• FOCUS: LIFE SCIENCE
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• no.1
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• pp.8.1-8.3
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• 2024

Ultra-high performance liquid chromatography (UHPLC) systems are integral to modern analytical laboratories, necessitating careful maintenance and operation protocols to ensure optimal performance. This document provides comprehensive guidelines for the proper shutdown and reactivation of UHPLC systems to prevent damage and maintain operational efficiency. • Shutdown: Remove the column and replace it with a union to avoid blockages. Flush the system with a compatible solvent mix, clean mobile phase reservoirs to prevent microbial growth, flush the pump with storage solvent, and clean the autosampler, including the needle and injection port. • Reactivation: Inspect the system for wear or damage, gradually reintroduce mobile phases starting with a weak solvent, reinstall the column securely, and perform system checks on baseline stability, pressure consistency, and detector performance. By adhering to these guidelines, laboratories can ensure the longevity and reliability of their UHPLC systems, maintaining high analytical performance and minimizing downtime. These procedures help prevent common issues such as blockages, contamination, and component wear, thereby supporting efficient and accurate analytical operations.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4415-4419
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• 2013

Background: Measuring effects of cancer on family caregivers is important to develop methods which can improve their quality of life (QOL). Nevertheless, up to now, only a few tools have been developed to be used in this group. Among those, the Caregiver Quality of Life Index-Cancer Scale (CQOLC) has met minimum psychometric criteria in different populations in spite of conflicting results. The present study was conducted to evaluate reliability and validity of CQOLC among Turkish cancer family caregivers. Materials and Methods: The CQOLC was administered to 120 caregivers, along with Beck Depression Inventory (BDI), Medical Outcomes Study MOS 36- Item Short Form Health Survey (SF-36), State-Trait Anxiety Inventory (STAI), and Multidimensional Scale of Perceived Social Support (MSPSS). Internal consistency and test-retest stability were used to investigate reliability. Construct validity was examined by using known group method, convergent, and divergent validity. For the known group method, we hypothesized that CQOLC scores would differ between depressed and non-depressed subjects. We investigated convergent validity by correlating scores for CQOLC with scores for other similar measures including SF-36 and STAI. The MSPSS was completed at the same time as CQOLC to provide divergent validity. Results: The values for internal consistency and test-retest correlation were 0.88 and 0.96, respectively. The CQOLC discriminated those who were depressed from those who were not. Convergent validity supported strong correlations between CQOLC scores and two main component scores (PCS, MCS) in SF-36 although there was a weak correlation between CQOLC and STAI scores. Regarding divergent validity, the correlation between CQOLC and MSPSS was in the low range, as expected. Conclusions: The Turkish CQOLC is a reliable and valid tool and it can be utilized to determine QOL of family caregivers.

• Journal of Preventive Medicine and Public Health
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• v.53 no.3
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• pp.180-188
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• 2020

Objectives: The Short Form 36 (SF-36) questionnaire is increasingly being used to measure health-related quality of life (HRQoL) in Indonesia. However, evidence that it is valid for use in Indonesian adults is lacking. This study assessed the validity and reliability of the SF-36 in Indonesian middle-aged and older adults. Methods: Adults aged 46-81 years (n=206) in Yogyakarta, Indonesia completed the SF-36, another measure of HRQoL (the EuroQoL visual analogue scale [EQ-VAS]), and measures assessing their demographic characteristics. Fifty-four percent (n=121) completed the SF-36 measure again 1 week later. Confirmatory factor analysis was conducted to confirm the factor structure of the SF-36. Internal consistency reliability was estimated using Cronbach's alpha, and test-retest reliability was assessed using intraclass correlations. Convergent and discriminant validity were assessed by computing correlations among SF-36 subscales, between subscales and the 2 component scores, and between component scores and EQ-VAS scores. Results: Most scaling assumptions were met. The hypothetical factor structure fit the data poorly (root mean square error of approximation [RMSEA]=0.108) and modification was required for a good fit (RMSEA=0.060). Scores on all subscales demonstrated acceptable internal consistency (α>0.70) and test-retest reliability (r>0.70). Divergent validity was supported by weak to moderate interscale correlations (r=0.19 to 0.64). As expected, the 2 summary scores were moderately to strongly correlated with the EQ-VAS (r>0.60). Conclusions: The findings adequately support the use of SF-36 in Indonesian middle-aged and older adults, although the optimal algorithm for computing component scores in Indonesia warrants further investigation.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.826-831
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• 1989

The rheological properties of concentrated Kochujang (Korean red pepper paste)-water suspensions were investigated. The rheological behavior of Kochujang-water suspension was illustrated by Herschel-Bulkley equation. All Kochujang-water suspensions with 12.5-100% of water addition showed pseudoplasticity in yield stress at the shear rate range of $0.25-179.20sec^{-1}$., but at the shear rate above $5.16 sec^{-1}$, more shear thinning behavior was observed with increasing shear rate. Also, pseudoplasticity of the suspension became weak by increasing water addition and decreasing temperature, The temperature dependence of consistency index on Kochujang-suspension was very low and the values of consistency index was lowered by increasing solid contents, but as heating, the values of that was increased. It was suggested that the main components responsible for rheological behavior of the suspensions at high temperature might be undigested starch or protein in Kochujang. Also, the changes of rheological behavior with vinegar addtion was only due to dilution effect.

• Journal of Korean Biological Nursing Science
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• v.20 no.1
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• pp.11-19
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• 2018

Purpose: The purposes of this study were to perform items analysis using the classical test theory (CTT) and the item response theory (IRT), and to establish the validity and reliability of the Korean version of pressure ulcer prevention knowledge. Methods: The 26-item pressure ulcer prevention knowledge instrument was translated into Korean, and the item analysis of the 22 items having an adequate content validity index (CVI), was conducted. A total of 240 registered nurses in 2 university hospitals completed the questionnaire. Each item was analyzed applying CTT and IRT according to 2-parameter logistic model. Response alternatives quality, item difficulty and item discrimination were evaluated. For testing validity and reliability, Pearson correlation coefficient and Kuder Richardson-20 (KR-20) were used. Results: Scale CVI was .90 (Item-CVI range= .75-1.00). The total correct answer rate for this study population was relatively low as 52.5%. The quality of response alternatives was found to be relatively good (range= .02-.83). The item difficulty of the questions ranged form .10 to .86 according to CTT and -12.19 to 29.92 according to the IRT. This instrument had 12-low, 2-medium and 8-high item difficulty applying IRT. The values for the item discrimination ranged .04-.57 applying CTT and .00-1.47 applying IRT. And overall internal consistency (KR-20) was .62 and stability (test-retest) was .82. Conclusion: The instrument had relatively weak construct validity, item discrimination according to the IRT. Therefore, the cautious usage of a Korean version of this instrument would be recommended for discrimination because there are so many attractive response alternatives and low internal consistency.

• Atmosphere
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• v.17 no.1
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• pp.69-86
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• 2007

The characteristics of the dual-Doppler wind retrieval method based on a three dimensional variational (3DVAR) conception were investigated from the following four points of view; the sensitivity of the number of iteration, the effect of the weak constraint term, the effect of the smoothness term, and the sensitivity of the error mixing ratio of the radial velocities. In the experiment, the radial velocities relative to the Gosan and Jindo radar sites of the Korea Meteorological Administration (KMA) were calculated from the forecasting of the WRF (Weather Research and Forecast; Skamarock, 2004) model at 1330 UTC 30 June 2006, which is the one and half hour forecast from the initial time, 1200 UTC on that day. The results showed that the retrieval performance of the horizontal wind field was robust, but that of the vertical wind was sensitive to the external conditions, such as iteration number and the on/off of the weak constraint term. The sensitivity of error mixing ratio was so large that even the horizontal wind retrieval efficiency was reduced a lot. But the sensitivity of the smooth term was not so large. When we applied this method to the real mesoscale convective system (MCS) between the Gosan and Jindo radar pair at 1430 UTC 30 June 2006, the wind structure of the convective cells in the MCS was consistently retrieved relative to the reflectivity factor structure. By comparing the vertical wind structure of this case with that of 10 minutes after, 1440 UTC 30 June 2006, we got the physical consistency of our method.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.125.1-125.1
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• 2012

The wave number 4 (wave-4) and wave number 3 (wave-3) longitudinal structures in the thermospheric neutral mass density are understood as tidal structures driven by diurnal eastward-propagating zonal wave number 3 (DE3) and wave number 2 (DE2) tides, respectively. However, those structures have been identified using data from limited time periods, and the consistency and recurrence of those structures have not yet been examined using long-term observation data. We examine the persistence of those structures by analyzing the neutral mass density data for the years 2001-2008 taken by the CHAllenging Minisatellite Payload (CHAMP) satellite. During years of low solar activity, the amplitude of the wave-4 structure is pronounced during August and September, and the wave-4 phase shows a consistent eastward phase progression of $90^{\circ}$ within 24 h local time in different months and years. During years of high solar activity, the wave-4 amplitude is small and does not show a distinctive annual pattern, but the tendency of the eastward phase shift at a rate of $90^{\circ}$/24 h exists. Thus the DE3 signature in the wave-4 structure is considered as a persistent feature. The wave-3 structure is a weak feature in most months and years. The amplitude and phase of the wave-3 structure do not show a notable solar cycle dependence. Among the contributing tidal modes to the wave-3 structure, the DE2 amplitude is most pronounced. This result may suggest that the DE2 signature, although it is a weak signature, is a perceivable persistent feature in the thermosphere.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.1115-1118
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• 2005

With the development of the internet technology, The on-line conference system have been producted. Now, the on-line conference system is developing for using pattern recognition system and voice recognition system. Comparing with the off-line conference, the on-line conference is excellent in free from distance limitation. But, the on-line meetings have unavoidable weak points. it is the same as the off-line conference that when the conference goes on, the content orthopedic and the content consistency is weak. So the conference members can not seize the conference flow. Therefore, in this paper, we introduce the ontology concept. Design a new architecture using ontology mining technique for making the conference content and conference knowledge ontological. Then in order to inspection the new architecture, We design and implementation the new conference management system based knowledge.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.1
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• pp.1-6
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• 2003

It has been suggested that people who suffer from impaired masticatory function may adapt food consistency to their oral status (which may lead to deficient nutrient intake) or rely on the digestive system to compensate for the lack of oral preparation of food (which may increase the likelihood of digestive diseases and decrease gut absorption). Masticatory deficiency thus may be detrimental to health. This article reviews evidence of the effects of masticatory deficiency on nutrition. The selection of relevant literature was based on Medline queries using the following key words: mastication, nutrition, digestion, diet, and disease risk. Earlier work not listed in Medline but related to the subject also was reviewed. Only publications available in English were selected for inclusion. It is difficult to draw conclusions from many of the reviewed studies due to issues related to study design, confounding variables, and the subjective nature of the measurements. In particular, data supporting a link between masticatory function and deficient dietary intake often are based on relatively weak correlations and cannot confer a causal relationship.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.8 s.197
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• pp.58-66
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• 2007

In order to improve the recyclability and to reduce the recycling cost and time, the disassembly technology should be systemized because the worn out products can be reused or recycled after disassembly processes. This paper attempts to propose the integrated CATIA-based DfD (Design for Disassembly) support system to promote the disassemblability of products. The system is composed of two modules; evaluation of disassemblability, generation of DfD alternatives. The disassemblability of current vehicle is evaluated to identify the weak point in terms of disassembly using the DELMIA and developed evaluation system. Furthermore a new expert system is developed to propose the optimal redesign rule and principle for generating the DfD alternatives. In order to generate the DfD alternatives, a CATIA-based design support system is implemented. The system can provide quick results and ensure consistency and completeness of the redesign alternatives.