• 제목/요약/키워드: nonparametric tests

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Relationship between sonorheometry parameters and laboratory values in a critical care setting in Italy: a retrospective cohort study

  • Antonio Romanelli;Renato Gammaldi;Alessandro Calicchio;Salvatore Palmese;Antonio Siglioccolo
    • Journal of Trauma and Injury
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    • 제36권3호
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    • pp.210-216
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    • 2023
  • Purpose: This preliminary retrospective cohort study analyzed the relationship between the parameters provided by sonorheometry device Quantra and the coagulation values obtained from standard venous blood samples in patients admitted in intensive care unit (ICU). Methods: We reviewed medical charts of 13 ICU adult patients in whom at least one coagulation study with Quantra was performed. The relationship between Quantra and laboratory data was analyzed with the Spearman rank correlation coefficient (rho). The 95% confidence interval (CI) was computed. A P-value <0.05 was considered statistically significant. Results: We collected 28 data pairs. Statistically significant moderate correlations were found for the following parameters: clot time (CT) and activated partial thromboplastin time (rho=0.516; 95% CI, 0.123-0.904; P=0.009; clot stiffness (CS) and the international normalized ratio (INR; rho=0.418; 95% CI, 0.042-0.787; P=0.039); INR and platelet contribution to CS (rho=0.459; 95% CI, 0.077-0.836; P=0.022); platelet count and platelet contribution to CS (PCS; rho=0.498; 95% CI, 0.166-0.825; P=0.008); and fibrinogen and fibrinogen contribution to CS (FCS; rho=0.620; 95% CI, 0.081-0.881; P=0.001). Conclusions: Quantra can provide useful information regarding coagulation status, showing modest correlations with the parameters obtained from laboratory tests. During diffuse bleeding, CT and FCS values can guide the proper administration of clotting factors and fibrinogens. However, the correlation of INR with CS and PCS can cause misinterpretation. Further studies are needed to clarify the relationship between Quantra parameters and laboratory tests in the critical care setting and the role of sonorheometry in guiding targeted therapies and improving outcomes.

기술 중소기업의 경영 특성에 대한 고성장 기업 결정 영향 요인분석: 4차 산업혁명기업과 일반 중소기업을 중심으로 (Analysis of the Factors Influencing the Management Characteristics of Tech SMEs in Determination of High-growth Firms: Focusing on Fourth Industrial Revolution Related Businesses and General SMEs)

  • 윤선중;서종현
    • 벤처창업연구
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    • 제16권6호
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    • pp.157-175
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    • 2021
  • 본 연구는 기술보증기금이 2017년부터 2019년까지 기술평가를 통하여 보증 지원한 기술 중소기업 중 3,214개 기업을 대상으로 4차 산업혁명 기업과 일반 중소기업으로 구분한 후 경영 특성이 고성장 기업 결정에 미치는 영향을 실증 분석하였다. 고성장 기업 판단은 OECD(2007)의 정의를 적용하여 최근 2년간 매출액 증가율이 연간 평균 20% 이상인 기업이다. 표본 대상의 두집단이 비정규분포를 따르고 있어 Mann-Whitney U test 비모수 검증으로 평균치 차이 분석을 하였다. 또한 정규성 가정이 덜 엄격한 이변량 로지스틱 회귀분석을 실시하였다. 독립변수는 대표자 역량, 인적자본 역량, 기술혁신 역량, 기본 특성, 지역더미, 기술수준 더미이다. 이에 대응하는 하위변수는 대표자 학력, 대표자 동업종 경험 수준, 상시 종업원, 연구 인력, 지식 재산권 수, 연구개발 투자금액, 기업 업력, 총자산, 지역_수도권, 지역_중부권, 기술수준_첨단기술, 기술수준_중기술이다. 분석결과, 4차 산업혁명 기업은 대표자 동업종 경험수준, 상시종업원, 기업업력, 총자산, 기술수준_첨단기술의 연구가설이 지지되었다. 일반 중소기업은 대표자 동업종 경험수준, 연구인력, 총자산, 지역_수도권의 연구가설이 지지되었다.

우리나라 도시배수시스템 설계를 위한 확률강우강도식의 유도 (A Derivation of Rainfall Intensity-Duration-Frequency Relationship for the Design of Urban Drainage System in Korea)

  • 이재준;이정식
    • 한국수자원학회논문집
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    • 제32권4호
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    • pp.403-415
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    • 1999
  • 본 연구에서는 우리나라 강우에 대한 대표 확률분포형을 결정하고 결정된 대표 확률분포형에 의거하여 확률강우강도식을 유도한다. 빈도해석에 널리 사용되는 11개 분포형에 대하여 모멘트법과 최우추정법 및 확률가중모멘트법으로 모수를 추정하고, 적정성이 있는 모수를 대상으로 적합도 검정을 실시하여 지속기간별로 각 지점의 적정분포형을 구한다. 전 지역의 강우 동질성을 검정하는 방법으로 비모수적 검정방법인 Mann-Whitney 검정과 Kruskal-Walls 검정을 실시하여 우리나라 전역을 대표할 수 있는 대표 적정분포형을 구한다, 강우의 동질성 검정을 실시한 결과, 우리나라 전역을 대표할 수 있는 적정분포형을 선정할 수 없었으며, 12개 지속기간에 대하여 강우의 동질성이 있는 여러 개의 권역으로 구분하여 권역별 대표 확률분포형을 결정하였다. I,II,V 권역에서는 GEV 분포,III,IV 권역에서는 TypeIII 극차분포가 대표 적정분포형으로 선정되었으며, 이들 대표 적정분포형으로부터 얻어진 확률강우량을 이용하여 확률강우강도식을 유도하였다.

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방사선사면허 시험 대비 모의고사 중심으로 대면 교육과 비대면 교육비교 분석 (A Comparative Analysis of Face-to-face and Non-face-to-face Education Based on the Mock Test for a Radiologist)

  • 김용완;안병주;이준행;김주미;여화연
    • 한국방사선학회논문지
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    • 제14권7호
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    • pp.923-930
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    • 2020
  • 2020년도는 COVID-19 위기 상황으로 인하여 불가피하게 전면 비대면 교육을 시행하게 되었다. 연구자는 방사선사면허대비 전국 보건 계열 방사선과 3학년, 방사선학과 4학년 학생들이 면허시험을 앞두고 실시한 대면 교육과 비대면 모의시험(2019년 1.2회, 2020년 1.2회)의 성적을 알아보기 위하여 전국 방사선학과 및 방사선과 48개 대학 중 5개의 대학을 선정하여 대면 교육과 비대면 교육(2019년 1,2회, 2020년 1,2회)의 성적을 1회 모의고사 시험에 대면 교육과 비대면 교육(2019년 1회, 2020년 1회)의 성적을 비교하여, 비모수 검정으로 통계를 분석한 결과, 이론(Z=-2.023, p<0.05), 응용(Z=-2.023, p<0.05), 실기(Z=-2.023, p<0.05) 모두 성적에 차이가 있는 것으로 나타났다. 2회 모의고사 시험에 대면 교육과 비대면 교육 (2019년 2회, 2020년 2회)의 성적을 비교하여, 비모수 검정으로 통계를 분석한 결과, 이론(Z=-2.023, p<0.05), 응용(Z=-2.023, p<0.05), 실기(Z=-1.753, p<0.05) 성적에 차이가 있는 것으로 나타났다. 모의고사 시험의 결과 비대면 교육이 대면교육에 비교해 성적이 저조함에 따라 강의 방법을 달리하거나, 학생들과 소통할 수 있는 다양한 교육 방법을 병행해야 할 것으로 사료된다.

Predictive Factors Determining Neoadjuvant Chemotherapy Outcomes in Breast Cancer - a Single Center Experience

  • Yu, Yang;Xiang, Hua;He, Xiang-Ming;Yang, Hong-Jian;Zong, Xiang-Yun
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권4호
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    • pp.2401-2406
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    • 2013
  • From January 1, 2008 to March 31, 2010, 101 patients with stage II-III breast cancer were enrolled in this study and subjected to an anthracycline-based neoadjuvant chemotherapy regimen with or without docetaxel. Surgery was performed after 2-6 cycles of chemotherapy, and the clinical response was determined by pathological and histochemical assessments. The clinical response rate, as indicated by complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD), were 6.9, 52.5, 36.6, and 4.0%, respectively. A multivariable correlation analysis indicated that the overall clinical response rate correlated with the number of metastatic lymph nodes, number of chemotherapy cycles, and vessel invasion status. Importantly, the CR rate was only associated with the number of chemotherapy cycles. Nonparametric tests failed to detect a correlation between HER2 or Topo $II{\alpha}$ status and clinical response to neoadjuvant chemotherapy in these patients. When they were stratified by HER2 or HR status, for HER2-positive patients the CR rate was associated with vessel invasion and Topo $II{\alpha}$ status. Based on our findings, we propose that HR, HER-2 and Topo $II{\alpha}$ are not putative predictive biomarkers of chemotherapy outcome for breast cancer patients. Topo $II{\alpha}$ expression level was only inversely correlated with CR rate among HR-positive patients. Importantly, the achievement of CR was largely related to the number of chemotherapy cycles.

Effect of missing values in detecting differentially expressed genes in a cDNA microarray experiment

  • Kim, Byung-Soo;Rha, Sun-Young
    • Bioinformatics and Biosystems
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    • 제1권1호
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    • pp.67-72
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    • 2006
  • The aim of this paper is to discuss the effect of missing values in detecting differentially expressed genes in a cDNA microarray experiment in the context of a one sample problem. We conducted a cDNA micro array experiment to detect differentially expressed genes for the metastasis of colorectal cancer based on twenty patients who underwent liver resection due to liver metastasis from colorectal cancer. Total RNAs from metastatic liver tumor and adjacent normal liver tissue from a single patient were labeled with cy5 and cy3, respectively, and competitively hybridized to a cDNA microarray with 7775 human genes. We used $M=log_2(R/G)$ for the signal evaluation, where Rand G denoted the fluorescent intensities of Cy5 and Cy3 dyes, respectively. The statistical problem comprises a one sample test of testing E(M)=0 for each gene and involves multiple tests. The twenty cDNA microarray data would comprise a matrix of dimension 7775 by 20, if there were no missing values. However, missing values occur for various reasons. For each gene, the no missing proportion (NMP) was defined to be the proportion of non-missing values out of twenty. In detecting differentially expressed (DE) genes, we used the genes whose NMP is greater than or equal to 0.4 and then sequentially increased NMP by 0.1 for investigating its effect on the detection of DE genes. For each fixed NMP, we imputed the missing values with K-nearest neighbor method (K=10) and applied the nonparametric t-test of Dudoit et al. (2002), SAM by Tusher et al. (2001) and empirical Bayes procedure by $L\ddot{o}nnstedt$ and Speed (2002) to find out the effect of missing values in the final outcome. These three procedures yielded substantially agreeable result in detecting DE genes. Of these three procedures we used SAM for exploring the acceptable NMP level. The result showed that the optimum no missing proportion (NMP) found in this data set turned out to be 80%. It is more desirable to find the optimum level of NMP for each data set by applying the method described in this note, when the plot of (NMP, Number of overlapping genes) shows a turning point.

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퇴행성 골관절염 환자에서 시행한 근위 경골 절골술 후 대퇴골의 회전과 임상결과의 상관관계 (Correlation between femoral rotation and clinical results after high tibial osteotomy in primary osteoarthritis patient)

  • 박상은;문상원
    • 대한정형외과스포츠의학회지
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    • 제10권2호
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    • pp.100-104
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    • 2011
  • 이 연구의 목적은 근위 경골 절골술 후 대퇴골의 회전각도와 슬관절 운동범위 및 주관적 환자 만족도 사이의 상관 관계를 분석하는 것이다. 2004년 6월부터 2008년 8월까지 고위 경골 절골술을 시행한 15명의 원발성 골 관절염 환자들이 연구 대상으로 수술 전 후 슬관절 CT를 시행하였다. 9명은 여자였으며 6명은 남자였다. 수술 전 후 슬관절의 CT를 촬영하여 대퇴골 회전 각도(TEA (Fig. 1) 및 Akagi's line (Fig. 2)으로 측정)를 백분율로 환산하여 분석하였으며 수술 후 슬관절 운동 각도와 주관적 만족도(Lysholm)의 상관관계를 확인하였다. 통계적 기법은 Kendall's 및 Spearman's nonparameter correlation coefficient 로 검정하였다. 결과상 대퇴골회전 정도와 수술 후 슬관절의 운동 각도는 의미 있는 상관 관계가 없으며 대퇴골 회전 정도와 수술후 환자의 주관적 만족도와는 의미 있는 상관 관계가 있었다. 따라서 이런 점을 알고 수술적 계획을 세운다면 보다 좋은 임상결과를 얻을 수 있을 것이다.

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Chemical Water Quality and Fish Component Analyses in the Periods of Before- and After-the Weir Constructions in Yeongsan River

  • Kwak, Sang Do;Choi, Ji-Woong;An, Kwang-Guk
    • Journal of Ecology and Environment
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    • 제39권1호
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    • pp.99-110
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    • 2016
  • The objective of this study was to analyze chemical water quality, ecological characteristics of fish compositions, and ecosystem health before- (Bwc; 2008-2009) and after-the weir construction (Awc; 2011-2012) at Juksan Weir and Seungchon Weir of Yeongsan River watershed. Suspended solids (SS) and chlorophyll-a (Chl-a) in Juksan Weir increased, whereas nutrients such as total nitrogen (TN) and total phosphorus (TP) decreased in the epilimnetic water. In Juksan and Seungchon weirs, fish species distribution analysis in the periods of Bwc and Awc showed that sensitive species were rare and tolerant species were dominant in the community. In the analysis of trophic guild, relative abundance of carnivore species are increased to 22% and 12%, respectively, after the constructions of Seungchon Weir and Juksan Weir. Mann-Whitney U-tests of nonparametric statistical analysis indicated that omnivore and carnivore species had significant differences (p < 0.05) between the Bwc and Awc. The massive population growth of an exotic species, Micropterus salmoides, was evident in Seungchon Weir to influence on the structures of fish communities. The model values of mean Index of Biological Integrity (IBI), based on fish assemblages, were < 15, which indicates "poor" condition in the river health, and the significant difference of IBI values was not found between the Bwc and Awc.

Comparative evaluation of NovaMin desensitizer and Gluma desensitizer on dentinal tubule occlusion: a scanning electron microscopic study

  • Joshi, Surabhi;Gowda, Ashwini Shivananje;Joshi, Chintan
    • Journal of Periodontal and Implant Science
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    • 제43권6호
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    • pp.269-275
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    • 2013
  • Purpose: In this study, the effect of calcium sodium phosphosilicate (NovaMin) desensitizing agent, which is a powder-based system, and hydroxyethyl methacrylate and glutaraldehyde (Gluma desensitizer), which is liquid-based system, on dentinal tubule occlusion was analyzed by scanning electron microscope. The effects of the above two along with one control group were compared to determine the more effective method of sealing the dentinal tubules after initial application. Methods: Twenty specimens were allocated to each of 3 groups: Control, Gluma desensitizer, and NovaMin. Two additional samples were also prepared and treated with Gluma and NovaMin; these samples were longitudinally fractured. The specimens were prepared from extracted sound human premolars and were stored in 10% formalin at room temperature. The teeth were cleaned of gross debris and then sectioned to provide one to two dentin specimens. The dentin specimens were etched with 6% citric acid for 2 minutes and rinsed in distilled water. Control discs were dried, and the test discs were treated with the desensitizing agents as per the manufacturer's instructions. The discs as well as longitudinal sections were later analyzed under the scanning electron microscope. The proportions of completely occluded, partially occluded, and open tubules within each group were calculated. The ratios of completely and partially occluded tubules to the total tubules for all the groups was determined, and the data was statistically analyzed using nonparametric tests and statistical significance was calculated. Results: NovaMin showed more completely occluded tubules ($0.545{\pm}0.051$) while Gluma desensitizer showed more partially occluded tubules ($0.532{\pm}0.075$). The differences among all the groups were statistically significant ($P{\leq}0.05$). Conclusion: Both materials were effective in occluding dentinal tubules but NovaMin appeared more promising in occluding tubules completely after initial application.

치면세마실습실 방문자의 구강관리용품 인지 및 사용에 영향을 미치는 요인 (Influential factors for recognition and use of oral care supplies by oral prophylaxis practice lab visitors)

  • 박인숙;정은주
    • 한국치위생학회지
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    • 제17권1호
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    • pp.133-144
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    • 2017
  • Objectives: The purpose of this study was to examine the oral health care of oral prophylaxis practice lab visitors, their recognition of oral care supplies, their use of oral care supplies by type, and influential factors for their recognition and use of oral care supplies. Methods: The subjects in this study were 275 people who visited an oral prophylaxis practice lab at a university located in an urban community. The visitors were respectively interviewed from March to June, 2016, and the data from 260 respondents who properly responded were analyzed, and data from 15 visitors who provided incomplete responsees were excluded. Statistical analysis was performed using the nonparametric tests, mann-whitney test and kruskal-wallis test, and multiple regression analysis using SPSS. Results: The mean score of oral care products was 2.25, the average degree of use was 0.09, and dental floss (0.29) was the most used oral care product. There was a significant difference between the groups according to gender (p<0.001), age (p<0.001) and marital status (p<0.001). Factors influencing the perception of oral care products were experience in brushing education and experience in oral care products education. Conclusions: The recognition of the oral prophylaxis practice lab visitors about oral care supplies and their use of the supplies were under the influence of oral health education. Therefore, sustained efforts should be directed into the development of efficient oral health care education programs that can inform people about the importance of oral health care, publicize oral care supplies, and encourage the use of these supplies.