Altintaş, A. | Ünsalan, Cem | Keskin, A.U. | Yencilek, F.
Conference Object | 2010 | 2010 15th National Biomedical Engineering Meeting, BIYOMUT2010
Extracorporeal Shock Wave Lithotrispy (ESWL) is a procedure based on sound waves to crash kidney stones on the focus. The sound waves are sent to the body of patient when the kidney stone is not even on the focus. When the stone is not on the focus, the sound waves can damage the soft tissue of the kidney. This damage can be prevented by a feedback mechanism that determines the place of kidney stones depending on the images taken from ESWL device. In this study, an automated system is developed to detect kidney stones from X ray images. ©2010 IEEE.
Bicakçi, M. | Taş, A.C.
Brushite (CaHPO4·2H2O, dicalcium phosphate dihydrate) is known to be the precursor to the mineralized portion (HA: calcium hydroxyapatite, Ca10(PO4)6(OH)2) of hard tissues in the biological crystallization processes. In other words, it can be readily asserted that there must be a point of equilibrium (within the three-dimensional pH, temperature and concentration space) between brushite and hydroxyapatite phases in physiological solutions. While brushite is acidic, hydroxyapatite is a basic phase. It is also known that mixtures which contain these phases, in appropriate mixing ratios, could undergo a neutralization reaction in aqueo . . .us solutions at the human body temperature of 36.5 °C. Based on these facts, it would be possible to produce bone cements, for orthopedic applications, from the biphasic powder mixtures of brushite and apatite. The feasability of synthesizing these biphasic powder mixtures in variable phase ratios have been tested, for the first time in this study, by using a single-step chemical precipitation process. This paper explains this novel process and analyzes the X-ray diffraction and infrared spectroscopy data obtained from these powders. ©2010 IEEE
Girişken, G. | Taş, A.C.
Brushite (DCPD, CaHPO4·2H2O, dicalcium phosphate dihydrate) and octacalcium phosphate (OCP, Ca8(HPO 4)2(PO4)4·5H2O) are two important biomineralization phases of the musculoskeletal system of living vertebrates which respectively crystallize in the very first instants of hard tissue formation accompanied by calcification, and then transform into the so-called bone mineral named as calcium-deficient hydroxyapatite (CDHA, Ca 10-x(HPO4)x(PO4)6-x(OH) 2-x). The utilization of these two phases in the surgical treatment of bone defects and voids has lately been the focus of interest of a significant number of research projects. Although th . . .e synthesis of DCPD is quite easy and reproducible, the same cannot be said for that of OCP. Biomineralization solutions which use DCPD as the starting material and can allow the economical transformation of DCPD into OCP have been developed in this study. This paper explains the preparation conditions of these solutions and elucidates the X-ray diffraction and infrared spectroscopy data of the phases formed. ©2010 IEEE
Keskin, A.Ü. | Koyuncu, C.
A simple liquid sensing and measurement system for determining the level of cryogen in a tissue cryopreservation container is described. Liquid-gas boundary determination is made by detecting a thermal transient of the series-connected light emitting diodes. An electronic control and display unit located on the outer wall of the container indicates the level of cryogenic liquid, and alarms the operator if it reaches a pre-determined critical level. ©2010 IEEE.
Işik, E.Ö. | Nelson, S.J.
In this study, we analyzed the MR spectroscopic and MR diffusion weighted imaging parameter differences among the subtypes of grade 3 brain tumor patients (anaplastic astrocytoma, oligodendroglioma, and oligoastrocytoma). We observed higher lipid values in the tumor regions of oligodendrogliomas than both astrocytomas and oligoastrocytomas. According to these results, there were not significant MR spectroscopic or MR diffusion differences between the subtypes of grade 3 brain tumors for this patient population and except lipid it would be acceptable to combine the data of these subgroups for future studies. ©2010 IEEE.
Hindistan, Ö. | Mert, I. | Mandel, S. | Taş, A.C.
Brushite (CaHPO4·2H2O, dicalcium phosphate dihydrate) is an important component of the powders of orthopedic cements. Brushite-containing cements were produced over the last ten years, and could only be submitted to the commercial and clinical use of European orthopedic surgeons in the last five years. Until now, brushite powders could be produced only as thin and long crystals with lenghts over the range of 70 to 100 microns, and the water-lily-shaped novel crystals presented here cannot be obtained yet. The synthesis procedure which allowed the production of this novel morphology is presented in this study. ©2010 IEEE.
Güven, Y. | Barkana, D.E.
Recent research in orthopedic surgeries indicates that computer-assisted robotic systems have shown that robots may improve the precision and accuracy of the surgery which in turn leads to better long-term outcomes. An orthopedic robotic system called OrthoRoby and an intelligent control architecture that will be used in bone cutting operations were developed. In this paper, a medical user interface was developed and integrated into the OrthoRoby system. Medical user interface used Computed Tomography (CT) images of the patients' bone. ©2010 IEEE.
Demir, A. | Keskin, A.Ü. | Ünsal, M. | Bayram, A.
Because blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) pulse sequences have rapidly changing high field gradients, almost all currently available equipment which measure and record the response of a patient to visual or audio stimuli in fMRI employ fiber-optics based systems. In this work we introduce a simple and low cost patient response set up which does not require fiber-optics based sensors and interface. The basis of the method is to transmit an on/off light signal through the RF shielded window of the scanning room. The performance of the proposed measurement set up is tested using fMRI seque . . .nces in a 3 Tesla MRI unit. ©2010 IEEE
Somunyudan, M.F. | Topaloglu, N. | Ergenoglu, M.Ü. | Gülsoy, M.
2010 15th National Biomedical Engineering Meeting, BIYOMUT2010 -- 21 April 2010 through 24 April 2010 -- Antalya -- 80917
Kurtuluş, G. | Taş, A.C.
Struvite (MgNH4PO4·6H2O, magnesium ammonium phosphate hexahydrate) is one of the urinary tract stones seen in humans and animals. Moreover, this phase is frequently encountered in the waste water treatment and purification plants. Struvite powders were easily synthesized, without any pH control precautions, in this study and the powders heated in an air atmosphere were observed to lose their crystal structure. This amorphous but struvite-related substance was found to crystallize itself back into struvite at room temperature when soaked in ammonium ion-containing aqueous solutions. Struvite powders were also found to transform, at 3 . . .6.5 °C and in 72 hours, into the human bone mineral, when immersed in solutions having similar alkali (Na and K) and alkaline earth (Ca) ions such as those of body fluids. As-synthesized and transformed powders were analyzed with X-ray diffraction, scanning electron microscopy and Fourier-transform infrared spectroscopy. ©2010 IEEE
Karaaslan, I.Ş. | Bayrakçeken, Fuat
BBQ (4,4?-Bis-(2-butyloctyloxy)-p-quaterphenyl) is one of the laser dyes, which appears as white, crystalline solid. A dye laser is a laser which uses an organic dye as the lasing medium, usually as a liquid solution. Some of the dyes are Rhodamine 6G, coumarin, stilbene, umbelliferone, tetracene and others. In this work, BBQ in cyclohexane is investigated in the room temperature spectroscopically. The used spectroscopic methods are Raman, FTIR and UV-Visible. The structure properties are identified with the spectroscopic methods. A dye can usually be used for a much wider range of wavelengths. The wide bandwidth makes them particul . . .arly suitable for tunable lasers and pulsed lasers. The solvent chosen cyclohexane is a cycloalkane. ©2010 IEEE