• Title/Summary/Keyword: Characteristic curve

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Bioelectrical Impedance Analysis for Prediction of Early Complications after Gastrectomy in Elderly Patients with Gastric Cancer: the Phase Angle Measured Using Bioelectrical Impedance Analysis

  • Yu, Byunghyuk;Park, Ki Bum;Park, Ji Yeon;Lee, Seung Soo;Kwon, Oh Kyoung;Chung, Ho Young
    • Journal of Gastric Cancer
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    • v.19 no.3
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    • pp.278-289
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    • 2019
  • Purpose: Phase angle obtained using bioelectrical impedance analysis (BIA) provides a relatively precise assessment of the nutritional status of elderly patients. This study aimed to evaluate the significance of phase angle as a risk factor for complications after gastrectomy in elderly patients. Materials and Methods: We evaluated 210 elderly patients (aged ${\geq}65years$) who had undergone gastrectomy for gastric cancer between August 2016 and August 2017. The phase angle cutoff value was calculated using receiver operating characteristic curve analysis according to sex. A retrospective analysis regarding the correlation between early postoperative complications and well-known risk factors, including the phase angle, was performed. Results: Multivariate analysis revealed that the presence of two or more comorbidities (odds ratio [OR], 3.675) and hypoalbuminemia (OR, 4.059) were independent risk factors for overall complications, and female sex (OR, 2.993) was independent risk factor for severe complications. A low phase angle (OR, 2.901 and 4.348, respectively) and total gastrectomy (OR, 4.718 and 3.473, respectively) were independent risk factors for both overall and severe complications. Conclusions: Our findings show that preoperative low phase angle predicts the risk of overall and severe complications. Our findings suggest that BIA should be performed to assess the risk of postoperative complications in elderly patients with gastric cancer.

Usefulness of Predictors for Hepatotoxicity in Acetaminophen Poisoning Patient (아세트아미노펜 중독 환자에서 간독성 발생 예측인자들의 유용성)

  • Kim, Eun Young;Chung, Sung Phil;Ko, Dong Ryul;Kong, Tae Young;You, Je Sung;Choa, Min Hong;Kim, Min Joung
    • Journal of The Korean Society of Clinical Toxicology
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    • v.16 no.2
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    • pp.149-156
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    • 2018
  • Purpose: The purpose of this study was to determine whether hepatotoxicity could be predicted early using biochemical markers in patients with acetaminophen (AAP) poisoning and to assess the usefulness of predictive factors for acute liver injury or hepatotoxicity. Methods: This study was a retrospective observational study involving a medical records review. The participants were patients who were admitted to the emergency department (ED) with AAP overdose at two hospitals over a 10-year period. Demographic data, age, time from ingestion to visit, initial AAP level, initial hepatic aminotransferases, and initial prothrombin time were recorded. Acute liver injury was defined as a peak serum ALT >50 U/L or double the admission value, and hepatotoxicity was defined as a peak ALT >1,000 U/L. Receiver operating characteristic curve analyses were performed to compare the prognostic performance among variables. Results: A total of 97 patients were admitted to the ED with AAP overdose, of whom 26 had acute liver injury and 6 had hepatotoxicity. Acute liver injury was associated with the time interval after taking the drug, and hepatotoxicity was associated with the initial PT and the ALT level. The scoring system proposed by the authors has a significant ability to predict both acute liver injury and hepatotoxicity. Conclusion: To predict the prognosis of AAP poisoning patients, the time interval after taking AAP was important, and initial prothrombin time and ALT level were useful tests. Also a scoring system combining variables may be useful.

Analysis and Evaluation of the Distributed Control Braking System of Long Freight Car Brakes (장대화물열차의 분산제어 제동 시 연결기에 발생하는 충격력 해석 및 분석)

  • Cho, Byung Jin;Lee, Jeong Jun;Shim, Jae Seok;Koo, Jeong Seo;Mun, Hyung Seok
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.18 no.2
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    • pp.65-72
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    • 2019
  • In long freight trains, there is a brake time delay in neighboring freight cars, which causes damage and fractures in the couplers, especially at their knuckle. A problem in the couplers of the cars can cause derailment and damages of human life and property. In this study, maximum forces on the couplers are studied when a long freight car brakes with the brake delay time and coupler gap. We make a dynamic model of 50 freight cars and couplers, applying contact between the couplers and a characteristic curve to express the force and displacement of the buffers using SIMPACK, which is a multi-body dynamics program. We use EN 14531-2, which is a standard of freight car brakes, to verify the dynamic model. Then, we compare the analyzed impact force with the coupler knuckle standard after applying the two carriages of a locomotive in the model based on the dispersed double head control system. The result shows that all coupler gap conditions satisfy the infinite lifetime of the material when the brake delay time is 0.1 second.

Performance of mid-upper arm circumference to diagnose acute malnutrition in a cross-sectional community-based sample of children aged 6-24 months in Niger

  • Marshall, Sarah K;Monarrez-Espino, Joel;Eriksson, Anneli
    • Nutrition Research and Practice
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    • v.13 no.3
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    • pp.247-255
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    • 2019
  • BACKGROUND/OBJECTIVES: Accurate, early identification of acutely malnourished children has the potential to reduce related child morbidity and mortality. The current World Health Organisation (WHO) guidelines classify non-oedematous acute malnutrition among children under five using Mid-Upper Arm Circumference (MUAC) or Weight-for-Height Z-score (WHZ). However, there is ongoing debate regarding the use of current MUAC cut-offs. This study investigates the diagnostic performance of MUAC to identify children aged 6-24 months with global (GAM) or severe acute malnutrition (SAM). SUBJECTS/METHODS: Cross-sectional, secondary data from a community sample of children aged 6-24 months in Niger were used for this study. Children with complete weight, height and MUAC data and without clinical oedema were included. Using WHO guidelines for GAM (WHZ < -2, MUAC < 12.5 cm) and SAM (WHZ < -3, MUAC < 11.5 cm), the sensitivity (Se), specificity (Sp), predictive values, Youden Index and Receiver Operating Characteristic (ROC) curves were calculated for MUAC when compared with the WHZ reference criterion. RESULTS: Of 1161 children, 23.3% were diagnosed with GAM using WHZ, and 4.4% with SAM. Using current WHO cut-offs, the Se of MUAC to identify GAM was greater than for SAM (79 vs. 57%), yet the Sp was lower (84 vs. 97%). From inspection of the ROC curve and Youden Index, Se and Sp were maximised for MUAC < 12.5 cm to identify GAM (Se 79%, Sp 84%), and MUAC < 12.0 cm to identify SAM (Se 88%, Sp 81%). CONCLUSIONS: The current MUAC cut-off to identify GAM should continue to be used, but when screening for SAM, a higher cut-off could improve case identification. Community screening for SAM could use MUAC < 12.0 cm followed by appropriate treatment based on either MUAC < 11.5 cm or WHZ < -3, as in current practice. While the practicalities of implementation must be considered, the higher SAM MUAC cut-off would maximise early case-finding of high-risk acutely malnourished children.

The influence of different scan resolutions on the detection of proximal caries lesions

  • Ferreira, Liana Matos;Queiroz, Polyane Mazucatto;Santaella, Gustavo Machado;Wenzel, Ann;Groppo, Francisco Carlos;Haiter-Neto, Francisco
    • Imaging Science in Dentistry
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    • v.49 no.2
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    • pp.97-102
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    • 2019
  • Purpose: This study was conducted to evaluate the effect of different spatial resolutions of a photostimulable phosphor plate (PSP) radiography system on the detection of proximal caries lesions. Materials and Methods: Forty-five extracted human permanent teeth were radiographed using a PSP system (VistaScan Perio Plus) and scanned at the 4 resolutions (10 lp/mm, 20 lp/mm, 25 lp/mm, and 40 lp/mm) available in the system. Three independent examiners scored the images for the presence and absence of proximal caries lesions using a 5-point scale. The presence or absence of caries was confirmed by histological sections of the examined teeth (defined as the gold standard). Intra- and inter-observer reproducibility was calculated by the weighted kappa test. One-way analysis of variance with the post hoc Tukey test was used to compare the area under the receiver operating characteristic curve for the classifications made with each resolution. Results: For the detection of enamel lesions, the spatial resolution of 10 lp/mm was significantly superior to the other resolutions. However, the spatial resolution did not affect the detection of caries lesions in dentin (P>0.05). Conclusion: Spatial resolution may influence the accuracy of the detection of incipient caries lesions in radiographs with PSP plates. Images with low spatial resolution seem to be more appropriate for this purpose.

Oxygenation Index in the First 24 Hours after the Diagnosis of Acute Respiratory Distress Syndrome as a Surrogate Metric for Risk Stratification in Children

  • Kim, Soo Yeon;Kim, Byuhree;Choi, Sun Ha;Kim, Jong Deok;Sol, In Suk;Kim, Min Jung;Kim, Yoon Hee;Kim, Kyung Won;Sohn, Myung Hyun;Kim, Kyu-Earn
    • Acute and Critical Care
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    • v.33 no.4
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    • pp.222-229
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    • 2018
  • Background: The diagnosis of pediatric acute respiratory distress syndrome (PARDS) is a pragmatic decision based on the degree of hypoxia at the time of onset. We aimed to determine whether reclassification using oxygenation metrics 24 hours after diagnosis could provide prognostic ability for outcomes in PARDS. Methods: Two hundred and eighty-eight pediatric patients admitted between January 1, 2010 and January 30, 2017, who met the inclusion criteria for PARDS were retrospectively analyzed. Reclassification based on data measured 24 hours after diagnosis was compared with the initial classification, and changes in pressure parameters and oxygenation were investigated for their prognostic value with respect to mortality. Results: PARDS severity varied widely in the first 24 hours; 52.4% of patients showed an improvement, 35.4% showed no change, and 12.2% either showed progression of PARDS or died. Multivariate analysis revealed that mortality risk significantly increased for the severe group, based on classification using metrics collected 24 hours after diagnosis (adjusted odds ratio, 26.84; 95% confidence interval [CI], 3.43 to 209.89; P=0.002). Compared to changes in pressure variables (peak inspiratory pressure and driving pressure), changes in oxygenation (arterial partial pressure of oxygen to fraction of inspired oxygen) over the first 24 hours showed statistically better discriminative power for mortality (area under the receiver operating characteristic curve, 0.701; 95% CI, 0.636 to 0.766; P<0.001). Conclusions: Implementation of reclassification based on oxygenation metrics 24 hours after diagnosis effectively stratified outcomes in PARDS. Progress within the first 24 hours was significantly associated with outcomes in PARDS, and oxygenation response was the most discernable surrogate metric for mortality.

A study of the effectiveness of using the serum procalcitonin level as a predictive test for bacteremia in acute pyelonephritis

  • Lee, Ga Hee;Lee, Yoo Jin;Kim, Yang Wook;Park, Sihyung;Park, Jinhan;Park, Kang Min;Jin, Kyubok;Park, Bong Soo
    • Kosin Medical Journal
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    • v.33 no.3
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    • pp.337-346
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    • 2018
  • Objectives: Serum procalcitonin (PCT) is a specific biomarker that rises after bacterial infection, and levels of PCT are known to correlate with the severity and mortality of patients with pneumonia and sepsis. However, the usefulness of PCT levels in acute pyelonephritis is unknown. This study aimed to evaluate the effectiveness of using the PCT level as a predictive test for bacteremia in acute pyelonephritis. Methods: Between January 2012 and June 2013, 140 patients diagnosed with acute pyelonephritis were admitted to Haeundae Paik Hospital. Serum PCT, C-reactive protein (CRP), and white blood cell (WBC) levels at pre- and post- treatment were measured. Blood and urine cultures were obtained from all patients. The levels of PCT, CRP, and WBCs were each compared between the blood culture-positive and blood culture-negative groups to assess their effectiveness in predicting bacteremia. Results: Pre-treatment PCT level was 0.77 ng/mL (95% CI: 0.42-1.60 ng/mL) in the blood culture-negative group and 4.89 ng/mL (95% CI: 2.88-9.04 ng/mL) in the blood culture-positive group, and the increase between the two groups was statistically significant. The area under the receiver operating characteristic curve of PCT level for prediction of bacteremia was 0.728. A cut-off value of 1.23 ng/mL indicated a sensitivity of 79.0 % and specificity of 60.0 % for PCT level. Conclusions: Serum PCT level is a useful predictive test for bacteremia in acute pyelonephritis. Through the early detection of bacteremia, serum PCT level can help estimate the prognosis and predict complications such as sepsis.

Evaluation of Risk Factors for Uterine Myoma Diagnosed by Ultrasonography (초음파로 진단된 자궁근종의 위험인자 평가)

  • Yang, Sung-Hee
    • Journal of radiological science and technology
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    • v.44 no.4
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    • pp.307-313
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    • 2021
  • The purpose of this study was to analyze the risk factors for uterine myoma diagnosed by ultrasonography in Korea women and to evaluate the risk. Among the patients who visited the outpatient department of obstetrics and gynecology at I hospital in Busin between January 2019 and March 2021 for the purpose of examination, 98 patients in the experimental group diagnosed with uterine myoma and 163 patients in the normal control group without other diseases were retrospectively conducted. Among the general characteristics of the subjects, age, body mass index, parity, and menopause showed significant differences between the myoma group and the normal control group. ROC(receiver operating characteristic) curve analysis and logistic regression analysis were performed to obtain the cut off value and odds ratio that can predict the occurrence of uterine myoma. The cut off value for the prediction of uterine myoma was determined to be 30 years old and a body mass index of 23 kg/m2. After that adjusting for menopause, non menopausal cases with a body mass index of 23 kg/m2 and over 39 years of age had the highest odds ratio of 6.04. Therefore, premenopausal women over 40 years of age require regular checkups and thorough weight management. This study was conducted with a small number of subjects. Therefore, there is a limit to generalizing to all Korean women. However, based on this study if a large scale prospective study considering various variables is made, it can play a role as a predictive marker in early detection of uterine myoma.

Development of a New Similarity Index to Compare Time-series Profile Data for Animal and Human Experiments (동물 및 임상 시험의 시계열 프로파일 데이터 비교를 위한 유사성 지수 개발)

  • Lee, Ye Gyoung;Lee, Hyun Jeong;Jang, Hyeon Ae;Shin, Sangmun
    • Journal of Korean Society for Quality Management
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    • v.49 no.2
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    • pp.145-159
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    • 2021
  • Purpose: A statistical similarity evaluation to compare pharmacokinetics(PK) profile data between nonclinical and clinical experiments has become a significant issue on many drug development processes. This study proposes a new similarity index by considering important parameters, such as the area under the curve(AUC) and the time-series profile of various PK data. Methods: In this study, a new profile similarity index(PSI) by using the concept of a process capability index(Cp) is proposed in order to investigate the most similar animal PK profile compared to the target(i.e., Human PK profile). The proposed PSI can be calculated geometric and arithmetic means of all short term similarity indices at all time points on time-series both animal and human PK data. Designed simulation approaches are demonstrated for a verification purpose. Results: Two different simulation studies are conducted by considering three variances(i.e., small, medium, and large variances) as well as three different characteristic types(smaller the better, larger the better, nominal the best). By using the proposed PSI, the most similar animal PK profile compare to the target human PK profile can be obtained in the simulation studies. In addition, a case study represents differentiated results compare to existing simple statistical analysis methods(i.e., root mean squared error and quality loss). Conclusion: The proposed PSI can effectively estimate the level of similarity between animal, human PK profiles. By using these PSI results, we can reduce the number of animal experiments because we only focus on the significant animal representing a high PSI value.

Friction Characteristic of SCM44 Steel using Grease Lubricants (그리스 윤활유의 종류에 따른 SCM44의 마찰특성)

  • Kwon, Soon-Goo;Kwon, Soon-Hong;Kim, Won-Kyung;Choi, Won-Sik
    • Journal of the Korean Society of Industry Convergence
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    • v.23 no.6_2
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    • pp.917-926
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    • 2020
  • Friction mechanisms is a very important role in the industrial machinery. However, many experiments have been conducted to reduce the loss of energy resources and parts used due to friction because the friction force adversely affects parts, efficiency, noise, and the like of the power unit. Therefore, in this study, the friction coefficient according to the characteristics of the lubricant was measured to find out which Grease Lubricant maintains the low friction coefficient without being most affected by external conditions. A total of five grease lubricants were tested in this study: GHP CAL 301, GHP EP 2, GHP KG 10, GHP HPG 2, and GHP HTG 2. And the friction coefficient was conducted by changing the load conditions (2, 4, 6, 8, 10N) and rotational speed (24, 48, 67, 86, 105, 124, 143, 162vrpm) using a pin-on-disk wear test system. Also, duty number were calculated. As a result, it was confirmed that in all grease lubricants, the speed did not significantly affect the friction coefficient, and it was confirmed that in all lubricants, the size of the friction coefficient decreased as the load increased from a small load to a large load. In addition, it was determined from the experimental results that GHP EP 2 is the most suitable as a grease lubricant and GHP CAL 301 is not the most suitable.