• Title/Summary/Keyword: Psi ($\Psi$)

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Predictors of discogenic pain in magnetic resonance imaging: a retrospective study of provocative discography performed by posterolateral approach

  • Jain, Anuj;Jain, Suruchi;Barasker, Swapnil Kumar;Agrawal, Amit
    • The Korean Journal of Pain
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    • v.34 no.4
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    • pp.447-453
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    • 2021
  • Background: Provocative discography (PD) is a test that is useful in diagnosing discogenic pain (DP). In this study, to diagnose DP, we used a posterolateral approach of needle placement and followed pressure criteria laid down by the Spine Intervention Society. The aim was to identify the correlation between magnetic resonance imaging (MRI) findings (desiccation, high intensity zone and change in shape and size of the disc) and the results of PD. Methods: Records of 50 patients who underwent PD for DP were analyzed. A total of 109 PDs were performed, with 54 suspect and 55 control discs. Alternate pain generators were ruled out. Results: A total of 35 suspect discs were positive on PD. The mean disc pressure in the suspect disc was 31.9 ± 7.9 psi (range, 15-44). Of the 50 patients who underwent PD, 35 had positive MRI findings. A significant positive correlation was found only between disc desiccation and discography result (r = 0.6, P < 0.001). Logistic regression analysis revealed that only desiccation successfully predicted the result of discography (OR = 26.5, P < 0.001); a high intensity zone and a disc protrusion/extrusion had an OR 2.3 and 1.24, respectively. Disc desiccation of Pfirmann grade 3 or more had a sensitivity and specificity of 0.93 and 0.64 respectively in identifying painful discs; the positive likelihood ratio was 2.58 while the negative likelihood ratio was 0.11. Conclusions: In patients with DP, disc desiccation is the most useful MRI feature that predicts a painful disc on PD.

Effects of Particle Size and High Pressure Process on the Extraction Yield of Oil Compounds from Soybean Powder Using Hexane and Supercritical Fluid (입자 크기와 초고압 처리에 따른 유기용매와 초임계 유체 추출법에서의 대두유 추출수율의 변화)

  • Yoon, Won-Byong
    • Food Engineering Progress
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    • v.15 no.3
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    • pp.203-208
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    • 2011
  • Effects of particle size and high pressure processing on the extraction rate of oil compounds from soybean powder were evaluated by Soxhlet method using hexane and supercritical fluid extraction (SFE) using $CO_{2}$. SFE was carried out at 4,000 psi and $50^{\circ}C$ for 4 hr. The mean particle sizes were varied from 26.7 to 862.0 ${\mu}m$ by controlling milling time. Saturation solubility increased as the particle size decreased. At large particle size, high pressure processing (HPP) showed higher extraction yield in both hexane extraction and SFE, but, as the particle size decreased, the HPP was irrelevant to the extraction yield in SFE. The higher extraction rate obtained from the smaller particle size. The scanning electronic microscopy of soybean powder treated by HPP showed pores on the surface of the particle. The higher extraction rate and yield from HPP treatment might be due to the less internal resistance of transferring the solvent and miscellar in the solid matrix by collapsing of tissues.

Performance Evaluation of Deep Neural Network (DNN) Based on HRV Parameters for Judgment of Risk Factors for Coronary Artery Disease (관상동맥질환 위험인자 유무 판단을 위한 심박변이도 매개변수 기반 심층 신경망의 성능 평가)

  • Park, Sung Jun;Choi, Seung Yeon;Kim, Young Mo
    • Journal of Biomedical Engineering Research
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    • v.40 no.2
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    • pp.62-67
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    • 2019
  • The purpose of this study was to evaluate the performance of deep neural network model in order to determine whether there is a risk factor for coronary artery disease based on the cardiac variation parameter. The study used unidentifiable 297 data to evaluate the performance of the model. Input data consists of heart rate parameters, which are SDNN (standard deviation of the N-N intervals), PSI (physical stress index), TP (total power), VLF (very low frequency), LF (low frequency), HF (high frequency), RMSSD (root mean square of successive difference) APEN (approximate entropy) and SRD (successive R-R interval difference), the age group and sex. Output data are divided into normal and patient groups, and the patient group consists of those diagnosed with diabetes, high blood pressure, and hyperlipidemia among the various risk factors that can cause coronary artery disease. Based on this, a binary classification model was applied using Deep Neural Network of deep learning techniques to classify normal and patient groups efficiently. To evaluate the effectiveness of the model used in this study, Kernel SVM (support vector machine), one of the classification models in machine learning, was compared and evaluated using same data. The results showed that the accuracy of the proposed deep neural network was train set 91.79% and test set 85.56% and the specificity was 87.04% and the sensitivity was 83.33% from the point of diagnosis. These results suggest that deep learning is more efficient when classifying these medical data because the train set accuracy in the deep neural network was 7.73% higher than the comparative model Kernel SVM.

Ginsenoside compound K protects human umbilical vein endothelial cells against oxidized low-density lipoprotein-induced injury via inhibition of nuclear factor-κB, p38, and JNK MAPK pathways

  • Lu, Shan;Luo, Yun;Zhou, Ping;Yang, Ke;Sun, Guibo;Sun, Xiaobo
    • Journal of Ginseng Research
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    • v.43 no.1
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    • pp.95-104
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    • 2019
  • Background: Oxidized low-density lipoprotein (ox-LDL) causes vascular endothelial cell inflammatory response and apoptosis and plays an important role in the development and progression of atherosclerosis. Ginsenoside compound K (CK), a metabolite produced by the hydrolysis of ginsenoside Rb1, possesses strong anti-inflammatory effects. However, whether or not CK protects ox-LDL-damaged endothelial cells and the potential mechanisms have not been elucidated. Methods: In our study, cell viability was tested using a 3-(4, 5-dimethylthiazol-2yl-)-2,5-diphenyl tetrazolium bromide (MTT) assay. Expression levels of interleukin-6, monocyte chemoattractant protein-1, tumor necrosis factor-${\alpha}$, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 were determined by enzyme-linked immunosorbent assay and Western blotting. Mitochondrial membrane potential (${\Delta}{\Psi}m$) was detected using JC-1. The cell apoptotic percentage was measured by the Annexin V/ propidium iodide (PI) assay, lactate dehydrogenase, and caspase-3 expression. Apoptosis-related proteins, nuclear factor $(NF)-{\kappa}B$, and mitogen-activated protein kinases (MAPK) signaling pathways protein expression were quantified by Western blotting. Results: Our results demonstrated that CK could ameliorate ox-LDL-induced human umbilical vein endothelial cells (HUVECs) inflammation and apoptosis, $NF-{\kappa}B$ nuclear translocation, and the phosphorylation of p38 and c-Jun N-terminal kinase (JNK). Moreover, anisomycin, an activator of p38 and JNK, significantly abolished the anti-apoptotic effects of CK. Conclusion: These results demonstrate that CK prevents ox-LDL-induced HUVECs inflammation and apoptosis through inhibiting the $NF-{\kappa}B$, p38, and JNK MAPK signaling pathways. Thus, CK is a candidate drug for atherosclerosis treatment.

Neuroprotective mechanisms of dieckol against glutamate toxicity through reactive oxygen species scavenging and nuclear factor-like 2/heme oxygenase-1 pathway

  • Cui, Yanji;Amarsanaa, Khulan;Lee, Ji Hyung;Rhim, Jong-Kook;Kwon, Jung Mi;Kim, Seong-Ho;Park, Joo Min;Jung, Sung-Cherl;Eun, Su-Yong
    • The Korean Journal of Physiology and Pharmacology
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    • v.23 no.2
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    • pp.121-130
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    • 2019
  • Glutamate toxicity-mediated mitochondrial dysfunction and neuronal cell death are involved in the pathogenesis of several neurodegenerative diseases as well as acute brain ischemia/stroke. In this study, we investigated the neuroprotective mechanism of dieckol (DEK), one of the phlorotannins isolated from the marine brown alga Ecklonia cava, against glutamate toxicity. Primary cortical neurons ($100{\mu}M$, 24 h) and HT22 neurons (5 mM, 12 h) were stimulated with glutamate to induce glutamate toxic condition. The results demonstrated that DEK treatment significantly increased cell viability in a dose-dependent manner ($1-50{\mu}M$) and recovered morphological deterioration in glutamate-stimulated neurons. In addition, DEK strongly attenuated intracellular reactive oxygen species (ROS) levels, mitochondrial overload of $Ca^{2+}$ and ROS, mitochondrial membrane potential (${\Delta}{\Psi}_m$) disruption, adenine triphosphate depletion. DEK showed free radical scavenging activity in the cell-free system. Furthermore, DEK enhanced protein expression of heme oxygenase-1 (HO-1), an important anti-oxidant enzyme, via the nuclear translocation of nuclear factor-like 2 (Nrf2). Taken together, we conclude that DEK exerts neuroprotective activities against glutamate toxicity through its direct free radical scavenging property and the Nrf-2/HO-1 pathway activation.

A Preliminary Study on the Change of Intraday Heart Rate Variability and Related Factors in Healthy People (건강인의 일중 심박변이도 변화 및 관련인자에 대한 예비연구)

  • Noh, Eun-Ji;Choi, Su-Ji;Kim, Deok-Ho;Choi, Yun-Seok;Kim, Dong-Il
    • The Journal of Korean Medicine
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    • v.42 no.2
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    • pp.50-61
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    • 2021
  • Objectives: The object of this study was to examine whether there was a significant difference between morning and afternoon in heart rate variability(HRV) in healthy Korean adults. In addition, the correlation between the characteristics of the subjects and the test results was analyzed. Methods: From January 8, 2021 to January 29, 2021, twenty healthy subjects received short-term HRV test once in the morning(6:00~12:00) and twice in the afternoon(12:00~18:00). We used IBM SPSS Statistics 27 to test for statistical significance. Results: The mean heart rate and PSI decreased significantly and SDNN increased significantly in the morning compared to the afternoon. There was no significant difference except RMSSD in HRV conducted at 2 hours intervals in the afternoon. Age had a significant difference in SDNN and TP, and exercise in average heart rate. Age, weekly exercise frequency, and monthly drinking frequency showed significant correlations with HRV indicators. As a result of multiple regression analysis, monthly drinking frequency was a variable that had a significant influence on TP. Conclusions: The results of the tests performed with short interval were relatively consistent, and when comparing the results of the afternoon and the next morning, there were significant differences in several indicators. In the future, the number of HRV measurements should be increased and a larger-scale follow-up study including more subjects will be needed.

The Effect of Parenting Stress on Parenting Efficacy in Families with Children with Disabilities: Mediating Effects of Family Organization Patterns in the era of IoT (사물인터넷시대에 장애아동을 둔 가족의 양육스트레스가 양육효능감에 미치는 영향: 가족조직패턴의 매개효과를 중심으로)

  • Choi, Jang-Won;Jang, Daeyeon
    • Journal of Internet of Things and Convergence
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    • v.8 no.3
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    • pp.47-54
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    • 2022
  • The purpose of this study was to examine the mediating effect of family organization patterns of family resilience on the relationship between parenting stress and parenting efficacy. A total of 263 participants who have children with disabilities participated in this study by responding to the following questionnaires: Parenting Stress Index(PSI), Family Resilience Scale, Parenting Efficacy Scale. The collected data were analyzed using SPSS 25.0 and Amos 22.0. The main findings were as follows. There was a significant partial mediating effect of family organization patterns of family resilience on the relationship between parenting stress and parenting efficacy. The results of this study can provide useful information for family who have children with disabilities. suggestions for future study were discussed.

Study on Neuron Activities for Adversarial Examples in Convolutional Neural Network Model by Population Sparseness Index (개체군 희소성 인덱스에 의한 컨벌루션 신경망 모델의 적대적 예제에 대한 뉴런 활동에 관한 연구)

  • Youngseok Lee
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.16 no.1
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    • pp.1-7
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    • 2023
  • Convolutional neural networks have already been applied to various fields beyond human visual processing capabilities in the image processing area. However, they are exposed to a severe risk of deteriorating model performance due to the appearance of adversarial attacks. In addition, defense technology to respond to adversarial attacks is effective against the attack but is vulnerable to other types of attacks. Therefore, to respond to an adversarial attack, it is necessary to analyze how the performance of the adversarial attack deteriorates through the process inside the convolutional neural network. In this study, the adversarial attack of the Alexnet and VGG11 models was analyzed using the population sparseness index, a measure of neuronal activity in neurophysiology. Through the research, it was observed in each layer that the population sparsity index for adversarial examples showed differences from that of benign examples.

Measurement of Residual Stress Distribution in the Depth Direction of Annealed Materials of Lapped Bearing Steel Using Weighted Averaging Analysis Method (가중평균 해석법을 이용한 래핑된 베어링강 어닐링재료의 깊이방향에 대한 잔류응력분포 측정)

  • Chang-Suk Han;Chan-Woo Lee
    • Korean Journal of Materials Research
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    • v.33 no.5
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    • pp.205-213
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    • 2023
  • This paper reports the results of an experimental examination using X-rays to test annealing materials for lapped bearing steel (STB2), to confirm the validity of the weighted averaging analysis method. The distribution behavior for the α𝜓-sin2𝜓 diagram and the presence or absence of differences in the peak method, half-value breadth method, and centroid method were investigated. When lapping the annealed bearing steel (STB2) material, a residual stress state with a non-directional steep gradient appeared in the surface layer, and it was found that the weighted averaging analysis method was effective. If there is a steep stress gradient, the sin2𝜓 diagram is curved and the diffraction intensity distribution curve becomes asymmetric, resulting in a difference between the peak method, half-value breadth method, and centroid method. This phenomenon was evident when the stress gradient was more than 2~3 kg/mm2/㎛. In this case, if the position of the diffraction line is determined using the centroid method and the weighted averaging analysis method is applied, the stress value on the surface and the stress gradient under the surface can be obtained more accurately. When the stress gradient becomes a problem, since the curvature of the sin2𝜓 diagram appears clearly in the region of sin2𝜓 > 0.5, it is necessary to increase the inclination angle 𝜓 as much as possible. In the case of a lapping layer, a more accurate value can be obtained by considering 𝜎3 in the weighted averaging analysis method. In an isotropic biaxial residual stress state, the presence or absence of 𝜎3 can be determined as the presence or absence of strain for sin2𝜓≈0.4.

Effect of inwards FDI on new venture creation, industrialization and economic growth in Russia: A timeseries ARDL approach

  • Kristina, Yuryeva;He, Zhengquan
    • Asia Pacific Journal of Business Review
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    • v.7 no.1
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    • pp.1-21
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    • 2022
  • This research aimed to clarify the impacts casted by inwards FDI on New venture creation, industrialization, and the economic growth of Russia. For all of these variables, data was taken about Russia from the site of The World Bank, and the selected duration was from 1995 to 2019. The total duration of the data taken was from 24 years. The time duration was well enough for applying the A.R.D.L. approach to the time series data of the study. This research used the unit root test to know the presence of the unit root for each variable, the lag order selection was made for the data, the bounds cointegration test was also applied, and ARDL Model was used to know about the different effects. With the help of the results derived, it was observed that the impact of private sector investment on new venture creation is significant. In contrast, foreign direct investment and research and development (R&D) effects on new venture creation are insignificant. It was also observed from the results that the impact of R&D on industrialization in Russia is significant, while the effects of FDI and the impact of private sector investment on industrialization in Russia is insignificant. We have fund that the effect of FDI and the impact of private sector investment on the economic growth of Russia is significant. In contrast, the impact of R&D is insignificant to the economic growth of Russia. The study is of great significance as it has raised the importance of R&D for industrialization, FDI, and PSI for economic growth and new venture creation for developing countries.