• Title/Summary/Keyword: 투과계

Search Result 511, Processing Time 0.035 seconds

Embryo-Fetal Developmental Toxicity Study of Methoxycinnamidopropyl Polysilsesquioxane (Methoxycinnamidopropyl Polysilsesquioxane의 랫드를 이용한 배.태자 발생독성 연구)

  • Hong, Jeong-Sup;Lim, Jeong-Hyeon;Kim, Kang-Hyun;Park, Myeong-Kyu;Jo, Ki-Yeon;Park, Gil-Jong;Jung, Taek-Kyu;Kim, Ja-Young;Yoon, Kyung-Sup
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.37 no.3
    • /
    • pp.247-256
    • /
    • 2011
  • Existing organic UV protection materials seem to be problematic due to their penetration and irritation to skin. Inorganic UV protection materials are also at issue for safety of their nano-type transformation. Therefore, the recent studies of UV protection materials have been focused not only on the effectiveness but also on their safety. One of the UV protection materials in study which have higher safety is the organic-inorganic conjugation type UV protection material. Previously, we have reported the manufacturing process, physical property and UV protection efficiency of methoxychinnamidoprophy poloysilsesquixan as a new cross-linked polymer type UV protection material. In this study, we have evaluated the effect of the methoxychinnamidoprophy poloysilsesquixan on embryo-fetal development in SD rats. This study is expected to show some definite information related to the effect on pregnancy or embryo-fetal abnormality in case of the clinical exposure of the methoxychinnamidoprophy poloysilsesquixan.

Effects of the Rheological Properties of UV Cured Acrylic Pressure Sensitive Adhesive with Nano-particles on the Silk Screen Printing and Adhesion (실크 스크린 인쇄 및 점착력에 나노 입자가 포함된 UV 경화형 아크릴계 감압 점착제의 유변학적 특성)

  • Cho, Min-Jeong;Kang, Ho-Jong;Kim, Dong-Bok
    • Journal of Adhesion and Interface
    • /
    • v.18 no.1
    • /
    • pp.25-32
    • /
    • 2017
  • For application to display module junction process, the silk screen printing based on UV curable acrylic pressure sensitive adhesive(PSA) with silica nano-particles and the rheological properties were studied to investigate the effect on printability and adhesion. The monomers for PSA were based on 2-ethylhexyl acrylate(2-EHA) and acrylic acid(AA) 93:7, butyl acylate(BA), 2-hydroxyethyl acrylate(2-HEA) and tetrahydrofurfuryl acrylate(THFA) were added. Additionally, hydrophobic and hydrophilic nano-particles AEROSIL R974 and AEROSIL 200 were added, respectively. When the ratio of nano-particle was used above 4 or 7 phr, G' and ${\eta}^*$ were increased significantly. When the ratio of AEROSIL 200 was used above 7 phr, the penetration property was decreased during the silk screen printing. We found that the adhesion was decreased with increasing the nano-particle content, and it was decreased in the case of the hydrophilic nano-particle AEROSIL 200.

Induction of Spontaneous Neutrophil Apoptosis by 4-O-Methyl-Ascochlorin, A Prenyl Phenol Compound (프레닐 페놀계 항생제인 4-O-methyl-ascochlorin에 의한 호중구 세포사멸의 유도)

  • Son Dong-Aoon;Lee Sun-Young;Lee Min-Jung;Park Joo-In;Hong Young-Seob;Lee Yong-Hwan;Chang Young-Chae;Kwak Jong-Young
    • Journal of Life Science
    • /
    • v.16 no.1
    • /
    • pp.30-36
    • /
    • 2006
  • Neutrophils are short-lived leukocytes that play a vital role in immune responses to bacteria, yeast, and fungi. This study was performed to investigate the effect of 4-O-methyl-ascochlorin (MAC), an anti-tumor, antibiotic, and anti-fungal prenyl-phenol compound on the spontaneous apoptosis of human neutrophils. MAC time- and dose-dependently accelerated the spontaneous apoptosis of human neutrophils. The effect of MAC on neutrophil apoptosis was blocked by pre-treatment of the neutrophils with specific inhibitors of pancaspase (zVAD-fmk), caspase-8 (zIETD-fmk), or caspase-3 (zDEVD-fmk). The cleavage of procaspase-8 and procaspase-3 was increased by MAC. Mitochondrial permeability, which was measured by the retention of $DiOC_6(3)$, was dose-de-pendently increased by MAC but the change of mitochondrial permeability was not blocked by pretreatment of neutrophils with zIETD-fmk. These results suggest that MAC induces neutrophil apoptosis by caspase-8-dependent but mitochondria-independent manner.

The Localization of Lectin Receptors in the Tissue of the Paragonimus westermani (폐흡충조직내 Lectin(WGA) 수용체의 분포)

  • Kim, Soo-Jin;Nahm, Heun-Woo;Lee, Joon-Sang;Joo, Kyung-Whan
    • Applied Microscopy
    • /
    • v.30 no.1
    • /
    • pp.101-111
    • /
    • 2000
  • In this study, the distribution of lectin receptors in Paragonimus westermani tissue was explored using colloidal gold label complexed with lectin WGA purified from wheat germ (Triticum vulgare). The lectin WGA gold complex, shown to recognize GlcNAc (N-acetylgalactosamine) and NeuNAc (N-acetylneuraminic acid) regions, was applied to detect binding sites in Lowicryl HM 20 sections viewed under electron microscope. Labeled sections of the metacercaria revealed gold particles specifically distributed on the tegumental syncytium and lamella of the excretory canal. Labeling of young adult tissue was then quantified and compared to that of adult worm tissue. Adult worm tissue sections resulted in specific gold particle distribution on the lamella of caecal epithelium and excretory canal. These results indicate that lectin WGA receptors are located in the tegumental syncytium and lamella of the excretory canal of the metacercariae, and in the lamella of the caecum and excretory canal of the young adult and adult. Therefore, the GlcNAc and NeuNAc regions in the tegumental syncytium appear to be functionally associated with cell-recognition and protection from the immune system of the host, and linked with membrane transport and absorption of nutrients in the lamella of the excretaory canal and caecal epithelia.

  • PDF

Drug Delivery into the Blood-Brain Barrier by Endogenous Substances-A Role of Amine and Monocarboxylic Acid Carrier Systems for the Drug Transport- (내인성물질의 수송계를 이용한 혈액-뇌관문에의 약물송달V-약물의 혈액-뇌관문 투과성에 대한 염기성 아민 및 모노카르본산 수송계의 역할-)

  • Kang, Young-Sook
    • Journal of Pharmaceutical Investigation
    • /
    • v.20 no.4
    • /
    • pp.223-228
    • /
    • 1990
  • The contribution of endogenous transport systems to the blood-brain barrier (BBB) transport of basic and acidic drugs was studied by using a carotid injection technique in rats and an isolated bovine cerebrovascular disease state were compared between the normotensive rats (WKY) and stroke-prone spontaneously hypertensive rats (SHRSP) which have been well established as an animal model with pathogenic similarities to humans. Basic drugs such as eperisone, thiamine and scopolamine inhibited, in a concentration dependent manner the in vivo uptake of $[{^3}H]choline$ through BBB, whereas amino acids and acidic drugs such as salicylic acid and valproic acid did not inhibit the uptake. The uptake of $[^3H]choline$ by B-CAP increased with time and showed a remarkable temperature dependency. The uptake of $[^3H]choline$ by B-CAP showed the very similar inhibitory effects as observed in the in vivo brain uptake, and was competitively inhibited by a basic drug, eperisone. The in vivo BBB uptakes of $[^3H]acetic$ acid and $[^{14}C]salicylic$ acid were dependent on pH of the injectate and the concentration of drugs. Several acidic drugs such such as salicylic acid, benzoic acid and valproic acid inhibited the in vivo uptake of $[^3H]acetic$ acid, whereas amino acid, choline and a basic drug such as eperisone did not inhibit the uptake. The uptake of acetic acid by B-CAP was competitively inhibited by salicylic acid. The permeability surface area product (PS) through BBB for $[^3H]choline$ in SHRSP was significantly lower than that in WKY. The concentration of choline in the brain dialysate in SHRSP was about half of that in WKY, while no significant difference was observed in the plasma concentration of choline between SHRSP and WKY. No significant difference was observed in the transport of monocarboxylic acids, glucose and neutral amino acid through BBB between SHRSP and WKY. From these results, it was concluded that BBB transport system of choline contributes to the transport of basic drugs through BBB, that acidic drugs can be transported via a moncarboxylic acid BBB transport system and that the specific dysfuntion of the BBB choline transport in SHRSP was ascribed to the reduction of the maximum velocity of choline concentration in the brain interstitial fluids.

  • PDF

Determination of Thermal Radiation Emissivity and Absorptivity of Thermal Screens for Greenhouse (온실 스크린의 장파복사 방사율 및 흡수율 결정)

  • Rafiq, Adeel;Na, Wook Ho;Rasheed, Adnan;Kim, Hyeon Tae;Lee, Hyun Woo
    • Journal of Bio-Environment Control
    • /
    • v.28 no.4
    • /
    • pp.311-321
    • /
    • 2019
  • Greenhouse farmers often use thermal screens to reduce greenhouse heating expenses during the winter, and for shade during hot, sunny days in the summer, as it is an inexpensive solution to temperature control relative to other available options. However, accurate measurements of their emitted and absorbed radiations are important for the selection of suitable screens that offer maximum performance. Material's ability to save energy is highly dependent on these properties. Limited studies have investigated the measurement of these properties under natural conditions, but they are only applicable to materials having partial porosities. In this work, we describe a new radiation balance method for determining emissive power and absorptive capacity, as well as reflectivity, transmissivity and emissivity of materials having complete and partial transparency by using pyrgeometer and net radiometer. In this study, four materials with zero porosity, were tested. The emissivity value of PE, LD-13, LD-15 and PH-20 was $0.439{\pm}0.020$, $0.460{\pm}0.010$, $0.454{\pm}0.004$, and $0.499{\pm}0.006$, respectively. All tested samples showed high emitted radiation as compared to absorbed radiation.

A Study on the Decontamination of Cs-137 and Sr-90 Contained in the Liquid Radioactive Waste Discharged from the Spent Fuel Storage Tank Using Microalgae (미세조류를 이용한 사용후핵연료 저장조에서 배출되는 방사성 폐액에 함유된 Cs-137 및 Sr-90 제염에 관한 연구)

  • Kim, Tae Young;Park, Hye Min;Song, Yang Soo;Lee, Un Jang
    • Resources Recycling
    • /
    • v.31 no.5
    • /
    • pp.20-25
    • /
    • 2022
  • In this study, the applicability of microalgae was evaluated for eco-friendly decontamination of cesium-137 (Cs-137) and strontium-90 (Sr-90), which are radioactive nuclides contained in radioactive waste. The monolithic radioactive solution used in the experiment was manufactured at a concentration of 1.5 Bq/mL Cs-137 and 1.0 Bq/mL Sr-90 by diluting a standard radioactive solution and distilled water. This experiment used two types of microalgae, Chlorella Vulgaris was used for Sr-90 decontamination and Hematococcus pluvialis for Cs-137 decontamination. The experimental method is to put the microalgae cultured for 2 weeks into a bottle with a semi-permeable membrane, and then put the bottle in which the microalgae was put into the manufactured radioactive solution, so that the microalgae and the radioactive solution react through the semi-permeable membrane for 48 hours. For the radioactivity concentration analysis of each sample, a gamma-ray nuclide analyzer was used for Cs-137, a γ-ray isotope, and a Liquid Scintillation Count(LSC) was used f or Sr-90, a β-ray isotope. As a result of the experiment, it was confirmed that about 88.0 % of Cs-137 and about 89.7 % of Sr-90 could be decontaminated, and about 98.6 % of Sr-90 was finally able to be decontaminated by the two-stage decontamination method.

Feasibility Study of Isodose Structure Based Field-in-Field Technique for Total Body Irradiation (전신조사방사선치료 시 Isodose Structure를 이용한 Field-in-Field Technique의 유용성 평가)

  • Lee, Yoon Hee;Ban, Tae Joon;Lee, Woo Seok;Kang, Tae Young;Back, Geum Mun
    • The Journal of Korean Society for Radiation Therapy
    • /
    • v.25 no.1
    • /
    • pp.15-24
    • /
    • 2013
  • Purpose: In Asan Medical Center, Two parallel opposite beams are employed for total body irradiation. Patients are required to be in supine position where two arms are attached to mid axillary line. Normally, physical compensators are required to compensate the large dose difference for different parts of body due to the different thicknesses compared to the umbilicus separation. There was the maximum dose difference up to 30% in lung and chest wall compared to the prescription dose. In order to resolve the dose discrepancy occurring on different body regions, the feasibility of using Fieid-in-Field Technique is investigated in this study. Materials and Methods: CT scan was performed to The RANDO Phantom with fabricated two arms and sent to Eclipse treatment planning system (version 10.0, Varian, USA). Conventional plan with physical lead compensator and new plan using Field-in-Field Technique were established on TPS. AAA (Anisotropic Analytical Algorithm) dose calculation algorithm was employed for two parallel opposite beams attenuation. Results: The dose difference between two methods was compared with the prescription dose. The dose distribution of chest and anterior chest wall uncovered by patient arms was 114~124% for physical lead compensator while Field-in-Field Technique gave 106~107% of the dose distribution. In-vivo dosimetry result using TLD showed that the dose distribution to the same region was 110~117% for conventional physical compensator and 104~107% for Field-in-Field Technique. Conclusion: In this study, the feasibility of using FIF technique has been investigated with fabricated arms attached Rando phantom. The dose difference was up to 17% due to the attached arms. It is shown that the dose homogeneity is within ${\pm}10%$ with the CT based 3-dimensional 4 step FIF technique. The in-vivo dosimetry result using TLD was showed that 95~107% dose distribution compared to prescription dose. It is considered that CT based 3-dimensional Field-in-Field Technique for the total body irradiation gives much homogeneous dose distribution for different body parts than the conventional physical compensator method and might be useful to evaluate the dose on each part of patient body.

  • PDF

철도기준점을 이용한 철도중심선형 좌표변환에 관한연구 - 호남고속철도 계획노선을 중심으로 -

  • Moon, Cheung-Kyun;Heo, Joon;Kang, Sang-Du;Kim, Sang-Hoon
    • Proceedings of the KSR Conference
    • /
    • 2007.11a
    • /
    • pp.1141-1151
    • /
    • 2007
  • In this paper through Honam high-speed railroad which is planned with the north and south axis, we will verify the feasibility of the coordinate conversion using railroad control points after regarding current planned-railroad as the linear central axises. From analysis, distortion of Y axis varies 21cm to 40cm diminishing to a gentle straight line, distortion of X axis varies 14cm to 29cm. Through a revision, the deviation value between the coordinates were 6mm to 9mm and it satisfied the allowable error of national geographic information institute which is following ITRF (International Terrestrial Reference Frame) and cadastral boundary survey(10cm). consequently the coordinate conversion is possible using railroad control points as common control points.

  • PDF

Development of the Whole Body 3-Dimensional Topographic Radiotherapy System (3차원 전신 정위 방사선 치료 장치의 개발)

  • Jung, Won-Kyun;Lee, Byung-Yong;Choi, Eun-Kyung;Kim, Jong-Hoon;An, Seung-Do;Lee, Seok;Min, Chul-Ki;Park, Cham-Bok;Jang, Hye-Sook
    • Progress in Medical Physics
    • /
    • v.10 no.2
    • /
    • pp.63-71
    • /
    • 1999
  • For the purpose of utilization in 3-D conformal radiotherapy and whole body radiosurgery, the Whole Body 3-Dimensional Topographic Radiation Therapy System has been developed. Whole body frame was constructed in order to be installed on the couch. Radiopaque catheters were engraved on it for the dedicated coordinate system and a MeV-Green immobilizer was used for the patient setup by the help of side panels and plastic rods. By designing and constructing the whole body frame in this way, geometrical limitation to the gantry rotation in 3-D conformal radiotherapy could be minimized and problem which radiation transmission may be altered in particular incident angles was solved. By analyzing CT images containing information of patient setup with respect to the whole body frame, localization and coordination of the target is performed so that patient setup error may be eliminated between simulation and treatment. For the verification of setup, the change of patient positioning is detected and adjusted in order to minimize the setup error by means of comparison of the body outlines using 3 CCTV cameras. To enhance efficiency of treatment procedure, this work can be done in real time by watching the change of patient setup through the monitor. The method of image subtraction in IDL (Interactive Data Language) was used to visualize the change of patient setup. Rotating X-ray system was constructed for detecting target movement due to internal organ motion. Landmark screws were implanted either on the bones around target or inside target, and variation of target location with respect to markers may be visualized in order to minimize internal setup error through the anterior and the lateral image information taken from rotating X-ray system. For CT simulation, simulation software was developed using IDL on GUI(Graphic User Interface) basis for PC and includes functions of graphic handling, editing and data acquisition of images of internal organs as well as target for the preparation of treatment planning.

  • PDF