• Title/Summary/Keyword: critical coefficient

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Factors Influencing Post-traumatic Stress Disorder in Intensive Care Unit Nurses in Dedicated Hospitals for Coronavirus 19 (코로나바이러스 감염증(COVID-19) 전담병원 중환자실 간호사의 외상 후 스트레스 장애 영향 요인)

  • Jeong, Hyun Ok;Park, Hye-Ja
    • Journal of East-West Nursing Research
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    • v.28 no.2
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    • pp.170-178
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    • 2022
  • Purpose: This study aimed to identify the factors influencing post-traumatic stress disorder in intensive care unit nurses in dedicated hospitals for coronavirus disease of 2019 (COVID-19) during the peak of the outbreak. Methods: This study used a cross-sectional correlational design. A total of 100 participants completed questionnaires comprising the Impact of Event Scale-Revised (IES-R), coping strategy indicator, social support, and post-traumatic growth. Post-traumatic stress disorder was classified as normal, mild risk, and high risk. Data were analyzed using 𝛘2 test, Fisher's exact test, Kruskal-Wallis test with multiple comparison analysis, Pearson correlation coefficient, and multinominal logistic regression analysis. Results: Fifty seven nurses (57.0%) had a high risk of post-traumatic stress. Higher levels of post traumatic stress were associated with higher levels of social support seeking, and higher levels of avoidance, and lower levels of social support from supervisors. Higher post traumatic growth was correlated with higher social support for seeking coping, and problem solving coping strategies, and social support from supervisors and colleagues. Post-traumatic stress risk was associated with social support seeking and supervisors' social support. In addition, a higher risk of post-traumatic stress was related to COVID-19 work duration and supervisors' social support. Conclusion: Supportive programs, including increasing social support and building coping skills, may be suggested to safeguard the mental health of critical care nurses during the pandemic.

A Sensitive, Efficient, and Cost-Effective Method to Determine Rotigotine in Rat Plasma Using Liquid-Liquid Extraction (LLE) and LC-MRM

  • Kim, Ji Seong;Jang, Yong Jin;Kim, Jin Hee;Kim, Jin Hwan;Seo, Jae Hee;Park, Il-Ho;Kang, Myung Joo;Choi, Yong Seok
    • Mass Spectrometry Letters
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    • v.13 no.4
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    • pp.146-151
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    • 2022
  • Rotigotine (RTG) is a non-ergot dopamine agonist used to manage the early stage of Parkinson's disease (PD) as transdermal patch. However, the poor medication compliance of PD patients and skin issues related with repeated applications of RTG patches lead to the search for alternative formulations and it also requires appropriate analytical methods for their in vivo evaluation. Thus, here, a sensitive, efficient, and cost-effective method to determine RTG in rat plasma using liquid-liquid extraction (LLE) and multiple reaction monitoring was developed. The use of 20 µL of rat plasma for sample treatment, 8-OH-DPAT as the internal standard, and methyl tert-butyl ether as the LLE solvent in the present method gives it advantages over previous methods for the analysis of RTG in biological samples. The good analytical performance of the developed method was confirmed in specificity, linearity (the coefficient of determination ≥0.999 within 0.1-100 ng/mL), sensitivity (the lower limit of quantitation at 0.1 ng/mL), accuracy (81.00-115.05%), precision (≤10.75%), and recovery (81.00-104.48%) by following the FDA guidelines. Finally, the applicability test of the validated method to the in vivo evaluation of a RTG formulation showed that the present method is the only method which can be accurately applied to that longer than 24 hours, critical for the development of formulations with reduced dosing frequencies. Therefore, the present method could contribute to the development of new RTG formulations helpful to people suffering from PD.

Correlation Between Knee Muscle Strength and Maximal Cycling Speed Measured Using 3D Depth Camera in Virtual Reality Environment

  • Kim, Ye Jin;Jeon, Hye-seon;Park, Joo-hee;Moon, Gyeong-Ah;Wang, Yixin
    • Physical Therapy Korea
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    • v.29 no.4
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    • pp.262-268
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    • 2022
  • Background: Virtual reality (VR) programs based on motion capture camera are the most convenient and cost-effective approaches for remote rehabilitation. Assessment of physical function is critical for providing optimal VR rehabilitation training; however, direct muscle strength measurement using camera-based kinematic data is impracticable. Therefore, it is necessary to develop a method to indirectly estimate the muscle strength of users from the value obtained using a motion capture camera. Objects: The purpose of this study was to determine whether the pedaling speed converted using the VR engine from the captured foot position data in the VR environment can be used as an indirect way to evaluate knee muscle strength, and to investigate the validity and reliability of a camera-based VR program. Methods: Thirty healthy adults were included in this study. Each subject performed a 15-second maximum pedaling test in the VR and built-in speedometer modes. In the VR speedometer mode, a motion capture camera was used to detect the position of the ankle joints and automatically calculate the pedaling speed. An isokinetic dynamometer was used to assess the isometric and isokinetic peak torques of knee flexion and extension. Results: The pedaling speeds in VR and built-in speedometer modes revealed a significantly high positive correlation (r = 0.922). In addition, the intra-rater reliability of the pedaling speed in the VR speedometer mode was good (ICC [intraclass correlation coefficient] = 0.685). The results of the Pearson correlation analysis revealed a significant moderate positive correlation between the pedaling speed of the VR speedometer and the peak torque of knee isokinetic flexion (r = 0.639) and extension (r = 0.598). Conclusion: This study suggests the potential benefits of measuring the maximum pedaling speed using 3D depth camera in a VR environment as an indirect assessment of muscle strength. However, technological improvements must be followed to obtain more accurate estimation of muscle strength from the VR cycling test.

A Study on the Demand Prediction Model for Repair Parts of Automotive After-sales Service Center Using LSTM Artificial Neural Network (LSTM 인공신경망을 이용한 자동차 A/S센터 수리 부품 수요 예측 모델 연구)

  • Jung, Dong Kun;Park, Young Sik
    • The Journal of Information Systems
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    • v.31 no.3
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    • pp.197-220
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    • 2022
  • Purpose The purpose of this study is to identifies the demand pattern categorization of repair parts of Automotive After-sales Service(A/S) and proposes a demand prediction model for Auto repair parts using Long Short-Term Memory (LSTM) of artificial neural networks (ANN). The optimal parts inventory quantity prediction model is implemented by applying daily, weekly, and monthly the parts demand data to the LSTM model for the Lumpy demand which is irregularly in a specific period among repair parts of the Automotive A/S service. Design/methodology/approach This study classified the four demand pattern categorization with 2 years demand time-series data of repair parts according to the Average demand interval(ADI) and coefficient of variation (CV2) of demand size. Of the 16,295 parts in the A/S service shop studied, 96.5% had a Lumpy demand pattern that large quantities occurred at a specific period. lumpy demand pattern's repair parts in the last three years is predicted by applying them to the LSTM for daily, weekly, and monthly time-series data. as the model prediction performance evaluation index, MAPE, RMSE, and RMSLE that can measure the error between the predicted value and the actual value were used. Findings As a result of this study, Daily time-series data were excellently predicted as indicators with the lowest MAPE, RMSE, and RMSLE values, followed by Weekly and Monthly time-series data. This is due to the decrease in training data for Weekly and Monthly. even if the demand period is extended to get the training data, the prediction performance is still low due to the discontinuation of current vehicle models and the use of alternative parts that they are contributed to no more demand. Therefore, sufficient training data is important, but the selection of the prediction demand period is also a critical factor.

A Brief Review of Some Challenging Issues in Textured Piezoceramics via Templated Grain Growth Method

  • Hye-Lim Yu;Nu-Ri Ko;Woo-Jin Choi;Temesgen Tadeyos Zate;Wook Jo
    • Journal of Sensor Science and Technology
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    • v.32 no.1
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    • pp.10-15
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    • 2023
  • It is well known that polycrystalline ceramics fabricated via the templated grain growth method along a desired crystallographic direction, generally along [001], exhibits enhanced piezoelectric response. Generally, the piezoelectric properties of textured ceramics depend on the degree of texture, as piezoelectric properties peak in single crystals. Therefore, understanding the relationship between the degree of texture and piezoelectric properties is fundamental. Here, we present state-of-the-art textured piezoceramics by focusing on critical issues such as the quality of templates used for texturing and proper evaluation of the degree of texture analysis. The relationship between the degree of texture and its impact on the properties of textured materials is exclusively defined by the Lotgering factor (L.F.) calculated from the X-ray diffraction profiles. Additionally, we show that L.F. is not a suitable indicator of the degree of texture, contrary to previous interpretations. This statement was further supported by the fact that the true degree of texture can be better quantified by the multiples of random distribution. This argument was justified by comparing the quantitative values of the degree of texture obtained from both methods to those of the piezoelectric charge coefficient of textured and random ceramics.

Estimating the unconfined compression strength of low plastic clayey soils using gene-expression programming

  • Muhammad Naqeeb Nawaz;Song-Hun Chong;Muhammad Muneeb Nawaz;Safeer Haider;Waqas Hassan;Jin-Seop Kim
    • Geomechanics and Engineering
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    • v.33 no.1
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    • pp.1-9
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    • 2023
  • The unconfined compression strength (UCS) of soils is commonly used either before or during the construction of geo-structures. In the pre-design stage, UCS as a mechanical property is obtained through a laboratory test that requires cumbersome procedures and high costs from in-situ sampling and sample preparation. As an alternative way, the empirical model established from limited testing cases is used to economically estimate the UCS. However, many parameters affecting the 1D soil compression response hinder employing the traditional statistical analysis. In this study, gene expression programming (GEP) is adopted to develop a prediction model of UCS with common affecting soil properties. A total of 79 undisturbed soil samples are collected, of which 54 samples are utilized for the generation of a predictive model and 25 samples are used to validate the proposed model. Experimental studies are conducted to measure the unconfined compression strength and basic soil index properties. A performance assessment of the prediction model is carried out using statistical checks including the correlation coefficient (R), the root mean square error (RMSE), the mean absolute error (MAE), the relatively squared error (RSE), and external criteria checks. The prediction model has achieved excellent accuracy with values of R, RMSE, MAE, and RSE of 0.98, 10.01, 7.94, and 0.03, respectively for the training data and 0.92, 19.82, 14.56, and 0.15, respectively for the testing data. From the sensitivity analysis and parametric study, the liquid limit and fine content are found to be the most sensitive parameters whereas the sand content is the least critical parameter.

Residue Monitoring and Dietary Risk Evaluation of Fungicide Propiconazole in Leafy Vegetables under Greenhouse Conditions

  • Lawal Abdulkareem;Ji-Eun Oh;Se-Yeon Kwak;Sang-Hyeob Lee;Jae-Won Choi;Aniruddha Sarker;Kee Sung Kyung;Tae Hwa Kim;Jang-Eok Kim
    • Korean Journal of Environmental Agriculture
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    • v.42 no.3
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    • pp.193-202
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    • 2023
  • Residue monitoring of propiconazole (PCZ) in cabbage, shallot, and spinach was conducted under multi-trial greenhouse conditions. This study aimed to understand the fate of the applied fungicide in these vegetables. Furthermore, the associated health risk of PCZ in leafy vegetables was assessed through dietary risk assessment. Commercially available PCZ (22% suspension concentrate) was administered thrice according to the OECD fungicide application interval guideline. The plant samples were extracted using a slightly modified QuEChERS technique and analyzed using gas chromatography-tandem mass spectrometry. The average PCZ recovery was between 84.5% and 117.6%, with a <5% coefficient of variance. The dissipation of PCZ residue in cabbage, shallot, and spinach after 14 days was 96%, 90%, and 99%, respectively, with half-lives of <5 days. Meanwhile, dietary risk assessments of PCZ residues in the studied vegetables using the risk quotient (RQ) were significant < 100 (RQ < 100). Thus, the population groups considered in this study were not at substantial risk from consuming leafy vegetables sprayed with PCZ following critical, good agricultural practices.

Association between Taql polymorphism of vitamin D receptor gene and vertical growth of the mandible: A cross-sectional study

  • Baris Can Telatar;Gul Yildiz Telatar;Faruk Saydam
    • The korean journal of orthodontics
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    • v.53 no.5
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    • pp.336-342
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    • 2023
  • Objective: To determine whether the gonial angle on digital panoramic radiographs is associated with vitamin D receptor (VDR) Taql polymorphism. Methods: Genomic DNA samples were collected from the buccal mucosa of patients aged 26-43 years. TaqMan assay for single nucleotide polymorphism genotyping was used to detect the genotype of Taql polymorphism. The gonial angle was measured bilaterally on panoramic radiography. The normal gonial angle was fixed as 121.8°, and it represented the cutoff value for the high gonial angle (HGA) and low gonial angle (LGA) groups. Various genetic models were analyzed, namely dominant (homozygous [AA] vs. heterozygous [AG] + polymorphic [GG]), recessive (AA + AG vs. GG), and additive (AA + GG vs. AG), using the chi-squared test. Results: The reliability of the gonial angle measurement was analyzed using a random sample (26%) of the tests, with the intra-examiner correlation showing an intra-class correlation coefficient of 0.99. The frequencies of the AA, AG, and GG genotypes of rs731236 polymorphism were 40.5%, 41.9%, and 17.6% in the HGA group and 21.8%, 51.0%, and 27.2% in the LGA group, respectively (P = 0.042). A statistically significant difference was observed in the allele frequencies between the two groups (P = 0.011). Moreover, a significant correlation was observed in the dominant genetic model. Conclusions: Taql polymorphism in the VDR gene plays a critical role in the vertical growth of the mandible and decreased gonial angle.

Measuring the Impact of Supply Network Topology on the Material Delivery Robustness in Construction Projects

  • Heo, Chan;Ahn, Changbum;Yoon, Sungboo;Jung, Minhyeok;Park, Moonseo
    • International conference on construction engineering and project management
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    • 2022.06a
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    • pp.269-276
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    • 2022
  • The robustness of a supply chain (i.e., the ability to cope with external and internal disruptions and disturbances) becomes more critical in ensuring the success of a construction project because the supply chain of today's construction project includes more and diverse suppliers. Previous studies indicate that topological features of the supply chain critically affect its robustness, but there is still a great challenge in characterizing and quantifying the impact of network topological features on its robustness. In this context, this study aims to identify network measures that characterize topological features of the supply chain and evaluate their impact on the robustness of the supply chain. Network centrality measures that are commonly used in assessing topological features in social network analysis are identified. Their validity in capturing the impact on the robustness of the supply chain was evaluated through an experiment using randomly generated networks and their simulations. Among those network centrality measures, the PageRank centrality and its standard deviation are found to have the strongest association with the robustness of the network, with a positive correlation coefficient of 0.6 at the node level and 0.74 at the network level. The findings in this study allows for the evaluation of the supply chain network's robustness based only on its topological design, thereby enabling practitioners to better design a robust supply chain and easily identify vulnerable links in their supply chains.

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Residual Characteristics of Lufenuron in Crown Daisy and Chamnamul for Establishing Pre-Harvest Residue Limit (쑥갓 및 참나물 중 Lufenuron의 생산단계 잔류허용기준 설정을 위한 잔류 특성 연구)

  • A-Yeon Oh;Sun-Woo Ban;Hee-Ra Chang
    • Korean Journal of Environmental Agriculture
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    • v.42 no.1
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    • pp.21-27
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    • 2023
  • Pre-harvest residue limits (PHRLs) have been proposed as criteria for a proactive role to exceed the maximum residue limit (MRL) of pesticides in agricultural products at harvest. However, PHRL numbers are significantly less than those of established MRLs. This study was performed to determine the dissipation constants and residual concentrations of lufenuron after application on crown daisy and chamnamul under green house conditions. Two residue field trials for each crown daisy and chamnamul were selected to consider a different geographical site at least 20 km far from one another. The pesticide was treated according to critical GAP. After samples were sprayed with lufenuron, they were collected at 0, 1, 3, 5, 7, 10, and 14 days and analyzed using HPLC-DAD. The mean recoveries of crown daisy and chamnamul were within the range of 70-120% with below 20% coefficient variation, which is within the acceptable limits specified by the manual of pre-harvest residue study for pesticides (MFDS, 2014). The biological half-lives in field I and field II were 7.0 and 4.6 days for crown daisy and 2.7 and 2.8 days for chamnamul, respectively. The lower bounds of 95% confidence intervals of dissipation rate constants of lufenuron in crown daisy were determined to be 0.0692 and 0.1298 for field I and field II, respectively, and in chamnamul were 0.2067 for both field I and field II. After applying lufenuron 5% EC, the lufenuron residues on crown daisy and chamnamul at the pre-harvest intervals (14 days for crown daisy and 7 days for chamnamul) were below the safe levels. The dissipation rates of lufenuron in crown daisy and chamnamul were evaluated for similarities with leafy vegetables based on a 95% confidence interval.