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Article Citation - WoS: 20Citation - Scopus: 20Properties of the Pc(4312) pentaquark and its bottom partner(Iop Publishing Ltd, 2021) Azizi, K.; Sarac, Y.; Sundu, H.We present an analysis of the newly observed pentaquark P-c(4312)(+) to shed light on its quantum numbers. To do that, the QCD sum rules approach is used. The measured mass of this particle is close to the Sigma D-++(c)- threshold and has a small width, which supports the possibility of its being a molecular state. We consider an interpolating current in a molecular form and analyze both the positive and negative parity states with spin-. We also consider the bottom counterpart of the state with similar molecular form. Our mass result for the charm pentaquark state supports that the quantum numbers of the observed state are consistent with J(P) = 1/2(-).Article Citation - WoS: 32Citation - Scopus: 32Capacitance, Conductance, and Dielectric Characteristics of Al/Tio2< Diode(Springer, 2021) Gullu, H. H.; Yildiz, D. E.In this study, electrical properties of the Al/TiO2/p-Si diode structure with an atomic layer deposited TiO2 interface layer are investigated by current-voltage (I-V), capacitance-voltage (C - V), and conductance-voltage (G - V) measurements. It shows a rectifying behavior with about four order of rectification factor, and barrier height and ideality factor are calculated from the rectification curve. Dielectric parameters are determined from frequency-dependent C - V and G - V relations. The experimental results show that both of these curves are in a strong response to the frequency and bias voltage. They are found in decreasing behavior with increasing frequency, and both of them increase with increase in bias voltage although there are different increasing trends. At reversed bias voltage region, barrier potential, Fermi level energy, and interface charge carrier contribution are evaluated by using 1/C-2 - V plot. Series resistance values are also calculated under the variation of frequency and voltage. Thus, the capacitive characteristics of the diode are corrected by eliminating series resistance contribution together with the possible effect on interface charge carriers. Detailed information is obtained by determining electronic parameters affected by interface states over a wide frequency range (1 kHz to 1 MHz). At this point, strong response to the frequency is observed for the dielectric constant. Under the effect of interfacial polarization at low-frequency region, interface charge contribution to the capacitive response of the diode is obtained. Further analysis is performed on electrical modulus and impedance values derived from experimental dielectric data. Existence of interfacial layer capacitance is detailed by extracting distribution of interface charges from capacitance and conductance profiles of the diode under the effect of frequency.Article Citation - WoS: 7Citation - Scopus: 7Finite Element Analysis of Frames With Reinforced Concrete Encased Steel Composite Columns(Mdpi, 2022) Tunc, Gokhan; Othman, Mohammed Moatasem; Mertol, Halit CenanStructural frame systems that consists of concrete-encased-steel-embedded composite columns and reinforced concrete beams are typically used in mid-rise to tall buildings. In order to understand their overall structural behavior, a total of 12 frame models with high and low ductility features were constructed and analyzed using LS-DYNA software. Two of these models were validated using the results of previously tested frames. The remaining 10 models were studied to predict the behavior of frames with varying concrete strengths, reinforcement configurations, and structural steel sections under vertical and lateral loads. The results were investigated in terms of cracks and failure patterns, load-deflection relationships, energy dissipation, and stiffness degradation. The analytical results indicated that the high ductile frame models showed slightly better lateral load carrying performances compared to low ductility frame models. Moreover, the analytical studies demonstrated that the existence of structural steel in a column, regardless of its cross-sectional shape, was the most important parameter in improving the lateral load carrying capacity of a frame.Article Citation - WoS: 22Citation - Scopus: 36An Analysis of Course Characteristics, Learner Characteristics, and Certification Rates in MITx MOOCs(Athabasca Univ Press, 2020) Cagiltay, Nergiz Ercil; Cagiltay, Kursat; Celik, Berkan; Software EngineeringMassive Open Online Courses (MOOCs), capable of providing free (or low cost) courses for millions of learners anytime and anywhere, have gained the attention of researchers, educational institutions, and learners worldwide. Even though they provide several benefits, there are still some criticisms of MOOCs. For instance, MOOCs' high dropout rates or predominantly elite participation are considered to be important problems. In order to develop solutions for these problems, a deeper understanding of MOOCs is required. Today, despite the availability of several research studies about MOOCs, there is a shortage of in-depth research on course characteristics, learner characteristics, and predictors of certification rates. This study examined MOOC and learner characteristics in detail and explored the predictors of course certification rates based on data from 122 Massachusetts Institute of Technology MOOCs (MITx) on edX platform as well as data about the 2.8 million participants registered in these MOOCs. The results indicated that as the number of courses offered and the number of learners enrolled increased in years, there was a decrease in the certification rates among enrolled learners. According to our results, the number of average chapters completed, total forum messages, and mean age predicted course certification rates positively. On the other hand, the total number of chapters in a course predicted the course certification rates negatively. Based on these results, shorter and more interactive MOOCs are recommended by considering the needs of the learners, course content design, and strategies encouraging the enrolled students to enter the courses.Article Citation - WoS: 4Citation - Scopus: 5Experimental Investigation of Communication Performance of Drones Used for Autonomous Car Track Tests(Mdpi, 2021) Yildiz, Melih; Bilgic, Burcu; Kale, Utku; Rohacs, DanielAutonomous Vehicles (AVs) represent an emerging and disruptive technology that provides a great opportunity for future transport not only to have a positive social and environmental impact but also traffic safety. AV use in daily life has been extensively studied in the literature in various dimensions, however; it is time for AVs to go further which is another technological aspect of communication. Vehicle-to-Vehicle (V2V) technology is an emerging issue that is expected to be a mutual part of AVs and transportation safety in the near future. V2V is widely discussed by its deployment possibilities not only by means of communication, even to be used as an energy transfer medium. ZalaZONE Proving Ground is a 265-hectare high-tech test track for conventional, electric as well as connected, assisted, and automated vehicles. This paper investigates the use of drones for tracking the cars on the test track. The drones are planned to work as an uplink for the data collected by the onboard sensors of the car. The car is expected to communicate with the drone which is flying in coordination. For the communication 868 MHz is selected to be used between the car and the drone. The test is performed to simulate different flight altitudes of drones. The signal strength of the communication is analyzed, and a model is developed which can be used for the future planning of the test track applications.Article Polysulfur Copolymer as a Support Material for the Preparation of a Novel Multifunctional Photocatalytic Composite Material(Springer, 2025) Kesimal, Busra; Guner, Zuhal Vanli; Cihaner, Atilla; Kaya, MuratOne-step addition of magnetic nanoparticles and titanium dioxide nanoparticles into polysulfur copolymer as cheap and available support was reported for the first time to prepare the magnetically separable heterogeneous catalyst, PolyS-MNP-TiO2. The photocatalytic activities of the PolyS-MNP-TiO2 composite material and its constituents were examined in the methylene blue (MB) degradation, textile-based wastewater simulant, exposed to solar light. Detailed characterization of the catalysts was performed with SEM, TEM, and EDX measurements. The photocatalytic activity of the resulting composite was figured out in the removal of methylene blue dye by using a solar simulator. Significantly, the as-prepared PolyS-MNP-TiO2 exhibits exceptional photocatalytic activity and total degradation of dye molecules was achieved in 60 min. Additionally, the prepared novel photocatalyst showed enhanced stability and reusability due to the magnetic behavior of the composite material and the same portion of catalyst was used in five successive tries without apparent loss in catalytic activity by eliminating long and work-loaded processes like filtration and centrifugation.Article Citation - WoS: 13Citation - Scopus: 13Comparison of Physicochemical Properties of Two Types of Polyepichlorohydrin-Based Anion Exchange Membranes for Reverse Electrodialysis(Mdpi, 2022) Karakoc, Ezgi; Guler, EnverThe development of the most effective, suitable and economic ion-exchange membranes is crucial for reverse electrodialysis (RED)-the most widely studied process to harvest salinity gradient energy from mixing seawater and river water. RED utilizes two types of membranes as core elements, namely cation exchange membranes (CEM) and anion exchange membranes (AEM). Since the preparation of AEMs is more complex compared to CEMs, the design and development of anion exchange membranes have been the focus in this study. Homogeneous AEMs based on two types of polyepichlorohydrin (PECH) with different chlorine amounts (PECH-H, 37 wt% and PECH-C, 25 wt%) were synthesized, and first-time benchmarking of the membrane properties was conducted. In addition to physicochemical membrane properties, some instrumental analyses such as SEM, FTIR and DSC were investigated to characterize these anion-exchange membranes. Based on the results, although the PECH-H-type membrane had enhanced ion-exchange properties, PECH-C-based anion-exchange membranes exhibited a higher power density of 0.316 W/m(2) in a lab-scale RED system. Evidently, there is room for the development of new types of PECH-C-based AEMs with great potential for energy generation in the RED process.Article Citation - WoS: 34Social Jetlag Is Associated With the Frequency of Consumption of Sugar-Sweetened Beverages and a High Bmi Percentile in Adolescents: Results of the Cross-Sectional Family Life, Activity, Sun, Health, and Eating (flashe) Study(Elsevier Science inc, 2021) Cetiner, Ozlem; Yildirim, Gonca; Kalyoncu, Zeynep BegumBackground Social jetlag (SJL) occurs in adolescents due to misalignment of the bio-logical and social clocks, so that most teens wake up earlier than their biological clocks on weekdays and delay bedtime and wake up time on weekends. This shift in sleep timing among adolescents is associated with an adverse endocrine and behavioral risk profile, in addition to increased food consumption and increased body mass index (BMI). Objective The aim of this study was to determine the association between SJL, and the frequency of consumption of multiple food and beverage groups and BMI percentile in adolescents. Design Publicly available data from the cross-sectional Family Life, Activity, Sun, Health, and Eating (FLASHE) study were analyzed. Participants Participants from the FLASHE study were recruited from all regions of the United States between April and October 2014. Among the 1,581 adolescents aged 12 through 17 years in the original study, 1,556 with complete sleep data were analyzed. Main outcome measures The difference between the frequency of dietary consump-tion according to the Dietary Screener Questionnaire and BMI percentile was assessed in adolescents grouped according to SJL, as follows: no SJL: less than 1-hour difference; mild SJL: 1-to 2-hour difference; and severe SJL: more than 2-hour difference. Statistical analyses performed Differences in the frequency of food consumption were analyzed using the Kruskal-Wallis test. Secondary outcomes were analyzed using logistic regression models. Results Daily consumption frequency of sugar-sweetened beverages and fruits and vegetables differed among the 3 groups. Likewise, the BMI percentile differed among the 3 groups and was highest in the severe SJL group. Those in the severe SJL group had a 1.84-fold higher probability of having overweight or obesity (95% CI 1.83 to 1.84) than those in the no SJL group. Conclusions Severe SJL is associated with a higher frequency of sugar-sweetened beverage consumption and higher odds of having overweight or obesity compared with no SJL in adolescents. J Acad Nutr Diet. 2021;121(9):1721-1731.Article Citation - WoS: 3Citation - Scopus: 6Outcomes of Pain Management Among Postoperative Patients: a Cross-Sectional Study(Elsevier Science inc, 2024) Akire, Sandra Chirota; Bayraktar, NurhanPurpose: Postoperative pain management has always been a significant challenge for both hospital staff and surgical patients. Determination of pain management outcomes among surgically treated patients may help develop pain management strategies, improve health services that would yield better outcomes, and increase patient satisfaction. This study aimed to assess the outcomes of pain management among postoperative patients. Design: The study was a descriptive cross-sectional study. Methods: The research was performed on postoperative patients at two university hospitals in North Cyprus from July to September 2019. The study sample consisted of 90 patients from both hospitals. The Turkish Version of the revised American Pain Society Patient Outcome Questionnaire (APS-POQ-R-TR) was used for data collection. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist was used to report the present study. Findings: This study showed that the overall mean for pain severity and the worst pain experienced by patients after 24 hours was slightly higher than medium. Examination of interference of the pain with functions demonstrated that patients experienced problems with physical activities and sleeping. The most experienced side effects were nausea and drowsiness, and the most common emotions were anxiety and helplessness during the postsurgery period. The satisfaction rate of the patients with postoperative pain management was relatively high. Conclusions: A holistic approach with evidence-based practices is crucial for adequate postoperative pain management. The recommendations include the development of individual pain outcome strategies to improve overall satisfaction with pain management among postoperative patients. (c) 2024 American Society of PeriAnesthesia Nurses. Published by Elsevier Inc. All rights reserved.Article Citation - Scopus: 1The Relationship Between Soong Classification and Fracture Characteristics with Implant Removal for Distal Radius Fractures: A Comparative Study of 795 Cases(Elsevier Masson, Corp Off, 2025) Yogun, Yener; Bezirgan, Ugur; Ertan, Mehmet Batu; Gezer, Mehmet Can; Armangil, MehmetIntroduction: Although there is no consensus in the literature, it is believed that the Soong classification system and fracture pattern are risk factors for plate removal in distal radius fractures. Hypothesis: The aim of this large-scale study was to evaluate the relationship between Soong classification, fracture pattern, and implant removal in distal radius fractures. Materials and methods: We retrospectively evaluated 795 patients who underwent surgery using a volar locking plate for distal radius fractures at our clinic between 2005 and 2022. The patients were divided into two groups: implant removed, and implant retained. The groups were examined for demographic data, follow-up periods, fracture classifications, and radiological parameters. Additionally, the patients were divided into groups and compared according to the Soong classification, which was determined according to implant placement. Indications for implant removal were also included in this study, and their relationships with other parameters were evaluated. Results: A total of 123 and 672 patients were included in the implant removed and retained groups, respectively. The average age of the implant removed group was significantly lower (p = 0.005). There were no significant differences between the two groups in terms of fracture classification or other radiological parameters. In the implant removed group, the rate of grade 2, according to the Soong classification, was statistically higher than that in the other groups (p = 0.019). Flexor tenosynovitis was the most common reason for implant removal. Conclusion: The Soong classification system is an important risk factor associated with implant removal. This risk may increase, particularly among young patients. Surgeons should consider placing the distal radius locking plate as proximally as possible to reduce the frequency of implant removal. Level of evidence: III; retrospective comparative study
