• 제목/요약/키워드: predictor models

검색결과 180건 처리시간 0.026초

The Absence of Atrial Contraction as a Predictor of Permanent Pacemaker Implantation after Maze Procedure with Cryoablation

  • Jeon, Chang-Seok;Shim, Man-shik;Park, Seung-Jung;Jeong, Dong Seop;Park, Kyoung-Min;On, Young Keun;Kim, June Soo;Park, Pyo Won
    • Journal of Chest Surgery
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    • 제50권3호
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    • pp.163-170
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    • 2017
  • Background: The absence of atrial contraction (AC) after the maze procedure has been reported to cause subsequent annular dilatation and to increase the risk of embolic stroke. We hypothesized that the lack of AC could increase the risk of permanent pacemaker (PPM) implantation in patients undergoing the maze procedure. Methods: In 376 consecutive patients who had undergone a cryo-maze procedure and combined valve operation, recovery of AC was assessed at baseline and at immediate (${\leq}2$ weeks), early (${\leq}1$ year, $4.6{\pm}3.8$ months), and late (>1 year, $3.5{\pm}1.1$ years) postoperative stages. Results: With a median follow-up of 53 months, 10 patients underwent PPM implantation. Seven PPM implants were for sinus node dysfunction (pauses of $9.6{\pm}2.4$ seconds), one was for marked sinus bradycardia, and two were for advanced/complete atrioventricular block. The median (interquartile range) time to PPM implantation was 13.8 (0.5-68.2) months. Our time-varying covariate Cox models showed that the absence of AC was a risk factor for PPM implantation (hazard ratio, 11.92; 95% confidence interval, 2.52 to 56.45; p=0.002). Conclusion: The absence of AC may be associated with a subsequent risk of PPM implantation.

패션 앱을 이용한 모바일 쇼핑 태도 및 사용의도 영향요인 연구 -성별과 연령집단별 차이 비교- (A Study on the Determinants of Attitude toward and Intention to Use Mobile Shopping through Fashion Apps -Comparisons of Gender and Age Group Differences-)

  • 성희원
    • 한국의류학회지
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    • 제37권7호
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    • pp.1000-1014
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    • 2013
  • This study identifies the determinants that influence attitude toward and the intention to use mobile shopping services through fashion applications (apps) based on the technology acceptance model. In addition, gender and age group differences were examined. Data were collected from subjects who have used smartphone fashion related apps; subsequently, a total of 327 data were analyzed. About 46% of respondents were males, with a mean age of 34.4 years that ranged from 20 to 49 years old. Multiple regression models were developed based on the research model. Perceived usefulness, perceived ease of use, perceived enjoyment, perceived risks (security risk and quality risk), fashion involvement, and fashion app attributes (product attributes and service attributes) were employed as predictors of attitudes towards mobile shopping. Attitudes towards mobile shopping and subjective norms with the aforementioned variables measured the intention to use. Attitudes towards mobile shopping were predicted by perceived enjoyment, perceived usefulness, and service attributes. Attitudes toward mobile shopping and subjective norms were the most important predictors of the intention to use. Gender differences were found in that service attributes were significant for attitudes towards mobile shopping only in the male model. Age differences were also found and perceived usefulness was the most important predictor of attitudes toward mobile shopping among those in their 20's; however, perceived enjoyment was the most important among those in their 30's and 40's. Quality risk was only significant to explain intention to use among those in their 40's. The findings of this study are useful to understand the possibility of the adoption of mobile shopping though fashion apps and provide basic insight into market segmentation.

노인의 인식된 짐스러움과 죽음불안간의 관계에서 영성의 매개효과 검증 (Mediating Effects of Spirituality on the Relationship between Perceived Burdensomeness and Death Anxiety among the Elderly)

  • 김진숙;송명섭
    • 한국콘텐츠학회논문지
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    • 제17권12호
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    • pp.299-307
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    • 2017
  • 본 연구의 목적은 노인들의 인식된 짐스러움이 죽음불안에 미치는 영향력과 이 두 변수와의 관계에서 영성이 매개효과로 작용하는지 탐색하는 것이다. 본 연구 결과를 요약하면 다음과 같다. 첫째, 노인의 인식된 짐스러움은 불안에 이르는 경로와 영성이 죽음불안에 이르는 경로, 인식된 짐스러움이 죽음불안에 이르는 경로 모두에서 유의한 것으로 나타났다. 즉, 노인의 인식된 짐스러움이 높을수록 죽음불안이 높아졌고, 영성이 높을수록 죽음불안을 낮추는 것으로 나타났다. 또한 인식된 짐스러움이 죽음불안에 직접 영향을 미치는 경로와 인식된 짐스러움이 영성을 통해 죽음불안에 영향을 미치는 간접경로를 가정한 부분매개모형과 간접 경로만을 가정한 완전매개모형에서 영성의 매개효과는 유의한 것으로 나타났다. 즉, 인식된 짐스러움과 죽음불안과의 관계에서 인식된 짐스러움이 죽음불안에 직접적인 영향을 미치는 것으로 나타났지만 영성을 매개로 하여 간접적으로 미치는 영향력이 더 큰 것으로 나타났다. 본 연구결과는 죽음불안을 낮추기 위해서는 영성의 사회복지 실천적 개입이 중요하다는 점을 밝혔고 이 결과에 근거하여 실천적 제언을 하였다.

Outdoor Workers' Use of Sun Protection at Work and Leisure

  • Peters, Cheryl E.;Koehoorn, Mieke W.;Demers, Paul A.;Nicol, Anne-Marie;Kalia, Sunil
    • Safety and Health at Work
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    • 제7권3호
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    • pp.208-212
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    • 2016
  • Background: Outdoor workers are at risk of high ultraviolet radiation exposure, and may have difficulty using sun protection. The objectives were to determine the prevalence of sun protection behaviors in a sample of outdoor construction workers, and to assess which factors predict better sun protection practices. Methods: Participants were recruited via construction unions. Workers answered a questionnaire on demographics, skin cancer risk, sun protection behaviors, and job. Sun protection behavior scores (from questions on sunscreen use, sleeved shirt, hat, shade seeking, sunglasses) were calculated by converting Likert-scale answers to scores from 0 to 4, and taking the mean (separately for work and leisure). Determinants of sun protection behavior scores were examined for work and leisure using generalized linear models. Results: Seventy-seven workers had complete questionnaire data (participation 98%). Sun protection behaviors used most often were hats (79% often/always) and sleeved shirts (82% often/always); least prevalent were shade-seeking (8% often/always) and sunscreen (29% often/always). For both work and leisure scores, the strongest predictor was skin type, with fairer-skinned individuals having higher sun protection behavior scores. Workers had higher scores at work than on weekends. Workplaces that required hats and sleeved shirts for safety purposes had higher protection behavior scores. Conclusion: This high-participation rate cohort helps characterize sun protection behaviors among outdoor workers. Workers practiced better sun protection at work than on weekends, suggesting that workplace policies supportive of sun protection could be useful for skin cancer prevention in the construction industry.

Alterations of papilla dimensions after orthodontic closure of the maxillary midline diastema: a retrospective longitudinal study

  • Jeong, Jin-Seok;Lee, Seung-Youp;Chang, Moontaek
    • Journal of Periodontal and Implant Science
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    • 제46권3호
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    • pp.197-206
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    • 2016
  • Purpose: The aim of this study was to evaluate alterations of papilla dimensions after orthodontic closure of the diastema between maxillary central incisors. Methods: Sixty patients who had a visible diastema between maxillary central incisors that had been closed by orthodontic approximation were selected for this study. Various papilla dimensions were assessed on clinical photographs and study models before the orthodontic treatment and at the follow-up examination after closure of the diastema. Influences of the variables assessed before orthodontic treatment on the alterations of papilla height (PH) and papilla base thickness (PBT) were evaluated by univariate regression analysis. To analyze potential influences of the 3-dimensional papilla dimensions before orthodontic treatment on the alterations of PH and PBT, a multiple regression model was formulated including the 3-dimensional papilla dimensions as predictor variables. Results: On average, PH decreased by 0.80 mm and PBT increased after orthodontic closure of the diastema (P<0.01). Univariate regression analysis revealed that the PH (P=0.002) and PBT (P=0.047) before orthodontic treatment influenced the alteration of PH. With respect to the alteration of PBT, the diastema width (P=0.045) and PBT (P=0.000) were found to be influential factors. PBT before the orthodontic treatment significantly influenced the alteration of PBT in the multiple regression model. Conclusions: PH decreased but PBT increased after orthodontic closure of the diastema. The papilla dimensions before orthodontic treatment influenced the alterations of PH and PBT after closure of the diastema. The PBT increased more when the diastema width before the orthodontic treatment was larger.

Preoperative Neutrophil to Lymphocyte Ratio as a Prognostic Factor in Patients with Non-metastatic Renal Cell Carcinoma

  • Wen, Ru-Min;Zhang, Yi-Jing;Ma, Sha;Xu, Ying-Li;Chen, Yan-Su;Li, Hai-Long;Bai, Jin;Zheng, Jun-Nian
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권9호
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    • pp.3703-3708
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    • 2015
  • Background: The neutrophil-to-lymphocyte ratio (NLR) is a strong predictor of mortality in patients with colorectal, lung, gastric cancer, pancreatic and metastatic renal cell carcinoma. We here evaluated whether preoperative NLR is an independent prognostic factor for non-metastatic renal cell carcinoma (RCC). Materials and Methods: Data from 327 patients who underwent curative or palliative nephrectomy were evaluated retrospectively. In preoperative blood routine examination, neutrophils and lymphocytes were obtained. The predictive value of NLR for non-metastatic RCC was analyzed. Results: The NLR of 327 patients was $2.72{\pm}2.25$. NLR <1.7 and NLR ${\geq}1.7$ were classified as low and high NLR groups, respectively. Chi-square test showed that the preoperative NLR was significantly correlated with the tumor size (P=0.025), but not with the histological subtype (P=0.095)and the pT stage (P=0.283). Overall survival (OS) and disease-free survival (DFS) were assessed using the Kaplan-Meier method. Effects of NLR on OS (P=0.007) and DFS (P=0.011) were significant. To evaluate the independent prognostic significance of NLR, multivariate COX regression models were applied and identified increased NLR as an independent prognostic factor for OS (P=0.015), and DFS (P=0.019). Conclusions: Regarding patient survival, an increased NLR represented an independent risk factor, which might reflect a higher risk for severe cardiovascular and other comorbidities. An elevated blood NLR may be a biomarker of poor OS and DFS in patients with non-metastatic RCC.

소음성 청력손실이 혈압에 미치는 영향에 관한 조사연구 (A Study on the Influences of Noise Induced Hearing Loss to the Blood Pressure)

  • 김종화;이충렬
    • Journal of Preventive Medicine and Public Health
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    • 제20권2호
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    • pp.205-214
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    • 1987
  • For the purpose of evaluating the effect of noise induced hearing loss on the blood pressure, a cross-sectional study was conducted in 481 manufacturing industrial workers in Pusan area consisted of 275 workers from noisier plant (over 90 dB(A), high exposed group) and 206 workers from less noisy plant (below 85 dB(A), low exposed group) from April to Decepmber in 1985. The summarized results were as follows; 1) The degree of hearing loss according to the audible frequency was most notable in 4,000 Hz. 2) The prevalence of hypertension was 14.8% in total examined subjects. And also in 40 dB(A) hearing lost workers, there was no significant difference between high exposed group as 15.5% and low exposed group as 15.8%. 3) In 3 models analyzed by multiple regression technique to obtain the complexed extents of risk factors related to the diastolic blood pressure, especially model III which contain age, body mass index, smoking, alcohol and family history of hypertension, duration of work, noise exposure level and degree of hearing loss in high exposed group was most remarkable compared to the others. 4) The most potential predictor related to the diastolic pressure in high exposed group was the degree of hearing loss. And the next were body mass index, familial history of hypertension and age in order. But in the case of low exposed group, the potential predictors were body mass index, age and familial history of hypertension.

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예측제어기를 이용한 시간지연 보상 (Compensation of Time Delay Using Predictive Controller)

  • 허화라;박재한;이장명
    • 전자공학회논문지S
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    • 제36S권2호
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    • pp.46-56
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    • 1999
  • 제어기와 플랜트가 공간상으로 분리되어 폐루프 내부에 시간지연이 불가피하게 존재하는 제어시스템의 시간지연 문제를 보상하기 위하여 확률 모델에 기반하여 설계된 예측제어기를 제안한다. 예측제어기는 지연된 이전의 값들로부터 선형예측 기법과 확률함수를 이용하여 실제의 현재값을 추정하며, 이를 제어기에 적용하여 시간지연에 의하여 발생되는 문제점을 최소화하였다. 제안된 방법의 타당성을 검증하기 위하여 DC 서보모터 시스템에 본 알고리즘을 실현하였으며, 상이한 시간지연에 따른 제어시스템의 영향을 관측하였다. 실험결과에서 예측제어기는 시간지연에 대하여 PID 제어기보다 우수한 수렴특성을 나타내었으며, 제어기의 안정범위 내에서 허용할 수 있는 최대 시간지연 값도 증가시킬 수 있음을 보였다. 제안된 예측제어기는 플랜트의 모델링을 요구하지 않고 출력의 통계적 정보만을 사용하므로 모델링이 어려운 시스템의 제어나 PID 제어의 보상기로 활용할 수 있는 범용적인 기법이다.

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Clinicopathological Significance of S100A10 Expression in Lung Adenocarcinomas

  • Katono, Ken;Sato, Yuichi;Jiang, Shi-Xu;Kobayashi, Makoto;Saito, Keita;Nagashio, Ryo;Ryuge, Shinichiro;Satoh, Yukitoshi;Saegusa, Makoto;Masuda, Noriyuki
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권1호
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    • pp.289-294
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    • 2016
  • Background: S100A10, of the S100 protein family, is reported to be involved in cancer cell invasion and metastasis. The aims of the present study were to immunohistochemically examine S100A10 expression in surgically resected lung adenocarcinomas, and evaluate any relationships with clinicopathological parameters and prognosis of patients. Materials and Methods: S100A10 expression was immunohistochemically studied in 202 consecutive resected lung adenocarcinomas, and its associations with clinicopathological parameters were evaluated. Kaplan-Meier survival analysis and Cox proportional hazards models were used to estimate the effect of S100A10 expression on survival. Results: S100A10 expression was detected in 65 of the 202 (32.2%) lung adenocarcinomas, being significantly correlated with poorer differentiation (P =0.015), a higher pathological TNM stage (stages II and III) (P=0.004), more frequent and severe intratumoral vascular invasion (P=0.001), and a poorer prognosis (P=0.030). However, S100A10 expression was not an independent predictor of survival after controlling for clinicopathological factors. Conclusions: The present study reveals that S100A10 is expressed in a subset of lung adenocarcinomas, and this is related to some clinicopathological parameters, although further studies are required to confirm the correlation between S100A10 expression and prognosis of lung adenocarcinoma patients.

Application of Data Mining Techniques to Explore Predictors of HCC in Egyptian Patients with HCV-related Chronic Liver Disease

  • Omran, Dalia Abd El Hamid;Awad, AbuBakr Hussein;Mabrouk, Mahasen Abd El Rahman;Soliman, Ahmad Fouad;Aziz, Ashraf Omar Abdel
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권1호
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    • pp.381-385
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    • 2015
  • Background:Hepatocellular carcinoma (HCC) is the second most common malignancy in Egypt. Data mining is a method of predictive analysis which can explore tremendous volumes of information to discover hidden patterns and relationships. Our aim here was to develop a non-invasive algorithm for prediction of HCC. Such an algorithm should be economical, reliable, easy to apply and acceptable by domain experts. Methods: This cross-sectional study enrolled 315 patients with hepatitis C virus (HCV) related chronic liver disease (CLD); 135 HCC, 116 cirrhotic patients without HCC and 64 patients with chronic hepatitis C. Using data mining analysis, we constructed a decision tree learning algorithm to predict HCC. Results: The decision tree algorithm was able to predict HCC with recall (sensitivity) of 83.5% and precession (specificity) of 83.3% using only routine data. The correctly classified instances were 259 (82.2%), and the incorrectly classified instances were 56 (17.8%). Out of 29 attributes, serum alpha fetoprotein (AFP), with an optimal cutoff value of ${\geq}50.3ng/ml$ was selected as the best predictor of HCC. To a lesser extent, male sex, presence of cirrhosis, AST>64U/L, and ascites were variables associated with HCC. Conclusion: Data mining analysis allows discovery of hidden patterns and enables the development of models to predict HCC, utilizing routine data as an alternative to CT and liver biopsy. This study has highlighted a new cutoff for AFP (${\geq}50.3ng/ml$). Presence of a score of >2 risk variables (out of 5) can successfully predict HCC with a sensitivity of 96% and specificity of 82%.