• Title/Summary/Keyword: Removal mechanism

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TREATMENT OF OKC ON RAMUS OF MANDIBLE BY SAGITTAL SPLITTING TECHNIQUE (하악 상행지부에 발생한 치성각화낭의 시상 분할 골절단술을 이용한 치험례)

  • Song, Hyun-Woo;Ryu, Dong-Mok;Kim, Yeo-Gab;Lee, Baek-Soo;Kwon, Young-Dae;Choi, Byung-Jun;Kim, Young-Ran;Yim, Jin-Hyuk;Lee, Jung-Gyo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.31 no.5
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    • pp.408-413
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    • 2009
  • Odontogenic keratocyst (OKC) is a epithelial developmental cyst which were first described by Phillipsen in 1956. The frequency of OKC has been reported to vary from 3% to 11% of odontogenic cysts. The most characteristic clinical aspect of OKC is the high frequency of recurrence. The mechanism of recurrence is thought to be related to residues of cyst epithelium and an intrinsic growth potential following excision. And since the lining of the OKC is thin and friable, removal of the cyst in one piece may sometimes be difficult. Complete removal of the cyst lining without leaving behind remnants attached to the soft tissue or bone is necessary to avoid recurrence. Therapeutic approaches vary in different studies from marsupialization and enucleation, which may be combined with adjuvant therapy such as cryotherapy or Carnoy's solution, to marginal or radical resection. The recurrent rate varies from approximately 20% to 62%. And OKC in the angle-ramus region of the mandible had a higher tendency to recur, because of the difficulty in accessing and removing OKC from the ramus. By employing a sagittal splitting of the mandible a good surgical access was provided and cyst could be removed completely. We present an illustrative case of a small, lobulated OKC that involved ramus on mandible, and a review of the contemporary literature.

Research on Design Capacity Evaluation of Low Impact Development according to Design Criteria (저영향개발 시설 설계 기준에 따른 용량 평가 방법 연구)

  • Im, Jiyeol;Gil, Kyungik
    • Journal of Wetlands Research
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    • v.24 no.1
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    • pp.59-67
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    • 2022
  • The interest in LID facilities is increasing worldwide for recovery of natural water cycle system to destroy by urbanization. However, problems are raised when installation of LID because comprehensive analysis about design capacity adequacy of LID facilities was not conducted completely. In this research, removal efficiency and design volume adequacy of LID facilities were analyzed based on rainfall monitoring data in four LID facilities(Vegetated Swale, Vegetative Filter Strip, Bio-Retention and Permeable Pavement). As a result, group of LID facility designed on WQV was shown higher flow(37%) and pollutants(TSS, BOD, TN and TP) removal efficiencies(20 ~ 37%) than group of LID facility designed on WQF. SA/CA graph was drawn for evaluation of design volume adequacy based on rainfall monitoring data. In this SA/CA graph, coefficient of determination show over 0.5 in all parameter, especially, Flow and TP were show over 0.95. And, 'SA/CA & L/CA' graph considering difference of structure mechanism in LID facility suggested in this research was confirmed that improved coefficient of determination in flow, TSS and TP than SA/CA graph. According to this research results, feasibility of applying 'SA/CA & L/CA' graph for evaluation of design volume adequacy in LID facility, and it is necessary to follow up research for generalization and normalization.

Ultrasonic Immersion-steam Cleaning and High Temperature Drying Process for Removing Cutting Oil on Titanium Turning Scraps (타이타늄 터닝 스크랩 내 절삭유 제거를 위한 초음파 침지-스팀 및 고온 건조 공정)

  • Chae, Jikwang;Yoo, Suhwan;Oh, Jung-Min;Lim, Jae-Won
    • Resources Recycling
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    • v.30 no.1
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    • pp.60-65
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    • 2021
  • The recycling of titanium turning scraps requires the removal of cutting oil and other contaminants remaining on the surface. In this study, an experiment was conducted in which titanium scraps were cleaned by a combination of ultrasonic immersion-steam cleaning and subsequent drying at high temperature. To determine the removal mechanism of cutting oil, the contact angle between titanium surface and cutting oil was measured. The result confirmed the optimum condition of the immersion solution of the titanium turning scraps. In the case of immersion cleaning of Na4P2O7 aqueous solution, the degree of carbon removed in the cutting oil was the highest at 50℃, and it was confirmed that the carbon content obtained from the combination of steam cleaning and ultrasonic immersion-steam cleaning was lower than that from steam cleaning after ultrasonic immersion. The oxidation and decomposition behaviors of cutting oil were investigated using Thermogravimetric analysis (TGA) and the result was applied in the high temperature drying process. From the results of the high temperature drying tests, it was concluded that 200℃ is the optimal drying temperature.

Efficient Poisoning Attack Defense Techniques Based on Data Augmentation (데이터 증강 기반의 효율적인 포이즈닝 공격 방어 기법)

  • So-Eun Jeon;Ji-Won Ock;Min-Jeong Kim;Sa-Ra Hong;Sae-Rom Park;Il-Gu Lee
    • Convergence Security Journal
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    • v.22 no.3
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    • pp.25-32
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    • 2022
  • Recently, the image processing industry has been activated as deep learning-based technology is introduced in the image recognition and detection field. With the development of deep learning technology, learning model vulnerabilities for adversarial attacks continue to be reported. However, studies on countermeasures against poisoning attacks that inject malicious data during learning are insufficient. The conventional countermeasure against poisoning attacks has a limitation in that it is necessary to perform a separate detection and removal operation by examining the training data each time. Therefore, in this paper, we propose a technique for reducing the attack success rate by applying modifications to the training data and inference data without a separate detection and removal process for the poison data. The One-shot kill poison attack, a clean label poison attack proposed in previous studies, was used as an attack model. The attack performance was confirmed by dividing it into a general attacker and an intelligent attacker according to the attacker's attack strategy. According to the experimental results, when the proposed defense mechanism is applied, the attack success rate can be reduced by up to 65% compared to the conventional method.

Research on the Production of CO2 Absorbent Using Railway Tie Concrete Waste (콘크리트 철도 침목 폐기물을 활용한 CO2 포집제 제조 연구)

  • Gyubin Lee;Jae-Young Lee;Hyung-Jun Jang;Sangwon Ko;Hye-Jin Hong
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.11 no.3
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    • pp.260-266
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    • 2023
  • In recent years, excessive emissions of carbon dioxide(CO2) have become the cause of global climate change. Consequently, there has been significant research activity aimed at both removing and utilizing CO2. This study assesses the potential utilization of railway tie concrete waste, generated from railway infrastructure, as a CO2 absorption material and investigates the physicochemical properties before and after CO2 absorption to understand the CO2 removal mechanisms. Railway tie concrete waste primarily consists of Si(26.60 %) and contains 9.82 % of Ca. Compared to samples of Cement and Normal concrete waste, it demonstrated superior potential for use as a CO2 absorption material, with approximately 98 % of the Ca content participating in CO2 absorption reactions. Through Thermogravimetric Analysis(TGA) and X-ray Diffraction(XRD) analysis, it was confirmed that the carbonate reaction, where the Ca in railway tie concrete waste converts into CaCO3 through reaction with CO2 gas, is the primary mechanism for CO2 removal. Furthermore, Scanning Electron Microscopy(SEM) analysis revealed the formation of numerous CaCO3 particles with sizes less than 0.1 ㎛ after the CO2 absorption reaction. This transformation of large internal voids in the CO2 absorption material into mesopores resulted in an increase in the specific surface area of the material.

Effect of Sunghyangchungisan on Contractile Reactivity and $Ca^{2+}$ metabolism in Isolated Rabbit Carotid Artery (성향정기산(星香正氣散)이 가토의 경동맥(頸動脈) 평활근(平滑筋) 긴장(緊張) 및 $Ca^{2+}$ 대사(代謝)에 미치는 영향(影響))

  • Kim, Young-Gyun;Kweon, Jung-Nam;Kim, Jong-Hoon
    • The Journal of Internal Korean Medicine
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    • v.21 no.3
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    • pp.377-388
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    • 2000
  • Objective : This study was undertaken to evaluate the effect of Sunghyangchungisan (SHCS) on the regulation of vascular tone and $Ca^{2+}$ metabolism in arterial tissues. Vascular rings isolated from rabbit carotid artery were myographed isometrically in isolated organ baths and the effect of SHCS on contractile activities, endothelial function and $Ca^{2+}$ metabolism were determined. Methods : In phentobarbital sodium-anesthetized rabbits, SHCS administered through ear vein (100 mg/Kg body wt.) or intragastric dwelling tube (300 mg/Kg body wt.) attenuated phenylephrine (PE, 10 ${\mu}g$/Kg, i.v.)-induced increases in both systolic and diastolic cartoid arterial blood pressure. Results : In experiments with isolated arterial strips, SHCS relaxed arterial rings which were pre-contracted by phenylephrine (PE, 1 ${\mu}M$). The responses to SHCS were partially dose-dependent at concentrations lower than 0.5 mg/ml. When SHCS was applied prior to the exposure to PE, it inhibited the PE-induced contraction by a similar magnitude which was comparable to the relaxation of pre-contracted arterial rings. Washout of SHCS after observing its relaxant effect resulted in a full recovery of PE-induced contractions, indicating that the action mechanism is reversible. The observation that SHCS did not change the $ED_{50)$ of PE oh its dose-response curve ruled out the possible interaction of SHCS with ${\alpha}$-receptors. The relaxant effect of SHCS was not affected by removal of endothelium or a nitric oxide synthase inhibitor, L-NAME. Methylene blue, an inhibitor of the soluble guanylate cyclase, did not affect the relaxant effect of SHCS. These results suggest that the action of SHCS is not mediated by the endothelium nor soluble guanylate cyclase. Constant cGMP production determined in arterial strips in the presence or absence of SHCS is consistent with this conclusion. When contraction was induced by additive application of $Ca^{2+}$ in arterial rings which were pre-depolarized by high $K^+$ in a $Ca^{2+}$-free solution, the relaxant effect of SHCS was attenuated by increasing the $Ca^{2+}$ concentration. SHCS, when applied to the arterial rings pre-contracted by PE and then relaxed by nifedipine, a $Ca^{2+}$ channel blocker, did not show additive relaxation. SHCS partially blocked $Ca^{2+}$ influx stimulated by PE and high $K^+$ which was determined by 5-min ^{45}Ca$ uptake, while it did not affect $Ca^{2+}$ efflux. Conclusions : From above results, it is suggested that SHCS relax PE-induced contraction of rabbit carotid artery in an endothelium independent manner, andinhibition of $Ca^{2+}$ influx may contribute to the underling mechanism.

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Mechanism of Relaxation of Rat Aorta by Scopoletin; an Active Constituent of Artemisia Capillaris

  • Kwon Eui Kwang;Jin Sang Sik;oChoi Min H;Hwang Kyung Taek;Shim Jin Chan;Hwang Il Taek;Han Jong Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.2
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    • pp.389-396
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    • 2002
  • In the present work, we examined the mechanism of vasorelaxant effect of scopoletin, an active constituent of Artemisia capillaris on rat thoracic descending aortic rings. Scopoletin induced a concentration-dependent relaxation in rat thoracic descending aortic rings pre-contracted with phenylephrine (EC/sub 50/ = 238.94±37.4 μM), while it was less effective in rat thoracic descending aortic rings precontracted with high potassium solution (KCI 30 mM). Vasorelaxation by scopoletin was significantly inhibited after endothelial removal, but recovered at high concentration. Pretreatment of rat thoracic descending aortic rings with N/sup G/-nitro-L-arginine (100 μM), a nitric oxide synthase inhibitor, and atropine (1 μM), a muscarinic receptor antagonist, significantly inhibited scopoletin-induced relaxation of rat thoracic descending aortic rings. Neither indomethacin (3 μM), an inhibitor of cydooxygenase, nor propranolol (1 μM), a β -adrenoceptor antagonist, modified the effect of scopoletin. The combination of N/sup G/ -nitro-L-arginine (100 μ M) and miconazole (10 μ M), an inhibitor of cytochrome P 450, did not modify the effect of scopoletin, when compared with pretreatment with N/sup G/-nitro-L-arginine(100 μM) alone. Vasorelaxant effect of scopoletin was inverted by pretreatment with diltiazem (10 μM), a Ca/sup 2+/-channel blocker, at low concentration, while restored at high concentration. Apamin (K/sub ca/-channel blocker, 1 μM), 4-aminopyridine (4-AP, K/sub v/-channel blocker, 1 mM), and tetrodotoxin (TTX, Na/sup +/-channel blocker 1 μM) potentiated the vasorelaxant effect of scopoledn, but glibendamide (K/sub ATP/-channel blocker, 10 μM), tetraetylammonium(TEA, non-selective K-channel blocker, 10 mM) did not affect the relaxation of scopoletin. Free radical scavengers (TEMPO, catalase, mannitol) did not modify vascular tone. These results suggest that nitric oxide, Ca/sup 2+/ -channels play a role in endothelium-dependent relaxations to scopoletin in rat aortas, that apamin, 4-AP, TTX but not glibenclamide, TEA potentiated relaxation to scopoletin mediated by these channels, and that free radicals do not concern to the vasorelaxant effect of scopoletin.

Sodium Salicylate Activates p38MAPK Though a Specific-Sensing Mechanism, Distinct from Pathways Used by Oxidative Stress, Heat Shock, and Hyperosmotic Stress

  • Kim, Jung-Mo;Oh, Su-Young;Kim, Min-Young;Seo, Myoung-Suk;Kang, Chi-Duk;Park, Hye-Gyeong;Kang, Ho-Sung
    • Biomedical Science Letters
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    • v.9 no.4
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    • pp.241-248
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    • 2003
  • Sodium salicylate, a plant stress hormone that plays an important role(s) in defenses against pathogenic microbial and herbivore attack, has been shown to induce a variety of cell responses such as anti-inflammation, cell cycle arrest and apoptosis in animal cells. p38MAPK plays a critical role(s) in the cell regulation by sodium salicylate. However, the signal pathway for sodium salicylate-induced p38MAPK activation is yet unclear. In this study, we show that although sodium salicylate enhances reactive oxygen species (ROS) production, N-acetyl-L-cysteine, a general ROS scavenger, did not prevent sodium salicylate-induced p38MAPK, indicating ROS-independent activation of p38MAPK by sodium salicylate. Sodium salicylate-activated p38MAPK appeared to be very rapidly down-regulated 2 min after removal of sodium salicylate. Interestingly, sodium salicylate-pretreated cells remained fully responsive to re-induction of p38MAPK activity by a second sodium salicylate stimulation or by other stresses, $H_2O$$_2$ and methyl jasmonate (MeJA), thereby indicating that sodium salicylate does not exhibit both homologous and heterologous desensitization. In contrast, pre-exposure to MeJA, $H_2O$$_2$, heat shock, or hyperosmotic stress reduced the responsiveness to subsequent homologous stimulation. Sodium salicylate was able to activate p38MAPK in cells desensitized by other heterologous p38MAPK activators. These results indicate that there is a sensing mechanism highly specific to sodium salicylate for activation of p38MAPK, distinct trom pathways used by other stressors such as MeJA, $H_2O$$_2$ heat shock, and hyperosmotic stress.

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Inhibitory Effect of $Zn^{+2}$ on Tolaasin-induced Hemolysis ($Zn^{+2}$에 의한 Tolaasin의 용혈활성 저해효과)

  • Cho, Kwang-Hyun;Kim, Sung-Tae;Kim, Young-Kee
    • Applied Biological Chemistry
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    • v.49 no.4
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    • pp.281-286
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    • 2006
  • Tolaasin, a pore-forming toxin, is a 1,985 Da peptide produced by Pseudomonas tolaasii and causes a brown blotch disease on cultivated mushrooms. Tolaasin forms pores on the plasma membrane of various cells including fungi, bacteria, plant as well as erythrocytes, and destroys cell structure. $Zn^{+2}$ has been known to block the tolaasin activity by an unknown mechanism. Thus, we investigated the inhibitory effects of $Zn^{+2}$ on the tolaasin-induced hemolysis to understand the molecular mechanism of tolaasin-induced pore formation. $Zn^{+2}$ and $Cd^{+2}$ inhibited the tolaasin-induced hemolysis in a dose-dependent manner and their Ki values were 170 ${\mu}M$ and 20 mM, respectively. The effect of $Zn^{+2}$ was reversible since the subsequent addition of EDTA chelates $Zn^{+2}$ and removes the inhibitory effect of $Zn^{+2}$. When an osmotic protectant, PEG 2000, was added, the tolaasin-induced hemolysis was not observed. After the removal of osmotic protectant by centrifugation, resuspended erythrocytes with fresh medium were immediately hemolyzed, while the addition of $Zn^{+2}$ prevented from hemolysis, implying that tolaasin-induced pores on the membrane were already formed in the medium containing osmotic protectant. These results suggest that $Zn^{+2}$ inhibits the activity of tolaasin pores and it has minor effects on the membrane binding of tolaasin and the formation of pore.

Studies on the Mechanism of Nonastringency and Production of Tannin in Persimmon Fruits -II. Microscopic Observation of Tannin Cells in Persimmon Fruits during Growth- (감과실(果實)의 탄닌물질(物質)의 생성(生成) 및 탈삽기구(脫澁機構)에 관(關)한 연구(硏究) -제2보 : 탄닌 세포(細胞)의 현미경적 관찰-)

  • Sohn, Tae-Hwa;Seong, Jong-Hwan
    • Korean Journal of Food Science and Technology
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    • v.13 no.4
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    • pp.261-266
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    • 1981
  • In order to clarify the removal of astringency in persimmon fruits (Diospyros koki L.) and its mechanism, a comparative histology of tannin cells in tile cultivars of astringent persimmon fruits (Sangju Dungsi. Daegu Bansi. Cheongdo Bansi) and a sweet persimmon fruit (Fuyu) was observed. Tannin cells were widespread in all fruits tissue expert for tissue of ovule before full blossom. The epidermal cells of ovary. flower and calyx consist of tannin cell. Arrangement of tannin cells has radiated type toward the upper directions in the calyx. The major part of seed coat consisted of tannin cells. The epidermal cells of persimmon fruits were consisted of small tannin cells, and the inner part of epicarp of the astringent persimmon was consisted of stone cells, but the sweet persimmon was consisted of parenchymatous cells. It was suggested that differantiation of tannin cell In persimmon fruits occured until about the middle of August. Some tannin cells of matured astringent persimmon fruits was coagulated and wall of tannin cell produced protuberance, and most of tannin cells of matured sweet persimmon fruits was coagulated or ruptured.

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