• Food Science of Animal Resources
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• v.41 no.5
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• pp.816-825
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• 2021

This study aims to validate a fast method of simultaneous analysis of 365 LCamenable and 142 GC-amenable pesticides in hen eggs by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS), respectively, operating in multiple reaction monitoring (MRM) acquisition modes. The sample preparation was based on quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction. Key method performance parameters investigated were specificity, linearity, limit of quantification (LOQ), accuracy, precision and measurement uncertainty. The method was validated at two spiking levels (10 and 50 ㎍/kg), and good recoveries (70%-120%) and relative standard deviations (RSDs) (≤20) were achieved for 92.9% of LC-amenable and 86.6% of GC-amenable pesticide residues. The LOQs were ≤10 ㎍/kg for 94.2% of LC-amenable and 92.3% of GC-amenable pesticides. The validated method was further applied to 100 egg samples from caged hens, and none of the pesticides was quantified.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.2
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• pp.55-60
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• 2011

Most of neural network chips use an analog-type maximum selector circuit (MS). As the increase of integration level, the analog MS has difficulties in achieving sufficient resolution. Contrary, the digital-type MS is easy to get high resolution but slower than its analog counterparts. A new high-speed digital MS circuit called MSIT (Maximum Selector with Internal Trigger-signal) is presented in this paper. The MSIT has been designed to achieves both the high reliability by using trigger-signals and high speed by removing the unnecessary waiting times. The response time of MSIT is 3.4ns for 32 data with 10-bit resolution in the simulation with 1.2V, $0.13{\mu}m$-process model parameters, which is much faster than its analog counterparts. It shows that digital MS circuits like MSIT can achieve higher speed as well as higher resolution than analog MS circuits.

• Mass Spectrometry Letters
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• v.12 no.4
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• pp.179-185
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• 2021

Collision-induced dissociation (CID) combined with electrospray ionization mass spectrometry (ESI-MS) was used to obtain structural information on rat islet amyloid polypeptide (rIAPP) monomers (M) and dimers (D) observed in the multiply charged state in the MS spectrum. MS/MS analysis indicated that the rIAPP monomers adopt distinct structures depending on the molecular ion charge state. Peptide bond dissociation between L₂₇ and P₂₈ was observed in the MS/MS spectra of rIAPP monomers, regardless of the monomer molecular ion charge state. MS/MS analysis of the dimers indicated that D⁵⁺ comprised M²⁺ and M³⁺ subunits, and that the peptide bond dissociation process between the L₂₇ and P₂₈ residues of the monomer subunit was also maintained. The observation of (M+ b₂₇)⁴⁺ and (M+ y₁₀)³⁺ fragment ions were deduced to originate from the two different D⁵⁺ complex geometries, the N-terminal and C-terminal interaction geometries, respectively. The fragmentation pattern of the [M_rIAPP + M_hIAPP]⁵⁺ MS/MS spectrum showed that the interaction occurred between the two N-terminal regions of M_rIAPP and M_hIAPP in the heterogeneous dimer (hetero-dimer) D⁵⁺ structure.

• Journal of Korean Ophthalmic Optics Society
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• v.21 no.1
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• pp.47-51
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• 2016

Purpose: The purpose of this study was to investigate the change of contrast sensitivity by prescribing tinted lenses and to provide the clinical manual. Methods: Contrast sensitivity was measured for twenty adults with normal vision while they wore yellow, orange and green tinted lenses. To measure contrast sensitivity, the 5 spatial frequencies (2, 4, 6, 8 and 10 cpd) were used for 33 ms and 233 ms, respectively. Results: The contrast sensitivity was overall higher with 233 ms than 33 ms (p<0.05). The peaks of contrast sensitivity with 33 ms and 233 ms were 1.75 log unit with the yellow lens and 1. 85 log unit without the color respectively. However, there was no significance between the yellow and orange tinted lens (p>0.64) Conclusions: Yellowish tinted lens that reduces chromatic aberration and the scattering is prescribed for the various purposes to improve visual functions. Before prescribing tinted lens, identifying characteristic of user and tinted lens for cut off wavelengths is recommended.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.6
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• pp.261-267
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• 2014

In this study, we manufactured melting temperature controllable modified surfur (MS) and studied the properties of sulfur modified cement concrete (SMC). We investigated the effects of sulfur and pyridine content on melting temperature of MS. The reaction is confirmed by measuring Raman spectrophotoscopy. The SMC was produced at Water (W)/Cement (C) = 45 wt%, Sand (S)/Aggregate (A) = 45 wt% and 5, 10, 15 and 20 % of MS on the basis of conventional portland cement, respectively. And then physical properties such as compressive strength, splitting tensile strength and permeability of SMC were measured. As MS added, permeability was decreased, while strength and spalling properties were improved. To confirm the safety of MS and SMC, pyrolyzed gas chromatography (P-GC) and gas hazard test were conducted. The results showed that MS and SMC were relatively safe at an elevated temperature.

• Analytical Science and Technology
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• v.20 no.5
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• pp.400-405
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• 2007

The comparative analysis of glycerin in cosmetic samples was carried out by LC/MS and $^1H$ NMR spectrometry. For the LC/MS analysis, aqueous solution was controlled in strong basic condition with sodium hydroxide, and benzoyl chloride was added to the solution for the derivatization of glycerin. The derivative was extracted using pentane and analyzed by the LC/MS. For the $^1H$ NMR analysis, sample was directly dissolved in $D_2O$ solvent without pretreatment. The quantitative analysis of glycerin was done by $^1H$ NMR ERETIC method. The analysis results of LC/MS and $^1H$ NMR showed that the calibration curves were a good linearity with $r^2=0.9991$ in the range of 0.1 to $10{\mu}g/mL$ and $r^2=1$ in the range of 25 to $500{\mu}g/mL$, respectively.

• Korean Circulation Journal
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• v.54 no.5
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• pp.270-287
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• 2024

Background and Objectives: Blood pressure (BP) measurement using an auscultatory sphygmomanometer is recommended for diagnosing hypertension in children. As mercury sphygmomanometers (MSs) are banned owing to environmental concerns, it is crucial to determine the accuracy of mercury-free sphygmomanometers to replace them. We analyzed the accuracy of these devices to guide the National Survey selection. Methods: BP was measured thrice each with MS, auscultatory device (AD), and oscillometric device (OD) in 104 participants aged 10-18 using the National Survey data. The difference in BP was defined as the difference between MS and other devices. The BP differences, correlations, and influencing factors were analyzed. The frequencies of hypertension were also compared. Results: Systolic BP (SBP) and diastolic BP (DBP) differences between MS and AD were 0.88±3.36 mmHg and 0.63±3.95 mmHg, and those between MS and OD were 0.43±5.83 mmHg and 4.57±6.89 mmHg, respectively. The absolute error of <10 mmHg for DBP between MS and OD was 76%. The concordance correlation coefficient between MS and AD was 0.94 for SBP and 0.90 for DBP, and 0.81 and 0.67, respectively for MS and OD. Arm circumference negatively correlated with BP differences except for SBP between the MS and OD. The frequency of hypertension was not different between MS and AD but was underestimated by OD. Conclusions: AD correlated well with MS, while OD did not, especially for DBP. The superiority of AD over OD suggests AD as a possible alternative for MS in the National Survey.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.4
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• pp.728-737
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• 2003

To evaluate microbial data and salivary measurements from clinically compatible, culture-based screening procedures employed with children younger than 36 months old. Plaque and stimulated saliva specimens were collected from 87 children. The pH of each saliva sample was measured before and after 0.94% lactic acid was added. Specimens were diluted and plated on selective media and non-selective media. Data collected were counts of mutans streptococci (MS) and lactobacilli (LB). In addition, total viable counts (TVC) of specimens, salivary pH and buffering capacity were also assessed. Each variable was compared to caries status of subjects. According to this study, the results were as followed: 1. Highly significant correlation with caries rates were found for counts of MS and LB. 2. The specific counts/ml saliva or plaque above which caries is predicted, or below which caries is not predicted were as follows: 1) Saliva MS; $10^5$ 2) Plaque MS; $2{\times}10^5$ 3) Saliva LB; $10^3$ 4) Plaque LB; $10^3$. 3. Salivary pH and buffering capacity versus caries status were not significant. 4. Microbial screening methods based on mutans streptococci had higher predictive values and odds ratios than methods for lactobacilli. 5. MS counts were clearly the best indicators of caries status in young children. This measurement can easily be obtained in a dental clinical setting both by conventional culture techniques, or commercial kits for MS recovery.

• Journal of Acupuncture Research
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• v.20 no.2
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• pp.1-10
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• 2003

Objective : It is limited to verify existence and a part of characteristic of MS(Meridian system) in modern MS hypothesis. Because it is that an object of scientific approach is to prove a structure of MS. Then according to DMMS, we will research on a subject of MSs rules. This is a paper on the investigation of DMMS in aspects of propriety and supplement. Results : DMMS is composed of organizational anatomy system, MS, signal system. This means that the contents of classic MS theory divide into three dimensions. It includes classic MS theory and explains modern MS hypothesis with DMMS. But is has two problems that one is the difference between the right side and the left in the same meridian and the other is a lack of dynamic idea(動態觀念). After apply this ti analysis system, it will be reasonable to DMMS. It indicates to use various ways of a science, especially, mathematics, system theory, information theory, control theory to supplement the DMMS. Conclusions : Although the scientific study of MS is stagnant, the approach of this DMMS will provide us with a new result of MS.

• Elastomers and Composites
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• v.51 no.1
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• pp.43-48
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• 2016

Multi-Surface (MS) treatment is a new technique of surface treatment to reduce the static friction factor on the surface of rubber. MS treatments include 4 methods which names are MS-V (UV-irradiation on the rubber surface), MS-M (doing the chemical reaction with double bond of rubber), MS-Q (dilution of rubber surface by silicone surfactant), and MS-P (coating and heating of rubber surface). The experiment and test of every MS-treatment had been carried out using acrylonitrile-butadiene rubber (NBR), ethylene-propylene-diene rubber (EPDM), and chlorosulphonated rubber (CSM) as rubber materials. It had introduced the steps of every MS-treatment process and the result of the properties test. From the research, it was found that the best method was MS-V treatment because it suited all the samples and the effect was obviously.