• Title/Summary/Keyword: Slow light

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Development on the abomasum of fetuses and neonates in Korean native goats (한국재래산양의 태아 및 신생아의 제4위 발달에 관하여)

  • Lee, Jong-hwan;Huh, Chan-kwen;Kim, Chong-sup;Kwak, Soo-dong
    • Korean Journal of Veterinary Research
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    • v.34 no.2
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    • pp.219-227
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    • 1994
  • The development of abomasum in fetuses between 60, 90, 120 days of gestation and neonates of Korean native goats was investigated by light, scanning and transmission electron microscopy. The results obtained were summarized as follows ; 1. The abomasum wall appeared to be differentiated into the epithelium, lamina propria, muscle layer, and serosa at 60 days of gestation. The epithelium was stratified columnar and these nuclei were located near the apical two thirds portion of the cell at 60 days of gestation, and then transformed into simple columnar epithelium with the flat basal nuclei. 2. The inner circular and outer longitudinal muscle layers were observed at 90 days of gestation and the blood vessels had become quite well developed as various arterioles, venules and capillaries of different size during this age. 3. Gastric pits were seen at 90 days of gestation and continued gradually to increase depth during gestation. 4. The mucous, parietal and chief cells appeared in epithelium at 90 days of gestation and continued gradually to increase in number during gestation. In 120 days fetuses and neonates, muscle layer had become very thickeness. 5. Scanning electron microscopically, the inner surface of the abomasum already consisted of wavy spiral folds which had many fine wrinkles at 60 days of gestation. In 90 day old fetuses, each spiral fold was enlarged and its surface was tended to be split into many straight longitudinal ridges and among these ridge were found shallow grooves, At 120 days, the subdivided swellings of ridges were progressively complicated in shape. In the neonates, the inner surface was flat and holed with many gastric pits. 6. Transmission electron microscopically, the epithelium was straified columnar and these nuclei were irregular shape at 60 days fetus. The parietal, chief and mucous cells were observed in 90 day old fetuses and continued gradually to increase in number during gestation. 7. The development of the abomasum was relatively slow at early stages, it was accelerated greatly in the last of gestation.

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Use of Near Infrared Spectroscopy in the Meat Industry

  • Akselsen, Thorvald M.
    • Proceedings of the Korean Society for Food Science of Animal Resources Conference
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    • 2000.11a
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    • pp.1-14
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    • 2000
  • The Near Infrared region of the energy spectrum was first discovered by Hershel in the year 1800. The principles of NIR is based on light absorption of specific organic chemical bonds. The absorption at each wavelength is measured and a spectre is obtained. The spectre is then treated mathematically and with the absorption data is converted to absolute units via a calibration. In the last two decades it has developed dramatically. With the invention of computers and the ability to treat a large amount of data in a very short time the use of NIR for many different purposes has developed very fast. During the last decade with the aid of very powerful PC's the application of NIR technology has become even more widespread. Now or days development of very robust calibrations can be done in a relatively short time with a minimum of resources. The use of Near Infrared Spectroscopy (NIR) in the Meat industry is relatively new. The first installations were taken into operation in the 80ties. The Meat Industry in often referred to as rather conservative and slow to embrace new technologies, they stay with the old and proven methods. The first NIR instruments used by the Meat Industry, and most other industries, were multipurpose build, which means that the sample presentation was not well suited to this particular application, or many other applications for that sake. As the Meat Industry grows and develops to meet the demands of the modern markets, they realise the need for better control of processes and final products. From the early 90 ties and onward the demand for 'rear time' rapid results starts growing, and some suppliers of NIR instruments (and instruments based on other technologies, like X-ray) start to develop and manufacture instrumentation dedicated to the particular needs of the Meat Industry. Today it is estimated that there are approximately 2000 rapid instruments placed in the Meat industry world-wide. By far most of these are used as at-line or laboratory installations, but the trend and need is moving towards real on-line or in-line solutions. NIR is the most cost effective and reproducible analytical procedure available for the twenty first century.

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Preparation and Characterization of Cisplatin-Incorporated Chitosan Hydrogels, Microparticles, and Nanoparticles

  • Cha, Ju-Eun;Lee, Won-Bum;Park, Chong-Rae;Cho, Yong-Woo;Ahn, Cheol-Hee;Kwon, Ick-Chan
    • Macromolecular Research
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    • v.14 no.5
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    • pp.573-578
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    • 2006
  • Three different, polymer-platinum conjugates (hydrogels, microparticles, and nanoparticles) were synthesized by complexation of cis-dichlorodiammineplatinum(II) (cisplatin) with partially succinylated glycol chitbsan (PSGC). Succinic anhydride was used as a linker to introduce cisplatin to glycol chitosan (GC). Succinylation of GC was investigated systematically as a function of the molar ratio of succinic anhydride to glucosamine, the methanol content in the reaction media, and the reaction temperature. By controlling the reaction conditions, water-soluble, partially water-soluble, and hydrogel-forming PSGCs were synthesized, and then conjugated with cisplatin. The complexation of cisplatin with water-soluble PSGC via a ligand exchange reaction of platinum from chloride to the carboxylates induced the formation of nano-sized aggregates in aqueous media. The hydrodynamic diameters of PSGC/cisplatin complex nano-aggregates, as determined by light scattering, were 180-300 nm and the critical aggregation concentrations (CACs), as determined by a fluorescence technique using pyrene as a probe, were $20-30{\mu}g/mL$. The conjugation of cisplatin with partially water-soluble PSGC, i.e., borderline between water-soluble and water-insoluble PSGC, produced micro-sized particles $<500{\mu}m$. Cisplatin-complexed PSGC hydrogels were prepared from water-insoluble PSGCs. All of the cisplatin-incorporated, polymer matrices released platinum in a sustained manner without any significant initial burst, suggesting that they may all be useful as slow release systems for cisplatin. The release rate of platinum increased with the morphology changes from hydrogel through microparticle to nanoparticle systems.

A Study on the Dyeing of Silk Fabrics Treated with Aplysia kurodai Extract (군소 추출색소를 이용한 견직물의 염색성에 관한 연구)

  • Kim, Hyun-Mi;Kim, Sang-Bum;Jang, Ae-Ran
    • Korean Journal of Human Ecology
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    • v.21 no.4
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    • pp.791-803
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    • 2012
  • This study intends to identify applicability of natural dye extracted from Aplysia kurodai, aiming to standardization of Aplysia kurodai natural dyeing through scientific validation by analyzing characteristics of pigment elements to review dyeability, colorfastness and antibacterial activity. Such material as silk fabrics that is animal fiber were used for this purpose, and derived following summarized results. UV/VIS spectrum analysis on the pigment of Aplysia kurodai that was extracted from purple gland showed that maximum absorbtion was near 540 nm. The silk fabric optimal dyeing can be achieved at a temperature of $55^{\circ}C$ with a colorant concentration of 5%. Dyed at $55^{\circ}C$ with interval of 10~90 minutes for identifying dye uptake over time to observed slow increase of dye uptake over time, and equilibrium occurred at 50 minutes. For dye uptake according to pH, while dye uptake was superior in acidity, it decreased rapidly in a base after pH 7. For color changes according to pH variation, it was reddish purple in acidity and was purplish red in a base. For color changes according to mordanting method, more clear color change had been obtained when process with aluminium pre-mordanting than non-mordanting and post-mordanting. The colorfastness to light, perspiration and washing was 1, 4~5, and 3~4 ratings respectively. The silk fabric dyed with Aplysia kurodai demonstrated excellent antimicrobial activity to Staphylococcus aureus and Klebsiella pneumoniae. The Aplysia kurodai can be used as a new colorant for the natural dyeing of silk.

Cardiorespiratory Responses of Qi-training: A Pilot Study

  • Lee, Myeong-Soo;Kim, Soo-Keun;Kim, Hye-Jung;Moon, Sun-Rock
    • Advances in Traditional Medicine
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    • v.4 no.1
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    • pp.18-21
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    • 2004
  • Six volunteers (mean $age=25.7{\pm}1.7$, $height=173{\pm}1.9$ and $weight=63.4{\pm}2.3{\;}kg$) participated in a graded exercise test and one hour of basic form of ChunDoSunBup (CDSB) Qi-training to investigate the cardiorespiratory responses and exercise intensity of Qi-training, a Korean traditional psychosomatic training. In the maximal exercise, the trainee showed $96.2{\pm}8.89{\;}l/min$ in ventilation (VE), $46.0{\pm}4.4$ in breath frequency (BF), $1.31{\pm}0.05$ in respiratory exchange ratio (RER), $180.7{\pm}3.0$ in heart rate (HR), and $2.6{\pm}1.1{\;}l/min$ or $40.7{\pm}2.3{\;}ml/kg/ml$ in oxygen consumption $(VO_2)$. Qi-training induced significant changes in BF, RER, HR, and $VO_2$. The exercise intensity of Qi-training were 42.3%, 46.9% and 38.7% of $HR_{max}$ during the sound exercise, slow motion (haeng-gong) and meditation respectively and the average was 46.2% of $HR_{max}$. We conclude that Qi-training is an aerobic exercise of a light (mild) intensity exercise, and it leads to decrease the metabolic rate in the trainee by breathing efficiently and relaxing them. In addition, Qi-training may affect cardiorespiratory function of BF, RER, HR and $VO_{2max}$ in trainees.

Performance Evaluation and Analysis of NVM Storage for Ultra-Light Internet of Things (초경량 사물인터넷을 위한 비휘발성램 스토리지 성능평가 및 분석)

  • Lee, Eunji;Yoo, Seunghoon;Bahn, Hyokyung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.6
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    • pp.181-186
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    • 2015
  • With the rapid growth of semiconductor technologies, small-sized devices with powerful computing abilities are becoming a reality. As this environment has a limit on power supply, NVM storage that has a high density and low power consumption is preferred to HDD or SSD. However, legacy software layers optimized for HDDs should be revisited. Specifically, as storage performance approaches DRAM performance, existing I/O mechanisms and software configurations should be reassessed. This paper explores the challenges and implications of using NVM storage with a broad range of experiments. We measure the performance of a system with NVM storage emulated by DRAM with proper timing parameters and compare it with that of HDD storage environments under various configurations. Our experimental results show that even with storage as fast as DRAM, the performance gain is not large for read operations as current I/O mechanisms do a good job hiding the slow performance of HDD. To assess the potential benefit of fast storage media, we change various I/O configurations and perform experiments to quantify the effects of existing I/O mechanisms such as buffer caching, read-ahead, synchronous I/O, direct I/O, block I/O, and byte-addressable I/O on systems with NVM storage.

AN ELECTRON MICROSCOPIC STUDIES OF RADIATION EFFECTS ON THE ENAMEL DEVELOPMENT OF THE RAT MOLAR (방사선조사가 백서구치법랑질발육에 미치는 영향에 관한 전자현미경적 연구)

  • Cho Hyo-Suck;You Dong-Soo
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.25 no.2
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    • pp.483-499
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    • 1995
  • Mandibular first molars of the rats were undertaken to observe the radiosensitivity of amelogenesis. Twenty four Sprague-Dawley rats received 396cGy radiation with the MK Cell irradiator using Cs-137, and twenty four rats served as control. They were devided into two groups; Group 1 which received radiation at the 14th day after gestation and group 2 which received radiation at the 19th day after gestation. Light Microscopy and Transmitted Electron Microscopy investigation was undertaken in the group 1 at the 15th, 18th, 20th, 22nd(2 days after birth), and 25th day(5 days after birth) after gestation, and in the group 2 at the 21th(birth day), 22nd(2 days after birth), and 25th(5 days after birth) day after gestation. The following histopathologic findings were obtained. 1. Compared with control group, experimental group showed a delayed formation of enamel and dentin due to slow rate of differentiation of undifferentiated mesenchymal cells. 2. In the experimental groups, the arrangement of the inner enamel epithelium was irregular and there were many vacuoles in the cytoplasm. There were dilated rER and mitochondria, increase of the intercellular space, and loss of the cellular polarity. 3. In the group 1, early enamel without Tomes' process, and early organic matrix was observed at the 25th day after gestation. 4. In the group 2, histopathologic changes were similar to those of the group 1, but the degree of changes was more severe than that of the group 1.

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A Case of Epithelioid Hemangioendothelioma Involving the Lung and Liver (폐와 간을 침범한 유상피 세포성 혈관내피종 1예)

  • Lee, Seung-Keun;Choi, Seung-Hyuk;Yang, Dong-Gyoo;Park, Jae-Min;Kim, Seong-Kyoo;Lee, Won-Young;Shin, Dong-Hwan
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.6
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    • pp.1396-1402
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    • 1997
  • Epithelioid Hemangioendothelioma(EH) is a rare vascular tumor, originating from endothelial cells. The principal locations are lung, soft tissue, bone and liver. This tumor is of borderline malignancy, relatively benign course. In the lung, the tumor is often multifocal, bilateral and frequently lead to the mistaken diagnosis of metastatic carcinoma. Although EH of the lung is relatively slow growing tumor, extensive pulmonary involvement, systemic metastasis, mainly to the liver have been documented. A 26-year-old man with EH involving the lung and liver was reported. Chest X-ray and chest CT showed multiple nodules in both lung fields and Abdominal CT multiple round low densities in liver. Transbronchial lung biopsy was performed. The patient diagnosed as EH by light microscopic finding and immunohistochemical study for Factor VIII-related antigen.

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Effect of citrate coated silver nanoparticles on biofilm degradation in drinking water PVC pipelines

  • Nookala, Supraja;Tollamadugu, Naga Venkata Krishna Vara Prasad;Thimmavajjula, Giridhara Krishna;Ernest, David
    • Advances in nano research
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    • v.3 no.2
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    • pp.97-109
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    • 2015
  • Citrate ion is a commonly used reductant in metal colloid synthesis, undergoes strong surface interaction with silver nanocrystallites. The slow crystal growth observed as a result of the interaction between the silver surface and the citrate ion makes this reduction process unique compared to other chemical and radiolytic synthetic methods. The antimicrobial effects of silver (Ag) ion or salts are well known, but the effects of citrate coated Ag nanoparticles (CAgNPs) are scant. Herein, we have isolated biofilm causative bacteria and fungi from drinking water PVC pipe lines. Stable CAgNPs were prepared and the formation of CAgNPs was confirmed by UV-visible spectroscopic analysis and recorded the localized surface plasmon resonance of CAgNPs at 430 nm. Fourier transform infrared spectroscopic analysis revealed C=O and O-H bending vibrations due to organic capping of silver responsible for the reduction and stabilization of the CAgNPs. X-ray diffraction micrograph indicated the face centered cubic structure of the formed CAgNPs, and morphological studies including size (average size 50 nm) were carried out using transmission electron microscopy. The hydrodynamic diameter (60.7 nm) and zeta potential (-27.6 mV) were measured using the dynamic light scattering technique. The antimicrobial activity of CAgNPs was evaluated (in vitro) against the isolated fungi, Gram-negative and Gram-positive bacteria using disc diffusion method and results revealed that CAgNPs with 170ppm concentration are having significant antimicrobial effects against an array of microbes tested.

Garbage Collection Method for NAND Flash Memory based on Analysis of Page Ratio (페이지 비율 분석 기반의 NAND 플래시 메모리를 위한 가비지 컬렉션 기법)

  • Lee, Seung-Hwan;Ok, Dong-Seok;Yoon, Chang-Bae;Lee, Tae-Hoon;Chung, Ki-Dong
    • Journal of KIISE:Computing Practices and Letters
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    • v.15 no.9
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    • pp.617-625
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    • 2009
  • NAND flash memory is widely used in embedded systems because of many attractive features, such as small size, light weight, low power consumption and fast access speed. However, it requires garbage collection, which includes erase operations. Erase operation is very slow. Besides, the number of the erase operations allowed to be carried out for each block is limited. The proposed garbage collection method focuses on minimizing the total number of erase operations, the deviation value of each block and the garbage collection time. NAND flash memory consists of pages of three types, such as valid pages, invalid pages and free pages. In order to achieve above goals, we use a page rate to decide when to do garbage collection and to select the target victim block. Additionally, We implement allocating method and group management method. Simulation results show that the proposed policy performs better than Greedy or CAT with the maximum rate at 82% of reduction in the deviation value of erase operation and 75% reduction in garbage collection time.