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STM Tip Catalyzed Adsorption of Thiol Molecules and Functional Group-Selective Adsorption of a Bi-Functional Molecule Using This Catalysis

  • Min, Yeong-Hwan;Jeong, Sun-Jeong;Yun, Yeong-Sang;Park, Eun-Hui;Kim, Do-Hwan;Kim, Se-Hun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.197-197
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    • 2011
  • In this study, in contrast with cases in which Scanning Tunneling Microscopy (STM) tip-induced reactions were instigated by the tunneling electrons, the local electric field, or the mechanical force between a tip and a surface, we found that the tungsten oxide (WO3) covered tungsten (W) tip of a STM acted as a chemical catalyst for the S-H dissociative adsorption of phenylthiol and 1-octanethiol onto a Ge(100) surface. By varying the distance between the tip and the surface, the degree of the tip-catalyzed adsorption could be controlled. We have found that the thiol head-group is the critical functional group for this catalysis and the catalytic material is the WO3 layer of the tip. After removing the WO3 layer by field emission treatment, the catalytic activity of the tip has been lost. 3-mercapto isobutyric acid is a chiral bi-functional molecule which has two functional groups, carboxylic acid group and thiol group, at each end. 3-Mercapto Isobutyric Acid adsorbs at Ge(100) surface only through carboxylic acid group at room temperature and this adsorption was enhanced by the tunneling electrons between a STM tip and the surface. Using this enhancement, it is possible to make thiol group-terminated surface where we desire. On the other hand, surprisingly, the WO3 covered W tip of STM was found to act as a chemical catalyst to catalyze the adsorption of 3-mercapto isobutyric acid through thiol group at Ge(100) surface. Using this catalysis, it is possible to make carboxylic acid group-terminated surface where we want. This functional group-selective adsorption of bi-functional molecule using the catalysis may be used in positive lithographic methods to produce semiconductor substrate which is terminated by desired functional groups.

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A Biomechanical Comparison among Three Surgical Methods in Bilateral Subaxial Cervical Facet Dislocation

  • Byun, Jae-Sung;Kim, Sung-Min;Choi, Sun-Kil;Lim, T. Jesse;Kim, Daniel H.
    • Journal of Korean Neurosurgical Society
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    • v.37 no.2
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    • pp.89-95
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    • 2005
  • Objective: The biomechanical stabilities between the anterior plate fixation after anterior discectomy and fusion (ACDFP) and the posterior transpedicular fixation after ACDF(ACDFTP) have not been compared using human cadaver in bilateral cervical facet dislocation. The purpose of this study is to compare the stability of ACDFP, a posterior wiring procedure after ACDFP(ACDFPW), and ACDFTP for treatment of bilateral cervical facet dislocation. Methods: Ten human spines (C3-T1) were tested in the following sequence: the intact state, after ACDFP(Group 1), ACDFPW(Group 2), and ACDFTP(Group 3). Intervertebral motions were measured by a video-based motion capture system. The range of motion(ROM) and neutral zone(NZ) were compared for each loading mode to a maximum of 2.0Nm. Results: ROMs for Group 1 were below that of the intact spine in all loading modes, with statistical significance in flexion and extension, but NZs were decreased in flexion and extension and slightly increased in bending and axial rotation without significances. Group 2 produced additional stability in axial rotation of ROM and in flexion of NZ than Group 1 with significance. Group 3 provided better stability than Group 1 in bending and axial rotation, and better stability than Group 2 in bending of both ROM and NZ. There was no significant difference in extension modes for the three Groups. Conclusion: ACDFTP(Group 3) demonstrates the most effective stabilization followed by ACDFPW(Group 2), and ACDFP(Group 1). ACDFP provides sufficient strength in most loading modes, ACDFP can provide an effective stabilization for bilateral cervical facet dislocation with a brace.

Lobaplatin-TACE Combined with Radioactive 125I Seed Implantation for Treatment of Primary Hepatocellular Carcinoma

  • Peng, Sheng;Yang, Qiu-Xia;Zhang, Tao;Lu, Ming-Jian;Yang, Guang;Liu, Zhen-Yin;Zhang, Rong;Zhang, Fu-Jun
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.13
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    • pp.5155-5160
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    • 2014
  • Aim: To investigate the efficacy and safety of lobaplatin-transcatheter arterial chemoembolization (TACE) combined with radioactive $^{125}I$ seed implantation in treatment of primary hepatocellular carcinoma (HCC). Methods: 75 patients with primary HCC were enrolled in the study, among them 43 receiving lobaplatin-TACE (TACE group) and 32 lobaplatin-TACE combined with $^{125}I$ seed implantation (TACE+$^{125}I$ group). After treatment, the local remission rates and postoperative complications of two groups were compared using the Pearson Chi-square test. Overall survival in the two groups was calculated using Kaplan-Meier survival curves and the differences were tested using Log-rank test. Results: There were 7 cases of complete response (CR), 13 of partial response (PR), 6 of stable disease (SD) and 17 of progressive disease (PD) in the TACE group, with 13 cases of CR, 9 of PR, 5 of SD and 5 of PD in the TACE+$^{125}I$ group. The disease control rates of TACE and TACE+$^{125}I$ group were 60.5% (26/43) and 84.4% (27/32), respectively, with a significant difference between them (P < 0.05). The survival rates at 6, 12 and 18 months in the TACE group were 100.0%, 81.8% and 50.0%, respectively, and those in TACE+$^{125}I$ group were 100.0%, 93.8% and 65.6%. The mean survival times in the TACE and TACE+$^{125}I$ groups were 19.5 and 22.9 months, respectively. There was a significant difference in the overall survival rate between two groups (P < 0.05). No serious complications were encountered in either group. Conclusion: Lobaplatin-TACE combined with $^{125}I$ seed implantation is favorable and safe for treatment of primary HCC.

Immediate Effects of Lumbar Rotational Mobilization on the One-Legged Standing Ability in Healthy Individuals: A Randomized Controlled Trial

  • Heo, Seo Yoon;Kim, Bo Kyung;Moon, Ok Kon;Choi, Wan Suk
    • Journal of International Academy of Physical Therapy Research
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    • v.9 no.3
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    • pp.1521-1527
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    • 2018
  • The original focus of this study was to investigate the immediate effects of lumbar rotational mobilization on the one-legged standing ability. Fifteen subjects (6 men and 9 women, mean age = 22.77 (SD = 1.21), mean height = 165.46cm (SD = 11.65), mean weight = 61.46kg (SD = 8.29) volunteers from healthy individuals were recruited and randomized to a lumbar rotational mobilization (LRM) group and a trunk rotational exercise (TRE) group. Mobilization (grade 3 or 4) was applied to the LRM group on the lumbar spine (L1 to L5) in a side-lying, and trunk twist exercise (left and right side) was applied the to the TRE group with lunge position. Center of pressure (COP) and the velocity of the center of pressure (VCOP) of each participant were measured as a balance ability through one leg standing position. Results are as follows. In within-group difference, the COP of the LRM group reduced during standing with the right foot, but the VCOP change of the LRM was not statistically significant. In between-groups difference, COP of TRE group was decreased compared with LRM group only during left leg standing in the eyes (p <.05). The results of this study suggest that LRM is more effective than TRE in improving balance ability.

Effectiveness of caries-preventing agents on initial carious lesions within the scope of orthodontic therapy

  • Park, Kyung-Jin;Kroker, Tessa;Gross, Uwe;Zimmermann, Ortrud;Krause, Felix;Haak, Rainer;Ziebolz, Dirk
    • The korean journal of orthodontics
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    • v.49 no.4
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    • pp.246-253
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    • 2019
  • Objective: To evaluate the effectiveness of three different caries-preventing agents on artificial caries in a Streptococcus mutans-based caries model. Methods: Sixty-five caries-free human molar enamel blocks were treated with a demineralization solution and a remineralization solution. The specimens were assigned to the following groups according to the caries-protective product applied: group A, chlorhexidine varnish; group B, fluoride-releasing chemically cured sealant; group C, fluoride-releasing lightcured sealant; group D, positive control (specimens that were subjected to de- and remineralization cycles without treatment with any caries-protective agents); and group E, negative control (specimens that were not subjected to de- and remineralization cycles). Samples in groups A-D were stored in demineralization solution with S. mutans and thereafter in artificial saliva. This procedure was performed for 30 days. Average fluorescence loss (${\Delta}F$) and surface size of the lesions were measured using quantitative light-induced fluorescence at baseline and on the 7th, 14th, and 30th days. Results: After 30 days, group A demonstrated a significant increase in ΔF and the surface size of the lesions, no significant difference in comparison with the positive control group, and a significant difference in comparison with the negative control group. Group B showed no significant changes in both parameters at any of the measurement points. While group C showed increased ${\Delta}F$ after 14 days, no significant fluorescence change was observed after 30 days. Conclusions: Both fluoride-releasing sealants (chemically or light-cured) show anti-cariogenic effects, but the use of chlorhexidine varnish for the purpose of caries protection needs to be reconsidered.

The Effects of Resveratrol on Silica-Induced Lung Oxidative Stress and Inflammation in Rat

  • Maryam Esfahani;Amir Hossein Rahbar;Sara Soleimani Asl;Saed Bashirian;Effat Sadat Mir Moeini;Fereshteh Mehri
    • Safety and Health at Work
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    • v.14 no.1
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    • pp.118-123
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    • 2023
  • Background: Chronic exposure to silica is related with the provocation of an inflammatory response and oxidative stress mechanism. Vitamin D has multiple benefits in biological activities particularly respiratory system disease. Method: In this research, 20 male Wistar rats were randomly allocated into four groups (5 rats /group) as follow: Group1 received saline as (negative control) group. The group 2 received a single IT instillation of silica (positive control) group; the group 3 was co-administrated with single IT silica and Vitamin D (20 mg/kg/day) daily for a period of 90 days. The rats of group 4 received Vitamin D daily for a period of 90 days. Results: Silica significantly increased serum and lung total Oxidant Status (TOS). Meanwhile, silica reduced serum and lung total antioxidant capacity (TAC), GSH and tumor necrosis factor-α (TNF-a). Vitamin D treatment meaningfully reversed oxidative stress, antioxidants status and inflammatory response. Also, Vitamin D improved histopathological changes caused by silica. Conclusion: These findings indicate that Vitamin D exerts protective effects against silica-induced lung injury. It seems that Vitamin D has potential use as a therapeutic object for silica induced lung injure.

Induction of a Mutant, Monascus anka 732Y3 from Monascus anka KFCC 11832 and its Morphological Observations

  • Kim, Jun-Sung;Choi, Kee-Hyun;Choi, Jang-Yoon;Lee, Yoon-Soo;Chang, Young-Youl
    • Journal of Microbiology and Biotechnology
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    • v.3 no.2
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    • pp.134-138
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    • 1993
  • Monascus anka 732Y3 was induced from Monascus anka KFCC 11832 (IFO 4478, ATCC 16360) by ultra-violet light irradiation. The growth of this new fungus is frequently more dependent on sexual propagation than asexual propagation, compared with that of its parental strain, M. anka KFCC 11832. Less conidia than those of M. anka KFCC 11832 were observed by a microscope. The optical density of the red pigments ($OD_{500}$) produced by M. anka 732Y3 was 157, which was about 10 times higer than that of M. anka KFCC 11832. Such high production of the red pigments by the mutant could be explained by the following observations.

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A Laboratory-Scale Study of the Applicability of a Halophilic Sediment Bioelectrochemical System for in situ Reclamation of Water and Sediment in Brackish Aquaculture Ponds: Establishment, Bacterial Community and Performance Evaluation

  • Pham, Hai The;Tran, Hien Thi;Vu, Linh Thuy;Dang, Hien The;Nguyen, Thuy Thu Thi;Dang, Thu Ha Thi;Nguyen, Mai Thanh Thi;Nguyen, Huy Quang;Kim, Byung Hong
    • Journal of Microbiology and Biotechnology
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    • v.29 no.7
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    • pp.1104-1116
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    • 2019
  • In this study, we investigated the potential of using sediment bioelectrochemical systems (SBESs) for in situ treatment of the water and sediment in brackish aquaculture ponds polluted with uneaten feed. An SBES integrated into a laboratory-scale tank simulating a brackish aquaculture pond was established. This test tank and the control (not containing the SBES) were fed with shrimp feed in a scheme that mimics a situation where 50% of feed is uneaten. After the SBES was inoculated with microbial sources from actual shrimp pond sediments, electricity generation was well observed from the first experimental week, indicating successful enrichment of electrochemically active bacteria in the test tank sediment. The electricity generation became steady after 3 weeks of operation, with an average current density of $2.3mA/m^2$ anode surface and an average power density of $0.05mW/m^2$ anode surface. The SBES removed 20-30% more COD of the tank water, compared to the control. After 1 year, the SBES also reduced the amount of sediment in the tank by 40% and thus could remove approximately 40% more COD and approximately 52% more nitrogen from the sediment, compared to the control. Insignificant amounts of nitrite and nitrate were detected, suggesting complete removal of nitrogen by the system. PCR-DGGE-based analyses revealed the dominant presence of Methylophilus rhizosphaerae, Desulfatitalea tepidiphila and Thiothrix eikelboomii, which have not been found in bioelectrochemical systems before, in the bacterial community in the sediment of the SBES-containing tank. The results of this research demonstrate the potential application of SBESs in helping to reduce water pollution threats, fish and shrimp disease risks, and thus farmers' losses.

Efficiency of laser-assisted intracytoplasmic sperm injection in a human assisted reproductive techniques program

  • Choi, Kyoung-Hee;Lee, Jung-Hyun;Yang, Yun-Hee;Yoon, Tae-Ki;Lee, Dong-Ryul;Lee, Woo-Sik
    • Clinical and Experimental Reproductive Medicine
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    • v.38 no.3
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    • pp.148-152
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    • 2011
  • Objective: Laser-assisted intracytoplasmic sperm injection (LA-ICSI), also known as micro-opening or thinning of the zona pellucida (ZP) prior to ICSI, may help to reduce mechanical damage to the oocyte during the procedure. The aim of the present study was to evaluate and analyze the efficacy of our institutional LA-ICSI program, which features laser-assisted ZP thinning prior to ICSI, in comparison with conventional ICSI (C-ICSI), performed on patients with different clinical characteristics. Methods: Patients undergoing a total of 212 ICSI cycles were randomly divided into an LA-ICSI group (106 cycles) and a conventional ICSI group (106 cycles). To reduce tissue damage, we thinned the ZP by approximately 70%, using a laser, before ICSI. Patients thus treated formed the LAICSI group. Comparisons included the morphological quality of transferred embryos, blastocyst development of the remaining embryos, and clinical pregnancy, in terms of ICSI method and patient characteristics. Results: Fertilization, development of remaining embryos, and pregnancy rate were significantly higher in the LA-ICSI group compared with the C-ICSI group. Fertilization, embryonic development, and the pregnancy rate were all improved in younger patients (<38 years of age) and in those who underwent a low number of IVF-ET attempts (<3 trials). In addition, the pregnancy rate was increased in older patients. Conclusion: LA-ICSI may be useful in improving the chance of pregnancy in all ICSI patients.

Experimental Study on Spin Coated Thin Cover Layer for High Numerical Aperture Optical Disc

  • Dohoon Chang;Myongdo Ro;Duseop Yoon;Park, Insik;Dongho Shin;Kim, Jinhwan
    • Macromolecular Research
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    • v.9 no.6
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    • pp.313-318
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    • 2001
  • The present study relates to a method of manufacturing 100$\mu\textrm{m}$ thick cover layer for the high density digital versatile disc system (HD-DVD), which uses a high numerical aperture of 0.85 at 405 nm wavelength. Spin coating technique was investigated as means for manufacturing the cover layer within sufficient margins of thickness variation and with good mechanical properties including small radial and tangential tilts. The influence of processing variables such as spinning speed, spinning time, and dispensing position was investigated. The effect of viscosity of UV-curable resin was also investigated.

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