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Growth And Reproduction Of Blotched Picarel (Spicara Maena Linnaeus, 1758) In The Central Aegean Sea, Turkey, Ozan Soykan, Akin Türker İlkyaz, Gülnur Meti̇n, Hasan Tuncay Kinacigi̇l
Growth And Reproduction Of Blotched Picarel (Spicara Maena Linnaeus, 1758) In The Central Aegean Sea, Turkey, Ozan Soykan, Akin Türker İlkyaz, Gülnur Meti̇n, Hasan Tuncay Kinacigi̇l
Turkish Journal of Zoology
Growth and reproduction of the blotched picarel, Spicara maena (Linnaeus, 1758), were determined based on specimens (n = 2547) collected from the central Aegean Sea between July 2004 and June 2007. The samples consisted of 71.9% females, 16.2% males, and 11.9% immature individuals. The sex ratio of females to males was 1:0.23. The length-weight relationship was W = 0.011L^{3.02}, W = 0.011L^{3.00}, and W = 0.011L^{2.99} for the combined sexes, females, and males, respectively. For all samples and both sexes the length-weight relationship showed isometric growth. The von Bertalanffy growth equation was fitted on the basis of mean length-at-age data, …
Growth And Reproduction Of Large-Scaled Gurnard (Lepidotrigla Cavillone Lacepède, 1801) (Triglidae) In The Central Aegean Sea, Eastern Mediterranean, Akin Türker İlkyaz, Gülnur Meti̇n, Ozan Soykan, Hasan Tuncay Kinacigi̇l
Growth And Reproduction Of Large-Scaled Gurnard (Lepidotrigla Cavillone Lacepède, 1801) (Triglidae) In The Central Aegean Sea, Eastern Mediterranean, Akin Türker İlkyaz, Gülnur Meti̇n, Ozan Soykan, Hasan Tuncay Kinacigi̇l
Turkish Journal of Zoology
Age, growth, and reproduction of the large-scaled gurnard were studied in the central Aegean Sea to provide fisheries managers with the essential data for science-based management. A total of 2342 samples were collected by trawl hauls between July 2004 and June 2007 from İzmir Bay (Turkey). The size of the samples ranged from 3.4 to 15.2 cm total length and the samples were composed of 35.2% females, 25.7% males and 39.1% immature individuals, with a female to male ratio of 1:0.73. The length-weight relationship was calculated as W = 0.0086L^{3.16} for all samples. The age composition of the samples was …
Effects Of Deformation Ratio On The Mechanical Properties And Microstructures Changes In An Al-Mg-Si Alloy, Hichem Farh, Rebai Guemini, Serradj Fares, Karim Djemmal
Effects Of Deformation Ratio On The Mechanical Properties And Microstructures Changes In An Al-Mg-Si Alloy, Hichem Farh, Rebai Guemini, Serradj Fares, Karim Djemmal
Turkish Journal of Physics
An investigation has been done to study the effect of deformation ratio and two-step ageing treatment on the microstructure and the mechanical properties in an Al-Mg-Si aluminum alloy. Transmission electron microscopy is used in order to follow the distribution and the morphology of the hardening precipitates. The hardness of the alloy increases with the increasing deformation ratio. The maximum of hardness increases and is shifted to low time with an increase of the deformation ratio. The density of precipitates is more increased and the precipitates become more inhomogeneously distributed when the deformation combines with two-step ageing treatments.
Danielita Gailloti N.Gen., N. Sp., Within The Evolutionary Framework Of Middle-Late Permian Dagmaritins, Demi̇r Altiner, Sevi̇nç Özkan Altiner
Danielita Gailloti N.Gen., N. Sp., Within The Evolutionary Framework Of Middle-Late Permian Dagmaritins, Demi̇r Altiner, Sevi̇nç Özkan Altiner
Turkish Journal of Earth Sciences
The name Danielita is proposed for a new dagmaritin genus characterized by a biserial arrangement of chambers with spine-like extensions at chamber corners and a perforated wall. Danielita differs from Dagmarita, from which it was derived, by a perforated wall and constitutes one of the peculiar evolutionary trends of the dagmaritin stock. Early dagmaritins evolved from Globivalvulina cyprica by the appearance of Sengoerina in the Capitanian and the frequently encountered association G. cyprica-Sengoerina-Dagmarita-Danielita in Turkey suggests that the evolutionary derivations of dagmaritin genera occurred very rapidly in the Capitanian. The subfamily Paradagmaritinae is synonymized under the subfamily Dagmaritinae. Among recently …
Application Of The Normalized Full Gradient (Nfg) Method To Resistivity Data, Ali̇ Aydin
Application Of The Normalized Full Gradient (Nfg) Method To Resistivity Data, Ali̇ Aydin
Turkish Journal of Earth Sciences
This paper proposes the application of the normalized full gradient (NFG) method to resistivity studies and illustrates that the method can greatly reduce the time and work load needed in detecting buried bodies using resistivity measurement. The NFG method calculates resistivity values at desired electrode offsets by extrapolation of a function of resistivity measurements (i.e. the gradient) to other depth levels using resistivity measurements done at one electrode offset only. The performance and reliability of the NFG method is tested on laboratory and field resistivity data from two sites by comparing the trend of the resistivity values at six or …
Dictyoptychus Douvillé: Taxonomic Revision, Phylogeny And Biogeography, Saci̇t Özer
Dictyoptychus Douvillé: Taxonomic Revision, Phylogeny And Biogeography, Saci̇t Özer
Turkish Journal of Earth Sciences
The late Campanian-Maastrichtian transgressive sequences of the southeastern Anatolia (northernmost part of the Arabian platform) and only one Maastrichtian limestone block within the ophiolitic association of the easternmost part of the Taurus Orogenic Belt contain very well-preserved specimens of Dictyoptychus Douvillé 1905. Study of Turkish specimens and also of those described in the literature reveals considerable ontogenic variability, hence need for revision of the species of the genus erected hitherto. Dictyoptychus leesi (Kühn 1929), Dictyoptychus paronai (Kühn 1929), Dictyoptychus persicus (Cox 1934), Dictyoptychus euphratica Karacabey-Öztemür 1979 and Dictyoptychus orontica Karacabey-Öztemür 1979 are accordingly re-interpreted to represent a single species synonymous …
High Frequency Plant Production Via Shoot Organogenesis And Somatic Embryogenesis From Callus In Tylophora Indica, An Endangered Plant Species, Aastha Sahai, Anwar Shahzad, Mohammad Anis
High Frequency Plant Production Via Shoot Organogenesis And Somatic Embryogenesis From Callus In Tylophora Indica, An Endangered Plant Species, Aastha Sahai, Anwar Shahzad, Mohammad Anis
Turkish Journal of Botany
An efficient and reproducible protocol has been developed for the in vitro production of an endangered medicinal climber Tylophora indica (Burm.f.) Merr. via leaf explants. Different types of calli produced on benzyladenine (BA) and thidiazuron (TDZ) supplemented Murashige and Skoog (MS) basal medium were selected for shoot induction and somatic embryogenesis studies. Calli when transferred from BA (5 µM) and TDZ (2.5 µM) to MS medium containing BA (5 µM) resulted in high frequency shoot induction (26.8 ± 0.97 shoots/culture) along with somatic embryogenesis (10.20 ± 0.37 embryoids/culture) up to 3 subculture passages. Embryoids transformed into complete plantlets when transferred …
Pollen And Seed Morphology Of Velezia L. (Caryophyllaceae) Genus In Turkey, İlham Eröz Poyraz, Ebru Ataşlar
Pollen And Seed Morphology Of Velezia L. (Caryophyllaceae) Genus In Turkey, İlham Eröz Poyraz, Ebru Ataşlar
Turkish Journal of Botany
In this study, pollen and seed morphology of Velezia L. (Caryophyllaceae) species in Turkey were investigated by light and scanning electron microscopy. The genus is represented by 5 species in Turkey: V. tunicoides P.H.Davis, V. hispida Boiss., V. quadridentata Sibth. & Sm., V. pseudorigida Hub.-Mor. and V. rigida L. Endemism ratio of the genus is 60%, which shows that Turkey is the gene center for this genus. The pollen grains of Velezia species are radially symmetrical and isopolar, oblate-spheroidal, operculate, and polypantoporate, pores with conical spinules on operculum. Pollen ornamentation, pore numbers, exine thickness, pore diameter, operculum ornamentation, and spinule …
Inclusion And Release Of Theophylline From Chitosan Based Microparticles, Niculina Popa, Ovidiu Novac, Lenuta Profire, Doina Hritcu, Marcel Ionel Popa
Inclusion And Release Of Theophylline From Chitosan Based Microparticles, Niculina Popa, Ovidiu Novac, Lenuta Profire, Doina Hritcu, Marcel Ionel Popa
Turkish Journal of Chemistry
Chitosan (CS) based microparticles for controlled release of theophylline (THP) were obtained by ionic gelation. The microparticles were characterized by laser diffraction analysis (particle size), scanning electron microscopy (SEM), FTIR spectroscopy, and thermogravimetric analysis. The average diameter of the CS-THP microparticles was 182 \mu m. The FTIR spectra confirmed that new hydrogen bonds had formed between the carbonylic group belonging to THP and the amino group of CS, while the thermogravimetric analysis showed a modified stability in the obtained particles and confirmed the presence of an interaction between the drug and CS. The THP release process was monitored for up …
A Novel Glucose Chemiluminescence Biosensor Based On A Rhodanine Derivative Chemiluminescence System And Multilayer-Enzyme Membrane, Jinghua Yu, Lei Ge, Ping Dai, Congcong Zhang, Shenguang Ge, Jiadong Huang
A Novel Glucose Chemiluminescence Biosensor Based On A Rhodanine Derivative Chemiluminescence System And Multilayer-Enzyme Membrane, Jinghua Yu, Lei Ge, Ping Dai, Congcong Zhang, Shenguang Ge, Jiadong Huang
Turkish Journal of Chemistry
Using glucose oxidase as a model enzyme, a novel rhodanine derivative chemiluminescence biosensor for the determination of glucose was formed based on multilayer-enzyme membrane as receptor, which was assembled via layer-by-layer assembly of sol-gel and glucose oxidase-gold nano-particles inside a glass tube. Compared with the traditional chemiluminescence biosensor, the proposed biosensor had some remarkable advantages, such as good selectivity of substrate, good response performance, good stability, good sensitivity, and longer service life. The linear range was from 1.0 \times 10^{-6} to 5.0 \times 10^{-2} mol L^{-1} (r = 0.9991). The detection limit was 5.0 \times 10^{-7} mol L^{-1}. In this …
When \Delta-Semiperfect Rings Are Semiperfect, Engi̇n Büyükaşik, Christian Lomp
When \Delta-Semiperfect Rings Are Semiperfect, Engi̇n Büyükaşik, Christian Lomp
Turkish Journal of Mathematics
Zhou defined \delta-semiperfect rings as a proper generalization of semiperfect rings. The purpose of this paper is to discuss relative notions of supplemented modules and to show that the semiperfect rings are precisely the semilocal rings which are \delta-supplemented. Module theoretic version of our results are obtained.
An Expansion Result For A Sturm-Liouville Eigenvalue Problem With Impulse, Şeri̇fe Faydaoğlu, Gusein Sh. Guseinov
An Expansion Result For A Sturm-Liouville Eigenvalue Problem With Impulse, Şeri̇fe Faydaoğlu, Gusein Sh. Guseinov
Turkish Journal of Mathematics
The paper is concerned with an eigenvalue problem for second order differential equations with impulse. Such a problem arises when the method of separation of variables applies to the heat conduction equation for two-layered composite. The existence of a countably infinite set of eigenvalues and eigenfunctions is proved and a uniformly convergent expansion formula in the eigenfunctions is established.
On The Qualitative Analysis Of The Uniqueness Of The Movement Of Endothelial Cells, Erdem Altuntaç, Serdal Pamuk
On The Qualitative Analysis Of The Uniqueness Of The Movement Of Endothelial Cells, Erdem Altuntaç, Serdal Pamuk
Turkish Journal of Mathematics
This paper extends the work of Pamuk (2003) by showing mathematically that the movement of endothelial cells, to the regions where active enzyme is large or where fibronectin is small, is unique. To do this, we obtain the existence and uniqueness of the steady-state solution of an initial-boundary value problem which mathematically models endothelial cell movement in tumor angiogenesis. A specific example showing the instability of this steady-state solution is provided.
On Abelian Rings, Nazim Agayev, Abdullah Harmanci, Sai̇t Halicioğlu
On Abelian Rings, Nazim Agayev, Abdullah Harmanci, Sai̇t Halicioğlu
Turkish Journal of Mathematics
Let \alpha be an endomorphism of an arbitrary ring R with identity. In this note, we introduce the notion of \alpha-abelian rings which generalizes abelian rings. We prove that \alpha-reduced rings, \alpha-symmetric rings, \alpha-semicommutative rings and \alpha-Armendariz rings are \alpha-abelian. For a right principally projective ring R, we also prove that R is \alpha-reduced if and only if R is \alpha-symmetric if and only if R is \alpha-semicommutative if and only if R is \alpha-Armendariz if and only if R is \alpha-Armendariz of power series type if and only if R is \alpha-abelian.
Possible Role Of Toxoplasmosis In Patients With First-Episode Schizophrenia*, Mehmet Tanyüksel, Özcan Uzun, Engi̇n Araz, Özgür Koru, Cahi̇t Babür
Possible Role Of Toxoplasmosis In Patients With First-Episode Schizophrenia*, Mehmet Tanyüksel, Özcan Uzun, Engi̇n Araz, Özgür Koru, Cahi̇t Babür
Turkish Journal of Medical Sciences
To determine the possible relationship between toxoplasmosis and patients with first-episode schizophrenia (FES). Materials and methods: Seventy-three subjects with FES (15-54 years old; mean: 23.4 years) and 40 healthy individuals (20-54 years old; mean: 30.3 years) were enrolled in the study. Most of the FES patients (90.4%) and the control individuals (95.0%) were male. Specific IgG and IgM antibodies to Toxoplasma gondii were investigated by enzyme-linked immunosorbent assay (ELISA), and the total amount of antibodies was investigated with the Sabin-Feldman dye test (SFDT). Results: Compared to the control individuals, study subjects had significantly more toxoplasmosis-like symptoms and more cats in …
Crimean-Congo Hemorrhagic Fever Cases In The Eastern Black Sea Region Of Turkey: Demographic, Geographic, Climatic, And Clinical Characteristics, Nurgün Günaydin, Kemaletti̇n Aydin, Gürdal Yilmaz, Hati̇ce Rahmet Çaylan, İftahar Köksal
Crimean-Congo Hemorrhagic Fever Cases In The Eastern Black Sea Region Of Turkey: Demographic, Geographic, Climatic, And Clinical Characteristics, Nurgün Günaydin, Kemaletti̇n Aydin, Gürdal Yilmaz, Hati̇ce Rahmet Çaylan, İftahar Köksal
Turkish Journal of Medical Sciences
Crimean-Congo hemorrhagic fever (CCHF) is a disease that is known since 1944 affecting many people across the world and causing a high mortality rate. The aim of this study was to determine the epidemiological and clinical characteristics of the CCHF cases in our region. Materials and methods: The present study was conducted in patients with CCHF who were hospitalized between 2004 and 2006 at Karadeniz Technical University. Demographic, geographic, climatic, and clinical characteristics of all patients were investigated. Results: A total of 102 patients with confirmed CCHF were investigated in this study. All of the patients were from rural areas. …
Comparison Of In Vitro Cytotoxicity And Genotoxicity Of Mma-Based Polymeric Materials And Various Metallic Materials, Sultan Gülçe İz, Sai̇me İsmet Gürhan, Bi̇lge Hakan Şen, Tuğba Endoğan, Nesri̇n Hasirci
Comparison Of In Vitro Cytotoxicity And Genotoxicity Of Mma-Based Polymeric Materials And Various Metallic Materials, Sultan Gülçe İz, Sai̇me İsmet Gürhan, Bi̇lge Hakan Şen, Tuğba Endoğan, Nesri̇n Hasirci
Turkish Journal of Medical Sciences
To determine the in vitro cytotoxicity and genotoxicity of some polymeric and metallic implant materials used as base materials in dentistry, based on ISO (International Organization for Standardization) and OECD (Organization for Economic Co-Operation and Development) test protocols. Materials and methods: Three different acrylate-based polymeric materials were tested for their in vitro cytotoxicity and genotoxicity (polymethylmethacrylate microspheres [PMMA], a solid cement prepared by mixing PMMA with its monomer methylmethacrylate [PMMA+MMA], a solid cement prepared by mixing PMMA, MMA, and hydroxyapatite [PMMA+MMA+HA], as wells as 4 different metallic materials (titanium [Ti grade 4], nickel alloy 625 [Ni-625], stainless steel alloy 304L …
Cellular Distribution Of Activity For Three Enzymes With Maltose Binding Protein As Fusion Partner And The Structural Implications, Özde F. Ütkür, Berna Sariyar Akbulut, Amable Hortaçsu
Cellular Distribution Of Activity For Three Enzymes With Maltose Binding Protein As Fusion Partner And The Structural Implications, Özde F. Ütkür, Berna Sariyar Akbulut, Amable Hortaçsu
Turkish Journal of Chemistry
The bacterial SEC pathway is commonly used for secretion of heterologous proteins in E. coli by fusing them to transported proteins to facilitate downstream processing. While some proteins are translocated very efficiently, some reside in the cytoplasm. In this work, maltose binding protein (MBP) was fused to 3 cytoplamic enzymes from Thermus thermophilus (serine protease, 251 residues; glucose isomerase, 381 residues; pullulanase, 718 residues) to study the protein transport from the cytoplasm by quantifying the distribution of activities in different cellular compartments. Pullulanase activity was harvested exclusively in the periplasm; however, glucose isomerase activity was harvested exclusively in the cytoplasm. …
Study Of Catalytic Activities Of Nanostructure Copper And Cobalt Supported Zsm-5 Catalysts For Conversion Of Volatile Organic Compounds, Aligholi Niaei, Dariush Salari, Seyed Ali Hosseini
Study Of Catalytic Activities Of Nanostructure Copper And Cobalt Supported Zsm-5 Catalysts For Conversion Of Volatile Organic Compounds, Aligholi Niaei, Dariush Salari, Seyed Ali Hosseini
Turkish Journal of Chemistry
This paper reports the comparison of the activities of nanostructure Cu-ZSM-5 and Co-ZSM-5 catalysts for conversion of ethyl acetate and toluene and deals with the relationship between activity and structure of catalysts. The catalysts were characterized by ICP-AES, XPS, EDX, XRD, SEM, and TEM techniques. Catalytic studies were carried out under atmospheric pressure and in a temperature range of 200-500 °C. Cu-ZSM-5 catalysts showed better activity than Co-ZSM-5, revealing higher activity of copper cations. The higher activity was ascribed to higher electro-negativity, smaller cation radius, good distribution, and specific coordination of copper cations inside Cu-ZSM-5 catalysts. The activity of catalysts …
Electro-Oxidation Of Some Non-Steroidal Anti-Inflammatory Drugs On An Alumina Nanoparticle-Modified Glassy Carbon Electrode, Mahla Tabeshnia, Hossein Heli, Ali Jabbari, Ali A. Moosavi-Movahedi
Electro-Oxidation Of Some Non-Steroidal Anti-Inflammatory Drugs On An Alumina Nanoparticle-Modified Glassy Carbon Electrode, Mahla Tabeshnia, Hossein Heli, Ali Jabbari, Ali A. Moosavi-Movahedi
Turkish Journal of Chemistry
The electro-oxidation of mefenamic acid, diclofenac, and indomethacin on glassy carbon and alumina nanoparticle-modified glassy carbon electrodes in a phosphate buffer solution at physiological pH was studied. The techniques of cyclic voltammetry, chronoamperometry, impedance spectroscopy, and steady state polarization measurements were applied. The drugs were irreversibly oxidized on bath electrodes via an anodic peak and the process was controlled by diffusion in the bulk of solution. Alumina nanoparticles increased the oxidation current, and lowered the peak and onset potentials. As such, alumina nanoparticles had an electrocatalytic effect, both kinetically and thermodynamically. The kinetic parameters of heterogeneous electron transfer and diffusion …
Synthesis And Characterization Of New Optically Active Polyamides Containing 2-(4-Nitro-1,3-Dioxoisoindolin-2-Yl)Succinic Acid And Aromatic Diamines Via Direct Polycondensation, Khalil Faghihi, Morteza Absalar, Mohsen Hajibeygi
Synthesis And Characterization Of New Optically Active Polyamides Containing 2-(4-Nitro-1,3-Dioxoisoindolin-2-Yl)Succinic Acid And Aromatic Diamines Via Direct Polycondensation, Khalil Faghihi, Morteza Absalar, Mohsen Hajibeygi
Turkish Journal of Chemistry
A new class of optically active polyamides (PAs) (6a-e) having 4-nitro-1,3-dioxoisoindolin-2-yl pendent groups were prepared by direct polycondensation reaction of 2-(4-nitro-1,3-dioxoisoindolin-2-yl) succinic acid (4) with various aromatic diamines in a medium consisting of triphenyl phosphite, calcium chloride, pyridine, and N-methyl-2-pyrrolidone. The resulting new polymers were obtained in high yields with inherent viscosities ranging between 0.32 and 0.48 dL/g, and were characterized by elemental analysis, FT-IR spectroscopy, specific rotation, solubility tests, and thermogravimetric analysis techniques (TGA and DTG). Bulky pendent groups of the polymer chains disturb interchain and intrachain interactions and make these PAs readily soluble in polar organic solvents such …
Nitrogen And Phosphorus Resorption In A Salt Marsh In Northern Turkey, Yasemi̇n Çakir, Tuğba Özbucak, Hamdi̇ Güray Kutbay, Dudu Duygu Kiliç, Ali̇ Bi̇lgi̇n, Rena Huseyinova
Nitrogen And Phosphorus Resorption In A Salt Marsh In Northern Turkey, Yasemi̇n Çakir, Tuğba Özbucak, Hamdi̇ Güray Kutbay, Dudu Duygu Kiliç, Ali̇ Bi̇lgi̇n, Rena Huseyinova
Turkish Journal of Botany
This study was conducted to investigate foliar nitrogen and phosphorus dynamics, nitrogen and phosphorus resorption, and some leaf traits (i.e. SLA=specific leaf area) in some coastal salt marsh plants located in northern Turkey. The study area is located on the east bank of the Kızılırmak River in the central Black Sea Region. There were statistically significant differences among months (from June to October) in terms of SLA in all species except for Artemisia santonicum. However, no significant differences were found with respect to P in all species. The highest N and P resorption efficiencies were found in Salicornia prostrata, whereas …
Development Of A Highly Responsive Leaf-Based Regeneration System For Peperomia Species, Mohammad Ahmadabadi, Ralph Bock
Development Of A Highly Responsive Leaf-Based Regeneration System For Peperomia Species, Mohammad Ahmadabadi, Ralph Bock
Turkish Journal of Botany
Several species in the genus Peperomia Ruiz & Pav. have giant chloroplasts in the palisade parenchyma of their leaves. Because of this unique feature, Peperomia metallica L. Linden & Rodigas has become a valuable model plant for studying plastid biology. However, the use of Peperomia for molecular studies has been limited by the lack of efficient regeneration and transformation protocols. In this work, we aimed to develop a reliable regeneration system for Peperomia from leaf explants. Using MS medium complemented with different combinations of phytohormones, a highly efficient in vitro regeneration protocol was developed for P. metallica and P. peduncularis, …
Prevalence Of Cardiac Arrhythmia In Obstructive Sleep Apnea Syndrome, Ni̇hal Akar Bayram, Bülent Çi̇ftçi̇, Selma Firat Güven, Hüseyi̇n Bayram, Hasbi̇ Erdem Di̇ker, Tahi̇r Durmaz, Telat Keleş, Engi̇n Bozkurt
Prevalence Of Cardiac Arrhythmia In Obstructive Sleep Apnea Syndrome, Ni̇hal Akar Bayram, Bülent Çi̇ftçi̇, Selma Firat Güven, Hüseyi̇n Bayram, Hasbi̇ Erdem Di̇ker, Tahi̇r Durmaz, Telat Keleş, Engi̇n Bozkurt
Turkish Journal of Medical Sciences
Repetitive transient activation of the parasympathetic and sympathetic systems in obstructive sleep apnea syndrome (OSAS) constitutes the basis for development of cardiac arrhythmias. We aimed to examine the prevalence of arrhythmias in OSAS. Materials and methods: Eighty-eight patients with suspected OSAS were included in the study. Polysomnography was performed overnight in all patients. Patients with apnea-hypopnea index (AHI) < 5 were considered OSAS negative, while patients with AHI >= 5 were OSAS positive. Arrhythmia was defined as sinus bradycardia, sinus tachycardia, > 10/h supraventricular premature beats (SVPBs), > 10/h ventricular premature beats (VEBs), complex VPBs (bigeminal, trigeminal VEB or nonsustained VT), supraventricular tachycardia, ventricular tachycardia, > 2 s sinus arrest, second or third …
Programmable Design And Implementation Of A Chaotic System Utilizing Multiple Nonlinear Functions, Recai̇ Kiliç, Fatma Yildirim Dalkiran
Programmable Design And Implementation Of A Chaotic System Utilizing Multiple Nonlinear Functions, Recai̇ Kiliç, Fatma Yildirim Dalkiran
Turkish Journal of Electrical Engineering and Computer Sciences
In addition to exhibiting a rich variety of bifurcation and chaos via tuning parameters, a chaotic system introduced by Sprott can be modeled and realized with a fixed main system block and many different changeable nonlinear function blocks such as piecewise-linear function, cubic function and other trigonometric functions. This system is very suitable for implementing a programmable chaos generator according to its changeable nonlinearity. This paper presents a FPAA (Field Programmable Analog Array)-based programmable implementation of this system. Nonlinear function blocks used in this chaotic system are modeled with FPAA programming and a model is rapidly changed for realizing other …