• Title/Summary/Keyword: Grinding Center

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Occlusal rehabilitation of post-traumatic malocclusion patient after reduction of panfacial fracture, using selective occlusal adjustment and implant prostheses on centric relation: a case report (다발성 안면 골절의 정복 후 발생한 부정교합 상태의 환자를 중심위에서 선택적 교합 조정 및 임플란트 보철수복으로 교합관계를 회복시킨 증례)

  • Dae-Kyun Kim;So-Young Park;Jung-Jin Lee;Yeon-Hee Park;Kyoung-A Kim;Jae-Min Seo
    • Journal of Dental Rehabilitation and Applied Science
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    • v.39 no.4
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    • pp.204-213
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    • 2023
  • Invasive or non-invasive reduction of fractures could be conducted as treatments of traumatic maxillofacial bone fractures. But when suboptimal reduction or malunion of maxillofacial bone fracture occurs, malocclusion could occur as a result of the lost relationship of the mandible and midface. This malocclusion is called post-traumatic malocclusion and orthognathic surgery, orthodontic treatment, selective grinding and prosthetic reconstruction are suggested as treatments for post-traumatic malocclusion after securement of stable TMJ. Stable TMJ is essential for occlusal rehabilitation to prevent occlusal change and relapse of malocclusion. Centric relation and adapted centric posture are suggested as start points of occlusal rehabilitation because they are most stable TMJ position. This case report presents a case in which post-traumatic malocclusion occurred after reduction of panfacial fracture. To rehabilitate full mouth occlusion, selective grinding and prosthetic reconstruction of implant supported fixed prostheses were conducted in centric relation and showed satisfying results in functional and occlusal aspects.

Investigation of the Optimum Operational Condition of Bio-Hydrogen Production from Waste Activated Sludge (폐활성 슬러지로부터 생물학적 수소 생산을 위한 최적 조건 연구)

  • Kim, Dong-Kun;Lee, Yun-Jie;Yu, Myong-Jin;Pak, Dae-Won;Kim, Mi-Sun;Sang, Byoung-In
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.4
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    • pp.362-367
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    • 2006
  • Waste activated sludge(WAS) collected from domestic wastewater treatment plant is biomass that contains large quantities of organic matter. However, relevant literature show that the bio-hydrogen yield using WAS was too low. In this study, the effect of pretreatment of WAS on hydrogen yield was investigated. Pretreatment includes acid and alkali treatments, grinding, heating, ozone and ultrasound methods. After pretreatment organic matters of WAS were solubilized and soluble chemical oxygen demand(SCOD) was increased by 14.6 times. Batch experiments were conducted to investigate the effects of pre-treatment methods and buffer solution, hydrogen partial pressure, and sodium ion on hydrogen production from WAS by using heated anaerobic mixed cultures. Experimental results showed that addition of buffer solution, efficient pre-treatment method with alkali solution, and gas sparging condition markedly increased the hydrogen yield to 0.52 mmol $H_2/g$-DS.

Beneficial Effects of Nano-sized Bee Pollen on Testosterone-induced Benign Prostatic Hyperplasia in Rodents (테스토스테론-유도 양성전립선비대증에서 나노화 벌 화분의 효능 연구)

  • Bak, Jia;Pyeon, Hae-In;So, Soojeong;Lee, Seunghyun;Lee, Seungmin;Suh, Hwa-Jin;Kang, Jae Seon;Choi, Yun-Sik;Chung, Il Kyung
    • Journal of Life Science
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    • v.28 no.4
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    • pp.465-471
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    • 2018
  • Bee pollen is one of many types of alternative remedies, and it has been used for a long time throughout the world. It has numerous health effects, including antifungal, antibacterial, and antioxidant properties, immune modulation, enhanced cell proliferation, and even anti-carcinogenic effects. This study was designed to elucidate the effects of bee pollen on benign prostatic hyperplasia in rodents. For this experiment, we used nano-sized bee pollen produced through wet-grinding technology, thereby the extraction efficiency of the active ingredients in the bee pollen was significantly enhanced. First, We found that nano-sized bee pollen significantly reduced the size of prostates enlarged by chronic testosterone administration. In addition, nano-sized bee pollen significantly reduced the plasma concentration of the prostate-specific antigen (PSA). Interestingly, nano-sized bee pollen did not reduce the testosterone-induced increase in the plasma concentration of prostaglandin $E_2$ ($PGE_2$). The beneficial effects of nano-sized bee pollen in reducing both the size of the prostate and the plasma concentration of PSA was comparable to that of dutasteride. Finally, nano-sized bee pollen did not cause damage in LNCaP cells which are androgen-sensitive human prostate adenocarcinoma cells. Together, these data indicate that nano-sized bee pollen may be able to be used as a good alternative remedy for the treatment of benign prostatic hyperplasia.

Evaluation of Exposure Indicators for Plants by Silicon Tetrachloride Release (사염화규소 누출사고지점 주변 식물에 대한 노출지표 평가)

  • Park, Jae-Seon;Kim, Jee-Young;Kim, Myeong-Ock;Park, Hyun-Woo;Chung, Hyen-Mi;Choi, Jong-Woo
    • Korean Journal of Environmental Agriculture
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    • v.36 no.4
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    • pp.288-292
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    • 2017
  • BACKGROUND: Silicon tetrachloride reacts with moisture in the atmosphere to generate hydrogen chloride, which affects the environment. Since silicon tetrachloride and its by-products are dispersed in the atmosphere in a short time after the silicon tetrachloride release into the atmosphere, it is difficult to directly assess the extent of environmental impact. In the present study, the exposure test of silicon tetrachloride or hydrogen chloride was examined in order to establish the criterion of the range affected by the silicon tetrachloride release, and the actual crops in the area exposed to silicon tetrachloride leakage were analyzed. METHODS AND RESULTS: For the experiment of exposure to silicon tetrachloride or hydrogen chloride, the leaves of red-pepper and corn were used in glass sealed containers. In the actual accident area, 59 samples from 10 different kinds of crops were collected. The pretreatment of the sample was performed by freezing and grinding, and then extracted using distilled water. The pH and concentration of chloride ($Cl^-$) ion of the extracted solution were measured using pH meter and ion chromatograph, respectively. CONCLUSION: Exposure to silicon tetrachloride caused visible damage, increasing the concentration of chloride ion, and decreasing the pH as well as hydrochloric acid. In the actual crops of the affected area, the tendency was the same as the result of the laboratory test, and the range of influence could be estimated through the concentration of $Cl^-$ ion over 2,000 mg/kg, and the correlation evaluation between the concentration of $Cl^-$ and pH. Therefore, the concentration of $Cl^-$ ion and the correlation between $Cl^-$ and pH would be considered as the factors to estimate the influence range of silicon tetrachloride release.

Removal of mid-frequency error from the off-axis mirror

  • Kim, Sanghyuk;Pak, Soojong;Jeong, Byeongjoon;Shin, Sangkyo;Kim, Geon Hee;Lee, Gil Jae;Chang, Seunghyuk;Yoo, Song Min;Lee, Kwang Jo;Lee, Hyuckee
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.103-103
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    • 2014
  • Manufacturing of lens and mirror using Diamond Turning Machine (DTM) offers distinct advantages including short fabrication time and low cost as compared to grinding or polishing process. However, the DTM process can leave mid-frequency error in the optical surface which generates an undesirable diffraction effect and stray light. The mid-frequency error is expected to be eliminated by mechanical polishing after the DTM process, but polishing of soft surface of ductile aluminum is extremely difficult because the polishing process inevitably degrades the surface form accuracy. In order to increase its surface hardness, we performed electroless nickel plating on the surface of diamond-turned aluminum (Al-6061T6) off-axis mirrors, which was followed by the 6-hour-long baking process at $200^{\circ}C$ for improving its hardness. Then we polished the nickel plated off-axis mirrors to remove the mid-frequency error and measured polished mirror surfaces using the optical surface profilometer (NT 2000, Wyko Inc.). Finally, we ascertained that the mid-frequency error on the mirror surface was successfully removed. During the whole processes of nickel plating and polishing, we monitored the form accuracy using the ultra-high accurate 3-D profilometer (UA3P, Panasonic Corp.) to maintain it within the allowable tolerance range (< tens of nm). The polished off-axis mirror was optically tested using a visible laser source and a pinhole, and the airy pattern obtained from the polished mirror was compared with the unpolished case to check the influence of mid-frequency error on optical images.

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Anti-Gout Effect of Ethanol Extracts from Chrysanthemum indicum Linne (감국(Chrysanthemum indicum Linne) 에탄올 추출물의 통풍억제 효과)

  • Park, So-Young;Cho, Young-Je
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.6
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    • pp.797-804
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    • 2016
  • In an acute toxicity test for Chrysanthemum indicum Linne, 0.5~10 g/kg of Chrysanthemum indicum Linne extracts were administered. Chrysanthemum indicum Linne did not produce acute toxicity even at high doses of 10 g/kg, making it a highly safe material. In the chronic toxicity test, oral administration of Chrysanthemum indicum Linne up to 2 g/kg was carried out for 13 weeks, showing liver non-toxicity. The gout inhibitory effect of Chrysanthemum indicum Linne extracts was measured by inflammatory cytokine expression and foot thickness after 24 h of monosodium urate crystal (MSU) oral administration when inflammatory cytokine production reached a maximum. The group administered 2~4 g/kg of Chrysanthemum indicum Linne extract showed an inhibitory effect on gout inflammation and edema, whereas the 10 g/kg administered group showed an increase in inflammation. Therefore, the moderate concentration of Chrysanthemum indicum Linne extract for gout inhibitory effect was under 4 g/kg. Chrysanthemum indicum Linne extract showed an anti-inflammatory effect on MSU as a relatively safe material at high capacity. These results indicate that Chrysanthemum indicum Linne extract is thought to be an excellent substance for gout prevention.

A Study on the Removal of Minor Elements from Aluminum Hydroxide with Organic Acids (유기산(有機酸)을 이용(利用)한 Aluminum Hydroxide의 미량원소(微量元素) 제거연구(除去硏究))

  • Lee, Hwa-Young;Cho, Sung-Baek
    • Resources Recycling
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    • v.17 no.5
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    • pp.44-51
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    • 2008
  • The removal of minor elements such as Na, Ca and Fe has been performed from domestic aluminum hydroxide of 99.7% purity with organic acids. Oxalic and citric acid were used as the leaching agent, respectively and aluminum hydroxides of different particle size were also employed for the purification with organic acid leaching. Fine grinding of aluminum hydroxide has been tested using ball mills and leaching characteristics of each element have also been examined in terms of leaching parameters such as temperature, acid concentration, and solid density. As a result, it was found that oxalic acid showed higher leaching efficiency than citric acid in the concentration range of 0.1 to 1.0 mole/l and leaching amount of each element was also increased with the acid concentration and reaction temperature. It was observed that about 45% of Na was leached out during ball milling process which implied that the majority of Na contained in aluminum hydroxide was water soluble compound.

Studies on the Near Infrared Diffuse Reflection Spectroscopy for Meat Components (근적외선 반사분광분석법에 의한 정육 및 그 구성성분의 반사 spectra에 관한 연구)

  • Oh, Eun-Kyong;Grossklaus, Dieter
    • Korean Journal of Food Science and Technology
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    • v.24 no.5
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    • pp.404-407
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    • 1992
  • This study was conducted to determine the effect of the physical and chemical factors on the absorbance when the chemical component of food was rapidly and effectively analyzed with near infrared reflection spectrophotometer. The absorbance was measured within the wavelength range of 1100 and 2500m and at the various sample temperatures. The absorbance was greatly increased with the rising sample temperature. When the grinding time of samples prolonged, the absorbance was decreased. The absorption peaks occurring in the near infrared spectra of meat, meat protein, pork fat and water were attributed to the overtone and combination vibration of C-H, N-H, O-H or C=O bond within the macromolecules of each sample. The absorbance was lower for meat protein than other meat components. Pork fat was characterized by the ${\cdot}CH_2{\cdot}$ absorption peak at the wavelength of 1700 and 2300 nm and water by the relatively high absorption peak at the wavelength of 1450 and 1930 nm. As a result, the absorbance of near infrared reflection spectrum of meat was affected mainly by fat and water in meat.

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Improved Methodology for Identification of Cryptomonads: Combining Light Microscopy and PCR Amplification

  • Xia, Shuang;Cheng, Yingyin;Zhu, Huan;Liu, Guoxiang;Hu, Zhengyu
    • Journal of Microbiology and Biotechnology
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    • v.23 no.3
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    • pp.289-296
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    • 2013
  • Cryptomonads are unicellular, biflagellate algae. Generally, cryptomonad cells cannot be preserved well because of their fragile nature, and an improved methodology should be developed to identify cryptomonads from natural habitats. In this study, we tried using several cytological fixatives, including glutaraldehyde, formaldehyde, and their combinations to preserve field samples collected from various waters, and the currently used fixative, Lugol's solution was tested for comparison. Results showed that among the fixatives tested, glutaraldehyde preserved the samples best, and the optimal concentration of glutaraldehyde was 2%. The cell morphology was well preserved by glutaraldehyde. Cells kept their original color, volume, and shape, and important taxonomic features such as furrow/gullet complex, ejectosomes, as well as flagella could be observed clearly, whereas these organelles frequently disappeared in Lugol's solution preserved samples. The osmotic adjustments and buffers tested could not preserve cell density significantly higher. Statistical calculation showed the cell density in the samples preserved by 2% glutaraldehyde remained stable after 43 days of the fixation procedure. In addition, DNA was extracted from glutaraldehyde preserved samples by grinding with liquid nitrogen and the 18S rDNA sequence was amplified by PCR. The sequence was virtually identical to the reference sequence, and phylogenetic analyses showed very close relationship between it and sequences from the same organism. To sum up, the present study demonstrated that 2% unbuffered glutaraldehyde, without osmotic adjustments, can preserve cryptomonads cells for identification, in terms of both light microscopy and phylogenetic analyses based on DNA sequences.

The effect of smoking on the quality boiled sausage (훈제 처리가 가열소지에 미치는 영향)

  • 정청송;유상훈
    • Journal of Applied Tourism Food and Beverage Management and Research
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    • v.12 no.2
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    • pp.1-41
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    • 2001
  • The effect of smoking on the quality sausage Sausages were prepared from beef, port, chickens, games, fish and shellfish with polyphosphate salt and spices. Sausage history goes back to 3,000 years of age. The procedure of sausage 1) Meat Curing 2) Meat Control 3) Add Spices 4) Permissible Ingredients 5) Grinding 6) Mixing Emulsion 7) Stuffing 8) Showing 9) Smoking 10) Cooking 11) Drying 12) Packaging Sausage Product to get information on the effect of smoking onto the quality of meat produces. Sausage was smoked under a given conditions. Smoking was conducted as 35f$^{\circ}C$to 6$0^{\circ}C$ the related humidity of smokehouse was still at 60 to 70 percent. Results are as follows: 1. The Penetrated smoke in sausage was prolonged < p.<0.02 when sausage was smoked 2hours at 60~$65^{\circ}C$ the penetrated amount of free acetone in sausage was 0.5mg%. 2. Peroxide value of sausage as heating treatment both at 3$0^{\circ}C$ and at 5$0^{\circ}C$ was prolonged. 3. When sausage was heated at 3$0^{\circ}C$, bacteria of sausage increased In number while at 60~$65^{\circ}C$ bacteria of sausage increased In number fourteen hours. 4. When sausage was treated with smoking the distribution of free amino acids in sausage was changed markedly. 5. The longer smoking time of the products was the higher the content. 6. In case of oak wood smoke flavoring all of test samples. 7. Rapid decrease of does-response mutagenic curve of the smoke flavoring of oak wood and apple wood by in the peak of curve and phenol in the smoke flavoring. Continuous efforts are required to make sausages easily in the butcher shops and in the restaurants. 8. Sausage texture evaluation has 13 rules. It is Elasticity, Surface Moisture, Surface Smoothness, Center Hardness, Skin Toughness, Cohesiveness, Denseness, Moisture Release, Cohesiveness of Mass, Lumpiness, Graininess (of Contents), Skin separation, Oiliness and sensory 11 rules evaluation is color, texture, mold, flavor, sweet test, salty, sourness, bitter, and savory taste. 9. Smoked, component, peroxide value, bacteria, color, free amino acid, tenderness, flavor, shrinkage are important values.

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