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Imaging Modalities Used In Diagnosis And Follow-Up Of Patients With Takayasu's Arteritis, Ayşe Bahar Keleşoğlu Di̇nçer, Levent Kiliç, Abdulsamet Erden, Umut Kalyoncu, Tuncay Hazirolan, Sedat Ki̇raz, Ömer Karadağ
Imaging Modalities Used In Diagnosis And Follow-Up Of Patients With Takayasu's Arteritis, Ayşe Bahar Keleşoğlu Di̇nçer, Levent Kiliç, Abdulsamet Erden, Umut Kalyoncu, Tuncay Hazirolan, Sedat Ki̇raz, Ömer Karadağ
Turkish Journal of Medical Sciences
Background/aim: Takayasu's arteritis (TA) is a rare, large-vessel vasculitis of unknown etiology, affecting aortic arch, and its main branches. Noninvasive imaging methods are frequently used in diagnosis and follow-up in Takayasu's arteritis. Studies investigating optimal timing of follow up imaging are rare. This study is aimed to investigate the radiologic changes in vascular involvements of Takayasu's arteritis patients one year after diagnosis. Materials and methods: Database of our Vasculitis Center was analyzed retrospectively and 97 patients were included into the study. Demographic, clinical, radiological, and therapeutic findings of patients were recorded. Patients with follow-up imaging after approximately one year of …
Does Fludrocortisone Treatment Cause Hypomagnesemia In Children With Primaryadrenal Insufficiency?, İbrahi̇m Mert Erbaş, Selda Ayça Altincik, Gönül Çatli, Tolga Ünüvar, Bayram Özhan, Ayhan Abaci, Ahmet Anik
Does Fludrocortisone Treatment Cause Hypomagnesemia In Children With Primaryadrenal Insufficiency?, İbrahi̇m Mert Erbaş, Selda Ayça Altincik, Gönül Çatli, Tolga Ünüvar, Bayram Özhan, Ayhan Abaci, Ahmet Anik
Turkish Journal of Medical Sciences
Background/aim: Aldosterone is a mineralocorticoid that secreted from adrenal glands and a known factor to increase magnesium excretion by direct and indirect effects on renal tubular cells. Although the frequency of hypomagnesemia was found to be approximately 5% in adult studies, there is no study in the literature investigating the frequency of hypomagnesemia in children by using fludrocortisone, which has a mineralocorticoid activity. Materials and methods: A multi-center retrospective study was conducted, including children who were under fludrocortisone treatment for primary adrenal insufficiency and applied to participant pediatric endocrinology outpatient clinics. Results: Forty-three patients (58.1% male, 41.9% prepubertal) included in …
Turkish Reliability And Validity Study Of The Medical Outcomes Study (Mos) Sleep Scale Inpatients With Obstructive Sleep Apnea, Bülent Devri̇m Akçay, Duygu Akçay, Si̇nan Yetki̇n
Turkish Reliability And Validity Study Of The Medical Outcomes Study (Mos) Sleep Scale Inpatients With Obstructive Sleep Apnea, Bülent Devri̇m Akçay, Duygu Akçay, Si̇nan Yetki̇n
Turkish Journal of Medical Sciences
Background/aim: The purpose of the present study was to evaluate the Turkish reliability and validity of the medical outcomes study (MOS) sleep scale in patients who have obstructive sleep apnea. Materials and methods: The data of the study were collected from 120 adult patients with obstructive sleep apnea and from 90 healthy individuals between March 04 and May 31, 2019. Results: The Cronbach's α internal consistency reliability coefficient of the MOS sleep scale was found as 0.82. The test-retest reliability was acceptable (r = 0.76-0.94). Six factors were identified by the factor analysis. These were the same as those in …
Efficacy, Retention, And Safety Of Tofacitinib In Real-Life: Hur-Bio Monocentric Experience, Emre Bi̇lgi̇n, Furkan Ceylan, Emi̇ne Duran, Bayram Fari̇soğullari, Ertuğrul Çağri Bölek, Gözde Kübra Yardimci, Levent Kiliç, Ali̇ Akdoğan, Ömer Karadağ, Şazi̇ye Şule Apraş Bi̇lgen, Sedat Ki̇raz, Ali̇ İhsan Ertenli̇, Umut Kalyoncu
Efficacy, Retention, And Safety Of Tofacitinib In Real-Life: Hur-Bio Monocentric Experience, Emre Bi̇lgi̇n, Furkan Ceylan, Emi̇ne Duran, Bayram Fari̇soğullari, Ertuğrul Çağri Bölek, Gözde Kübra Yardimci, Levent Kiliç, Ali̇ Akdoğan, Ömer Karadağ, Şazi̇ye Şule Apraş Bi̇lgen, Sedat Ki̇raz, Ali̇ İhsan Ertenli̇, Umut Kalyoncu
Turkish Journal of Medical Sciences
Background/aim: To assess the real-life efficacy, retention rate, and safety data of tofacitinib in rheumatoid arthritis (RA) patients. Materials and methods: We analyzed all patients registered in the HURBİO database who received at least 1 dose of tofacitinib. Patients who received at least one dose were included in retention analysis; patients with at least 1 control visit were included in efficacy and safety analysis. Factors predicting good response at the last follow-up visit were analyzed by logistic regression analysis. Drug retention rates were calculated using the Kaplan-Meier method and predictors of drug retention were determined by Cox proportional hazard model. …
Muc1 And Muc5ac Implication In Tunisian Colorectal Cancer Patients, Meriam Hazgui, Marwa Weslati, Rahma Boughriba, Donia Ounissi, Dhouha Bacha, Saadia Bouraoui
Muc1 And Muc5ac Implication In Tunisian Colorectal Cancer Patients, Meriam Hazgui, Marwa Weslati, Rahma Boughriba, Donia Ounissi, Dhouha Bacha, Saadia Bouraoui
Turkish Journal of Medical Sciences
Background/aim: Mucins, such as MUC1 and MUC5AC, are known for their protective and moisturizing role in intestinal epithelium. Their expression is tightly controlled given their essential role in normal tissue homeostasis, whereas their deregulation leads to chronic inflammation, and even cancer. This study aimed to assess the expression profiles of MUC1 and MUC5AC and their implications in colorectal carcinogenesis. Materials and methods: A retrospective study of 202 patients who underwent colorectal cancer (CRC) surgery was conducted. The expression of MUC1 and MUC5AC was investigated by immunohistochemistry and reverse-transcription polymerase chain reaction (RT-PCR). Statistical analysis of mucin expression pattern, as well …
The Prognostic Value Of Serum Levels Of A Proliferation-Inducing Ligand (April) Intreatment-Naïve Patients With Chronic Lymphocytic Leukemia, Si̇nem Ni̇hal Esatoğlu, Di̇lek Keski̇n, Ahmet Emre Eşkazan, Tuğrul Elverdi̇, Ayşe Sali̇hoğlu, Muhli̇s Cem Ar, Şeni̇z Öngören, Zafer Başlar, Yildiz Aydin, Hafi̇ze Uzun, Teoman Soysal
The Prognostic Value Of Serum Levels Of A Proliferation-Inducing Ligand (April) Intreatment-Naïve Patients With Chronic Lymphocytic Leukemia, Si̇nem Ni̇hal Esatoğlu, Di̇lek Keski̇n, Ahmet Emre Eşkazan, Tuğrul Elverdi̇, Ayşe Sali̇hoğlu, Muhli̇s Cem Ar, Şeni̇z Öngören, Zafer Başlar, Yildiz Aydin, Hafi̇ze Uzun, Teoman Soysal
Turkish Journal of Medical Sciences
Background/aim: A proliferation-inducing ligand (APRIL) has been investigated as a prognostic marker in chronic lymphocytic leukemia (CLL) patients. However, there is no cut-off level for serum APRIL (sAPRIL) levels that predict time to treatment in CLL patients. Materials and methods: Between May and December 2012, 94 consecutive CLL patients and 25 healthy controls were assessed. sAPRIL levels were measured by ELISA. Demographic data and prognostic markers were obtained from the patients' files. Treatment-naïve patients were followed up for 6.5 years for any treatment need. Results: Patients were divided into 3 groups: Treatment-naïve (n = 47), chemotherapy receiving (n = 25), …
Assessment Of St2 And Reg3a Levels In Patients With Acute Graft-Versus-Host Disease Afterallogeneic Hematopoietic Stem Cell Transplantation, Eli̇fcan Aladağ Karakulak, Haluk Demi̇roğlu, Ümi̇t Yavuz Malkan, Ümi̇t Akman, Hakan Göker, Yahya Büyükaşik
Assessment Of St2 And Reg3a Levels In Patients With Acute Graft-Versus-Host Disease Afterallogeneic Hematopoietic Stem Cell Transplantation, Eli̇fcan Aladağ Karakulak, Haluk Demi̇roğlu, Ümi̇t Yavuz Malkan, Ümi̇t Akman, Hakan Göker, Yahya Büyükaşik
Turkish Journal of Medical Sciences
Background/aim: Graft-versus-host disease (GVHD) is a crucial complication leading to significant morbidity and mortality allogeneic hematopoietic stem cell transplantation which occurs in approximately half of the transplant recipients. Suppression of tumorigenicity 2 (ST2) and regenerating islet-derived 3-alpha(Reg3a) might be important biomarkers to predict acute GVHD. Materials and methods: In the present study, blood samples were collected from 17 patients with acute GVHD and 12 control patients after allogeneic stem cell transplantation. ST2 and Reg3a were measured in plasma samples compared in patients with acute GVHD and the controls. Results: Median age of the study population was 42 years (range 19-49). …
Lycopene Sensitizes The Cervical Cancer Cells To Cisplatin Via Targeting Nuclear Factorkappab (Nf-��B) Pathway, Oktay Hali̇t Aktepe, Taha Koray Şahi̇n, Gürkan Güner, Zafer Arik, Şuayi̇b Yalçin
Lycopene Sensitizes The Cervical Cancer Cells To Cisplatin Via Targeting Nuclear Factorkappab (Nf-��B) Pathway, Oktay Hali̇t Aktepe, Taha Koray Şahi̇n, Gürkan Güner, Zafer Arik, Şuayi̇b Yalçin
Turkish Journal of Medical Sciences
Background/aim: Lycopene is associated with anticancer effects in various tumor types. However, the exact underlying mechanisms of action of lycopene in human cervical cancer remain to be determined. This study aimed to determine anticancer efficacy and mechanism of lycopene in human cervical carcinoma (HeLa) cells. Materials and methods: HeLa cells were treated with cisplatin (1 μM) alone, lycopene (10 μM) alone, and in combination for 72 h. The cell viability of HeLa cells was assessed via MTS assay. Western blot was used to analyze the expression levels of the nuclear factor-kappa B (NF-ΚB), B-cell-associated X protein (Bax), nuclear factor erythroid …
Stereological And Histopathological Evaluation Of The Effect Of Thymoquinone Onperidural Fibrosis Following Laminectomy In Rats, Dursun Türköz, Aytaç Türköz, Mehmet Emi̇n Önger, Eni̇s Kuruoğlu
Stereological And Histopathological Evaluation Of The Effect Of Thymoquinone Onperidural Fibrosis Following Laminectomy In Rats, Dursun Türköz, Aytaç Türköz, Mehmet Emi̇n Önger, Eni̇s Kuruoğlu
Turkish Journal of Medical Sciences
Background/aim: This study's aim was to investigate the effects of thymoquinone, which is the essential bioactive component of the volatile oil of Nigella sativa on the peridural fibrosis in rats following laminectomy. Materials and methods: Twenty female Wistar Albino rats were used in our study. The rats were randomly divided into 2 groups: Sham and Surgery + Thymoquinone. Both groups underwent laminectomy at L1 under general anesthesia. The Sham group was not subjected to any drug application. The 2nd group was treated with intraperitoneal 10-mg/kg thymoquinone once per day for a period of 28 days, following the same surgical procedure. …
Investigation Of Performances Of Commercial Diesel Oxidation Catalysts For Co, C3h6, And No Oxidation, Hande Güneş, Deni̇z Şanli Yildiz, Hüseyi̇n Barkin Özener, Gökhan Hi̇sar, Selmi̇ Eri̇m Bozbağ, Can Erkey
Investigation Of Performances Of Commercial Diesel Oxidation Catalysts For Co, C3h6, And No Oxidation, Hande Güneş, Deni̇z Şanli Yildiz, Hüseyi̇n Barkin Özener, Gökhan Hi̇sar, Selmi̇ Eri̇m Bozbağ, Can Erkey
Turkish Journal of Chemistry
Four commercial monolithic diesel oxidation catalysts (DOCs) with two different platinum group metal (PGM) loadings and Pt:Pd ratios of 1:0, 2:1, 3:1 (w/w) were investigated systematically for CO, C3H6, and NO oxidation, CO-C3H6 co-oxidation, and CO-C3H6-NO oxidation reactions via transient activity measurements in a simulated diesel engine exhaust environment. As PGM loading increased, light-off curves shifted to lower temperatures for individual and co-oxidation reactions of CO and C3H6. CO and C3H6 were observed to inhibit the oxidation of themselves and each other. Addition of Pd to Pt was found to enhance CO and C3H6 oxidation performance of the catalysts while …
Novel Mixed Ligand Coordination Compounds Of Some Rare Earth Metal Cations Containing Acesulfamato/N,N-Diethylnicotinamide, Leri̇man Zeybel, Dursun Ali̇ Köse
Novel Mixed Ligand Coordination Compounds Of Some Rare Earth Metal Cations Containing Acesulfamato/N,N-Diethylnicotinamide, Leri̇man Zeybel, Dursun Ali̇ Köse
Turkish Journal of Chemistry
The mixed ligand coordination compounds containing acesulfamato and N,N-diethylnicotinamide biomolecules of some rare earth metal cations (Eu3+, Tb3+, Ho3+, Er3+ and Yb3+) were synthesized, and their structural properties were investigated. Possible structural formulas have been proposed by determining the chemical composition of molecules (elemental analysis), binding properties (infrared spectroscopy, mass analysis, solid-state UV-vis spectroscopy), thermal degradation properties (TGA / DTA curves). Based on the data collected, it is suggested that rare earth metal cations with a 3+ oxidation state have sextet coordination. The geometries of the structures were thought to be distorted octahedral. The charge balance of the coordination sphere …
Binding Of Permanganate Anion To Pentaammineazidocobalt(Iii) Cation In Solution And Solid Phases: Synthesis, Characterization, X-Ray Structure, And Genotoxic Effects Of [Co(Nh3)5n3](Mno4)2•H2o, Ritu Bala, Jinkwon Kim, Vinit Prakash
Binding Of Permanganate Anion To Pentaammineazidocobalt(Iii) Cation In Solution And Solid Phases: Synthesis, Characterization, X-Ray Structure, And Genotoxic Effects Of [Co(Nh3)5n3](Mno4)2•H2o, Ritu Bala, Jinkwon Kim, Vinit Prakash
Turkish Journal of Chemistry
A pentaammineazidocobalt(III) complex, [Co(NH3)5N3](MnO4)2XH2O has been synthesized by an one-pot synthesis method. It was characterized by studies such as infrared (IR) and UV-visible spectroscopy. The single crystal X-ray structure analysis revealed that the title complex crystallizes in space group Cc. The cobalt center is six coordinated with slightly octahedral geometry. The supramolecular architecture is also formed by intermolecular N-H…O (anion and H2O) and Mn-O…O-H hydrogen bonds. The binding property of the cation, [Co(NH3)5N3]2+ with the anion, MnO4- has also been determined (in solution phase) with the help of UV-visible spectroscopic titrations. Further, the genotoxic effects of KMnO4, [Co(NH3)5N3]Cl2 and [Co(NH3)5N3](MnO4)2XH2O …
Fabrication And Characterization Of Enhanced Hydrazine Electrochemical Sensor Based On Gold Nanoparticles Decorated On The Vanadium Oxide, Ruthenium Oxide Nanomaterials, And Carbon Nanotubes Composites, Si̇bel Karaca, Süleyman Koçak
Fabrication And Characterization Of Enhanced Hydrazine Electrochemical Sensor Based On Gold Nanoparticles Decorated On The Vanadium Oxide, Ruthenium Oxide Nanomaterials, And Carbon Nanotubes Composites, Si̇bel Karaca, Süleyman Koçak
Turkish Journal of Chemistry
This work describes the synthesis of mixed oxide film of vanadium and ruthenium by pulsed deposition technique on multiwall carbon nanotubes and the decoration of gold nanoparticles on the mixed film. A ternary electrocatalyst has been developed for the electrochemical oxidation of hydrazine by combining two metal oxide mixtures with Au nanoparticles. Surface morphology and chemical composition of the electrode have been examined with SEM, EDX, HRTEM, EIS, and XRD. The peak current of hydrazine increased 9 times at the AuNPs/(VOx-RuOx)/CNT/GCE compared to the bare GCE, and the peak potential shifted to negative 848 mV. Linear sweep voltammetry (LSV) and …
Catalytic, Theoretical, And Biological Investigation Of An Enzyme Mimic Model, Gülci̇han Gülseren
Catalytic, Theoretical, And Biological Investigation Of An Enzyme Mimic Model, Gülci̇han Gülseren
Turkish Journal of Chemistry
Artificial catalyst studies were always stayed at the kinetics investigation level, in this work bioactivity of designed catalyst were shown by the induction of biomineralization of the cells, indicating the possible use of enzyme mimics for biological applications. The development of artificial enzymes is a continuous quest for the development of tailored catalysts with improved activity and stability. Understanding the catalytic mechanism is a replaceable step for catalytic studies and artificial enzyme mimics provide an alternative way for catalysis and a better understanding of catalytic pathways at the same time. Here we designed an artificial catalyst model by decorating peptide …
Low Loaded Pt-Co Catalyst Surfaces Optimized By Magnetron Sputtering Sequentialdeposition Technique For Pem Fuel Cell Applications: Physical And Electrochemicalanalysis On Carbon Paper Support, Osman Öztürk, Aydin Haşi̇moğlu, Oğuz Kaan Özdemi̇r, İnci̇ Karaaslan, Ali̇ Şems Ahsen
Low Loaded Pt-Co Catalyst Surfaces Optimized By Magnetron Sputtering Sequentialdeposition Technique For Pem Fuel Cell Applications: Physical And Electrochemicalanalysis On Carbon Paper Support, Osman Öztürk, Aydin Haşi̇moğlu, Oğuz Kaan Özdemi̇r, İnci̇ Karaaslan, Ali̇ Şems Ahsen
Turkish Journal of Chemistry
A series of thin Pt-Co films with different metal ratios were deposited by using the sequential cosputtering directly on a commercial hydrophobic carbon paper substrate at room temperature and in ultra-high vacuum (UHV) conditions. Their electrocatalytic properties toward the oxygen reduction reaction were investigated in 0.5 M H2SO4 solution by means of cyclic voltammetry (CV) and linear sweep voltammetry (LSV) on rotating disc electrode (RDE). The results showed that Pt particles, deposited by dc-magnetron gun, surround the large Co-clusters deposited by rf-magnetron gun. In addition, the increase of Co content led to an increase in the electrochemical active surface area …
Photocatalytic Decomposition Of Textile Dyestuffs By Photosensitive Metal Oxide Catalysts, Esra Yeli̇z Altun, Zehra Tuba Şi̇şmanoğlu, Güli̇n Selda Pozan Soylu
Photocatalytic Decomposition Of Textile Dyestuffs By Photosensitive Metal Oxide Catalysts, Esra Yeli̇z Altun, Zehra Tuba Şi̇şmanoğlu, Güli̇n Selda Pozan Soylu
Turkish Journal of Chemistry
Textile azo dyes are one of the pollutants in waste water that adversely affect human and environmental health. Removal of these chemicals from wastewater is important for eco-system and human health. In this study, Bi2O3 nanoflakes and ZnO were synthesized by the co-precipitation method. Adsorption and photocatalytic degradation reactions were carried out to remove dyes (Victoria blue (VB) and Malachite green (MG)) from wastewater with the photocatalysts. In order to improve the activity of catalysts, cetyltrimethylammoniumbromide (CTAB) was added as a surfactant to pure oxide structures, and Bi2O3-CTAB and ZnO-CTAB catalysts were prepared. The structural and morphological properties of these …
Chemical Composition And Biological Activities Of Essential Oils Of Two New Chemotypes Of Glebionis Cass., Hüseyi̇n Servi̇
Chemical Composition And Biological Activities Of Essential Oils Of Two New Chemotypes Of Glebionis Cass., Hüseyi̇n Servi̇
Turkish Journal of Chemistry
This paper includes the result of the first study of the chemical composition, antioxidant, antiinflammatory, and antidiabetic activities of the essential oils of Glebionis coronaria (L.) Cass. ex Spach and Glebionis segetum (L.) Fourr. from Turkey. In the current study, nine and twenty-eight constituents were determined in the essential oils of aerial parts of G. coronaria (GCE) (92.1%) and G. segetum (GSE) (90.0%), respectively. The main components were capillin (65.9%) in GCE, capillene (53.4%) in GSE. The essential oil compositions were evaluated and compared with previous researches. In the current study, the plants are classified as chemotypes of Glebionis species. …
Enhancement Of Dispersion Stability Of Inorganic Additives Via Poly(Sodium-4-Styrenesulfonate) Treatment Geared To Hydrogel Applications, Fi̇li̇z Boran, Merve Okutan
Enhancement Of Dispersion Stability Of Inorganic Additives Via Poly(Sodium-4-Styrenesulfonate) Treatment Geared To Hydrogel Applications, Fi̇li̇z Boran, Merve Okutan
Turkish Journal of Chemistry
This study reports the preparation of poly(sodium-4-styrene sulfonate) (PSS) treated bentonite and clinoptilolite to prevent the agglomeration and sedimentation of these inorganic fillers during the preparation of hydrogel. For this purpose PSS treated fillers were prepared by using various techniques (dip and dry, hydrothermal, one-step ball milling and ultrasonication methods). The most suitable technique for preparing these PSS treated inorganic fillers (abbreviated as BP-dip and CP-dip) was the dip and dry method. BP-dip and CP-dip based polyvinyl alcohol/polyvinylpyrrolidone (PVA/PVP) composite hydrogels were prepared using the freeze/ thawing method after the addition of one of BP-dip and CP-dip inorganic fillers in …
Poly(N-Vinylimidazole): A Biocompatible And Biodegradable Functional Polymer, Metal-Free, And Highly Recyclable Heterogeneous Catalyst For The Mechanochemical Synthesis Of Oximes, Hayedeh Gorjian, Hoda Fahim, Nader Ghaffari Khaligh
Poly(N-Vinylimidazole): A Biocompatible And Biodegradable Functional Polymer, Metal-Free, And Highly Recyclable Heterogeneous Catalyst For The Mechanochemical Synthesis Of Oximes, Hayedeh Gorjian, Hoda Fahim, Nader Ghaffari Khaligh
Turkish Journal of Chemistry
The catalytic activity of poly(N-vinylimidazole), a biocompatible and biodegradable synthetic functional polymer, was investigated for the synthesis of oximes as an efficient, halogen-free, and reusable heterogeneous catalyst. The corresponding oximes were afforded in high to excellent yields at room temperature and in short times using the planetary ball mill technique. Some merits, such as the short reaction times and good yields for poorly active carbonyl compounds, and avoiding toxic, expensive, metal-containing catalysts, and hazardous and flammable solvents, can be mentioned for the current catalytic synthesis of the oximes. Furthermore, the heterogeneous organocatalyst could be easily separated after the reaction, and …
A New Implicit-Explicit Local Differential Method For Boundary Value Problems, Hüseyi̇n Tunç, Murat Sari
A New Implicit-Explicit Local Differential Method For Boundary Value Problems, Hüseyi̇n Tunç, Murat Sari
Turkish Journal of Mathematics
In this study, an effective numerical method based on Taylor expansions is presented for boundary value problems. This method is arbitrary directional and called as implicit-explicit local differential transform method (IELDTM). With the completion of this study, a reliable numerical method is derived by optimizing the required degrees of freedom. It is shown that the order refinement procedure of the IELDTM does not affect the degrees of freedom. A priori error analysis of the current method is constructed and order conditions are presented in a detailed analysis. The theoretical order expectations are verified for nonlinear BVPs. Stability of the IELDTM …
Existence Of Nonnegative Solutions For Discrete Robin Boundary Value Problems With Sign-Changing Weight, Yan Zhu
Turkish Journal of Mathematics
In this paper,~we are concerned with the following discrete problem first $$\left\{ \begin{array}{ll} -\Delta^{2}u(t-1)=\lambda p(t)f(u(t)), &t\in[1,N-1]_{\mathbb{Z}},\\ \Delta u(0)=u(N)=0,\\ \end{array} \right. $$ where $N>2$~is an integer,~$\lambda>0$~is a parameter,~$p:[1,N-1]_{\mathbb{Z}}\rightarrow\mathbb{R}$~is a sign-changing function,~$f:[0,+\infty)\rightarrow[0,+\infty)$~is a continuous and nondecreasing function.~$\Delta u(t)=u(t+1)-u(t)$,~$\Delta^{2}u(t)=\Delta(\Delta u(t))$.~By using the iterative method and Schauder's fixed point theorem,~we will show the existence of nonnegative solutions to the above problem. Furthermore, we obtain the existence of nonnegative solutions for discrete Robin systems with indefinite weights.
On The Spectral And Scattering Properties Of Eigenparameter Dependent Discrete Impulsive Sturm-Liouville Equations, Yelda Aygar Küçükevci̇li̇oğlu, Elgi̇z Bayram, Güher Gülçehre Özbey
On The Spectral And Scattering Properties Of Eigenparameter Dependent Discrete Impulsive Sturm-Liouville Equations, Yelda Aygar Küçükevci̇li̇oğlu, Elgi̇z Bayram, Güher Gülçehre Özbey
Turkish Journal of Mathematics
This work develops scattering and spectral analysis of a discrete impulsive Sturm-Liouville equation with spectral parameter in boundary condition. Giving the Jost solution and scattering solutions of this problem, we find scattering function of the problem. Discussing the properties of scattering function, scattering solutions, and asymptotic behavior of the Jost solution, we find the Green function, resolvent operator, continuous and point spectrum of the problem. Finally, we give an example in which the main results are made explicit.
Soft $\Beta$-Rough Sets And Their Application To Determine Covid-19, Mostafa K. El Bably, Abd El Fattah A. El Atik
Soft $\Beta$-Rough Sets And Their Application To Determine Covid-19, Mostafa K. El Bably, Abd El Fattah A. El Atik
Turkish Journal of Mathematics
Soft rough set theory has been presented as a basic mathematical model for decision-making for many real-life data. However, soft rough sets are based on a possible fusion of rough sets and soft sets which were proposed by Feng et al. [20]. The main contribution of the present article is to introduce a modification and a generalization for Feng's approximations, namely, soft $\beta$-rough approximations, and some of their properties will be studied. A comparison between the suggested approximations and the previous one [20] will be discussed. Some examples are prepared to display the validness of these proposals. Finally, we put …
On The Local And Global Stability Of An Sirs Epidemic Model With Logistic Growth And Information Intervention, İrem Çay
Turkish Journal of Mathematics
In this study, we investigate an susceptible-infected-recovered-susceptible (SIRS) epidemic model with logistic growth and information intervention. Firstly, the basic reproduction number $R_0$ is defined and the main results are given in terms of local stability. Then, sufficient conditions for the global stability of endemic equilibrium are obtained. Finally, some numerical simulations are given to validate our theoretical conclusions.
A Performance Assessment Of An Hdg Method For Second-Order Fredholm Integro-Differential Equation: Existence-Uniqueness And Approximation, Mehmet Fati̇h Karaaslan
A Performance Assessment Of An Hdg Method For Second-Order Fredholm Integro-Differential Equation: Existence-Uniqueness And Approximation, Mehmet Fati̇h Karaaslan
Turkish Journal of Mathematics
In this paper, we obtain the existence--uniqueness of solution to the second-order linear Fredholm integro-differential equation (FIDE) with Dirichlet boundary condition by hybridizable discontinuous Galerkin (HDG) method. A key property of these methods is to eliminate all internal degrees of freedom and to construct a linear system that only includes globally coupled unknowns at the element interfaces. After designing and implementing HDG algorithm, we provide some necessary and sufficient conditions based on the stabilization parameter and kernel function to guarantee the existence-uniqueness of the approximate solution. Then, some numerical examples are carried out to assess the performance of the present …
On Lyapunov-Type Inequalities For $(N+1)$St Order Nonlinear Differential Equations With The Anti-Periodic Boundary Conditions, Mustafa Fahri̇ Aktaş
On Lyapunov-Type Inequalities For $(N+1)$St Order Nonlinear Differential Equations With The Anti-Periodic Boundary Conditions, Mustafa Fahri̇ Aktaş
Turkish Journal of Mathematics
In this paper, we establish new Lyapunov-type inequalities for $\left(n+1\right)$st order nonlinear differential equation including $p$-relativistic operator and $q$-prescribed curvature operator under the antiperiodic boundary conditions.
On A Coupled Caputo Conformable System Of Pantograph Problems, Sabri T. M. Thabet, Sina Etemad, Shahram Rezapour
On A Coupled Caputo Conformable System Of Pantograph Problems, Sabri T. M. Thabet, Sina Etemad, Shahram Rezapour
Turkish Journal of Mathematics
Our fundamental purpose in the present manuscript is to explore existence and uniqueness criteria for a new coupled Caputo conformable system of pantograph problems in which for the first time, the given boundary conditions are formulated in the Riemann-Liouville conformable framework. To reach the mentioned aims, we utilize different analytical techniques in which some fixed point results play a vital role. In the final part, a simulative example is designed to cover the applicability aspects of theoretical findings available in this research manuscript from a numerical point of view.
Infinitesimal Bending Of Dna Helices, Miroslav Maksimovic, Ljubica Velimirovic, Marija Najdanovic
Infinitesimal Bending Of Dna Helices, Miroslav Maksimovic, Ljubica Velimirovic, Marija Najdanovic
Turkish Journal of Mathematics
The mathematics of DNA molecules is often studied as a double helix model. This paper focuses on the modelling of infinitesimal bending of DNA helices. The paper checks the flexibility of DNA molecule, i.e. the flexibility of double helix in infinitesimal bending theory. Actually, first, we find infinitesimal bending field of an arbitrary curve on the helicoid, that leaves bent curves on the helicoid, and show that helix bending on the helicoid is not possible. Finally, we deal with the infinitesimal bending of helicoid, using PDEs. Visualization of infinitesimal bending was done in Mathematica.
A Rich Fading Biocultural Diversity?A Review Of Traditional Herbal Teas Used By Minorities In The Balkans, Muhammad Abdul Aziz, Andrea Pieroni, Syed Abidullah, Anely Nedelcheva
A Rich Fading Biocultural Diversity?A Review Of Traditional Herbal Teas Used By Minorities In The Balkans, Muhammad Abdul Aziz, Andrea Pieroni, Syed Abidullah, Anely Nedelcheva
Turkish Journal of Botany
Ethnobotanical studies focusing on medicinal plant ingredients have always been conducted with the aim of protecting the local ecological knowledge (LEK) of these natural resources. In the globalized world, the rapid loss of biodiversity and cultural and linguistic homogenization have threatened the survival of the planet, together with leading us towards an extinction crisis. In this extreme situation, LEK is also facing serious challenges, especially that of minorities where the pressure is manifold. A number of studies have been carried out among minority groups in recent times, and scientists are attempting to devise solid policy recommendations to celebrate their LEK …