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Öğe A New Breakthrough Detection Method for Bone Drilling in Robotic Orthopedic Surgery with Closed-Loop Control Approach(Springer, 2020) Torun, Yunis; Ozturk, AhmetBreakthrough detection is a crucial task to reduce the risks of damaging soft tissue bone drilling operations during orthopedic surgery. Conventional drills are not equipped with this function while the recent literature has offered this capability with high cost and complex modification needs. In this study, a new breakthrough detection approach based on closed-loop control characteristics of the drilling operation is proposed. A feature set containing closed-loop signals and force sensor data is created to train K-Nearest and Ensemble Classifier for breakthrough detection tasks with drilling the synthetic bone model and animal bone with a robot manipulator. The best accuracy of breakthrough detection with only closed-loop control signal attributes is achieved as 96.9 +/- 0.8% for the synthetic bone model and 98.1 +/- 0.2% for sheep femur bone. Breakthrough detection delay which included sampling and operation time of the method guarantees that the drill bit would stop with acceptable breakthrough range of 1.0413 mm. The proposed method can be used to detect breakthrough and also to estimate the state of the drill bit in robotic orthopedic bone drilling processes using only closed-loop signals so that it would be no need to use extra high-cost sensors.Öğe AMINOETHOXYVINYLGLYCINE AND FOLIAR ZINC TREATMENTS PLAY A KEY ROLE IN PRE-HARVEST DROPS AND FRUIT QUALITY ATTRIBUTES OF 'WILLIAM'S PRIDE' APPLE(WYDAWNICTWO AKAD ROLNICZEJ W LUBLINIE, 2019) Ozturk, Burhan; Yildiz, Kenan; Erdem, Halil; Karakaya, Orhan; Ozturk, Ahmet; Aglar, ErdalEffects of pre-harvest aminoethoxyvinylglycine (AVG, 250 mg L-1) and zinc (0.3% ZnSO4) treatments on pre-harvest fruit drops, internal ethylene concentration (IEC), flesh firmness, color characteristics (L*, chroma and hue angle), soluble solids content (SSC), acidity, total phenolics, antioxidant activity, flesh and leaf micronutrients and macronutrients of 'William's Pride' apples, were investigated in this study. AVG was sprayed 4 weeks before the anticipated harvest date and Zn was sprayed when the fruits reached the size of a walnut. As compared to the control, both the single AVG and zinc treatments significantly reduced the pre-harvest drops. However, combined AVG + Zinc treatments were found to be more effective in reducing the pre-harvest drops. At the last measurement date (15th of August), 60% fruit drop was measured in control, but 22% in AVG + Zinc treatment. AVG and AVG + Zinc treatments reduced ethylene synthesis. On the other hand, single zinc treatments stimulated ethylene synthesis. AVG treatments retarded red skin color development, but zinc treatments again stimulated red color development. As compared to the control and single zinc treatments, AVG-treated fruits had greater firmness and acidity values, but lower SSC values. While AVG treatments increased the total phenolics and antioxidant activity, zinc treatments decreased these attributes. As compared to the control, zinc treatments significantly increased flesh Cu, N, P and K contents and leaf Mn, N and P contents. Based on present findings, it was concluded that AVG could be used as an efficient tool to reduce the pre-harvest drops in apples.Öğe Clinical efficacy of low dose flutamide plus diane-35 in the treatment of idiopathic hirsutism and polycystic ovary syndrome(Via Medica, 2013) Boztosun, Abdullah; Açmaz, Gökhan; Ozturk, Ahmet; Müderris, Iptisam IpekObjective: Idiopathic hirsutism (IH) or polycystic ovary syndrome (PCOS) are the most common causes of hirsutism which affects 5-10 % of all women. The aim of this study was to evaluate the efficacy of flutamide plus diane 35 in the treatment of idiopathic hirsutism and polycystic ovary syndrome. Materials and Methods: 26 polycystic ovary syndrome and 24 idiopathic hirsutism patients wereevaluated. Fifty patients were divided into two groups according to their diagnosis: idiopathic hirsutism or polycystic ovary syndrome. All patients received 125mg Flutamide once a day and Diane 35 tablets for 21 days of each month, for 12 months. We measured hirsutism scores and hormonal levels of all patients. Evaluations were done before treatment, in the 6th and 12th months of therapy. Results: There were no significant differences in Ferriman-Gallwey scores at the beginning and at the end of the therapy between the IHand PCOS groups. The decreases in Ferriman-Gallwey scores were significant in both groups in the 6th and 12th month of therapy. Combined treatment significantly decreased total and free testosterone, DHEAS and significantly increased SHBG levels in both groups andadditionally decreased levels of LH, androstenodione and LH/FSH ratio in the polycystic ovary syndrome group. Conclusion: Combined treatment was effective and safe in the treatment of hirsutism. Combined regimens have additional effects on the treatment of hirsutism.Öğe Clinical Efficacy of Low Dose Flutamide plus Diane-35 in the Treatment of Idiopathic Hirsutism and Polycystic Ovary Syndrome(STUDIO K, 2013) Boztosun, Abdullah; Acmaz, Gokhan; Ozturk, Ahmet; Muderris, Iptisam IpekObjective: Idiopathic hirsutism (IH) or polycystic ovary syndrome (PCOS) are the most common causes of hirsutism which affects 5-10 % of all women. The aim of this study was to evaluate the efficacy of flutamide plus diane 35 in the treatment of idiopathic hirsutism and polycystic ovary syndrome. Materials and Methods: 26 polycystic ovary syndrome and 24 idiopathic hirsutism patients were evaluated. Fifty patients were divided into two groups according to their diagnosis: idiopathic. hirsutism or polycystic ovary syndrome. All patients received 125mg Flutamide once a day and Diane 35 tablets for 21 days of each month, for 12 months. We measured hirsutism scores and hormonal levels of all patients. Evaluations were done before treatment, in the 6th and 12th months of therapy. Results: There were no significant differences in Ferriman-Gallwey scores at the beginning and at the end of the therapy between the IH and PCOS groups. The decreases in Ferriman-Gallwey scores were significant in both groups in the 6th and 12th month of therapy Combined treatment significantly decreased total and free testosterone, DHEAS and significantly increased SHBG levels in both groups and additionally decreased levels of LH, androstenodione and LH/FSH ratio in the polycystic ovary syndrome group. Conclusion: Combined treatment was effective and safe in the treatment of hirsutism. Combined regimens have additional effects on the treatment of hirsutism.Öğe Current Approaches to Bone-Drilling Procedures with Orthopedic Drills(Aves, 2020) Torun, Yunis; Pazarci, Ozhan; Ozturk, AhmetIn order to minimize complications during orthopedic surgery, the important of research in this field is gaining importance and more studies are being conducted. The use of robotics and autonomous systems is gaining importance to achieve the aims reducing complications, lowering operation times, and increasing the surgical reliability and effectiveness in bone drilling operations that constitute a sub-set of the Computer-Aided Orthopedic Surgery (CAOS) issue. In this study, signal processing-based approaches for breakthrough detection during bone drilling operations, robotic autonomous systems that optimize optimal plunge and drilling speed while drilling, most effective drilling parameters that affect bone perforation, and studies conducted to improve the safely and efficiency of surgical operations, such as radiological imaging, were investigated. A systematic review of recent studies on bone drilling was performed and potential research topics were proposed for possible future studies.Öğe Detection of Bone Excretion with Current Sensor in Robotic Surgery(IEEE, 2018) Torun, Yunis; Ozturk, Ahmet; Hatipoglu, Nursu; Oztemur, ZekeriyaBone drilling operation is widely used method in surgery. This operation must be done with hight care. In the case of failur some demage might be happened. In this paper a new technich is presented. By this method 1,5 mm precision is optained.Öğe Factors Affecting Complication Rates of Percutaneous Nephrolithotomy in Children: Results of a Multi-Institutional Retrospective Analysis by the Turkish Pediatric Urology Society(ELSEVIER SCIENCE INC, 2014) Onal, Bulent; Dogan, Hasan Serkan; Satar, Nihat; Bilen, Cenk Y.; Gunes, Ali; Ozden, Ender; Ozturk, Ahmet; Demirci, Deniz; Istanbulluoglu, Okan; Gurocak, Serhat; Nazli, Oktay; Tanriverdi, Orhan; Kefi, Aykut; Korgali, Esat; Silay, Mesrur Selcuk; Inci, Kubilay; Izol, Volkan; Altintas, Ramazan; Kilicarslan, Hakan; Sarikaya, Saban; Yalcin, Veli; Aygun, Cem; Gevher, Fetullah; Aridogan, Ibrahim Atilla; Tekgul, SerdarPurpose: We assessed factors affecting complication rates of percutaneous nephrolithotomy in children. Materials and Methods: We retrospectively evaluated data on 1,205 renal units in 1,157 children treated with percutaneous nephrolithotomy at 16 Turkish centers between 1991 and 2012. Of the patients 28.3% had a history of urolithiasis. Complications were evaluated according to the Satava classification system and modified Clavien grading system. Univariate and multivariate analyses were done to determine predictive factors affecting complication rates. Results: A total of 515 females and 642 males were studied. Mean +/- SD patient age was 8.8 +/- 4.7 years (range 4 months to 17 years). Mean +/- SD stone size, operative time and postoperative hospital stay were 4.09 +/- 4.06 cm 2, 93.5 +/- 48.6 minutes and 5.1 +/- 3.3 days, respectively. Postoperative stone-free rate was 81.6%. A total of 359 complications occurred in 334 renal units (27.7%). Complications were intraoperative in 118 cases and postoperative in 241. While univariate analysis revealed that stone history, positive urine culture, operative time, length of hospitalization, treatment success, punctured calyx and location of the stone significantly affected the complication rates (p <0.05), operative time, sheath size, mid calyceal puncture and partial staghorn formation were the statistically significant parameters affecting complication rates on multivariate logistic regression analysis. Conclusions: Percutaneous nephrolithotomy is the treatment of choice for most renal calculi in children. The technique is effective and safe in children, with a high success rate and a low rate of major complications. The significant factors identified should be considered by clinicians to decrease associated complication rates.Öğe IN VITRO COMPARISON OF THE EFFECTS OF DENTAL FILLING MATERIALS ON MOUSE FIBROBLASTS(TAYLOR & FRANCIS LTD, 2012) Kilic, Duygu; Kesim, Servet; Liman, Narin; Sumer, Zeynep; Ozturk, AhmetThe choice of filling material is an important factor in the clinical success of root coverage. Therefore, the cytotoxicity of filling materials must be investigated to ensure a safe biological response. The aim of this study was to compare the response of L929 mouse fibroblasts to several glass ionomer cements (GICs), i.e. conventional GIC, resin-modified glass ionomer cement (RMGIC) and polyacid-modified resin composite (PMRC), using three different methods. 1) 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay 2) agar diffusion test, 3) scanning electron microscopy The MTT test demonstrated that L929 fibroblast attachment to polyacid-modified resin composite filling material was excessive on day I, but decreased on day 3 (P < 0.05). When the cell proliferation percentages of all filling materials were compared with those of the control group (100%) on days 1 and 3, it was observed that statistically significant differences existed (P < 0.05). Although resin-modified glass ionomer cement was determined to be slightly cytotoxic according to the results of agar diffusion tests, differences between the groups were not significant (P > 0.05). In addition to our in vitro research results, chemical surface analysis techniques, measurement of the release of elements, physical surface characterization and analysis of microstructure and porosity can provide a better understanding of the biological response to filling materials.Öğe Parameters Estimation of Orthopedic Drill(IEEE, 2019) Torun, Yunis; Ozturk, Ahmet; Aksoz, Ahmet; Pazarci, OzhanIn medical drills, battery drills are highly preferred due to their comfort. Battery discharge during operation is a very important problem. For this reason, it is important to use the control method to minimize the energy consumption and to keep the drill speed in the desired range. In order to design an efficient control in any system, the system model and system parameters must be known. In this study, parameter estimation of a direct current geared motor used in medical drills was carried out by using system input/output signals. Nonlinear Least Squares method was used to estimate parameters then Genetic Algorithm optimization used to improve the model estimation performance. It was observed that the data obtained from the physical system and the model behaviors were similar in an acceptable range. Modeling improvement has been proven based on the criteria of Mean Square Error, Root Mean Square Error, Sum Square Error and Root Sum Square Error.
