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Preparation of Disulfonated Poly(arylene ether sulfone) Random Copolymer Thin Film Composite Membranes Using a Benign Solvent (친환경용매 기반의 술폰화 폴리아릴렌 에테르 술폰 랜덤 공중합체 Thin Film Composite 제조)

  • Lee, Chang Hyun;McGrath, James E.;Freeman, Benny
    • Membrane Journal
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    • v.24 no.4
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    • pp.292-300
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    • 2014
  • Chlorine-resistant sulfonated poly(arylene ether sulfone) random copolymer (SPAES)-thin film composite (TFC) membranes for desalination are prepared using monoglyme as a selective solvent, which dissolves SPAES, but should be inert to porous polysulfone layer (e.g., Udel$^{(R)}$). Different from formic acid and diethylene glycol used as other selective solvents, monoglyme is environmentally friendly and has much lower boiling temperature. After a pretreatment of Udel$^{(R)}$ support film in isopropyl alcohol-glycerine mixture to minimize pore penetration leading to fairly reduced water flux, coating of SPAES solution in monoglyme onto the support and stepwise drying processes are conducted for defect-free TFC formation. The transport behavior through SPAES-TFC membranes is observed, correlating with the effects of sulfonation level, protonation, and physical and chemical crosslinking of SPAES selective layers.

Incidental findings of temporomandibular joint osteoarthritis and its variability based on age and sex

  • Alzahrani, Adel;Yadav, Sumit;Gandhi, Vaibhav;Lurie, Alan G.;Tadinada, Aditya
    • Imaging Science in Dentistry
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    • v.50 no.3
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    • pp.245-253
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    • 2020
  • Purpose: This study investigated the prevalence of temporomandibular joint osteoarthritis (TMJ-OA) using the Research Diagnostic Criteria for Temporomandibular Disorders image analysis criteria, assessed the severity of incidental osteoarthritic changes affecting the TMJ, and evaluated the correlations of sex and age with the prevalence and severity of TMJ-OA. Materials and Methods: This retrospective study assessed 145 randomly selected cone-beam computed tomography scans (261 TMJs) from the authors' institutional maxillofacial radiology archive following the application of inclusion and exclusion criteria. The criteria described by Ahmad et al. were used to determine whether each TMJ was affected by OA, and the severity of the osteoarthritic changes was scored for each joint based on the method described by Alexiou et al. The chi-square, McNemar, Bhapkar chi-square, and Stuart-Maxwell chi-square tests were applied to evaluate the significance of the relationships between variables(age and sex). Results: Sixteen TMJs (6.1%) had no OA, 74 (28.6%) were indeterminate for OA, and 171 (65.5%) had OA. Flattening and sclerosis were observed in 86.6% and 12.3% of cases, respectively, while resorption was observed in 7.3% of the joints. Only 21 (8.1%) of the examined TMJs had subchondral cysts. Erosion of the articular eminence was observed in 58 (22.1%) cases, while sclerosis and resorption were found in 68 (25.9%) and 16 (6.1%) TMJs, respectively. Conclusion: Female patients had a higher prevalence and severity of TMJ-OA than male patients. The prevalence and severity of TMJ-OA increased with age, with peaks in the fifth and seventh decades of life.

The effect of repeated firings on the color change of dental ceramics using different glazing methods

  • Yilmaz, Kerem;Gonuldas, Fehmi;Ozturk, Caner
    • The Journal of Advanced Prosthodontics
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    • v.6 no.6
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    • pp.427-433
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    • 2014
  • PURPOSE. Surface color is one of the main criteria to obtain an ideal esthetic. Many factors such as the type of the material, surface specifications, number of firings, firing temperature and thickness of the porcelain are all important to provide an unchanged surface color in dental ceramics. The aim of this study was to evaluate the color changes in dental ceramics according to the material type and glazing methods, during the multiple firings. MATERIALS AND METHODS. Three different types of dental ceramics (IPS Classical metal ceramic, Empress Esthetic and Empress 2 ceramics) were used in the study. Porcelains were evaluated under five main groups according to glaze and natural glaze methods. Color changes (${\Delta}E$) and changes in color parameters (${\Delta}L$, ${\Delta}a$, ${\Delta}b$) were determined using colorimeter during the control, the first, third, fifth, and seventh firings. The statistical analysis of the results was performed using ANOVA and Tukey test. RESULTS. The color changes which occurred upon material-method-firing interaction were statistically significant (P<.05). ${\Delta}E$, ${\Delta}L$, ${\Delta}a$ and ${\Delta}b$ values also demonstrated a negative trend. The MC-G group was less affected in terms of color changes compared to other groups. In all-ceramic specimens, the surface color was significantly affected by multiple firings. CONCLUSION. Firing detrimentally affected the structure of the porcelain surface and hence caused fading of the color and prominence of yellow and red characters. Compressible all-ceramics were remarkably affected by repeated firings due to their crystalline structure.

Preliminary Result from Rapid Cadence Photometric Monitoring of HBC722

  • Baek, Gi-Seon;Green, Joel D.;Pak, Soo-Jong;Lee, Jeong-Eun;Eon, Yi-Seulj;Park, Won-Kee;Choi, Chang-Su;Kang, Won-Seok;Im, Myung-Shin
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.113.2-113.2
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    • 2011
  • We observed a low-mass pre-main sequence star, HBC722 (also known as $LkH{\alpha}$ 188 G4), with Camera for QUasars in EArly uNiverse (CQUEAN) attached to 2.1 Otto Struve telescope at McDonald Observatory, USA. HBC722 is a new FU orionis-type object in the direction of NGC7000/IC5070, which produced large amplitude optical outbursts (${\delta}V$=4.7 mag over one year) for a few months and reached the peak in 2010 September. We carried out the photometric observation in SDSS r,i, and z band in 2011 April, July and August to monitor the long term decrease of its brightness. We also made continuous observation in r-band for half night in July, and whole two nights in August to investigate short term variability which could be related to the rotation of the central star or the inner circumstellar disk. In this poster, we present a preliminary result of the photometric observation for HBC722.

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Selection of Capillary Tubes for HCFC-22 Alternative Fluids (HCFC-22 대체냉매의 모세관 선정)

  • Jung, D.S.;Kim, C.B.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.7 no.3
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    • pp.435-449
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    • 1995
  • In this paper, pressure drop through a capillary tube is modeled to determine the length of a capillary tube for a given set of conditions. HCFC-22 and its alternatives, HFC-134a, R407B, and R410A are used as working fluids. The conditions on which the model is tested are as follows : condensing temperature; 40.0, 45.0, 50.0, $55.0^{\circ}C$, degree of subcooling;0.0, 2.5, $5.0^{\circ}C$, capillary tube exit condition;choked flow, capillary tube diameter;1.2~2.4mm, mass flow rate;5.0~50.0g/sec. The results justify the use of Stoecker's model which yields the results very close to the values in ASHRAE handbook. While McAdams' method yields much better results than Duckler's in calculating the viscosity of the fluid in 2-phase, the friction factor suggested by Stoecker seems to be the best for capillary tubes of large diameter used in residential air conditioners. For each refrigerant, 372 data with various variables are calculated by the model. The results show that capillary tube length varies very uniformly with changes in condensing temperature and degree of subcooling. Based on this fact, regression analysis is performed to determine the dependence of mass flow rate on the length and diameter of a capillary tube, condensing temperature, and degree of subcooling. Thus determined correlation yields a mean deviation of 2.36% for 1,488 data, showing an excellent agreement.

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Mechanical design of mounts for IGRINS focal plane array

  • Oh, Jae Sok;Park, Chan;Cha, Sang-Mok;Yuk, In-Soo;Park, Kwijong;Kim, Kang-Min;Chun, Moo-Young;Ko, Kyeongyeon;Oh, Heeyoung;Jeong, Ueejeong;Nah, Jakyuong;Lee, Hanshin;Pavel, Michael;Jaffe, Daniel T.
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.53.2-53.2
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    • 2014
  • IGRINS, the Immersion GRating INfrared Spectrometer, is a near-infrared wide-band high-resolution spectrograph jointly developed by the Korea Astronomy and Space Science Institute and the University of Texas at Austin. IGRINS employs three HAWAII-2RG focal plane array (FPA) detectors. The mechanical mounts for these detectors serves a critical function in the overall instrument design: Optically, they permit the only positional compensation in the otherwise "build to print" design. Thermally, they permit setting and control of the detector operating temperature independently of the cryostat bench. We present the design and fabrication of the mechanical mount as a single module. The detector mount includes the array housing, a housing for the SIDECAR ASIC, a field flattener lens holder, and a support base. The detector and ASIC housing will be kept at 65 K and the support base at 130 K. G10 supports thermally isolate the detector and ASIC housing from the support base. The field flattening lens holder attaches directly to the FPA array housing and holds the lens with a six-point kinematic mount. Fine adjustment features permit changes in axial position and in yaw and pitch angles. We optimized the structural stability and thermal characteristics of the mount design using computer-aided 3D modeling and finite element analysis. Based on the computer simulation, the designed detector mount meets the optical and thermal requirements very well.

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Expression and DNA Sequence of the Gene Coding for the lux-specific Fatty Acyl-CoA Reductase from photobacterium phosphoreum

  • Lee, Chan-Yong;Edward A. Meighen
    • Journal of Microbiology
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    • v.38 no.2
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    • pp.80-87
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    • 2000
  • The nucleotide sequence of the luxC gene coding for lux-specific fatty acyl-CoA reductase and the upstream DNA (325bp)of the structural gene from bioluminescent bacterium, Photobacterium phosphoreum, has been deternubed. An open reading frame extending for more than 20 codons in 325 bp DNA upstream of luxC was not present in both directions. The lux gene can be translated into a polypeptide of 54 kDa and the amino acid sequences of lux specific reductases of P. phosphoreum shares 80, 65, 58, and 62% identity with those of the Photobacterium leiognathi, Vibrio fischeri, Vibrio harveyi, and Xehnorhabdus luminescenens reductases, respectively. Analyses of codon usage, showing that a high frequency (2.3%) of the isoleucine codon, AUA, in the luxC gene compared to that found in Escherichia coli genes (0.2%) and its absence in the luxA and B genes, suggested that the AUA codon may play a modulator role in the expression of lux gene in E. coli. The structural genes (luxC, D, A, B, E) of the P. phosphoreum coding for luciferase (${\alpha}$,${\beta}$) and fatty acid reductase (r, s, t) polypeptides can be expressed exclusively in E. coli under the T7 phage RNA polymerase/promoter system and identificationof the [35S]methionine labelled polypeptide products. The degree of expression of lux genes in analyses of codon usage. High expression of the luxC gene could only be accomplished in a mutant E. coli 43R. Even in crude extracts, the acylated acyl-CoA reductase intermediate as well as acyl-CoA reductrase activities could be readily detected.

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A Study on the Occurrence of Benzo(a)pyrene in Fats and Oils by Heat Treatment(II) (油脂加熱시 Benzo(a)pyrene 生成에 관한 硏究(II) -닭튀김 및 튀김유 중에서-)

  • Kim, In-Sook;Ahn, Myung-Soo
    • Korean journal of food and cookery science
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    • v.10 no.3
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    • pp.301-307
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    • 1994
  • Benzo(a)pyrene [B(a)P], one of the polycyclic aromatic hydrocarbons(PAHs) is know as a potent careinogen. As consumption of lipid food and fried food increases recently, the toxic effect of overheated lipid foods has report increasingly. This study was undertaken to measure the contents of B(a)P and other PAHs of fried chicken and frying oil. At the same time, the rancidities of frying oil and descarded oil were determined. B(a)P and other PAHs contents of all samples were measured by HPLC/UV method. The results obtained were as follows; B(a)P contents of fresh chicken and soybean oil were 0.073 and 0.146 ${\mu}$g/kg, respectively. During fried chicken at 180${\pm}$5$^{\circ}C$ and 200${\pm}$5$^{\circ}C$, B(a)P and PAHs contens decreased or increased In 20 times fried chicken, PAHs contents except Pyr and DMBA increased at 180${\pm}$5$^{\circ}C$ and PAHs contents except DMBA, DBA, and 3-MC increased at 200${\pm}$5$^{\circ}C$. In frying oils fried chicken, PAHs contents increased in 10 and 15 times frying oil at 180${\pm}$5$^{\circ}C$ and grew more increase and more increase during frying at 200${\pm}$5$^{\circ}C$. The changing pattern of PAHs contents of frying oils was remotely related that of rancidities of frying oils. In fried chicken, frying oils, and discarded oils obtained from fried chicken house at market, PAHs contents of fried chickens were lower than those of fried chicken cooked at laboratory but those of frying oils and discarded oils were higher than those of frying oils cooked at laboratory.

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Temporal Trends and Future Prediction of Breast Cancer Incidence Across Age Groups in Trivandrum, South India

  • Mathew, Aleyamma;George, Preethi Sara;Arjunan, Asha;Augustine, Paul;Kalavathy, MC;Padmakumari, G;Mathew, Beela Sarah
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.6
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    • pp.2895-2899
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    • 2016
  • Background: Increasing breast cancer (BC) incidence rates have been reported from India; causal factors for this increased incidence are not understood and diagnosis is mostly in advanced stages. Trivandrum exhibits the highest BC incidence rates in India. This study aimed to estimate trends in incidence by age from 2005-2014, to predict rates through 2020 and to assess the stage at diagnosis of BC in Trivandrum. Materials and Methods: BC cases were obtained from the Population Based Cancer Registry, Trivandrum. Distribution of stage at diagnosis and incidence rates of BC [Age-specific (ASpR), crude (CR) and age-standardized (ASR)] are described and employed with a joinpoint regression model to estimate average annual percent changes (AAPC) and a Bayesian model to estimate predictive rates. Results: BC accounts for 31% (2681/8737) of all female cancers in Trivandrum. Thirty-five percent (944/2681) are <50 years of age and only 9% present with stage I disease. Average age increased from 53 to 56.4 years (p=0.0001), CR (per $10^5$ women) increased from 39 (ASR: 35.2) to 55.4 (ASR: 43.4), AAPC for CR was 5.0 (p=0.001) and ASR was 3.1 (p=0.001). Rates increased from 50 years. Predicted ASpR is 174 in 50-59 years, 231 in > 60 years and overall CR is 80 (ASR: 57) for 2019-20. Conclusions: BC, mostly diagnosed in advanced stages, is rising rapidly in South India with large increases likely in the future; particularly among post-menopausal women. This increase might be due to aging and/or changes in lifestyle factors. Reasons for the increased incidence and late stage diagnosis need to be studied.

Inhibitors of AKT Signaling Pathway and their Application

  • WONG, Chin Piow
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.04a
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    • pp.33-33
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    • 2019
  • The AKT signaling pathway is a highly regulated cell signaling system that forms a network with other cell signaling pathways. Hence, the AKT signaling pathway mediates several important cellular functions that include cell survival, proliferation, cell migration, and et cetera. Irregularities that led overactive AKT signaling have been linked to many diseases such as cancer and metabolic-associated diseases. Hence, modulating the overactive AKT signaling pathway via inhibitor is a tantalizing prospect for treatment of cancer and metabolic-associated diseases. Two inhibitors of the AKT signaling pathway will be presented in this symposium: 1) Bisleuconothine A (BisA), a bisindole alkaloid that inhibit autophagy and 2) Ceramicine B (CerB), a limonoid that inhibit adipogenesis. The first topic is on a bisindole alkaloid, BisA and its mechanism in inducing autophagosome formation in lung cancer cell line, A549.(1) Since most autophagy inducing agents generally induce apoptosis, we found that BisA does not induce apoptosis even in high dose. BisA up-regulation of LC3 lipidation is achieved through mTOR inactivation. The phosphorylation of PRAS40, a mTOR repressor was suppressed by BisA. This observation suggested that BisA inactivates mTOR via suppression of PRAS40 phosphorylation. Interestingly, the phosphorylation of AKT, an upstream regulator of PRAS40 phosphorylation was also down-regulated by BisA. These findings suggested that Bis-A induces autophagosomes formation by interfering with the AKT-mTOR signaling pathway. The second topic is on CerB and its mechanism in inhibiting adipogenesis in preadipocytes cell line, MC3T3-G2/PA6.(2,3) CerB inhibits the phosphorylation of protein kinase B (AKT) at the Thr308 position but not the Ser473. Consequently, the phosphorylation of FOXO3 which is located downstream of AKT is also inhibited. Considering that FOXO3 is an important regulator of PPARγ which is a key factor in adipogenesis, CerB may inhibit adipogenesis via the AKT-FOXO3 signaling pathway. Taken together, both BisA and CerB highlighted the potential of AKT signaling pathway modulation as an approach to induce autophagy and inhibit the formation of fat cells, respectively.

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