Kırşehir Ahi Evran University Institutional Repository
Not a member yet
6557 research outputs found
Sort by
First Record Of Endosymbiotic Wolbachia In The Remarkably Diverse Tribe Dorcadionini (Coleoptera: Cerambycidae)
No full textSpecies diversity is remarkable especially in Dorcadion genus, which spreads in Europe and the Caucasus. Most members of the genus are incapable of flight, generally isolated, and some are endemic. Therefore, there are many studies on the distribution and diversity of species of Dorcadion. However, there is no study on endosymbiotic bacteria that play a critical role in the ecology, physiology and evolution of arthropods. In this study, endosymbiotic Wolbachia bacteria were investigated in members of D. crux Bilberg, 1817, D. micans micans Thomson, 1867, D. anatolicum Pic, 1900, D. septemlineatum Waltl, 1838 and D. scabricolle Dalman, 1817, collected from six different localities. Studies were performed with the Wspec-F/R primer pair. Two of the five examined species of Dorcadion (D. septemlineatum and D. micans micans) are not infected by Wolbachia. On the other hand, Wolbachia (supergroup B type) with the same consensus sequence was detected in D. anatolicum, D. scabricolle and D. crux. Interestingly, Wolbachia, which was thought to be accidental, was found to be common in males, but unfortunately this could not be explained by the data set obtained. However, considering the variations in Dorcadion species and the evaluations according to them, it can be claimed that there is no ordinary association between this taxon and Wolbachia. We hypothesize that among the possible explanations for the large morphological variability in Dorcadionini is the influence of the maternally inherited endosymbiotic Wolbachia. Therefore, we believe that the data obtained in this manuscript will contribute to studies on Dorcadion diversity and distribution
Investigation of the Effect of Climate Change on Extreme Precipitation: Capital Ankara Case
Get PDFThis study examines the potential impacts of climate change on extreme precipitation. Rainfall analysis with stationary and nonstationary approach for observed and future conditions is performed for (1950-2015 period) observed data of 5, 10, 15, 30 minutes and 1, 2, 3, 6 hour and projections (2015-2098 period) of 10, 15 minutes and 1, 6 hour for Ankara province, Turkey. Daily projections are disaggregated to finer scales, 5 minutes storm durations, then five minutes time series aggregated to the storm durations that are subject of interest. Nonstationary Generalized Extreme Value (GEV) models and stationary GEV models for observed and future data are obtained. Nonstationary model results are in general exhibited smaller return level values with respect to stationary model results of each storm duration for observed data driven model results. Considering the projected data driven model results; on average nonstationary models produce mostly lower return levels for mid and longer return periods for all storm durations and return periods except one hour storm duration. Depending on the models and Representative Concentration Pathways (RCP), there are different results for the future extreme rainfall input; yet all results indicate a decreasing extreme trend
Sequential Transient Detection for RF Fingerprinting
Get PDFIn this paper, a sequential transient detection method for radio frequency (RF) fingerprinting used in the identification of wireless devices is proposed. To the best knowledge of the authors, sequential detection of transient signals for RF fingerprinting has not been considered in the literature. The proposed method is based on an approximate implementation of the generalized likelihood ratio algorithm. The method can be implemented online in a recursive manner with low computational and memory requirements. The transients of wireless transmitters are detected by using the likelihood ratio of the observations without the requirement of any a priori knowledge about the transmitted signals. The performance of the method was evaluated using experimental data collected from 16 Wi-Fi transmitters and compared to those of two existing methods. The experimental test results showed that the proposed method can be used to detect the transient signals with a low detection delay. Our proposed method estimates transient starting points 20-times faster compared to an existing robust method, as well as providing a classification performance of a mean accuracy close to 95%
Effect of the COVID-19 Pandemic on Radical Prostatectomy: A Turkish Multicenter Study
Get PDFObjective: The present study examines the effects of the coronavirus disease 2019 pandemic on radical prostatectomy performed as part of localized prostate cancer treatment in Turkey. Material and methods: A retrospective analysis was made of the data of 176 patients from 8 centers in Turkey who underwent radical prostatectomy due to localized prostate cancer over the 2 years spanning March 1, 2019, to February 28, 2021. Within this timeframe, March 1, 2019, to February 28, 2020, was denoted the 1-year pre-coronavirus disease 2019 period, while March 1, 2020, to February 28, 2021, was denoted the 1-year coronavirus disease 2019 period. An analysis was made of whether there was a difference in the number of radical prostatectomies performed for prostate cancer, the time from biopsy to operation, and the biopsy and radical prostatectomy pathology between the 2 periods. Results: It was found that the number of radical prostatectomies performed for localized prostate cancer during the coronavirus disease 2019 pandemic was statistically and highly significantly fewer than in the pre-coronavirus disease 2019 period (P < .001). The patients diagnosed with Gleason 3 + 3 (low risk) prostate cancer were statistically significantly fewer in number in the coronavirus disease 2019 period (P < .001). The pathological Gleason score was upgrading than the biopsy Gleason score in all patients who underwent in both periods (P < .001). When the periods were compared, the pathological involvement determined by lymph node dissection performed during radical prostatectomy was found to be decreased in the coronavirus disease 2019 period, although the difference was not statistically significant (P = .051). Conclusion: As with many diseases, the diagnosis and treatment of prostate cancer have been adversely affected by the coronavirus disease 2019 pandemic. © 2022, AVES. All rights reserved
Astragalus oksutdagensis (Fabaceae), a new species from Turkey
Get PDFThis study describes the new species Astragalus oksutdagensis (A. sect. Eustales) from Kayseri, Turkey. The species is compared morphologically to the two similar species A. flavescens and A. vestitus, considering also pollen micromorphology. The geographical distribution of A. oksutdagensis, A. vestitus and A. flavescens is mapped. The phylogenetic relationships between the new species and other closely related species in the genus are inferred based on DNA data from the internal transcribed spacer regions (ITS) and it is shown that A. sect. Eustales is monophyletic but closely related to A. sect. Tragacantha. The new species is assessed as critically endangered (CR) following the IUCN Red List Categories and Criteria. © 2021 Nordic Society Oikos. Published by John Wiley & Sons Ltd
Highway accident number estimation in Turkey with Jaya algorithm
Get PDFIn the transportation sector in Turkey, approximately 90% of cargo and passenger transportation is carried out on highways. In recent years, increasing population and welfare levels have brought along an increase in demand for and intensity of highway use. Accidents experienced along with the increased intensity in the use of highways result in fatalities and loss of property. In order to minimize such losses on the highways and determine plans and programs for the future by benefiting from historical data, it is necessary to conduct accurate, consistent, effective, and reliable accident estimations. In the study, highway accident number estimation (HANE) in Turkey was made by using the meta-heuristic Jaya optimization algorithm. For HANE, Jaya linear (Jaya-L) and Jaya Quadratic (Jaya-Q) models were proposed. Indicators such as the number of accidents that occurred between 2002 and 2018, population, gross domestic product (GDP), total divided road length (TDRL), and the number of vehicles were taken for HANE. Indicators were analyzed for four different conditions. HANE was made by using Population–GDP–TDRL–Number of Vehicle indicators together. A total of 75% of the total 17-year data between 2002 and 2018 were used for training purposes, and 25% of the data were used for testing. The results of the proposed Jaya-L and Jaya-Q models were analyzed by comparing them with the Andreassen estimation model (AEM) and multiple linear regression (MLR) methods. Following the successful training and testing results, low, expected, and high scenarios were proposed, and the number of accidents between 2019 and 2030 was estimated. © 2022, The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature
Dual-Band Patch Antenna with Simple Rectangular Shaped Slots for Local Area Networks
Get PDFIn this study, a coplanar waveguide fed patch antenna is proposed for Wireless Local Area Network (WLAN) and Worldwide Interoperability for Microwave Access (WiMAX) operations. To obtain multiband functionality and tune the frequencies rectangular shaped slots are embedded vertically and horizontally on the radiating part. The effects of the slots on the operating frequencies are analyzed in detail by performing parametric analyzes. The proposed antenna operates in a wide range covering WLAN and WiMAX frequencies between 2.38 and 5.46 GHz. To authenticate the simulation results an example model is manufactured using a 40 × 30 mm2 FR4 dielectric substrate with the permittivity of 4.3. It has been obtained a good compatibility between the computer software results and measurment results. The measurement shows that the antenna can provide dual impedance bandwidths by having resonances at 2.74 GHz and 4.94 GHz. Consequently, the final antenna model is a good candidate to be used at the designed frequencies and one can have a clear idea how to control the resonant frequencies of the antenna for different dimension parameters of the slots. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature
Molecular typing of MDR-K. pneumoniae using ERIC-PCR Technique
No full textKlebsiella pneumoniae is a Gram-negative bacterium that exists naturally in the human body's gastrointestinal tract as part of the natural microflora. It has long been recognized as one of the most frequent nosocomial diseases and a multidrug resistant pathogen. The purpose of the current work was to determine the antimicrobial susceptibility and genetic relatedness of K. pneumoniae strains obtained from Ramadi hospitals, western Iraq, using the ERIC–PCR approach. In the period between June and September 2021, 51 K. pneumonia isolates were obtained from Anbar hospitals. After normal laboratory procedures and differential assays identified K. pneumoniae isolates, disk diffusion susceptibility testing was performed. Also, ERIC-PCR was used to determine genetic relatedness of 15 MDR K. pneumoniae isolates. Kirby –bauer disk diffusion test showed that among K. pneumonia isolates, the highest antibiotic resistance was to Augmentin (96%), cefotaxime (92%), ceftriaxone =Ceftazidime (88%), Amikacin (48%), Levofloxaccin (42%), and imipenem (26%). More than 66.66% of the isolates revealed multi-drug resistant phenotypes. ERIC-PCR results and data analysis indicate that there are 23 distinct ERIC types. The findings of this study show an increase in the prevalence of multiresistant K. pneumoniae in the hospitals studied. The ERIC PCR results revealed a high level of genetic diversity across K. pneumoniae strains, showing that K. pneumoniae isolates are polyclonal in Anbar hospitals. © RJPT All right reserved
Experımental Determınatıon Of Bıofılm And Mechanıcal Propertıes Of Surfaces Obtaıned By Co2 Laser Gas-Assısted Nıtrıdıng Of Ti-6al-4v Alloy
No full textThe nitriding process is a surface treatment that improves the surface properties of titanium alloys and increases wear/corrosion resistance. This study investigates the structural and mechanical property changes in titanium alloy after nitriding. Micro-hardness differences between the nitrided and non-nitrided surface and morphological changes on the surface were determined. In addition to evaluating the effect of vanadium and aluminum ions on the nonnitrided surface, the impact of nitrided and non-nitrided surfaces on biofilm layer formation was investigated. It was determined that the TiN layer formed on the nitrided surface showed superior properties to its non-nitrided surface in the biofilm tests performed for 6 h. As a result of the tensile tests, it can be said that the nitriding process increases the elasticity module of the Ti-6Al-4V alloy and provides the material to have a more rigid structure. It was also analyzed using finite element analysis (FEA) of mechanical behaviors of the test sample under the tension loads
Finite Element Analyses of a TLA-type Synchronus Reluctance Machine
Get PDFAbstract— Generating energy efficient and eco-friendly electrical machines has been recently focused by researchers
due to rapid decline in energy sources and increase in greenhouse gas effect. Since Inductance Machines have some
drawbacks: low torque capability, low efficiency hence high energy consumption, and high carbon dioxide emission,
designing Synchronous Reluctance Machines is crucial to overcome these drawbacks of Inductance Machines.
Synchronous Reluctance Machines have attractive features: higher torque capability, enhanced efficiency, reduced
greenhouse gas emission, longer lifetime and maintenance period comparing with Inductance Machines. In this study, flux
barrier number, shape of flux barriers and rotor position effects on machine’s performance is carried out by Finite Element
Analyses. The analyses has concluded that the hyperbolic shaped machine with four barriers is the optimum design
considering performance parameters and rotor position considerably affects torque, saliency ratio, power factor and
efficiency of machines