Investigation of antimicrobial activity and entA and entB genes in Enterococcus faecium and Enterococcus faecalis strains isolated from naturally fermented Turkish white cheeses

Togay, Sine Ozmen,Ay, Mustafa,Guneser, Onur,Yuceer, Yonca Karagul 한국식품과학회 2016 Food Science and Biotechnology Vol.25 No.6

In this research, the antagonistic effects of Enterococcus faecalis and E. faecium bacteria isolated from naturally fermented Turkish white cheeses, produced without starter culture, against Listeria monocytogenes, L. innocua, L. ivanovii, Staphylococcus aureus, and E. faecalis were evaluated. The presence of entA and entB genes was also detected in the isolates, which had antimicrobial activity. Total 71 strains of E. faecalis and 7 strains of E. faecium were tested; 20 of E. faecalis and none of E. faecium strains showed antimicrobial activity against the tested bacteria using agar spot method. Among E. faecalis strains, which had antimicrobial activity, three strains contained both entA and entB genes, two strains carried only entA gene, and five strains had only entB gene. These cheese-sourced enterococcal strains or their enterocins should be considered to be used for food preservation especially in the dairy industry.

Quality of Life in Older Adults with Cochlear Implantation: Can It Be Equal to That of Healthy Older Adults?

Tokat Taskin,Müderris Togay,Bozkurt Ergul Basaran,Ergun Uğurtan,Aysel Abdulhalim,Catli Tolgahan 대한청각학회 2021 Journal of Audiology & Otology Vol.25 No.3

Background and Objectives: This study aimed to evaluate the audiologic results after cochlear implantation (CI) in older patients and the degree of improvement in their quality of life (QoL).Subjects and Methods: Patients over 65 years old who underwent CI at implant center in Bozyaka Training and Research Hospital were included in this study (n=54; 34 males and 20 females). The control group was patient over 65 years old with normal hearing (n=54; 34 males and 20 females). We administered three questionnaires [World Health Organization Quality of Life-BREF (WHOQOL-BREF), World Health Organization Quality of Life-OLD (WHOQOL-OLD)], and Geriatric Depression Scale (GDS) to evaluate the QoL, CIrelated effects on activities of daily life, and social activities in all the subjects. Moreover, correlations between speech recognition and the QoL scores were evaluated. The duration of implant use and comorbidities were also examined as potential factors affecting QoL.Results: The patients had remarkable improvements (the mean score of postoperative speech perception 75.7%) in speech perception after CI. The scores for the WHOQOL-OLD and WHOQOL-BREF questionnaire responses were similar in both the study and control groups, except those for a two subdomains (social relations and social participation). The patients with longer-term CI had higher scores than those with short-term CI use. In general, the changes in GDS scores were not significant (<i>p</i><0.05).Conclusions: The treatment of hearing loss with CI conferred significant improvement in patient’s QoL (p<0.01). The evaluation of QoL can provide multidimensional insights into a geriatric patient’s progress and, therefore, should be considered by audiologists.

Pathologic Evaluation of Routine Nasopharynx Punch Biopsy in the Adult Population: Is It Really Necessary?

Sami Bercin,Gokhan Yalciner,Togay Muderris,Fatih Gul,H. Mervan Deger,Muzaffer Kiris 대한이비인후과학회 2017 Clinical and Experimental Otorhinolaryngology Vol.10 No.3

Objectives. To retrospectively evaluate the patients who underwent nasopharyngeal biopsy with imaging and biopsy results, who have or don’t have symptoms for nasopharyngeal pathology and to determine the ratio of the nasopharyngeal cancer cases and other pathologic conditions. Methods. In this retrospective study, 983 patients who underwent endoscopic nasopharyngeal biopsy for symptomatic nasopharyngeal lesions were included. All pathological results, benign or malign was recorded and classified due to the patients’ presenting symptoms such as symptomatic for nasopharyngeal pathology or asymptomatic. Computed tomography (CT) or magnetic resonance imaging (MRI) reports were also recorded separately as group A for malignancy or group B for not malignancy. Results. Forty-five (4.6%) of 983 biopsies were malignant. In this group, there is no statistically significant difference between symptomatic and asymptomatic group. For malignant pathologies, the sensitivity of MRI was found 88.2% and CT was 61.5%. Conclusion. For early diagnosis of nasopharyngeal cancer, all patients admitted to Ear, Nose and Throat (ENT) referral clinics should be examined endoscopically irrespective of their complaints and suspicious cases should be investigated by imaging especially by MRI. If MRI report clearly indicates Thornwaldt cyst or reactive lymphoid hyperplasia and this result is compatible with endoscopic findings, biopsy may not be necessary. Apart from these cases, all suspected lesions should be biopsied.

Free vibration analysis of steel liquid storage tank with functionally graded column based on modified continuum mechanics

Cavus, Yakup Harun,Kupeli, Togay,Yayli, Mustafa Ozgur Techno-Press 2022 Coupled systems mechanics Vol.11 No.4

It's important to note that the number of studies on the lateral vibration of steel liquid storage tanks has been quite modest in the past. The aim of this research has to look at the variables that affect vibration of storage tanks and to highlight the characteristics of a construction that hasn't received much attention in the literature. The storage tank has pre-sized in the study, and aluminum and steel have chosen as components. The specified material qualities and the factors utilized in the investigation has used to calculate vibration frequency values. The resulting calculations are backed up by tables and graphs, and it's an important to look into the parameters that affect the vibration frequencies that will occur on the designed storage tank vary. In the literature, water tanks are usually modelled as lumped masses. The horizontal stiffness of the column on which it is placed is assumed to be constant throughout. This is an approximation method of solving this problem. The column is handled in this study with a more realistic approach that fits the continuum mechanics in the analysis. The reservoir part is incorporated directly into the problem as the boundary condition.

The effect of tensile reinforcement on the behavior of CFRP strengthened reinforced concrete beams: An experimental and analytical study

Javad Sabzi,M. Reza Esfahani,Togay Ozbakkaloglu,Ahmadreza Ramezani 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.46 No.1

The present study experimentally and analytically investigates the effect of tensile reinforcement ratio and arrangement on the behavior of FRP strengthened reinforced concrete (RC) beams. The experimental part of the program was comprised of 8 RC beams that were tested under four-point bending. Results have shown that by keeping the total cross-section area of tensile reinforcing bars constant, in specimens with a low reinforcement ratio, increasing the number and decreasing the diameter of bars in the section lead to 21% and 29% increase in the load-carrying capacity of specimens made with normal and high compressive strength, respectively. In specimens with high reinforcement ratio, a different behavior was observed. Furthermore, the accuracy of the existing code provisions and analytical models in predicting the load-carrying capacity of the FRP strengthened beams failed by premature debonding mode were evaluated. Herein, a model is proposed which considers the tensile reinforcement ratio (as opposed to code provisions) to achieve more accurate results for calculating the load carrying capacity of FRP strengthened RC beams.

High-velocity powder compaction: An experimental investigation, modelling, and optimization

Tohid Mirzababaie Mostofi,Mostafa Sayah-Badkhor,Mohammad Rezasefat,Hashem Babaei,Togay Ozbakkaloglu 국제구조공학회 2021 Structural Engineering and Mechanics, An Int'l Jou Vol.78 No.2

Dynamic compaction of Aluminum powder using gas detonation forming technique was investigated. The experiments were carried out on four different conditions of total pre-detonation pressure. The effects of the initial powder mass and grain particle size on the green density and strength of compacted specimens were investigated. The relationships between the mentioned powder design parameters and the final features of specimens were characterized using Response Surface Methodology (RSM). Artificial Neural Network (ANN) models using the Group Method of Data Handling (GMDH) algorithm were also developed to predict the green density and green strength of compacted specimens. Furthermore, the desirability function was employed for multi-objective optimization purposes. The obtained optimal solutions were verified with three new experiments and ANN models. The obtained experimental results corresponding to the best optimal setting with the desirability of 1 are 2714 kg·m-3 and 21.5 MPa for the green density and green strength, respectively, which are very close to the predicted values.

Concrete-steel bond-slip behavior of recycled concrete: Experimental investigation

Rui Ren,Liangjie Qi,Jian-yang Xue,Xin Zhang,Hui Ma,Xiguang Liu,Togay Ozbakkaloglu 국제구조공학회 2021 Steel and Composite Structures, An International J Vol.38 No.3

In order to study the interfacial bond-slip behavior of steel reinforced recycled concrete (SRRC) under cyclic loading, thirteen specimens were designed and tested under cyclic loading and one under monotonic loading. The test results indicated that the average bond strength of SRRC decreased with the increasing replacement ratio of recycled concrete, whereas the bond strength increased with an increase in the concrete cover thickness, the volumetric stirrup ratio, and the strength of recycled concrete. The ultimate bond strength of the cyclically-loaded specimen was significantly (41%) lower than that of the companion monotonically-loaded specimen. The cyclic phenomena also showed that SRRC specimens went through the non-slip phase, initial slip phase, failure phase, bond strength degradation phase and residual phase, with all specimens exhibiting basically the same shape of the bond-slip curve. Additionally, the paper presents the equations that were developed to calculate the characteristic bond strength of SRRC, which were verified based on experimental results.