to reconstruct an artifacts-free 3D structure from the projections with invisible features in electron tomography, the 16-bit projection images should be used with the correct incident beam intensity which is applied to Beer's law.

Environmental effects in the stellar populations of Compact Elliptical galaxies

  • Kim, Suk;Jeong, Hyunjin;Lee, Youngdae;Joo, Seok-Joo;Lee, Jaehyun;Sung, Eon-Chang
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.1
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    • pp.30.2-31
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    • 2017
  • Compact elliptical (cE) galaxies are in a rare class of stellar systems characterized by high stellar densities, small sizes, high velocity dispersion, and high metallicity corresponding to elliptical galaxies. cE galaxies have been observed around massive galaxies, so they could be formed under strong influences of tidal stripping and truncation. However, the recent discovery of isolated cE galaxies requires the need of new formation scenarios. We aim at finding cE galaxies in various environments using SDSS DR12, and studying stellar population of cEs as function of environments. Based on the typical properties of cE galaxies, we selected cE candidates by restricting that low-luminosity Mg > 19.5 mag, small sizes Re < 700 pc, and high velocity dispersions ${\sigma}$ > $60kms^{-1}$. Since effect radii of cE candidates are mostly smaller than the seeing size of SDSS photometry, we calculated the effective radius by fitting a Sersic profile. In addition, we assumed that host galaxies have brightness with Mr < -21 mag, and an environmental parameter is computed as distances between cE galaxies and host-galaxies. We found 112 cE galaxies at z < 0.05, which have high sersic indices (mean value is 5.2) similar to the typical massive elliptical galaxies. Mgb values of cE galaxies increase as the distances from the host galaxies decrease. Especially, for cEs close to the host galaxies (NcE; $D_{host}$ < 300 pc), the Mgb values are similar to those of massive elliptical galaxies, which is consistent with the previous studies. On the other hand, cE galaxies distant from the host galaxies (DcE; Dhost >300 pc) have lower Mgb values than the conventional cE. The Mgb values follow the ${\sigma}$-Mgb relation of elliptical galaxies, and are connected to its faint end. This can be explained as a result of different merger histories for differing environments. For example, NcE galaxies are formed by tidal stripping by massive galaxies as suggested by previous studies, but DcE galaxies could be linked with high-redshift spheroids (e.g. red nuggets) which have not evolved into present-day elliptical galaxies because of the environmental influences.

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Effects of Bedding Material Composition in Deep Litter Systems on Bedding Characteristics and Growth Performance of Limousin Calves

  • Meng, J.;Shi, F.H.;Meng, Qingxiang;Ren, L.P.;Zhou, Z.M.;Wu, H.;Zhao, L.P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.1
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    • pp.143-150
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    • 2015
  • The objective of this study was to evaluate the effects of different litter mixture compositions on bedding system temperature, pH and volatile fatty acid and ammonia-N ($NH_3$-N) content, and the serum physico-chemical parameters and growth indices of calves. Thirty-two Limousin calves ($280{\pm}20kg$) were randomly assigned to four groups (n = 8 for each group) according to the bedding system used: i) control with soil only (CTR); ii) mixture with 50% paddy hulls (PH), 30% saw dusts (SD), 10% peat moss (PM) and 10% corn cobs (CC) (TRT1); iii) mixture with 15% PH, 15% SD, 10% PM, 40% CC, and 20% corn stover (CS) (TRT2); iv) mixture with 30% PH, 10% PM, 40% CC, and 20% CS (TRT3). The litter material combinations of different treatments were based on the cost of bedding system materials in China. The cost of four treatments from low to high: Control$NH_3$-N level (271.83 to 894.72 mg/kg) was lowest for TRT1 (p<0.0001) and highest for TRT2 (p<0.0001). The acetate, propionate and butyrate levels were highest for the control group (p<0.0001). In all the groups, the pH value (6.90 to 9.09) increased at the beginning and later remained stable at below 9.09. The temperature of deep litter increased at the first week and reached the maximum ($42.1^{\circ}C$) on day 38. 3,5,3'-Triiodothyronine ($T_3$) levels in the TRT1 group animals (p<0.0001) were lower than those in the control and TRT2 animals. 3,5,3',5'-Tetraiodothyronine ($T_4$) in the TRT1 group (p = 0.006) was lower than that in the other treatment groups. Cortisol (COR) in the control and TRT1 group was lower (p<0.0001) than that in the TRT2 and TRT3 groups. Corticosterone (CORt) in the control group was higher (p<0.0001) than that in the treatment groups. The findings indicate that the deep litter bedding systems provided better conditions for animal health and growth performance compared with the control system. Furthermore, the litter composition of TRT1 was found to be optimal among the three treatment groups.

Nutritive Evaluation of Poultry Waste and Sudex Grass Silage for Sheep

  • Chaudhry, S.M.;Naseer, Z.;Alkraidees, M.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.10 no.1
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    • pp.79-85
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    • 1997
  • Cage layer waste and sudex grass were ensiled in the proportions of 0:100, 30:70, 40:60 and 50:50 wet basis, respectively. The influence of ensiling cage layer waste on Salmonellae, Shigella, Proteus, and total number of colony forming units (CFU) was investigated. The nutritive value of the silages was evaluated in a digestion trial. The experiment was conducted with 24 wethers allotted to four silages. Initial samples of cage layer waste showed $0.11{\times}10^6$ CFU and salmonellae, Shigella and Proteus were present. Ensiling was effective in complete elimination of all the pathogens. Dry matter, crude protein and ash contents were increased linearly (p < .01) with the increase of cage layer waste in the silages ($358g{\cdot}kg^{-1}$ to $484g{\cdot}kg^{-1}$; $76.3g{\cdot}kg^{-1}$ to $183.2g{\cdot}kg^{-1}$ and $38.5g{\cdot}kg^{-1}$ to $169.4g{\cdot}kg^{-1}$; DM basis, respectively). Water solubles carbohydrate values for silages were 38.3, 22.5, 20.1 and $20.0g{\cdot}kg^{-1}$ DM basis, respectively. Ensiling decreased the pH values for all the silages and the decrease was higher for sudex grass ensiled alone than grass ensiled with cage layer waste. Lactic acid concentration in silages increased linearly (p < .01) with the increase of cage layer waste. The apparent digestibilities of DM, OM and CP for the animals fed sudex grass silage alone were 496.0, 516.1, $496.7g{\cdot}kg^{-1}$ DM basis respectively. However, digestibilities of all the components were higher (p < 0.01) for the animals fed silages containing cage layer waste. Among waste containing diets, the digestibilities of all the components showed quadratic affect (p < 0.01), increased for silages containing 30 and 40% cage layer waste and decreased when the level of waste increased from 40 to 50%. The results indicated that cage layer waste can be used upto 40% in ruminant diet as a source of N without any adverse effect on the health of animals. Ensiling appeared to be feasible and effective method for eliminating the pathogen present in cage layer waste.

Prostate Cancer Epidemiology in a Rural Area of North Western Greece

  • Grivas, N.;Hastazeris, K.;Kafarakis, V.;Tsimaris, I.;Xousianitis, Z.;Makatsori, A.;Raptis, P.;Aspiotis, S.;Ioachim, E.;Ntemou, A.;Kitsiou, E.;Malamou-Mitsi, V.;Sofikitis, N.;Kordela, V.;Papandreou, C.;Agnantis, N.J.;Stavropoulos, N.E.
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.3
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    • pp.999-1002
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    • 2012
  • Epirus is a rural area of North-Western Greece. We reviewed data from 4 hospitals for 4.975 patients who underwent prostate biopsy in Epirus in the twelve year period from 1999 to 2010. Two six -year periods were compared (1999-2004 and 2004-2010). All cases of prostate cancer confirmed by biopsy were recorded and age-standardized incidence rates per 100,000 males were calculated. We also recorded the clinical stage for patients diagnosed in our hospital and correlated this with PSA and Gleason scores. Percentage of positive prostate biopsies was also calculated. There were a total of 1714 new cases during 1999-2010 and the mean annual age-adjusted incidence was 34/100.000. The mean incidences during 1999-2004 and 2005-2010 were 26/100,000 and 42/100,000, respectively. The mean age at diagnosis was 74. The most common Gleason score was 6 and the prevalent clinical stage was T2. Median PSA at diagnosis was 10.8 ng/ml. There was a significant difference between stage cT4 and all other stages regarding PSA value (p=0.000). A positive correlation was found between Gleason score and PSA (p=0.013). These results are in accordance with the incidence rise recorded in neighboring countries of South-East Europe. However we should keep in mind the risk of overdiagnosis and the detection of low-risk cancers that would not have caused morbidity or death during a man's lifetime anyway.

Chemical Composition, In situ Digestion Kinetics and Feeding Value of Oat Grass (Avena sativa) Ensiled with Molasses for Nili-Ravi Buffaloes

  • Khan, Muhammad Ajmal;Sarwar, M.;Nisa, M.;Iqbal, Z.;Khan, M.S.;Lee, W.S.;Lee, H.J.;Kim, H.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.8
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    • pp.1127-1133
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    • 2006
  • This study examined the effect of cane molasses and fermentation time on chemical composition and characteristics of oat grass silage (OGS) and its in situ digestion kinetics, intake, digestibility, milk yield and composition in buffaloes (Bubalus bubalis). Oat grass (OG) harvested at 50-days of age was ensiled in laboratory silos with cane molasses at the rate of 0, 2, 4 and 6% of OG dry matter (DM) for 30, 35 and 40 days. Silage pH was decreased while lactic acid content increased with increasing level of cane molasses and fermentation time. Dry matter (DM), crude protein (CP) and true protein (TP) content of OGS were (p<0.05) significantly higher with higher cane molasses levels. However, they were not affected by the fermentation time. Similar trends were observed for neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose, acid detergent lignin and ash content of OGS. The OG ensiled for 30-days with 2% molasses was screened from laboratory study and used to determine comparative in situ DM and NDF digestion kinetics of OG and its silage. In situ DM and NDF digestibilities of OG were significantly (p<0.05) higher than OGS. Ruminal DM and NDF lag time, rate and extent of digestion of OG and its silage were similar. Two experimental diets of OG and OGS were formulated using 75:25 forage to concentrate ratio on a DM basis. Dry matter and CP intakes were similar in lactating buffaloes fed either OG- or OGS-based diets. However, NDF intake was higher in buffaloes fed the OG-compared with OGS-based diet. Apparent DM, CP and NDF digestibilities were similar in lactating buffaloes fed either OG- or OGS-based diets. Milk yield (4% FCM) was similar in buffaloes fed either OG-(10.3 kg/d) or OGS-(9.95 kg/d) based diets. Milk fat, total solids and true protein content were higher with OG compared with the OGS diet. Solids not fat and CP content were similar in milk of buffalo fed either OG or OGS. The results of this study indicate that OG ensiled with 2% molasses could safely replace 75% DM of green oat fodder in the diets of lactating buffaloes without negatively affecting intake, digestibility, milk yield and composition.

Effects of Supplementation of Mulberry (Morus alba) Foliage and Urea-rice Bran as Fermentable Energy and Protein Sources in Sheep Fed Urea-treated Rice Straw Based Diet

  • Yulistiani, Dwi;Jelan, Z.A.;Liang, J.B.;Yaakub, H.;Abdullah, N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.4
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    • pp.494-501
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    • 2015
  • A digestibility study was conducted to evaluate the effects of supplementing mulberry foliage and urea rice-bran as a source of fermentable energy and protein to 12 sheep fed diets based on urea-treated rice straw (TRS). The three dietary treatments were: T1, TRS with mulberry; T2, TRS with 50% mulberry replaced with rice bran and urea; and T3, TRS with rice bran and urea. The study was arranged in a completely randomized design with four replications for each treatment. The sheep were fed one of the three diets and the supplements were offered at 1.2% of the body weight (BW) and the TRS was provided ad libitum. There were no differences (p>0.05) among the three treatment groups with respect to dry matter (DM) intake ($76.8{\pm}4.2g/kg\;BW^{0.75}$) and DM, organic matter (OM), and crude protein (CP) digestibility ($55.3{\pm}1.22$; $69.9{\pm}0.85$; $46.3{\pm}1.65%$ respectively for DM, OM, and CP). The digestibility of fiber (neutral detergent fiber [NDF] and acid detergent fiber) was significantly lower (p<0.05) for T3 (46.2 and 46.6 respectively) compared to T1 (55.8 and 53.7 respectively) and T2 (54.1 and 52.8 respectively). Nitrogen (N) intake by sheep on diet T3 was significantly (p<0.05) higher than sheep fed diet T1. However, N balance did not differ among the three diets ($3.0{\pm}0.32g/d$). In contrast, the rumen ammonia ($NH_3-N$) concentrations in sheep fed T2 and T3 were significantly (p<0.05) higher than in sheep fed T1. The $NH_3-N$ concentrations for all three diets were above the critical value required for optimum rumen microbial growth and synthesis. Total volatile fatty acid concentrations were highest (p<0.05) in T1 (120.3 mM), whilst the molar proportion of propionic acid was highest in T3 (36.9%). However, the microbial N supply in sheep fed T1 and T3 was similar but was significantly (p<0.05) higher than for sheep fed T2. It was concluded that mulberry foliage is a potential supplement of fermentable energy and protein for sheep fed TRS based diet. The suggested level of supplementation is 1.2% of BW or 32% of the total diet since it resulted in similar effects on the intake of DM, OM, and NDF, digestibility of DM, OM, and CP, N utilization and microbial supply when compared to rice bran and urea supplementation.

Replacing Concentrate with Wheat Straw Treated with Urea Molasses and Ensiled with Manure: Effects on Ruminal Characteristics, In situ Digestion Kinetics and Nitrogen Metabolism of Nili-Ravi Buffalo Bulls

  • Hassan, Z.;Nisa, M.;Shahzad, M.A.;Sarwar, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.8
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    • pp.1092-1099
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    • 2011
  • To evaluate the effects of replacing concentrate with urea molasses treated fermented wheat straw (FWS) ensiled with cattle manure (CM) on ruminal characteristics, in situ digestion kinetics and nitrogen (N) metabolism was studied in Nili Ravi cannulated buffalo bulls in a $4{\times}4$ Latin Square Design. Wheat straw treated with urea (4%) and molasses (6%) was ensiled with cattle manure (CM) (70:30) and fermented for 40 days. Four iso-nitrogenous and iso-caloric diets were formulated. In the FWS0, FWS10, FWS20 and FWS30 diets 0, 10, 20 and 30% of the concentrate was replaced with FWS, respectively. Daily intake by bulls was restricted to 1.5% dry matter (DM) of body weight. Ruminal ammonia nitrogen concentration was greater (p<0.05) in bulls fed FWS diet than for those fed FWS0 diet at 3, 6, 9 and 12 h post-parandial. Bulls fed FWS 20 and FWS 30 diets had higher ruminal pH at 3 and 6 h post-parandial than bulls fed FWS10 and FWS0. Ruminal total volatile fatty acid (VFA) concentrations 3 h post-parandial were greater (p<0.05) in bulls fed FWS0 than those fed FWS diets. However ruminal VFA tended to increase at 6, 9 and 12 h post-parandial as the level of FWS increased. In situ ruminal DM and neutral detergent fiber (NDF) degradation, rates of disappearance and extent of digestion were higher (p<0.05) for bulls fed FWS30 diet than those fed FWS0. Ruminal DM and NDF lag time tended to decrease (p<0.05) as FWS concentration in the diet increased. Feed intake, nitrogen intake, N-balance and blood urea-N did not differ (p>0.05) in buffalo bulls fed different diets. Wheat straw treated with urea and molasses and ensiled with CM enhanced the nutritive value of wheat straw and improved nutrient utilization in buffalo bulls when up to 30% of the concentrate was replaced with FWS; no adverse effects on ruminal characteristics and nutrients digestibilities were detected.