PubMed İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8650

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A new and efficient numerical method for the fractional modeling and optimal control of diabetes and tuberculosis co-existence
(Amer inst Physics, 2019) Jajarmi, Amin; Baleanu, Dumitru; Ghanbari, Behzad; Baleanu, Dumitru; 56389
The main objective of this research is to investigate a new fractional mathematical model involving a nonsingular derivative operator to discuss the clinical implications of diabetes and tuberculosis coexistence. The new model involves two distinct populations, diabetics and nondiabetics, while each of them consists of seven tuberculosis states: susceptible, fast and slow latent, actively tuberculosis infection, recovered, fast latent after reinfection, and drug-resistant. The fractional operator is also considered a recently introduced one with Mittag-Leffler nonsingular kernel. The basic properties of the new model including non-negative and bounded solution, invariant region, and equilibrium points are discussed thoroughly. To solve and simulate the proposed model, a new and efficient numerical method is established based on the product-integration rule. Numerical simulations are presented, and some discussions are given from the mathematical and biological viewpoints. Next, an optimal control problem is defined for the new model by introducing four control variables reducing the number of infected individuals. For the control problem, the necessary and sufficient conditions are derived and numerical simulations are given to verify the theoretical analysis.
A new fractional model and optimal control of a tumor-immune surveillance with non-singular derivative operator
(Amer inst Physics, 2019) Baleanu, D.; Baleanu, Dumitru; Jajarmi, A.; Sajjadi, S. S.; Mozyrska, D.; 56389
In this paper, we present a new fractional-order mathematical model for a tumor-immune surveillance mechanism. We analyze the interactions between various tumor cell populations and immune system via a system of fractional differential equations (FDEs). An efficient numerical procedure is suggested to solve these FDEs by considering singular and nonsingular derivative operators. An optimal control strategy for investigating the effect of chemotherapy treatment on the proposed fractional model is also provided. Simulation results show that the new presented model based on the fractional operator with Mittag-Leffler kernel represents various asymptomatic behaviors that tracks the real data more accurately than the other fractional- and integer-order models. Numerical simulations also verify the efficiency of the proposed optimal control strategy and show that the growth of the naive tumor cell population is successfully declined. Published under license by AIP Publishing.
A zero-crossing technique for the multidetermination of thiamine HCl and pyridoxine HCl in their mixture by using one-dimensional wavelet transform
(Elsevier, 2003) Dinç, E; Baleanu, Dumitru; Baleanu, D; 56389
A new zero-crossing technique based on one-dimensional wavelet transform (WT) was developed and applied on a commercial vitamin product and binary mixtures containing thiamine HCl and pyridoxine HCl in the presence of the interference of the analysed signals. We selected from the data of the UV-Vis absorption spectra a signal consisting of 1150 points corresponding to the concentration range 8-32 mg/ml for both vitamins and we subjected it to one-dimensional continuous WT Mexican (MEXICAN) and Meyer (MEYER). Since the peaks of the transformed signals were bigger than original ones a zero crossing technique was applied to obtain the regression equations. The validity of Beer-Lambert law was assumed for the transformed signals. An appropriate scale setting was choosing to obtain an alternative calibration for each method. The basic concepts about wavelet method were briefly explained and MATLAB 6.5 software was used for one-dimensional wavelet analysis, The obtained results were successfully compared among each other and with those obtained by other literature methods. The developed method is rapid, easy to apply. not expensive and suitable for analysing of the overlapping signals of compounds in their mixtures without any chemical pre-treatment. (C) 2003 Elsevier Science B.V. All rights reserved.
An Efficient Computational Technique for Fractal Vehicular Traffic Flow
(Mdpi, 2018) Kumar, Devendra; Baleanu, Dumitru; Tchier, Fairouz; Singh, Jagdev; Baleanu, Dumitru; 56389
In this work, we examine a fractal vehicular traffic flow problem. The partial differential equations describing a fractal vehicular traffic flow are solved with the aid of the local fractional homotopy perturbation Sumudu transform scheme and the local fractional reduced differential transform method. Some illustrative examples are taken to describe the success of the suggested techniques. The results derived with the aid of the suggested schemes reveal that the present schemes are very efficient for obtaining the non-differentiable solution to fractal vehicular traffic flow problem.
Asymptotic solutions of fractional interval differential equations with nonsingular kernel derivative
(Amer inst Physics, 2019) Salahshour, S.; Baleanu, Dumitru; Ahmadian, A.; Salimi, M.; Ferrara, M.; Baleanu, D.; 56389
Realizing the behavior of the solution in the asymptotic situations is essential for repetitive applications in the control theory and modeling of the real-world systems. This study discusses a robust and definitive attitude to find the interval approximate asymptotic solutions of fractional differential equations (FDEs) with the Atangana-Baleanu (A-B) derivative. In fact, such critical tasks require to observe precisely the behavior of the noninterval case at first. In this regard, we initially shed light on the noninterval cases and analyze the behavior of the approximate asymptotic solutions, and then, we introduce the A-B derivative for FDEs under interval arithmetic and develop a new and reliable approximation approach for fractional interval differential equations with the interval A-B derivative to get the interval approximate asymptotic solutions. We exploit Laplace transforms to get the asymptotic approximate solution based on the interval asymptotic A-B fractional derivatives under interval arithmetic. The techniques developed here provide essential tools for finding interval approximation asymptotic solutions under interval fractional derivatives with nonsingular Mittag-Leffler kernels. Two cases arising in the real-world systems are modeled under interval notion and given to interpret the behavior of the interval approximate asymptotic solutions under different conditions as well as to validate this new approach. This study highlights the importance of the asymptotic solutions for FDEs regardless of interval or noninterval parameters. Published under license by AIP Publishing.
Average intensity and spreading of cosh-Gaussian laser beams in the turbulent atmosphere
(Optical Soc Amer, 2005) Eyyuboglu, HT; Baykal, Y; 7688; 7812
The average intensity and spreading of cosh-Gaussian laser beams in the turbulent atmosphere are examined. Our research is based principally on formulating the average-intensity profile at the receiver plane for cosh-Gaussian excitation. The limiting cases of our formulation for the average intensity are found to reduce correctly to the existing Gaussian beam wave result in turbulence and the cosh-Gaussian beam result in free space (in the absence of turbulence). The average intensity and the broadening of the cosh-Gaussian beam wave after it propagates in the turbulent atmosphere are numerically evaluated versus source size, beam displacement, link length, structure constant, and two wavelengths of 0.85 and 1.55 mum, which are most widely used in currently employed free-space-optical links. Results indicate that in turbulence the beam is widened beyond its free-space diffraction values. At the receiver plane, analogous to the case of free space, this diffraction eventually leads to transformation of the cosh-Gaussian beam into an oscillatory average-intensity profile with a Gaussian envelope. (C) 2005 Optical Society of America.
Certain Fractional Integral Formulas Involving the Product of Generalized Bessel Functions
(Hindawi Ltd, 2013) Baleanu, D.; Baleanu, Dumitru; Agarwal, P.; Purohit, S. D.; 56389
We apply generalized operators of fractional integration involving Appell's function F-3(.) due to Marichev-Saigo-Maeda, to the product of the generalized Bessel function of the first kind due to Baricz. The results are expressed in terms of the multivariable generalized Lauricella functions. Corresponding assertions in terms of Saigo, Erdelyi-Kober, Riemann-Liouville, and Weyl type of fractional integrals are also presented. Some interesting special cases of our two main results are presented. We also point out that the results presented here, being of general character, are easily reducible to yield many diverse new and known integral formulas involving simpler functions.
Comparative analysis on wavelet-based detection of finite duration low-amplitude signals related to ventricular late potentials
(Iop Publishing Ltd, 2004) Mousa, A; Yilmaz, A
Ventricular late potentials (VLPs) are considered as a noninvasive marker of patients with myocardial infarction, who are prone to the development of ventricular tachycardia. This paper investigates the effects of variations in physical properties of myocardial infarcts in terms of their effects on the parametric variations in VLP analysis. A sufficiently large set of signals underlining the behavior of physical parameters was employed to represent the effect of physical size, position, orientation and type of infarct. The approximated signals are variations from real electrocardiography signals by adding potentials representing late potentials based on duration, frequency, amplitude and position. The aim is not to exactly model VLP but rather to generate an approximate set of signals to examine the performance of the standard methods for different possibilities in infarct dynamics. We investigate some of the detection approaches together with their related assumptions, and try to pinpoint the drawbacks and inaccuracies of these methods and also their assumptions. The three widely accepted criteria-QRS duration, root-mean-square and duration of the signal at the end of QRS for VLP detection-were used in the investigation. Results from the application of these parameters to the set of signals are presented. In addition we investigate the physical nature of an infarct and list a number of possible reasons that might be the cause of a low success rate for the detection of additive potentials. To improve the performance of the common methods, two more wavelet transform parameters are added to those of the standard methods. The method derived from this analysis is presented as an alternative means for the detection of late signals named as delayed potentials, a more general class that includes VLP as a subset.
Comparative study of the continuous wavelet transform, derivative and partial least squares methods applied to the overlapping spectra for the simultaneous quantitative resolution of ascorbic acid and acetylsalicylic acid in effervescent tablets
(Elsevier Science Bv, 2005) Dinç, E; Baleanu, Dumitru; Ozdemir, A; Baleanu, D; 56389
The simultaneous spectrophotometric determination of ascorbic acid (AA) and acetylsalicylic acid (ASA) in effervescent tablets in the presence of the overlapping spectra was accomplished by the continuous wavelet transform (CWT), derivative spectrophotometry (DS) and partial least squares (PLS) approaches without using any chemical pre-treatment. CWT and DS calibration equations for AA and ASA were obtained by measuring the CWT and DS amplitudes corresponding to zero-crossing points of spectra obtained by plotting continuous wavelet coefficients and first-derivative absorbance values versus the wavelengths, respectively. The PLS calibration was constructed by using the concentration set and its full absorbance data consisting of 850 points from 220 to 305 urn in the range of 210-310 nun. These three methods were tested by analyzing the synthetic mixtures of the above drugs and they were applied to the real samples containing two commercial pharmaceutical preparations of subjected drugs. A comparative study was carried out by using the experimental results obtained from three analytical methodologies and precise and accurate results were obtained. (c) 2004 Published by Elsevier B.V.
Computerized detection and segmentation of mitochondria on electron microscope images
(Wiley, 2012) Hassanpour, Reza; Mumcuoglu, E. U.; Hassanpour, R.; Taşel, Faris Serdar; Tasel, S. F.; Perkins, G.; Martone, M. E.; Gurcan, M. N.; 55346
Mitochondrial function plays an important role in the regulation of cellular life and death, including disease states. Disturbance in mitochondrial function and distribution can be accompanied by significant morphological alterations. Electron microscopy tomography (EMT) is a powerful technique to study the 3D structure of mitochondria, but the automatic detection and segmentation of mitochondria in EMT volumes has been challenging due to the presence of subcellular structures and imaging artifacts. Therefore, the interpretation, measurement and analysis of mitochondrial distribution and features have been time consuming, and development of specialized software tools is very important for high-throughput analyses needed to expedite the myriad studies on cellular events. Typically, mitochondrial EMT volumes are segmented manually using special software tools. Automatic contour extraction on large images with multiple mitochondria and many other subcellular structures is still an unaddressed problem. The purpose of this work is to develop computer algorithms to detect and segment both fully and partially seen mitochondria on electron microscopy images. The detection method relies on mitochondria's approximately elliptical shape and double membrane boundary. Initial detection results are first refined using active contours. Then, our seed point selection method automatically selects reliable seed points along the contour, and segmentation is finalized by automatically incorporating a live-wire graph search algorithm between these seed points. In our evaluations on four images containing multiple mitochondria, 52 ellipses are detected among which 42 are true and 10 are false detections. After false ellipses are eliminated manually, 14 out of 15 fully seen mitochondria and 4 out of 7 partially seen mitochondria are successfully detected. When compared with the segmentation of a trained reader, 91% Dice similarity coefficient was achieved with an average 4.9 nm boundary error.
Continuous wavelet and derivative transforms for the simultaneous quantitative analysis and dissolution test of levodopa-benserazide tablets
(Elsevier, 2007) Dinc, Erdal; Baleanu, Dumitru; Kaya, Sueha; Doganay, Tanver; Baleanu, Dumitru; 6981; 133597
Simultaneous analyses and dissolution tests of levodopa-benserazide tablets were carried out by continuous wavelet transform (CWT) and classic derivative spectrophotometry (DS) without using any chemical separation step. The developed two spectrophotometric resolutions are based on the transformation of the original UV spectra. The original absorption spectra of levodopa and benserazide in the concentration range of 1-80 mu g/mL and 5-240 mu g/mL in USP simulated gastric juice were registered in the spectral range of 250-310 nm, respectively. Various wavelet families and different spectrophotometric derivative orders were tested to find the optimal signal processing for obtaining desirable calibration graphs and reliable determinations of the investigated drugs. Under the optimized conditions of the methods, symlets wavelet family using a = 128 with sixth order (SYM6-CWT) and the first derivative transform with Delta lambda = 10 nm were identified as optimal signal processing methods for the determinations and dissolution tests. The calibration functions for each drug were obtained by measuring the values of the CWT and derivative amplitudes. The validation of the developed methods was confirmed by analyzing various synthetic mixtures of the investigated drugs. Mean recovery values were found between 99.1% and 104.7% for DS and 100% and 102.9% for CWT, respectively for determination of BEN and LEV in synthetic mixtures. Each developed approaches were successfully applied to the simultaneous determination and dissolution test of levodopa and benserazide in their commercial tablets and a good agreement was observed. (c) 2007 Elsevier B.V. All rights reserved.
Control of trichloroethylene emissions from sparging systems by horizontal bio- and chemo-barriers
(Selper Ltd, Publications Div, 2005) Tezel, U; Demirer, GN; Uludag-Demirer, S
The scope of this study was to develop a continuous system to clean-up a trichloroethylene (TCE) contaminated gas stream, where biotic and abiotic removal mechanisms are undertaken sequentially simulating the horizontal bio- and chemo-barriers proposed for the in-situ remediation of the contaminated sites. The bio- and chemo-barriers were simulated by using glass columns packed with granular anaerobic mixed culture and Fe(0) filings, respectively. The effect of gas residence time, which is adjusted by the gas flowrate, on the TCE removal efficiency of the reactor system was investigated. TCE removal efficiency of over 90% was achieved at gas residence times above 1hr. Furthermore, the effluent of reactor system contained only ethane and ethylene, which are non-toxic by-products of TCE reduction reactions, along with trace amounts of TCE.
Effect of anisotropy on bit error rate for an asymmetrical Gaussian beam in a turbulent ocean
(Optical Soc Amer, 2018) Ata, Yalcin; Baykal, Yahya; 7812
Effect of anisotropy on the average bit error rate (BER) is investigated when an asymmetrical Gaussian beam is propagated in an anisotropic turbulent ocean. BER is found to decrease in response to an increase in anisotropy levels in the x and y directions. Higher average signal-to-noise ratio, wavelength, and microscale length yield smaller BER values. BER starts to rise with an increase in the asymmetrical beam source size in the x and y directions, source size ratio in the x and y directions, salinity and temperature contribution factor, the dissipation of the mean squared temperature, and the propagation distance. At the fixed source size ratio in the x and y directions of the asymmetrical beam source size, larger source sizes increase BER. An anisotropic turbulent ocean seems to exhibit better BER values as compared with an isotropic turbulent ocean. (c) 2018 Optical Society of America
Effect of strong atmospheric non-Kolmogorov turbulence on the M-ary PSK subcarrier intensity modulated free space optical communications system performance
(Optical Soc Amer, 2019) Ata, Yalcin; Gökçe, Muhsin Caner; Baykal, Yahya; Gokce, Muhsin C.; 7812
Atmospheric turbulence is one of the significant phenomena that degrades the free space optical (FSO) communications system performance, and thus designers need to define the requirements related to turbulence and optimize the system design to ensure optimum performance. The subcarrier intensity modulation (SIM) shows superiority in terms of bandwidth usage over the other modulation techniques. Performance of FSO communication systems exercising M-ary phase-shift-keying (PSK) SIM with the PIN photodiode receiver is evaluated in non-Kolmogorov strong atmospheric turbulence when a Gaussian beam is used as the excitation. Bit-error-rate (BER) of PSK SIM FSO communication systems is examined, and the results are presented versus the non-Kolmogorov atmospheric turbulence and positive-intrinsic-negative (PIN) photodetector parameters such as PIN photodetector responsivity, equivalent load resistor, modulation order, noise factor, bandwidth, propagation distance, and beam source size. (C) 2019 Optical Society of America
Impaired redox homeostasis in the heart left ventricles of aged rats experiencing fast-developing severe hypobaric hypoxia
(Springer, 2019) Agascioglu, Eda; Colak, Ridvan; Demirel, Haydar; Cakatay, Ufuk
Despite its rare occurrence, humans and animals have been prone to getting fast developing severe hypobaric hypoxia. Understanding the redox homeostasis related response of an aging heart to this type of hypoxia are crucially important, since the metabolism of myocardial tissue depends on the redox status of proteins. Rodents can tolerate hypoxic stress better than human subjects. This study was aimed at investigating the effects of fast developing severe hypobaric hypoxia on redox status biomarkers; such as, advanced oxidation protein products (AOPP), lipid hydroperoxides (LHPs), protein carbonyl groups (PCO), protein thiol groups (P-SH), and total thiol groups (T-SH) on the myocardial left ventricles of young and aged Wistar rats. The rats were gradually ascended and exposed to an 8000-meter hypobaric hypoxia. While AOPP levels showed no difference, the TSH and PSH concentrations decreased, and the PCO and LHP increased in both of the hypoxic groups than the controls. The TSH and PSH were lower, and AOPP, PCO and LHP were found to be higher in the elderly hypoxic groups than in the young ones. The significant outcome of the study represents that an 8000-meter hypobaric hypoxia could be considered as a severe hypoxic stress, but not life-treating for the rats and would affect both the young and aged left ventricles similarly in respect to impaired redox status. However, if the percentage increases are taken into consideration, it seems that the higher rate of protein oxidation occurs in young hearts; meanwhile aged hearts are more prone to T-SH oxidation.
Modeling of an interface between isorefractive media by a resistive surface
(Optical Soc Amer, 2018) Basdemir, Husnu Deniz; Başdemir, Hüsnü Deniz; 20399
In this study, the scattering of plane waves by a half-plane with different face impedances, which lie between isorefractive media, is analyzed. A new approach for the solution of this scenario is proposed. According to this proposal, the problem of isorefractive media and an impedance half-plane is modeled by a junction of resistive and impedance sheets. Thus the diffraction coefficient of the construction is obtained with the aid of the equivalent problem. The uniform expression of the diffracted waves is derived by the method of the uniform theory of diffraction. The scattered and diffracted waves are investigated numerically. (c) 2018 Optical Society of America
New variable-order fractional chaotic systems for fast image encryption
(Amer inst Physics, 2019) Wu, Guo-Cheng; Baleanu, Dumitru; Deng, Zhen-Guo; Baleanu, Dumitru; Zeng, De-Qiang; 56389
New variable-order fractional chaotic systems are proposed in this paper. A concept of short memory is introduced where the initial point in the Caputo derivative is varied. The fractional order is defined by the use of a piecewise constant function which leads to rich chaotic dynamics. The predictor-corrector method is adopted, and numerical solutions of fractional delay equations are obtained. Then, this concept is extended to fractional difference equations, and generalized chaotic behaviors are discussed numerically. Finally, the new fractional chaotic models are applied to block image encryption and each block has a different fractional order. The new chaotic system improves security of the image encryption and saves the encryption time greatly. Published under license by AIP Publishing.
Oral Trail Making Task as a Discriminative Tool for Different Levels of Cognitive Impairment and Normal Aging
(Oxford Univ Press, 2013) Bastug, G.; Ozel-Kizil, E. T.; Sakarya, A.; Altintas, O.; Kirici, S.; Altunoz, U.
The Trail Making Test (TMT) is a useful measure of executive dysfunction in elderly subjects. This study aims to investigate the discriminative validity of the oral version of the TMT (OTMT), which can be administered to subjects with visual or motor disabilities, in elderly patients with Mild Cognitive Impairment (MCI; n = 30), Alzheimer's disease (AD; n = 30), and healthy controls (HCs; n = 25). The WAIS-R Digit Span Backwards Subscale, written form of the Trail Making Task, the Clock Drawing Test, the AD Assessment Scale-Cognitive Subscale, and the OTMT were also administered to all participants in order to examine the concurrent validity of the OTMT. The OTMT part B discriminated between patients with MCI, AD, and HC correctly. The OTMT completion time was not correlated with age, but was negatively correlated with education. In conclusion, the OTMT (mostly part B) is a valid and practical measurement tool for different levels of cognitive impairment, especially for patients with visual or motor disabilities for whom the classical written form is not feasible.
Paulus Aegineta Review of Spine-Related Chapters in "epitomoe Medicoe Libri Septem
(Lippincott Williams & Wilkins, 2013) Er, Uygur; Naderi, Sait
Study Design. Analysis of chapters related to spinal fractures and dislocations of an important medical book from medieval age. A historical study. Objective. To present the sections on spinal fractures and dislocations in the treatise of Paulus Aegineta or Paul of Aegina, and to discuss their relationship with preceding and subsequent literature. Summary of Background Data. Paul of Aegina was influenced by precedent great authors and provided a significant link in the transmission of the surgical knowledge to present day via the prominent physicians of Islamic golden age. Methods. The edition on which this study is based was translated from Greek into English by Francis Adams and was published in 1846 by The Sydenham Society in London in 3 volumes. The related sections were examined and compared with the treatises of earlier and subsequent writers. Results. Although Paul of Aegina was influenced by Hippocrates, Celsus, and Galen, he also put forward his own opinions. The most prominent representatives of the Islamic Golden Age, Rhazes, Albucasis, Avicenna, and Haly Abas were influenced by Paul of Aegina. Conclusion. Paul of Aegina, who was the last representative of the Byzantine School, compiled approximately 1000 years of medical knowledge up to his own era. By taking on this task, he provided a significant link in the transmission of ancient knowledge to later generations. He is also considered as a bridge between Western and Eastern medicines as he conveyed medical knowledge of the ancient era to Islamic authors.
Performance of M-ary pulse position modulation for aeronautical uplink communications in an atmospheric turbulent medium
(Optical Soc Amer, 2019) Ata, Yalcin; Gökçe, Muhsin Caner; Baykal, Yahya; Gokce, Muhsin Caner; 7812
This paper discusses the bit-error-rate (BER) performance of an aeronautical uplink optical wireless communication system (OWCS) when a Gaussian beam is employed and the M-ary pulse position modulation technique is used in an atmospheric turbulent medium. Weak turbulence conditions and log-normal distribution are utilized. The Gaussian beam is assumed to propagate on a slant path, the transmitter being ground-based, and the airborne receiver is on-axis positioned. Variations of BER are obtained against the variations in the link length, Gaussian beam source size, zenith angle, wind speed, wavelength, modulation order, data bit rate, equivalent load resistor, avalanche photodetector gain, and detector quantum efficiency. It is observed that the performance of the aeronautical uplink OWCS is affected from atmospheric turbulence significantly. (C) 2019 Optical Society of America

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