Scopus Kapalı Erişimli Yayınlar

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    The Role of Nutritional and Dietary Habits in Etiology in Pediatric Vocal Fold Nodule
    (2022) Korkmaz, Muge Ozcelik; Tuzuner, Arzu
    Objectives. In pediatric pediatric vocal fold nodule (VFN) patients, different causes have been suggested in the development of the vocal cord nodule, including laryngopharyngeal reflux (LPR). It is known that the content of consumed foods, obesity, and other dietary behaviors are among the risk factors for the devel-opment of reflux. The aim of this study was to evaluate dietary and food consumption habits in pediatric VFN patients.Methods. This prospective-controlled study included 50 children with VFNs (age range 5-14 years) and 50 age-matched children without any voice disorders as a control group. BMI values of each participant were evaluated according to age-percentile range. The voice usage habits and personality structure of all the children were ques-tioned. All patients underwent laryngeal examination and voice analysis. The Turkish Pediatric Voice Handicap Index (t-PVHI) and Child Voice Handicap Index-10 (t-CVHI) were completed by patients or their parents. The examination findings of all patients were evaluated with the reflux finding score (RFS), and their complaints were questioned with the reflux symptom index (RSI). In addition, eating and drinking at night, fast eating and exces -sive food consumption habits and the frequency of consumption of packaged foods defined as junk food, carbon-ated beverage were questioned. The data obtained were compared statistically between the two groups.Results. There was no significant difference between the study and control groups in terms of age, gender distri-bution, median BMI value, voice usage habits, and personality structure. In the study group, t-PVHI, t-CVHI, jit-ter, schimmer values, the mean RFS, and RSI scores were significantly higher than those of the control group. The number of children with high consumption of junk food and carbonated drinks was higher in the study group. There was no significant difference between the two groups in terms of dietary habits.Conclusion. Food consumption habits may play a role in childhood voice problems in this population.
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    A Tabu Search Algorithm for the Training of Neural Networks
    (2009) Dengiz, B.; Alabas-Uslu, C.; Dengiz, O.
    The most widely used training algorithm of neural networks (NNs) is back propagation ( BP), a gradient-based technique that requires significant computational effort. Metaheuristic search techniques such as genetic algorithms, tabu search (TS) and simulated annealing have been recently used to cope with major shortcomings of BP such as the tendency to converge to a local optimal and a slow convergence rate. In this paper, an efficient TS algorithm employing different strategies to provide a balance between intensification and diversification is proposed for the training of NNs. The proposed algorithm is compared with other metaheuristic techniques found in literature using published test problems, and found to outperform them in the majority of the test cases.
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    A Self-tuning Heuristic for the Design of Communication Networks
    (2015) Dengiz, Berna; Alabas-Uslu, Cigdem
    This paper addresses the design of communication networks that has a large application area. The problem is to design a minimum cost network subject to a given reliability level. Complexity of the problem is twofold: (1) finding a minimum-cost network topology that every pair of nodes can communicate with each other and (2) computing overall reliability to provide the reliability constraint. Over the last two decades, metahemistic algorithms have been widely applied to solve this problem due to its NP-hardness. In this study, a self-tuning heuristic (STH), which is a new approach free from parameter tuning, is applied to the design of communication networks. Extensive computational results confirm that STH generates superior solutions to the problem in comparison to some well-known local search metaheuristics, and also more sophisticated metaheuristics proposed in the literature. The practical advantage of STH lies in both its effectiveness and simplicity in application to the design problem.
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    A Self-adaptive Local Search Algorithm for the Classical Vehicle Routing Problem
    (2011) Alabas-Uslu, Cigdem; Dengiz, Berna
    The purpose of this study is introduction of a local search heuristic free from parameter tuning to solve classical vehicle routing problem (VRP). The VRP can be described as the problem of designing optimal delivery of routes from one depot to a number of customers under the limitations of side constraints to minimize the total traveling cost. The importance of this problem comes from practical as well as theoretical point of view. The proposed heuristic, self-adaptive local search (SALS), has one generic parameter which is learnt throughout the search process. Computational experiments confirm that SALS gives high qualified solutions to the VRP and ensures at least an average performance, in terms of efficiency and effectiveness, on the problem when compared with the recent and sophisticated approaches from the literature. The most important advantage of the proposed heuristic is the application convenience for the end-users. SALS also is flexible that can be easily applied to variations of VRP. (C) 2011 Elsevier Ltd. All rights reserved.
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    A General Neural Network Model for Estimating Telecommunications Network Reliability
    (2009) Altiparmak, Fulya; Dengiz, Berna; Smith, Alice E.; 0000-0003-1730-4214; 0000-0001-8808-0663; AAF-7020-2021; AAK-2318-2021
    This paper puts forth a new encoding method for using neural network models to estimate the reliability of telecommunications networks with identical link reliabilities. Neural estimation is computationally speedy, and can be used during network design optimization by an iterative algorithm such as tabu search, or simulated annealing. Two significant drawbacks of previous approaches to using neural networks to model system reliability are the long vector length of the inputs required to represent the network link architecture, and the specificity of the neural network model to a certain system size. Our encoding method overcomes both of these drawbacks with a compact, general set of inputs that adequately describe the likely network reliability. We computationally demonstrate both the precision of the neural network estimate of reliability, and the ability of the neural network model to generalize to a variety of network sizes, including application to three actual large scale communications networks.
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    A cross entropy approach to design of reliable networks
    (2009) Dengiz, Berna; Altiparmak, Fulya; 0000-0003-1730-4214; AAF-7020-2021
    One of the most important parameters determining the performance of communication networks is network reliability. The network reliability strongly depends on not only topological layout of the communication networks but also reliability and availability of the communication facilities. The selection of optimal network topology is an NP-hard problem so that computation time of enumeration-based methods grows exponentially with network size. This paper presents a new solution approach based on cross-entropy method, called NCE, to design of communication networks. The design problem is to find a network topology with minimum cost such that all-terminal reliability is not less than a given level of reliability. To investigate the effectiveness of the proposed NCE, comparisons with other heuristic approaches given in the literature for the design problem are carried out in a three-stage experimental study. Computational results show that NCE is an effective heuristic approach to design of reliable networks. (C) 2008 Elsevier B.V. All rights reserved.
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    Comparison Of Clinical Characteristics Of Second And Third Peaks Of COVID-19 Pandemic: Effects Of Vaccination And Preventive Measures
    (2022) Ozdemir, Ozer; Arslan, Atakan; Bulbul, Hande M.; Ozdemir, Pelin
    BACKGROUND: Understanding the differences in consequent peaks of COVID-19 may guide us for better predicting future disease characteristics. In this study, we aimed to compare clinical and radiological characteristics as well as out-comes of hospitalized patients with the diagnosis of COVID-19 in second and third peaks of disease.METHODS: We retrospectively included 303 hospitalized patients with COVID-19. The study population was examined in two groups: patients hospitalized between October 2020 and January 2021 during second peak and patients hospital-ized between March and June 2021 during third peak.RESULTS: There were 171 patients in group 1 and 132 patients in group 2. The patients in group 2 were younger (64 +/- 13.27 vs. 56.02 +/- 15.39, respectively; P<0.001) and female proportion was higher (64.9% and 48.5% males; P=0.005). Smoking history and presence of comorbidities were less in group 2 (41.5% vs. 25.7%, P=0.008; and 78.5% vs. 59.1%, P<0.001) and symptom duration was shorter (median 7 days vs. 6 days, P=0.039). CT severity scores, LDH, CRP, D-di-mer, Ferritin, and creatinine levels were lower in group 2 (P=0.003, P=0.008, P<0.001, P<0.001, P<0.001, respectively), and mortality ratio was lower (N.=39 [28%] vs. N.=15 [11.4%], P=0.01). Duration of hospital stay and need for intensive unit care were similar across groups (median 8 days vs. 7 days, P=0.673 and N.=39 [22.8%] vs. N.=33 [25.2%], P=0.683).CONCLUSIONS: Although duration of hospital stay was lower in third peak, clinical severity scores and prognostic markers were lower compared with second peak. These may reflect the increased proportion of immunized people, and the effect of preventive measures.
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    Development of Electrochemical Biosensor Platforms for Determination of Environmental Viral Structures
    (2022) Ekici, Rumeysa; Bozdogan, Betul; Denkbas, Emir Baki
    Infectious diseases caused by viruses (such as influenza, Zika, human immunodeficiency, Ebola, dengue, hepatitis, and COVID-19 virus) are diseases that have been on the agenda of the whole world for the last quarter of a century and have become one of the most important problems for people. Urgent identification of the people infected with a disease will allow these people who have contracted the disease to be treated effectively. In this context, the polymerase-chain-reaction (PCR)-based methods have been the most common and widely used method that responds with sensitivity. However, due to some disadvantages encountered in PCR applications (in particular, the test protocol is comprehensive, not fast in terms of time, not economical, requires user expertise, is not suitable for field/on-site measurements, etc.), a new generation (which can give fast results, are economical, sensitive, suitable for on-site application, etc.) of systems that can provide solutions are needed. On the subject of different test-diagnostic applications used in a large number of test-based analysis methods and techniques, electroanalytical systems have some advantages. Within the scope of this presentation, low-cost, miniaturized electrochemical platforms for surface-printed electrodes by using appropriate biochemical and viral structures of the electrode surfaces decorated with suitable agents are explained. These platforms can be used in the determination of some particular viral proteins for the understanding of viral pathogenic diseases. In this study, a copper-modified graphite electrode was developed and characterized with SEM. Afterwards, an antibody of the N protein of COVID-19 was decorated surrounding this electrode to measure the amount of that protein in the samples. The square wave voltammetry (SWV) technique was used for the electrochemical detection of SARS-CoV-2. When the results of the analyses were examined, the best analytical sensitivity and linearity were obtained by incubating the antibody-modified electrode and virus antigen for 10 min. The measurements showed linearity with a high correlation coefficient (R-2 = 0.9917). The detection limit (LOD) was calculated as 508 pg/mL. The measurement limit (LOQ) was calculated as 1.54 ng/mL. With the pencil tip, which is an easily accessible material for the modified electrode system we designed, a very precise measurement was provided for the rapid detection of the N protein of the SARS-CoV-2 virus at very low concentrations.
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    Pediatric T-cell Lymphoblastic Leukemia/Lymphoma Diagnosed at Routine Adenoidectomy Specimen
    (2023) Kara, Iike; Ramadan, Saime; Senkal, Evrim; Kocdor, Pelin; 36476077
    Postoperative routine pathologic evaluation of tonsillectomy and adenoidectomy specimens rarely reveals a diagnosis of malignancy. The object of this case report is to highlight this rare clinical occurrence. A 4-year-old boy presented with symptoms of sleep-disordered breathing and had a history of recurrent tonsillitis. Physical examination revealed adenoid hypertrophy and Brodsky Grade 1 bilateral tonsillar hypertrophy. The patient underwent adenoidectomy and tonsillectomy. The adenoids were found to be MAGS Grade 4 (Modified Adenoid Grading System) hypertrophic causing 100% obstruction. After the histologic examination, T-cell lymphoblastic leukemia/lymphoma was diagnosed. Proper treatment allowed full recovery. Currently, no consensus has been made about routine pathological evaluation. To achieve a cost-effective and precautionary approach, we recommend pathological follow-up of cases with unusual intraoperative findings with/without clinical malignancy suspicion.
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    Clinical Effectiveness Of Buccally And Palatally Anchored Maxillary Molar Distalization: The Miniscrew-Supported 3-Dimensional Maxillary Bimetric Distalizing Arch Vs The Beneslider
    (2022) Tuncer, Nilufer Irem; Arman-Ozcirpici, Ayca; 36457217
    Introduction: This study aimed to investigate the dentoalveolar and skeletal changes achieved with a novel miniscrew-supported 3-dimensional maxillary bimetric distalizing arch (3D-MBDA) and the Beneslider. In addition, the study aimed to compare these changes between each other and with an untreated control group. Methods: Sixty-five patients with bilateral Class II molar relationship and fully-erupted maxillary second molars were included in the study. Of these patients, 23 received the miniscrew-supported 3D-MBDA (group 1), 21 received the Beneslider (group 2), and 21 served as untreated control subjects (group 3). Lateral cephalometric films and dental casts, taken at the beginning and the end of maxillary molar distalization, were analyzed to study the differences between the groups. Results: The crown distalization of the first molars was similar between the treatment groups (group 1, 3.1 mm; group 2, 3.3 mm); however, root distalization was significantly more in group 1 (5 mm) when compared with group 2 (1.7 mm). The first molars tipped 6.2 degrees in the mesial direction in group 1 and 8.2 degrees in the distal direction in group 2. The mesiobuccal cusp tip of the first molars extruded for 1.2 mm and increased vertical dimensions in group 2, whereas it intruded for 1.7 mm in group 1. Meanwhile, aforementioned parameters presented insignificant changes throughout the observation period in the control group. Inter-first molar width increased significantly in group 2 (2.7 mm). Distalization time was similar between the groups (group 1, 14 months; group 2, 15 months). The distalization rate was higher in group 2 (0.27 mm/mo) than in group 1 (0.23 mm/mo) measured from the crowns; however, it was similar between the groups (group 1, 0.25 mm/mo; group 2, 0.19 mm/mo) when measured from the trifurcation point. Conclusions: The miniscrew-supported 3D-MBDA was more effective in distalizing molar roots and maintaining vertical parameters and dental arch width while tipping the molars mesially. In contrast, the Beneslider distalized molar crowns faster, resulting in significant distal tipping. (Am J Orthod Dentofacial Orthop 2022;162:e337-e348)