Search Results

Now showing 1 - 10 of 57
  • Article
    Citation - WoS: 32
    Electrospun Essential Oil-Polycaprolactone Nanofibers as Antibiofilm Surfaces Against Clinical Candida Tropicalis Isolates
    (Springer, 2019) Sahal, Gulcan; Nasseri, Behzad; Ebrahimi, Aliakbar; Bilkay, Isil Seyis
    ObjectiveAs an approach to prevent biofilm infections caused by Candida tropicalis on various surfaces, determination of effect of biodegradable polycaprolactone nanofibers (PCLNFs) with different concentrations of two different essential oils were tested in this study.ResultsBoth of the tested essential oils exhibited antifungal effect (minimal inhibitory concentration; 0.25-0.49 mu L/mL, minimal fungicidal concentration; 0.25-0.49 mu L/mL, depending on the C. tropicalis strain) (Zone of inhibition caused by 500 L/mL concentration of oils; 28-56mm). 0, 2, 4% clove oil PCLNFs and 0, 2, 4% red thyme oil-PCLNFs were free from bead formation and uniform in diameter. Diameters of all essential oil containing PCLNFs were ranged from 760 to 1100nm and were significantly different from 0% essential oil-PCLNF (P<0.05). 0, 2, 4% clove oil-PCLNFs were significantly more hydrophobic compared to 8% clove oil-PCLNF (P<0.01), whereas 0% and 2% red thyme oil-PCLNFs were significantly more hydrophobic compared to 4% and 8% red thyme oil PCLNFs (P<0.01). Highest amount of biofilm inhibition was observed by 4% clove oil-PCLNF and by 4% red thyme oil-PCLNF.ConclusionsClove and red thyme oils may be used not only as antifungals but also as biofilm inhibitive agents on surfaces of biomaterials that are frequently contaminated by C. tropicalis, when they are incorporated into PCLNFs.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Principal and Nonprincipal Solutions of Impulsive Dynamic Equations: Leighton and Wong Type Oscillation Theorems
    (Springer, 2023) Zafer, A.; Akgol, S. Dogru; Doğru Akgöl, S.
    Principal and nonprincipal solutions of differential equations play a critical role in studying the qualitative behavior of solutions in numerous related differential equations. The existence of such solutions and their applications are already documented in the literature for differential equations, difference equations, dynamic equations, and impulsive differential equations. In this paper, we make a contribution to this field by examining impulsive dynamic equations and proving the existence of such solutions for second-order impulsive dynamic equations. As an illustration, we prove the famous Leighton and Wong oscillation theorems for impulsive dynamic equations. Furthermore, we provide supporting examples to demonstrate the relevance and effectiveness of the results.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 7
    Which Is Better To Predict Erectile Dysfunction and Male Sexual Function in the Context of Metabolic Syndrome: Triglyceride-Glucose Index or Visceral Adiposity Index?: a Retrospective Cross-Sectional Study
    (Springer, 2024) Bolat, Mustafa Suat; Bolat, Ipek Akalin; Dundar, Cihad; Asci, Ramazan
    PurposeMany factors influence male sexual function, including metabolic disorders such as metabolic syndrome (MetS). We aimed to investigate the effects of two metabolic indices, the triglyceride-glucose (TyG) index and the visceral adiposity index (VAI), on male sexual function.MethodsA total of 400 men having sexual dysfunction were included. Anthropological data, comorbidities were recorded. Serum total testosterone, prolactin, and estradiol levels were recorded. Sex-specific VAI was calculated using the [(WC/39.68) + (1.88xMI)] x (TG/1.03) x (1.31/HDL) formula and using Ln (fasting triglycerides) x (fasting glucose)/2] formula, TyG index was calculated. Turkish-validated 15-item long-form of the International Index of Erectile Dysfunction (IIEF) questionnaire and male sexual health questionnaire (MSHQ) were used for erectile function and ejaculatory function, respectively. The ROC analysis was used to evaluate the predictive abilities of TyG and VAI cut-off values for ED risk.ResultsA higher TyG index and VAI were associated with an increased risk of ED. The presence of MetS further worsened sexual function, with lower scores in sexual satisfaction, orgasm, desire, and general satisfaction. The TyG index and VAI showed similar predictive abilities for ED. Patients with MetS had worse ejaculation quality compared to those without MetS.ConclusionsThese findings highlight the potential of the TyG index and VAI as convenient tools for predicting and assessing sexual dysfunction in men, particularly in the context of metabolic disorders. Early detection and intervention for metabolic syndrome and insulin resistance may help to mitigate their negative impact on male sexual function.
  • Article
    The Relationship between Perinatal Grief and Spiritual Well-Being in Women Experiencing Termination due to Fetal Anomaly in Türkiye
    (Springer, 2025) Sari, Tugba; Gemicioglu, Sirin Harkin; Harkin Gemicioğlu, Şirin
    Pregnancy termination is a significant event in women's lives and can be considered a traumatic experience that can assess grief reactions. Couples who accept the decision to have a medical termination due to fetal anomaly face not only anxiety and feelings of loss, but also difficulties adapting to and coping with the termination process. This study aims to examine the relationship between perinatal grief and spiritual well-being in women who experience termination due to fetal anomaly. The study sample consisted of 256 women who had undergone termination during pregnancy. Data were analyzed using descriptive statistics (percentage, mean, standard deviation), the Mann-Whitney U test for independent samples, the Kruskal-Wallis test, Spearman correlation, and multiple linear regression analyses. The participants' mean score on the Perinatal Grief Scale was 112.87 +/- 15.04. The spiritual well-being scale subscale scores were 56.13 +/- 8.69 for the transcendence subscale, 25.27 +/- 2.94 for the harmony with nature subscale, and 26.58 +/- 3.18 for the anomie subscale. The correlation between the mean scores of the scales indicated that perinatal grief level was positively and significantly related to both the transcendence (r = 0.454; p < .001) and harmony with nature (r = 0.571; p < .001) subscales, while there was a strong negative correlation between perinatal grief and the anomie subscale (r = -0.762; p < .001). In conclusion, the study results indicate that perinatal grief is significantly related to various dimensions of spiritual well-being. These findings support the idea that supporting spiritual well-being in individuals experiencing perinatal grief can strengthen psychosocial adjustment.
  • Article
    Citation - WoS: 13
    Citation - Scopus: 14
    Improved Global Robust Stability for Interval-Delayed Hopfield Neural Networks
    (Springer, 2008) Singh, Vimal
    A modified form of a recent criterion for the global robust stability of interval-delayed Hopfield neural networks is presented. The effectiveness of the modified criterion is demonstrated with the help of an example.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 7
    On the Classification of Modulation Schemes Using Higher Order Statistics and Support Vector Machines
    (Springer, 2022) Coruk, Remziye Busra; Gokdogan, Bengisu Yalcinkaya; Benzaghta, Mohamed; Kara, Ali
    The recognition of modulation schemes in military and civilian applications is a major task for intelligent receiving systems. Various Automatic Modulation Classification (AMC) algorithms have been developed for this purpose in the literature. However, classification with low computational complexity as well as reasonable processing time is still a challenge. In this paper, a feature-based approach along with various classifiers is employed based on statistical features as well as higher-order moments and cumulants. An over-the-air (OTA) recorded dataset consisting of four analog and ten digital modulation schemes are used for testing the proposed method at 0-20 dB SNR. The overall accuracy for quadratic Support Vector Machine (SVM) is found to be as high as 98% at 10 dB. The comparison of the results with other AMC papers published in the literature indicates that the proposed method present higher accuracy, especially for realistic channel induced OTA dataset.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 2
    Birman-Hilden Property of Covering Spaces for Nonorientable Surfaces
    (Springer, 2020) Atalan, F.; Medetogullari, E.
    Let p : (N) over tilde -> N be a finite covering space for nonorientable surfaces, where chi((N) over tilde) < 0. We study whether or not p has the Birman-Hilden property.
  • Article
    Citation - WoS: 20
    Citation - Scopus: 15
    Assessment of Shock Models for a Particular Class of Intershock Time Distributions
    (Springer, 2022) Kus, Coskun; Tuncel, Altan; Eryilmaz, Serkan
    In this paper, delta and extreme shock models and a mixed shock model which combines delta-shock and extreme shock models are studied. In particular, the interarrival times between successive shocks are assumed to belong to a class of matrix-exponential distributions which is larger than the class of phase-type distributions. The Laplace -Stieltjes transforms of the systems' lifetimes are obtained in a matrix form. Survival functions of the systems are approximated based on the Laplace-Stieltjes transforms. The results are applied for the reliability evaluation of a certain repairable system consisting of two components.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    An Empirical Analysis of the Average Plant Start-Up Size in Turkish Manufacturing Industries
    (Springer, 2012) Cilasun, Seyit Mumin; Gunalp, Burak
    Many studies have found start-up size of a firm to be an important determinant of its subsequent performance and probability of survival. The aim of this study is to investigate the determinants of average plant start-up size in 51 four-digit Turkish manufacturing industries for the period 1993-1999. The results of the study suggest that while industry characteristics such as industry growth rate and capital intensity have a positive impact on the average plant start-up size, industrial concentration, import penetration, and the change in research and development expenditures are negatively associated with the same variable. In addition, the macroeconomic environment is also an important determinant of the choice of plant start-up size. Finally, we find evidence that may indicate 'following' (herd) behavior in Turkish manufacturing industries.
  • Article
    Citation - WoS: 22
    Citation - Scopus: 23
    On Residual Lifetime of Coherent Systems After the rth Failure
    (Springer, 2013) Eryilmaz, Serkan
    In this article we study the residual lifetime of a coherent system after the rth failure, i.e. the time elapsed from the rth failure until the system failure given that the system operates at the time of the rth failure. We provide a mixture representation for the corresponding residual lifetime distribution in terms of signature. We also obtain some stochastic ordering results for the residual lifetimes.