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Öğe The Conchoidal Twisted Surfaces Constructed by Anti-Symmetric Rotation Matrix in Euclidean 3-Space(Mdpi, 2023) Celik, Serkan; Karadag, Haci Bayram; Samanci, Hatice KusakA twisted surface is a type of mathematical surface that has a nontrivial topology, meaning that it cannot be smoothly deformed into a flat surface without tearing or cutting. Twisted surfaces are often described as having a twisted or Mobius-like structure, which gives them their name. Twisted surfaces have many interesting mathematical properties and applications, and are studied in fields such as topology, geometry, and physics. In this study, a conchoidal twisted surface is formed by the synchronized anti-symmetric rotation matrix of a planar conchoidal curve in its support plane and this support plane is about an axis in Euclidean 3-space. In addition, some examples of the conchoidal twisted surface are given and the graphs of the surfaces are presented. The Gaussian and mean curvatures of this conchoidal twisted surface are calculated. Afterward, the conchoidal twisted surface formed by an involute curve and the conchoidal twisted surface formed by a Bertrand curve pair are given. Thanks to the results obtained in our study, we have added a new type of surface to the literature.Öğe Huge Left Atrial Pseudoaneurysm in a 5-Month-Old Baby Presented with Supraventricular Tachycardia(Taiwan Soc Cardiology, 2016) Karakurt, Cemsit; Turkoz, Riza; Saritas, Bulent; Celik, Serkan; Elkiran, OzlemCardiac pseudoaneurysm is an extremely rare condition in children. It can be congenital or acquired and has been primarily described in the left side of the heart. The congenital form of pseudoaneurysm is thought to be related to muscular dysplasia of the muscular layer of the heart. The acquired form is related to myocardial infarction, infective endocarditis or chest trauma. In this report we described a 5-month-old baby with left atrial pseudoaneurysm who was referred to our hospital due to tachycardia and hemodynamic instability. After diagnosis of left atrial pseudoaneurysm, aneurysmectomy was performed and the left atrial wall was successfully repaired by surgery three days after admission. In conclusion, due to life threatening complications such as dissection, arrhythmias, compression of aneurysm and tromboembolic complications, pseudoaneurysm should be treated by surgery.Öğe THE SHAPE OPERATOR OF THE BEZIER SURFACES IN MINKOWSKI-3 SPACE(Editura Bibliotheca-Bibliotheca Publ House, 2020) Samanci, Hatice Kusak; Celik, Serkan; Incesu, MuhsinBezier surfaces are commonly used in Computer-Aided Geometric Design since it enables in geometric modeling of the objects. In this study, the shape operator of the timelike and spacelike surfaces has been analyzed in Minkowski-3 space. Then, the obtained results were applied to a numeric example.Öğe Strain and strain rate echocardiography in children with Wilson's disease(Clinics Cardive Publ Pty Ltd, 2016) Karakurt, Cemsit; Celik, Serkan; Selimoglu, Ayse; Varol, Ilknur; Karabiber, Hamza; Yologlu, SaimObjective: This study aimed to evaluate strain and strain rate echocardiography in children with Wilson's disease to detect early cardiac dysfunction. Methods: In this study, 21 patients with Wilson's disease and a control group of 20 age-and gender-matched healthy children were included. All the patients and the control group were evaluated with two-dimensional (2D) and colour-coded conventional transthoracic echocardiography by the same paediatric cardiologist using the same echocardiography machine (Vivid E9, GE Healthcare, Norway) in standard precordial positions, according to the American Society of Echocardiography recommendations 2D strain and strain rate echocardiography were performed after the ECG probes of the echocardiography machine were adjusted for ECG monitoring. Longitudinal, transverse and radial strain, and strain rate were assessed from six basal and six mid-ventricular segments of the left ventricle, as recommended by the American Society of Echocardiography. Results: Left ventricular wall thickness, systolic and diastolic diameters, left ventricular diameters normalised to body surface area, end-systolic and end-diastolic volumes, cardiac output and cardiac index values were within normal limits and statistically similar in the patient and control groups (p > 0.05). Global strain and strain rate: the patient group had a statistically significant lower peak A longitudinal velocity of the left basal point and peak E longitudinal velocity of the left basal (VAbasR) point, and higher global peak A longitudinal/ circumferential strain rate (GSRa) compared to the corresponding values of the control group (p < 0.05). Radial strain and strain rate: end-systolic rotation [ROT (ES)] was statistically significantly lower in the patient group (p < 0.05). Longitudinal strain and strain rate: end-systolic longitudinal strain [SLSC (ES)] and positive peak transverse strain (STSR peak P) were statistically significantly lower in the patient group (p < 0.05). Segmental analysis showed that rotational strain measurement of the anterior and lateral segments of the patient group were statistically significantly lower than the corresponding values of the control group (p < 0.05). Segmental analysis showed statistically significantly lower values of end-systolic longitudinal strain [STSR (ES)] of the basal lateral (p < 0.05) and end-systolic longitudinal strain [SLSC (ES)] of the basal septal segment (p < 0.05) in the patient group. End-systolic longitudinal strain [SLSC (ES)] and positive peak transverse strain (STSR peak P) were statistically significantly lower in the patient group (p < 0.05). Segmental analysis showed statistically significantly lower values of end-systolic longitudinal strain [SLSC (ES)] of the mid-anterior and basal anterior segments (p < 0.05), end-systolic longitudinal strain [STSR (ES)] measurements of the posterior and mid-posterior segments, end-systolic longitudinal displacement [LDC (ES)] of the basal posterior, mid-posterior and mid-antero-septal segments in the patient group. Conclusion: Cardiac arrhythmias, cardiomyopathy and sudden cardiac death are rare complications but may be seen in children with Wilson's disease due to copper accumulation in the heart tissue. Strain and strain rate echocardiography is a relatively new and useful echocardiographic technique to evaluate cardiac function and cardiac deformation abnormalities. Our study showed that despite normal systolic function, patients with Wilson's disease showed diastolic dysfunction and regional deformation abnormalities, especially rotational strain and strain rate abnormalities.
