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11.
Murat Dursun Huseyin Besiroglu Suleyman Sami Cakir Alper Otunctemur Emin Ozbek 《The aging male》2018,21(3):187-192
Objective: Visceral adipose index (VAI) is a novel parameter for the evaluation of visceral obesity. As we know that obesity is a risk factor for erectile dysfunction (ED). So, in this study, we compared the VAI levels between the men with ED and without ED.Materials and method: A total of 177 men were included in the study. Ninety-five men with ED and 82 men without ED (control). All men were evaluated for ED by Index of Erectile Function-5 items (IIEF-5). VAI levels were calculated using body mass index, high density lipoprotein and tryglyceride levels.Results: Mean age was 53.5 (38–69) in men who have ED and 53.1 (34–69) in control. The men with ED had higher body mass index (BMI), triglyceride (TG) levels, higher waist circumference (WC) and lower high-density lipoprotein-cholesterol (HDL-C) levels. Mean VAI level was 5.18?±?2.50 in study group and 3.47?±?1.76 in control goup, respectively. VAI levels were statistically higher in men with ED (p?.001).Discussion: The simplicity of WC and BMI measurement and TG and HDL assessment, make VAI an easily applicable index for the evaluation of visceral fat dysfunction. VAI can be useful index for the evaluation and calculation of erectile dysfunction risk. 相似文献
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Bimodal mixture Weibull distribution being a special case of mixture Weibull distribution has been used recently as a suitable model for heterogeneous data sets in many practical applications. The bimodal mixture Weibull term represents a mixture of two Weibull distributions. Although many estimation methods have been proposed for the bimodal mixture Weibull distribution, there is not a comprehensive comparison. This paper presents a detailed comparison of five kinds of numerical methods, such as maximum likelihood estimation, least-squares method, method of moments, method of logarithmic moments and percentile method (PM) in terms of several criteria by simulation study. Also parameter estimation methods are applied to real data. 相似文献
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Yuwen Chen Asoo J. Vakharia Aydin Alptekinolu 《Production and Operations Management》2008,17(6):587-598
Motivated by the proliferation of multifunction products, we investigate product portfolio decisions of a single firm by analyzing the impact of three major factors. First, because multifunction products provide complete or partial functionalities of single‐function products, we incorporate substitution or cannibalization effects between the potential products. Second, we explicitly model the variable costs of manufacturing the single‐function and multifunction products. Third, we examine the firm's pricing decisions because of their impact on the degree of cannibalization between the multifunction product and one or more single‐function products. Using an economic model, we first characterize the firm's optimal product portfolio (through a quantity‐based decision), which in turn determines the market equilibrium prices for each product in its portfolio. Some of the unique insights stemming from our analysis are: (a) the optimal product portfolio choice is driven primarily by maximum profit margins for the single‐function products weighted by the demand substitution effects; and (b) from a product design perspective, the complete functionality of the base single‐function product is always included in the optimal product offering, but this is not necessarily the case with the complete functionality of the nonbase single‐function product. 相似文献
14.
Objective: To evaluate the association between visceral adiposity index (VAI) - a novel indicator for the assessment of visceral adipose tissue and prostate enlargement in non diabetic patients.Material and methods: Four hundred patients who were admitted to the Urology clinic between January and December 2014 with complaints of BPH(benign prostatic hyperplasia )/LUTS(male lower urinary tract symptoms)were enrolled in this cross-sectional study. Patients were divided into two groups according to their prostate volume and international prostate symptom score (IPSS) value. They were compared in terms of age, body mass index (BMI), VAI, prostate volume, PSA, post micturional residual volume (PMRV), uroflowmetry Q max value, triglyceride (TG), high density lipoprotein-cholesterol (HDL-C) and fasting blood sugar (FBS).Results: Although univariate analyses reveal that age, BMI, waist circumference (WC), FBS, TG, HDL-C level and TG/HDL ratio were correlated with prostate volume, only age [1.125 OR (1.088–1.164), p?=?.00001], BMI [1.119 OR (1.040–1.204), p?=?.003], TG [1.043 OR (1.016–1.071), p?=?.002], HDL-C [0.923 OR (0.860–0.990), p?=?.025] and VAI [1.194 OR (1.110–1.305), p?=?.011] were statistically significant in multivariate analysis. A positive correlation was found between VAI value and prostate volume in the Spearman correlation test (r?=?0.29, p?=?.00001). The calculated area under the curve (AUC) for prostate volumes of 30, 40 and 50?ml were 0.680 (0.621–0.738), 0.625 (0.570–0.681) and 0.590 (0.528–0.652), respectively.Conclusion: Our study revealed a positive correlation between VAI and prostate volume. Our results are needed to be tested with well-designed randomized prospective cohort studies. 相似文献
15.
C E Aydin 《Journal of health and social behavior》1989,30(2):163-179
This paper explores the effects of computerized medical information systems on the occupational communities of health care professionals in hospitals. Interviews were conducted with informants from the pharmacy and nursing departments at two hospitals currently using medical information systems for communicating physicians' medication orders from the nursing station to the pharmacy. Results showed changes in tasks for both pharmacy and nursing, resulting in increased interdependence between the two departments. This interdependence was accompanied by improved communication and cooperation, providing an opportunity to encourage better working relationships between departments. The use and maintenance of the common computerized data base became a superordinate goal for the two groups, with the computer system itself as the topic of communication. 相似文献
16.
Objectives: To assess the association between triglyceride (TG)/high density lipoprotein (HDL) ratio and benign prostate hyperplasia/lower urinary tract symptoms (BPH/LUTS).Methods: Four hundred patients who were admitted to the Urology Clinic between January and December 2014 with complaints of BPH/LUTS were enrolled in this cross-sectional study. Patients were divided into two groups according to their International Prostate Symptom Score and prostate volume (PV). They were compared in terms of age, body mass index (BMI), PV, PSA, post micturional residual volume, uroflowmetry Q max value, fasting blood sugar, TG and high density lipoprotein-cholesterol (HDL-C) level and TG/HDL ratio.Results: Although univariate analyses reveal that age, BMI, waist circumference (WC), FBS, TG, HDL-C level, and TG/HDL ratio were correlated with PV, only age [1.125 OR (1.088–1.164), p?=?.00001], BMI [1.119 OR (1.040–1.204), p?=?.003], TG [(1.043 OR (1.016–1.071), p?=?.002], HDL-C [(0.923 OR (0.860–0.990), p?=?.025], and TG/HDL ratio [(1.224 OR (1.130–1.315), p?=?.014] were statistically significant in multivariate analysis. The calculated area under the curve (AUC) for PV of 30?ml, 40?ml, and 50?ml was 0.668 (0.608–0.727), 0.617 (0.561–0.673), and 0.592 (0.530–0.654), respectively.Conclusions: Our results indicate that the TG/HDL ratio correlates with enhancement in PV. Further studies are warranted to better evaluate this relationship. 相似文献
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18.
Dursun Aydin 《统计学通讯:模拟与计算》2013,42(9):2587-2611
ABSTRACTIn this paper, we propose modified spline estimators for nonparametric regression models with right-censored data, especially when the censored response observations are converted to synthetic data. Efficient implementation of these estimators depends on the set of knot points and an appropriate smoothing parameter. We use three algorithms, the default selection method (DSM), myopic algorithm (MA), and full search algorithm (FSA), to select the optimum set of knots in a penalized spline method based on a smoothing parameter, which is chosen based on different criteria, including the improved version of the Akaike information criterion (AICc), generalized cross validation (GCV), restricted maximum likelihood (REML), and Bayesian information criterion (BIC). We also consider the smoothing spline (SS), which uses all the data points as knots. The main goal of this study is to compare the performance of the algorithm and criteria combinations in the suggested penalized spline fits under censored data. A Monte Carlo simulation study is performed and a real data example is presented to illustrate the ideas in the paper. The results confirm that the FSA slightly outperforms the other methods, especially for high censoring levels. 相似文献
19.
By using exact integer programming (IP) (integer programming in infinite precision) bounds on the word-length patterns (WLPs) and generalized word-length patterns (GWPs) for fractional factorial designs are improved. In the literature, bounds on WLPs are formulated as linear programming (LP) problems. Although the solutions to such problems must be integral, the optimization is performed without the integrality constraints. Two examples of this approach are bounds on the number of words of length four for resolution IV regular designs, and a lower bound for the GWP of two-level orthogonal arrays. We reformulate these optimization problems as IP problems with additional valid constraints in the literature and improve the bounds in many cases. We compare the improved bound to the enumeration results in the literature to find many cases for which our bounds are achieved. By using the constraints in our integer programs we prove that f(16λ,2,4)?9 if λ is odd where f(2tλ,2,t) is the maximum n for which an OA(N,n,2,t) exists. We also present a theorem for constructing GMA OA(N,N/2-u,2,3) for u=1,…,5. 相似文献
20.
Objectives: To investigate the prevalence and severity of varicocele in adult population over the age of 40. We also measured testicular size, consistency, and total testosterone levels with an aim to observe the effect of varicocele on testis as men age.Methods: Two hundred twenty-four patients with varicocele, 241 patients without varicocele who admitted to our clinic were enrolled in the study. We stratified participants by four age groups (40–49, 50–59, 60–69, >70?yr). Patients were grouped according to varicocele grade and laterality. The morning testosterone level was drawn. The subgroups were compared with each other.Results: Overall, varicocele prevalence was 48%. Of the patients, 104 had unilateral, 120 had bilateral varicocele. Of the patients with varicocele, 62 (13.30%) were found as grade 3, 99 (21.10%) were grade 2, and 63 (13.60%) were grade 1. The percentages of smaller testes in grade 1, grade 2, and grade 3 varicocele group were 20.60, 79.80, and 88.70 and a significant association was detected. Age stratification of the data revealed the smaller and soft testis prevalence as well as higher grade varicocele prevalance increased in older age groups.Conclusions: Varicocele presence is associated with lower testicular size, softer testicular consistency, and lower testosterone levels, especially in older patients with bilateral and high-grade varicocele. 相似文献