• Title/Summary/Keyword: Mass Science

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The First Photometric Study of NSVS 1461538: A New W-subtype Contact Binary with a Low Mass Ratio and Moderate Fill-out Factor

  • Kim, Hyoun-Woo;Kim, Chun-Hwey;Song, Mi-Hwa;Jeong, Min-Ji;Kim, Hye-Young
    • Journal of Astronomy and Space Sciences
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    • v.33 no.3
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    • pp.185-196
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    • 2016
  • New multiband BVRI light curves of NSVS 1461538 were obtained as a byproduct during the photometric observations of our program star PV Cas for three years from 2011 to 2013. The light curves indicate characteristics of a typical W-subtype W UMa eclipsing system, displaying a flat bottom at primary eclipse and the O'Connell effect, rather than those of an Algol/b Lyrae eclipsing variable classified by the northern sky variability survey (NSVS). A total of 35 times of minimum lights were determined from our observations (20 timings) and the SuperWASP measurements (15 ones). A period study with all the timings shows that the orbital period may vary in a sinusoidal manner with a period of about 5.6 yr and a small semi-amplitude of about 0.008 day. The cyclical period variation can be interpreted as a light-time effect due to a tertiary body with a minimum mass of 0.71 M. Simultaneous analysis of the multiband light curves using the 2003 version of the Wilson-Devinney binary model shows that NSVS 1461538 is a genuine W-subtype W UMa contact binary with the hotter primary component being less massive and the system shows a low mass ratio of q(mc/mh)=3.51, a high orbital inclination of 88.7°, a moderate fill-out factor of 30 %, and a temperature difference of ΔT=412 K. The O'Connell effect can be similarly explained by cool spots on either the hotter primary star or the cool secondary star. A small third-light corresponding to about 5 % and 2 % of the total systemic light in the B and V bandpasses, respectively, supports the third-body hypothesis proposed by the period study. Preliminary absolute dimensions of the system were derived and used to look into its evolutionary status with other W UMa binaries in the mass-radius and mass-luminosity diagrams. A possible evolution scenario of the system was also discussed in the context of the mass vs mass ratio diagram.

Analysis of Hanwoo Loin Proteome by 2-D Gel Electrophoresis and Peptide Mass Fingerprinting

  • Lim, Jin-Kyu;Pyo, Jae-Hoon;Lee, Hwa-Jin;Jung, Il-Jung;Park, Young-Sik;Yeo, Young-Kuen;Kim, Jeong-Sang
    • Preventive Nutrition and Food Science
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    • v.7 no.4
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    • pp.432-436
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    • 2002
  • A proteomic map of Hanwoo loin was obtained using 2-D SDS-PAGE and mass spectrometric analysis: 27 bovine proteins plus 2 proteins having similarities to other mammal proteins out of 52 proteins analyzed. The identified proteins consisted of 50 % basic house keeping proteins involved in metabolism, 30% muscle proteins, and other miscellaneous proteins. Many proteins on the 2-D gel with different molecular weights and isoelectric points were identified as same proteins due to posttranslational modification. As many of the identified house keeping proteins showed the high sequence similarities to other mammal equivalent proteins, searching the mammal databases could confirm the annotation. The preliminary identification of the proteome in bovine loin tissue could reveal the functions of proteins at over 50 % of chance with high fidelities. Using the established loin proteome map, proteomic difference between 1 yr and 2 yr Hanwoo loin tissues were compared on 2D gel. Regardless of the difficulty normalizing protein concentrations and sample-to-sample variations, three unidentified proteins and myoglobin were selected as up-regulated proteins during the fat deposition period. This study contributes to a move thorough and holistic understanding of beef meat, helping to build the basis for future identification of new markers for good quality meat.

Organic Acid Profiling Analysis in Culture Media of Lactic Acid Bacteria by Gas Chromatography-Mass Spectrometry

  • Lee, Jae-Yeon;Nguyen, Duc-Toan;Park, Young-Shik;Hwang, Kyo-Yeol;Cho, Yong-Seok;Kang, Kyung-Don;Yoon, Jae-Hwan;Yu, Jun-Dong;Yee, Sung-Tae;Ahn, Young-Hwan;Lee, Gwang;Seong, Su-Il;Paik, Man-Jeong
    • Mass Spectrometry Letters
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    • v.3 no.3
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    • pp.74-77
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    • 2012
  • Organic acid (OA) profiling analysis was performed in culture media from Lactobacillus pentosus K34 (L. pentosus K34) and Pediococcus lolli PL24 (P. lolli PL24) by gas chromatography-mass spectrometry (GC-MS) following methoxime/tert-butyldimethylsilyl derivatives. 12 OAs were positively identified in culture media. Most of OA levels from L. pentosus K34 of hetero lactic fermentation were found to be higher when compared with those from P. lolli PL24 of homo lactic fermentation, which may explain different OA metabolism in each strain. In addition, the distorted dodecagonal star patterns were readily distinguishable, and the characteristics of each strain were well represented. The present study demonstrates that the OA metabolic profiling method by GC-MS combined with star pattern recognition is useful for the monitoring study of characteristic OA metabolism in various microorganisms.

Direct Quantitation of Amino Acids in Human Serum Using a Stepwise-Dilution Strategy and a Mixed-Mode Liquid Chromatography-Tandem Mass Spectrometry Method

  • Lee, Jaeick;Lee, Seunghwa;Kim, Byungjoo;Lee, Joonhee;Kwon, Oh-Seung;Cha, Eunju
    • Mass Spectrometry Letters
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    • v.9 no.1
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    • pp.30-36
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    • 2018
  • A quantitation method for free amino acids in human serum was developed using a stepwise-dilution method and a bimodal cation exchange (CEX)/hydrophilic interaction liquid chromatography (HILIC)-tandem mass spectrometry system equipped with an electrospray ionization source (ESI/MS/MS). This method, which was validated using quality control samples, was optimized for enhanced selectivity and sensitivity. Dithiothreitol (DTT) was used as a reducing agent to prevent the oxidation of a serum sample ($50{\mu}L$), which was then subjected to stepwise dilution using 3, 30, and 90 volumes of acetonitrile containing 0.1% formic acid. Chromatographic separation was performed on an Imtakt Intrada Amino Acid column ($50mm{\times}3mm$, $3{\mu}m$) in mixed mode packed with CEX and HILIC ligands embedded in the stationary phase. Underivatized free amino acids were eluted and separated within 10 min. As a result of the validation, the precision and accuracy for the inter- and intraday assays were determined as 2.11-11.51% and 92.82-109.40%, respectively. The lowest limit of quantification (LLOQ) was $0.5-4.0{\mu}g/mL$ and the matrix effect was 80.22-115.93%. The proposed method was successfully applied to the quantitative analysis of free amino acids in human serum.

Low Muscle Mass and Depressed Mood in Korean Adolescents: a Cross-Sectional Analysis of the Fourth and Fifth Korea National Health and Nutrition Examination Surveys

  • Moon, Ji Hyun;Kong, Mi Hee;Kim, Hyeon Ju
    • Journal of Korean Medical Science
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    • v.33 no.50
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    • pp.320.1-320.8
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    • 2018
  • Background: Muscle mass and muscle function are related to depressed mood in studies of adults. Like adults, Korean students are highly likely to suffer from decreased muscle mass due to social conditions. In this study, we evaluated the muscle mass status of Korean adolescents and assess the effect of muscle on depressive mood. Methods: A total of 1,233 adolescent boys and girls participants from the Korea National Health and Nutrition Examination Survey were enrolled in our study. Participants underwent dual-energy X-ray absorptiometry for assessment of appendicular muscle mass and completed questionnaires regarding depressed mood, stress, suicidal ideations, and attempts. Results: There was no difference in depressive mood according to muscle mass among boys (P = 0.634); girls with decreased muscle mass had a greater tendency for depressed mood compared to girls with optimal muscle mass (P = 0.023). After adjusting for age, waist circumference-to-height ratio, smoking status, alcohol consumption, frequency of physical activity, self-reported obesity, weight-loss efforts, and monthly household income, girls with low muscle mass (LMM) were 2.60 times more at risk of developing depression than girls with normal muscle mass (95% confidence interval [CI], 1.05-6.49; P = 0.040). This trend was similar for girls with LMM with obesity (95% CI, 1.00-11.97; P = 0.049). Conclusion: Adolescent girls who have insufficient muscle mass are more likely to report depressed mood than girls who have ideal muscle mass. Interventions for maintaining proper muscle mass are required.

VELOCITY ANALYSIS OF M13 BY MAXIMUM LIKELIHOOD METHOD

  • Oh, K.S.;Lin, D. N. C.
    • Journal of The Korean Astronomical Society
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    • v.25 no.1
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    • pp.1-9
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    • 1992
  • We present new approach to analysis of velocity data of globular clusters. Maximum likelihood method is applied to get model parameters such as central potential, anisotropy radius, and total mass fractions in each mass class. This method can avoid problems in conventional binning method of chi-square. We utilize three velocity components, one from line of sight radial velocity and two from proper motion data. In our simplified scheme we adopt 3 mass-component model with unseen high mass stars, intermediate visible stars, and low mass dark remnants. Likelihood values are obtained for 124 stars in M13 for various model parameters. Our preferred model shows central potential of $W_o=7$ and anisotropy radius with 7 core radius. And it suggests non-negligible amount of unseen high mass stars and considerable amount of dark remnants in M13.

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Silicon Piezoresistive Acceleration Sensor with Compensated Square Pillar Type of Mass (사각뿔 형태의 Mass 보상된 실리콘 압저항형 가속도 센서)

  • Sohn, Byoung-Bok;Lee, Jae-Gon;Choi, Sie-Young
    • Journal of Sensor Science and Technology
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    • v.3 no.1
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    • pp.19-25
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    • 1994
  • When etching rectangular convex corners of silicon using anisotropic etchants such as KOH, deformation of the edges always occurs due to undercutting. Therefore, it is necessary to correct the mass pattern for compensation. Experiments for the compensation method to prevent this phenomenon were carried out. In the result, the compensation pattern of a regular square is suitable for acceleration sensors considering space. With this consequence, silicon piezoresistive acceleration sensor with compensated square pillar type of mass has been fabricated using SDB wafer.

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Continuous Viscosity Measurement of Non-Newtonian Fluids over a Range of Shear Rates Using a Mass-Detecting Capillary Viscometer

  • Sehyun Shin;Keum, Do-Young
    • Journal of Mechanical Science and Technology
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    • v.16 no.2
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    • pp.255-261
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    • 2002
  • A newly designed mass-detecting capillary viscometer uses a novel concept to continuously measure non-Newtonian fluids viscosity over a range of shear rates. A single measurement of liquid-mass variation with time replaces the now rate and pressure drop measurements that are usually required by capillary tube viscometers. Using a load cell and a capillary, we measured change in the mass flow rate through a capillary tube with respect to the time, m(t), from which viscosity and shear rate were mathematically calculated. For aqueous polymer solutions, excellent agreement was found between the results from the mass-detecting capillary viscometer and those from a commercially available rotating viscometer. This new method overcomes the drawbacks of conventional capillary viscometers meassuring non-Newtonian fluid viscosity. First, the mass-detecting capillary viscometer can accurately and consistently measure non -Newtonian viscosity over a wide range of shear rate extending as low as 1 s$\^$-1/. Second, this design provides simplicity (i. e., ease of operation, no moving parts), and low cost.

Diaphragmatic deformity in a cat mimicking a cardiac mass

  • Choi, Ran;Lee, Seung-Gon;Moon, Hyeong-Sun;Hyun, Changbaig
    • Korean Journal of Veterinary Research
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    • v.48 no.2
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    • pp.209-213
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    • 2008
  • A four-month-old intact femlae Abyssinian cat was present for routine health evaluation, because her littermate was recently died of ventricular septal defect. Diagnostic imaging studies showed a large caudal paracardiac mass in thoracic radiography and homogenous mass adjacent to heart in the echocardiography. Further echographic study revealed that the mass was liver and the diaphragmatic line was intact. The positive contrast celiogram revealed that no extravasation of the contrast media across the diaphragm and the prolapse of diaphragm into the pleural cavity. Based on our diagnostic imaging studies, the case was diagnosed as diaphragmatic deformity in a cat mimicking a cardiac mass.

Smart tuned mass dampers: recent developments

  • Nagarajaiah, Satish;Jung, Hyung-Jo
    • Smart Structures and Systems
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    • v.13 no.2
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    • pp.173-176
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    • 2014
  • This special issue focuses on Smart Tuned Mass Dampers (STMD) that are either active or smart or semi-active in nature. Active tuned mass dampers or active mass dampers have found wide acceptance and have been implemented in many tall buildings and long span bridges. Recently researchers have developed a new class of smart tuned mass dampers using either variable stiffness and/or variable damping to effect the change in instantaneous frequency and damping. Since tuning plays a central role in STMDs it is of great current interest thus the topic of this special issue. Discussions of recent active and smart TMD implementations in tall buildings and bridges are also included.