• Title/Summary/Keyword: Pretreatment method

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A feasibility study evaluating the relationship between dose and focal liver reaction in stereotactic ablative radiotherapy for liver cancer based on intensity change of Gd-EOB-DTPA-enhanced magnetic resonance images

  • Jung, Sang Hoon;Yu, Jeong Il;Park, Hee Chul;Lim, Do Hoon;Han, Youngyih
    • Radiation Oncology Journal
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    • v.34 no.1
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    • pp.64-75
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    • 2016
  • Purpose: In order to evaluate the relationship between the dose to the liver parenchyma and focal liver reaction (FLR) after stereotactic ablative body radiotherapy (SABR), we suggest a novel method using a three-dimensional dose distribution and change in signal intensity of gadoxetate disodium-gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) hepatobiliary phase images. Materials and Methods: In our method, change of the signal intensity between the pretreatment and follow-up hepatobiliary phase images of Gd-EOB-DTPA-enhanced MRI was calculated and then threshold dose (TD) for developing FLR was obtained from correlation of dose with the change of the signal intensity. For validation of the method, TDs for six patients, who had been treated for liver cancer with SABR with 45-60 Gy in 3 fractions, were calculated using the method, and we evaluated concordance between volume enclosed by isodose of TD by the method and volume identified as FLR by a physician. Results: The dose to normal liver was correlated with change in signal intensity between pretreatment and follow-up MRI with a median $R^2$ of 0.935 (range, 0.748 to 0.985). The median TD by the method was 23.5 Gy (range, 18.3 to 39.4 Gy). The median value of concordance was 84.5% (range, 44.7% to 95.9%). Conclusion: Our method is capable of providing a quantitative evaluation of the relationship between dose and intensity changes on follow-up MRI, as well as determining individual TD for developing FLR. We expect our method to provide better information about the individual relationship between dose and FLR in radiotherapy for liver cancer.

African American Race and Low Income Neighborhoods Decrease Cause Specific Survival of Endometrial Cancer: A SEER Analysis

  • Cheung, Min Rex
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.4
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    • pp.2567-2570
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    • 2013
  • Background: This study analyzed Surveillance, Epidemiology and End Results (SEER) data to assess if socio-economic factors (SEFs) impact on endometrial cancer survival. Materials and Methods: Endometrial cancer patients treated from 2004-2007 were included in this study. SEER cause specific survival (CSS) data were used as end points. The areas under the receiver operating characteristic (ROC) curve were computed for predictors. Time to event data were analyzed with Kaplan-Meier method. Univariate and multivariate analyses were used to identify independent risk factors. Results: This study included 64,710 patients. The mean follow up time (S.D.) was 28.2 (20.8) months. SEER staging (ROC area of 0.81) was the best pretreatment predictor of CSS. Histology, grade, race/ethnicity and county level family income were also significant pretreatment predictors. African American race and low income neighborhoods decreased the CSS by 20% and 3% respectively at 5 years. Conclusions: This study has found significant endometrial survival disparities due to SEFs. Future studies should focus on eliminating socio-economic barriers to good outcomes.

Anaerobic digestate as a nutrient medium for the growth of the green microalga Neochloris oleoabundans

  • Abu Hajar, Husam A.;Guy Riefler, R.;Stuart, Ben J.
    • Environmental Engineering Research
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    • v.21 no.3
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    • pp.265-275
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    • 2016
  • In this study, the microalga Neochloris oleoabundans was cultivated in a sustainable manner using diluted anaerobic digestate to produce biomass as a potential biofuel feedstock. Prior to microalgae cultivation, the anaerobic digestate was characterized and several pretreatment methods including hydrogen peroxide treatment, filtration, and supernatant extraction were investigated and their impact on the removal of suspended solids as well as other organic and inorganic matter was evaluated. It was found that the supernatant extraction was the most convenient pretreatment method and was used afterwards to prepare the nutrient media for microalgae cultivation. A bench-scale experiment was conducted using multiple dilutions of the supernatant and filtered anaerobic digestate in 16 mm round glass vials. The results indicated that the highest growth of the microalga N. oleoabundans was achieved with a total nitrogen concentration of 100 mg N/L in the 2.29% diluted supernatant in comparison to the filtered digestate and other dilutions.

Utilization of Osmotic Dehydration as Pretreatment prior to Drying (건조전처리로서 삼투건조의 이용)

  • 윤광섭
    • Food Science and Preservation
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    • v.5 no.3
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    • pp.305-314
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    • 1998
  • In the drying process, many undesirable physicochemical changes occur that influence dried food product qualities. Pretreatments method is used to reduce the deterioration of dried food product qualities such as color, flavor, texture, rehydration ability and retention of nutrients. The methods of pretreatments are blanching, chemical treatment and osmotic dehydration. Osmotic dehydration is a water removal process which is based on placing foods in a concentrated osmotic solution or in a dry osmotic material. A large number of process variables have a significant effect on process and final product quality. In order to improve final product quality it is necessary to know the role of each process variable and understand the mecanisms throughout the process. Osmotic dehydration is a valuable processing tool with great future in minimal processing of fruits and vegetables.

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Studies on the Enzymatic Hydrolysis of Lignocellulosic Materials for the Alternative Fuels (II) - The Effect of Delignification Treatment on the Enzymatic Hydrolysis of Steam - Exploded Woods - (대체연료(代替燃料) 생산(生産)을 위한 목질재료(木質材料)의 가수분해(加水分解)에 관한 연구(硏究)(II) - 탈(脫)리그닌처리가 폭쇄처리재(爆碎處理材)의 효소적(酵素的) 당화(糖化)에 미치는 영향(影響) -)

  • Cho, Nam-Seok
    • Journal of the Korean Wood Science and Technology
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    • v.18 no.4
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    • pp.18-25
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    • 1990
  • As polysaccharides in lignocellulosic materials are encrusted with aromatic lignin molecules and have high crystallinity, these require pretreatment to improve their digestability by cellulolytic enzymes. Though a number of pretreatment methods have been proposed, the steam explosion process is evaluated as a promising method. This study was performed to investigate the effect of delignification treatment by alkali, methanol and the others on the enzymatic hydrolysis. Delignification treatment resulted in great increase rate in enzymatic hydrolysis. Concerning to the effect of delignication reagents on the enzymatic hydrolysis, methanol treatment was more effective than alkali in the case of oak wood. In pine wood, the delignification did not showed any significant enhancement of hydrolysis rate. Complete delignification by Alkali-Oxygen. Alkali treatment showed high saccharification rate of 99.5%.

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Effects of $H_2$ Pretreatment using plasma for improved characteristics of Cu thin films (Cu 박막의 특성개선을 위한 플라즈마를 이용한 $H_2$ 전처리 효과)

  • 이종현;이정환;최시영
    • Journal of the Korean Vacuum Society
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    • v.8 no.3A
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    • pp.249-255
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    • 1999
  • Deposition characteristics of Cu thin films using Ar carrier gas and $H_2$ processing gas at various working pressures and substrate temperatures were investigated. Also, effects of $H_2$ pretreatment using plasma at $200^{\circ}C$ of substrate temperature and 0.6 Torr of chamber pressure were stdied. Cu thin films were deposited on TiN/Si substrate at working pressure of 0.5~1.5 Torr, substrate temperatures of 140~$240^{\circ}C$ with (hface)Cu(tmvs). Substrates were pretreated by $H_2$ plasma, and Cu films deposited in situ using twofold shower head. The purity, electrical resistivity, thickness, surface morphology, optical properties of the deposited Cu films were measured b the AES, four point probe, stylus profiler, SEM,. and the uv-visible spectrophotometer. This study suggests that $H_2$ plasma is an effective method for enhancing deposition rate and for producing high quality copper thin films.

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A Study on the Reduction of Inorganic Arsenic in Hijiki and Rice Using the Various Pretreatments and Inductively Coupled Plasma Mass Spectrometry

  • Nam, Sang-Ho;Lee, Dong-Chan
    • Mass Spectrometry Letters
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    • v.12 no.3
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    • pp.106-111
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    • 2021
  • Several pretreatment methods have been developed to reduce the inorganic arsenic, which is known to be highly harmful to humans, among various arsenic species present in hijiki and rice. The pretreatment methods were selected and developed as methods that can be non-harmful even after treatment and easily applied. Hijiki was applied by two methods. One was soaking in water at room temperature for various durations and the other was boiling of it in water for a short period of time. Rice was soaked in water with different rice-to-water ratios for various durations. The most effective method that reduced the inorganic arsenic in hijiki was to repeat parboiling for 5 minutes twice, which led to 79% reduction of the inorganic arsenic in it. In the case of rice, soaking for 24 hours at the ratio of 1:5 (rice:water) resulted in 51% reduction of inorganic arsenic in rice.

A Study on Carpospore Release Induction Method of Agarophyton vermiculophyllum (홍조류 꼬시래기(Agarophyton vermiculophyllum)의 과포자방출 유도 방법에 대한 연구)

  • Choi, Han Gil
    • Ocean and Polar Research
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    • v.42 no.3
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    • pp.225-231
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    • 2020
  • The aim of this study was to examine optimal induction method for carpospore release from Agarophyton vermiculophyllum cystocarps for seedling production. We tested the effects of environmental factors on carpospore release by using five different induction methods; spontaneous, desiccation, low temperature, desiccation+low temperature, and osmotic shock. Also, carpospores release was estimated at three temperatures (20, 25, and 30℃), and then under combinations of three day lengths (8, 12, and 16h) and two irradiances (30 and 60 μmol photons m-2 s-1), after pretreatment at desiccation+low temperature for 2 hr. The number of carpospores released was between 113 ~ 682 spores /cystocarp/day and it was maximal in the desiccation+low temperature treatment. Optimal environmental conditions for carpospore release of A. vermiculophyllum were 25℃, 16 h, and 60 μmol photons m-2 s-1. The present results suggest that massive carpospores for seedling production of A. vermiculophyllum could be obtained under a combination of 25℃, 16 h, and 60 μmol photons m-2 s-1 after pretreatment in the desiccation+low temperature.