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Health Impacts And Medical Assistance After Libyan Flood Disaster: Emergency Medical Teams’ Responses, Hakan Güner, Okan Maden, Muhammed Saltuk Deni̇z, Kerem Dost Bi̇lmez, Şükrü Yorulmaz, Mehmet Enes Gökler

Turkish Journal of Medical Sciences

Background/aim: Floods are the most frequent natural disasters and pose direct and indirect health risks, some well-documented and others poorly understood. Epidemiological studies help bridge these gaps and guide effective public health responses.In September 2023, Storm Daniel caused severe flooding in Libya, damaging infrastructure, including healthcare facilities. The disaster affected 250,000 people, displaced 48,000, and claimed 15,000 lives, making it the second deadliest natural disaster of the year. This study aims to assess the characteristics of flood-affected patients to improve disaster preparedness.

Materials and methods: This descriptive study examined disaster victims who visited three clinics established as part of an …

Development Study Of Scientific Competence And Activity Scale In Medical Faculty Research Assistants, Cemal Koçak, Hande Güverci̇n, Ecem Esen, Meltem Çöl

Turkish Journal of Medical Sciences

Background/aim: One mission of medical faculties is training scientists equipped with the necessary knowledge, skills, attitudes, who can evaluate the scientific research. The aim was to develop a scale for evaluating the level of scientific competence and activity in research assistants.

Materials and methods: The study is a methodological study, conducted in October 2023-May 2024 with 299 research assistants working at X University Faculty of Medicine. The reliability was assessed by item-total correlation and Cronbach-alpha coefficient; construct validity was assessed by EFA. In EFA, principal component analysis, Varimax rotation were used. KMO and Barttlet test p value were calculated. Groups …

Forensic Identification Using Airdna: A Preliminary Study On The Collection, Isolation, Amplification And Sequencing Of Human Dna From Air Samples, Sitki Tiplamaz, Zehra Ömeroğlu Ulu, Bestami̇ Çolak, Hizir Asliyüksek, Fi̇kretti̇n Şahi̇n

Turkish Journal of Medical Sciences

Background/aim: Humans continually release skin cells and DNA fragments into the air. This DNA can either remain airborne or drop onto surfaces as indoor dust. This study investigates the collection, isolation, amplification, and sequencing of human DNA from air samples, focusing on both nuclear DNA and mitochondrial DNA.

Materials and methods: This study was conducted in a 15 m3 room and a meeting room, where air samples were systematically collected and filtered using a vacuum device equipped with various sterile filters. The rigorous protocols were implemented to prevent contamination throughout the process. Thirteen air samples were processed in this research, …

Vitamin D Deficiency And Surgical Cellulose Mimicking Parathyroid Adenomaafter Initial Parathyroidectomy, Mustafa Şahi̇n, Volkan Genç, Koray Ceyhan, Demet Corapcioglu

Turkish Journal of Medical Sciences

Background/aim: Primary hyperparathyroidism is a condition characterized by an excessive production of parathyroid hormone primarily resulting from the presence of an adenoma or hyperplasia of the parathyroid glands.

Materials and methods: A 45-year-old woman who had previously experienced high levels of calcium in her blood and abnormally elevated parathyroid hormone levels underwent surgical removal of the left parathyroid gland. Following surgery, she exhibited high levels of parathyroid hormone along with normalized calcium levels and persistent fatigue. Ultrasound imaging showed a hypoechoic mass on the left side, which was initially considered to be a recurrent parathyroid tumor.

Results: A comprehensive assessment, …

Evaluation And Validation Of 3d-Printed Anatomical Urinary System Model And Virtual Reality Rirs Simulators In Rirs Training: A Comparative Study, Mehmet Ezer, Tahsi̇n Batuhan Aydoğan, Lazaros Tzelves, Andreas Skolarikos, Mehmet Uslu, Kemal Sarica, Emre Huri̇

Turkish Journal of Medical Sciences

Background/aim: This study evaluates the use of a 3D-printed anatomical urinary system model (3D-AUSM) and a Virtual Reality RIRS Simulator (VRRS), for training in RIRS, based on real user feedback.

Materials and methods: The 3D-AUSM was created using cadaver CT and MRI scans, and the data was transferred to a VR environment for simulation. A total of 43 inexperienced urology trainees participated in the theoretical phase of the RIRS training program. Of these, 32 trainees (Group T) who passed a proficiency exam proceeded to the hands-on training phase with the 3D-AUSM and VRRS models. Additionally, 17 experienced surgeons (Group S) …

Effects Of Lumbar Stabilization Exercises On Serum Biomarker Levels And Clinical Outcomes In Lumbar Disc Herniation: A Subgroup Analysis Of A Randomized Controlled Trial, Bi̇rgül Morkoç, Onur Aktan, Gamze Sönmez, Ebru Bodur, Jale Karakaya, Bayram Kaymak, Sevi̇l Bi̇lgi̇n

Turkish Journal of Medical Sciences

Background/aim: The aim of our study was to investigate the effectiveness of lumbar stabilization exercises on serum biomarker levels and clinical outcomes in lumbar disc herniation (LDH) patients with and without neurological deficit.

Materials and methods: 40 patients with neurological deficits (WND) and 34 patients without neurological deficits (WOND) diagnosed with LDH were included in this study. The patients WND and WOND were randomized into stabilization exercises (SE) and general exercises (GE) groups. Stabilization exercises or general exercises were applied for six weeks. Serum levels of tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β, IL-6, IL-4, beta-endorphin (BE), anandamide (AEA), and …

Medicolegal Evaluation Of Pediatric Patients With Injection Neuropathy, Hizir Asliyüksek, Caner Beşkoç, Ömer Faruk Şi̇mşeker, Ni̇han Hande Akçakaya, Adem Karbuz

Turkish Journal of Medical Sciences

Background/aim: Injection neuropathy (IN) is a rare but preventable form of iatrogenic nerve injury, particularly affecting the sciatic nerve when intramuscular injections are administered incorrectly. While IN is uncommon in high-income countries, it remains a sig- nificant public health issue in Türkiye, especially in pediatric populations. The aim of this study is to evaluate pediatric IN cases referred to the Council of Forensic Medicine and highlight medicolegal aspects to inform clinical and legal preventive strategies.

Materials and methods: We retrospectively analyzed 67 pediatric cases (age range: 1–17 years; mean age: 10.5 years; 57 boys, 10 girls) referred to the Council …

Histological And Histochemical Study Of The Salt Glands In Geese (Anser Anser): Are There Receptor Cells In Salt Glands?, Şahi̇n Aslan, Di̇lem Gülece Ermutlu, Serap İlhan Aksu, Serap Koral Taşçi, Turgay Deprem

Turkish Journal of Veterinary & Animal Sciences

The regulation of solutes occurs not through the skin but via salt glands located in the nose and kidneys in reptiles and birds. This study aimed to investigate and elucidate the histological structure of the salt glands in domestic geese, and to characterize their ducts and cellular components in detail.Crossmon’s triple staining technique, hematoxylin and eosin (H&E), periodic acid-Schiff (PAS), combined alcian blue, and Kluver– Barrera stains were used for the histological investigations.The outer surface of the organ was enclosed by connective tissue, and the capsule subdivided the tissue into bulbs. Nerve fibers and endings were observed within the capsule …

Soil Geochemistry Characteristics Of Bimodal-Mafic Type Vms Deposits In The Central Pontides: Importance Of Data Investigation In Exploration And Following Discovery, Buğra Çavdar, Kurtuluş Günay

Turkish Journal of Earth Sciences

Çangaldağ Metamorphic Complex is defined with low grade metamorphic equivalents of mafic to felsic intrusive and extrusives, clastics and volcanoclastics. The Au-Cu-Zn Say Yayla (deeply-seated; West Zone) and the Au-dominant Büyük Hill (gossan related; East Zone) deposits are classified as bimodal-mafic type VMS in that complex and they are hosted in the metafelsic ensimatic arc volcanics. These were investigated by soil samples developed over each mineralization to examine the soil characteristics with different textural features. A total of 274 soil samples were collected and they have been geochemically analysed and examined using various statistical methods. The results reveal that both …

Integrated Geochemical, Geoelectrical, And Uav-Based Methods For Analyzing The Güzelyalı Landslide (Çanakkale, Türkiye), Oya Erenoğlu, Emi̇n Ulugergerli̇, R. Cüneyt Erenoğlu, Abdullah Akbaş, Ahmet Evren Ergi̇nal

Turkish Journal of Earth Sciences

The number of reactivations increased in the Güzelyalı-Erenköy landslide area after 2013 in Çanakkale, Türkiye, where historical landslide activity has been recorded since 1875. This area is home to numerous summer residences and experiences ongoing slow-moving landslide activity along a 400-m-long slope, extending from the heavily trafficked Çanakkale-İzmir highway to the coastline. In this study, the nature of the reactivations was evaluated by considering the conditioning and triggering factors that contributed to the landslide. The evaluation was based on geochemical analyses, field observations, geoelectric measurements, and unmanned aerial vehicle (UAV) data. The results revealed that the sliding occurred along a …

Apatite Chemistry From The Xv Ioa Deposit, The Bafq–Saqand Metallogenic Province (Bsmp), Central Iran: Constrains On The Genesis Of Ioa Deposits, Sakine Amraei, Majid Ghasemi Siani, Mohammad Yazdi, Liang Qiu, Chang–Zhi Wu, Minghua Ren, Shahrokh Rajabpour

Turkish Journal of Earth Sciences

In this study, we present petrographical and microanalytical (EPMA, LA–ICP–MS) results of apatites associated with Fe–Ti±P mineralization in the XV deposit in the BSMP. Apatite is predominantly observed as subhedral to euhedral, homogeneous grains, with no zoning or inclusions. Geochemically, apatite is fluorapatite of magmatic origin, with Cl/OH and Cl/F ratios of <0.05 and 0.01 to 0.07, respectively. Apatites from XV and other IOA deposits in the BSMP display a high F/Cl ratio, which is likely the main characteristic of IOA–type deposits such as the Kiruna-type deposit. Apatites from both rock types (gabbro and pyroxenite) exhibit similar rare earth elements (REEs) and multitrace element patterns, indicative of a shared origin. The highly light rare earth elements (LREEs)–enriched pattern in chondrite–normalized fractionation trends, along with positive Eu and slight negative Ce anomalies, as well the high (La/Sm)N and (La/Yb)N ratios of XV apatite, further corroborates the magmatic genesis of fluorapatite. The Eu/Eu* and Ce/Ce* ratios in XV rocks imply a high oxidation condition, as well as other IOA deposits in BSMP. The sulfur content is less than 1 wt% and shows a positive correlation with SiO2, implying coupled dissolution–reprecipitation of primary fluorapatite. Considering the geological setting of XV and other IOA deposits in the BSMP, the parental magma(s) appear to have originated from oxidizing Fe-Ti±P-rich magma(s), likely formed within an extensional postcollisional setting, influenced by the Proto–Tethys and Central Iranian Microcontinent (CIMC) convergence events.

First Record Of Scyphocrinoids In Türkiye And Recognition Of The Silurian/Devonian Boundary Interval (Halevikdere Section, Eastern Taurides), Eberhard Schindler, Reimund Haude, Mehmet Namik Yalçin, Rainer Brocke, Ati̇ke Nazi̇k, Emine Şeker Zor, Volker Wilde, Achim Wehrmann

Turkish Journal of Earth Sciences

During the Silurian/Devonian (S/D) boundary interval, scyphocrinoids (Crinoidea, Echinodermata) flourished on a global scale. The first record of scyphocrinoids from Türkiye, especially represented by their bulbuous loboliths, is now described from the Halevikdere Section in the Eastern Taurides. The Devonian part of the section is more than 1300 m thick and covers a time span from the S/D boundary interval to the Late Devonian (Famennian). It consists mainly of fine-grained to sandy siliciclastics, event-driven conglomerates/fanglomerates and biogenic carbonates deposited in deep shelf to shallow-water coastal settings. The S/D boundary interval was measured and studied in great detail. The dominant lithology …

The Quaternary Fluvial-Lacustrine System In The Akarçay Basin (Sw Anatolia): Depositional Environments And Paleoclimatic Interpretation, Koray Aktürk, Sevi̇nç Kapan

Turkish Journal of Earth Sciences

The Akarçay Closed Basin, located in southwest Anatolia, contains deformed formations and the drying Akşehir and Eber lakes. This study aimed to interpret the paleoenvironmental and paleoclimatic conditions of the Akşehir and Eber lakes, which are reported to have been connected during the Pleistocene. Based on sedimentological and mineralogical data, three different depositional subenvironments were defined, corresponding to the formation and development stages of the lake. Sedimentary facies analysis of the Pleistocene deposits in the basin revealed the following facies associations, listed from bottom to top: 1) an alluvial fan and fluvial facies association, representing the formation stage of the …

Formation Of Holocene Paleosols In A Relict Sand Dune Sequence At Kıyıköy, Türkiye, Ahmet Evren Ergi̇nal, Mustafa Bozcu, Nuretti̇n Yakupoğlu, Abdullah Akbaş, Hakan Kaya, İsmai̇l Onur Tunç

Turkish Journal of Earth Sciences

The paleoclimatic indicators from a relict dune and paleosol sequence observed south of Kıyıköy Port, NW Türkiye, provide insights into the variable paleoclimatic conditions in the western Black Sea coastal zone over the last 4700 yrs BP. The relict dune- paleosol sequence consists of reddish-brown coarse sands with abundant shells and overlying paleosol. Radiocarbon dating of Donax trunculus shells collected from the lowest part of the relict dune revealed the onset of sand deposition 4689 ± 123 yrs ago. The dark-colored paleosol layer, with an Rb/Sr ratio of 0.008, yielded an age of 287 ± 32 yrs cal BP. These …

U-Pb Calcite Geochronology, Epr, Geochemistry, And C-O-Sr Isotopes Of Africanomarbles In The Seferihisar (İzmir, Türkiye) U-Pb Calcite Geochronology, Epr, Geochemistry, And C-O-Sr Isotopes Of Africano Marbles In The Seferihisar (İzmir, Türkiye), Fatma Şi̇şman Tükel, Namik Aysal, İpek Deni̇z Yildirim, Marcel Guillong, Tonguç Uysal, Si̇nan Öngen, Emre Erdem

Turkish Journal of Earth Sciences

The Africano marbles (Africano Verde and Bigio Africano) extracted from the region of Sığacık (ancient Teos) region and its surroundings were widely used and even traded in construction and decorative items throughout the Roman period due to their brecciated and colourful appearance. There are two different types of Africano marble, the first consisting of marble breccias embedded in a dark matrix. In this type, the marble breccias show micritic, microsparitic, and sometimes sparitic textures formed by coarse-grained calcite, while the dark matrix consists of chlorite and/or serpentine minerals. The second type is Bigio Africano, which consists of grey-blue homogeneous limestones, …

Resource Allocation For Downlink Hybrid Noma With Nonideal Circuit Power Consumption, İlke Altin, Mehmet Akar

Turkish Journal of Electrical Engineering and Computer Sciences

This article studies the latency-constrained downlink resource allocation problem with nonideal circuit power consumption, focusing on the total energy consumption of the base station and the users. First, an optimal downlink Hybrid Non-Orthogonal Multiple Access (H-NOMA) scheme for two users is proposed which gives the optimal time and power allocation. Then, we extend the H-NOMA idea to multiple users by combining it with Orthogonal Frequency Domain Multiple Access (OFDMA) and allocate subchannels utilizing the novel Bootstrapped Total-Reward Exchange Stable (B-TES) algorithm. Afterward, via simulations, we show that the H-NOMA method outperforms Orthogonal Multiple Access (OMA) and Non-Orthogonal Multiple Access (NOMA) …

Enhanced Cuffless Blood Pressure Estimation Using Ecg And Ppg Signals: A Hybrid Approach With Windkessel, Arima, And Lstm, Piyush Mahajan, Amit Kaul

Turkish Journal of Electrical Engineering and Computer Sciences

Accurate blood pressure (BP) estimation is essential for the monitoring and management of cardiovascular diseases. This study presents a hybrid model for cuffless BP estimation using electrocardiogram (ECG) and photoplethysmogram (PPG) signals. The model incorporates features from time-domain, frequency-domain, and model-based approaches, including the Windkessel model, AutoRegressive Integrated Moving Average (ARIMA), and Long Short-Term Memory (LSTM) networks. To enhance performance, feature selection and reduction techniques such as Minimum Redundancy Maximum Relevance (MRMR) and autoencoders were employed. Additionally, model ensemble strategies, including average and weighted average modes, were utilized to combine the predictions of different models. The proposed method demonstrated superior …

Design And Optimization Of Low-Loss, High-Gain Metamaterial-Based Log-Periodic Dipole Array Antenna For Full Ka-Band Coverage, Mohamed El Moniar, Ahmed Abd El Hady, Yasser Ismail, Nihal Areed

Turkish Journal of Electrical Engineering and Computer Sciences

This work describes a microstrip log-periodic dipole array (MLPDA) antenna that uses metamaterials and operates across the whole Ka-band. The suggested MLPDA antenna layout provides a wide bandwidth with fewer dipole elements than traditional MLPDA antennas while maintaining the same resonance frequencies. To reduce size while covering a wide operational spectrum, the antenna design includes bending dipoles as radiating elements, as well as an incomplete ground plane. Furthermore, the proposed MLPDA antenna’s energy loss has been reduced while boosting its signal strength (gain) by inserting a metamaterial-based structure in front of it at a certain distance and on the same …

A Methodology For Nuclei Segmentation In H&E Images Using Efficientnetb7 Guided U-Net And Multiple Data Augmentation Strategies, Furkan Atlan, Emrah Hançer

Turkish Journal of Electrical Engineering and Computer Sciences

Automating nuclei segmentation in Hematoxylin and Eosin (H&E) stained images is crucial for advancing computational pathology. Despite significant research, challenges such as overlapping nuclei, varying scanner resolutions, and diverse nuclear morphologies continue to hinder segmentation accuracy. In this paper, we propose a deep-learning based methodology that integrates multiple data augmentation strategies with a U-Net architecture enhanced by the EfficientNetB7 encoder. To enhance generalization, we train the model using a combined dataset from MoNuSeg2018, CPM-17, and CoNSeP, exposing it to diverse staining techniques and tissue types. We then evaluate its robustness on the unseen CryoNuSeg dataset, which consists of fully annotated …

Harmonic Classification Of Different Lighting Technologies Using Empirical Mode Decomposition And Support Vector Machines, Ahmad Farid Abidin, Mohd Abdul Talib Mat Yusoh, Abdul Hafiz Kassim, Nik Hakimi Nik Ali

Turkish Journal of Electrical Engineering and Computer Sciences

The impact of excessive harmonic distortion on electrical distribution networks highlights the critical need to understand harmonics in different lighting technologies to detect sources of issues and their effects. The increasing prevalence of nonlinear loads in power systems has contributed to significant harmonic pollution, deteriorating power line quality. This paper aims to address this issue by focusing on power line frequency detection and the classification of lighting technologies, combining empirical mode decomposition (EMD) with the one-versus-one support vector machine (OVO-SVM) approach. EMD is utilized to analyze signals through intrinsic mode functions, preserving the signal’s characteristics while extracting features related to …

Karcı Fractional Artificial Neural Networks (Karcıfann): A New Artificial Neural Networks Model Without Learning Rate And Its Problems, Meral Karakurt, Hülya Saygili, Ali̇ Karci

Turkish Journal of Electrical Engineering and Computer Sciences

The learning rate parameter used in classical artificial neural networks (ANNs) designed with stochastic gradient descent causes problems such as failure to learn, getting stuck in local minima, memorization, and long training times (divergence problem). To address these issues, this paper proposes a novel ANN method that uses a fractional derivative instead of Newton’s derivative. This method is referred to as Karcı fractional ANN (KarcıFANN). In classical ANNs, the weight update is done by assigning the same constant value to the learning rate in each iteration or for a set number of iterations. In contrast, in KarcıFANNs, the weight update …

Molecular Phylogeny And Population Structure Of Eurygaster Integriceps (Hemiptera: Scutelleridae) In The Southeastern Anatolia Region Of Türkiye, Mehmet Sali̇h Özgökçe, Merve Doğaç, Hi̇lmi̇ Kara

Turkish Journal of Zoology

The aim of this study was to determine the identity and distribution of the sunn pest Eurygaster spp. and to quantify the population density in wheat fields across Southeastern Anatolia, Türkiye. A total of 309 samples were collected from 76 fields in 54 districts across all provinces within the study region, where wheat production is intensive. A combination of morphological and molecular techniques was employed to identify the collected specimens. Morphological identification was based on male genitalia, and PCR amplification of the COI mitochondrial gene region was used for DNA barcoding. Both morphological and molecular analyses confirmed that all collected …

Protein Composition Of The Foam Nest Of Rhacophorus Reinwardtii (Schlegel, 1840) (Anura: Rhacophoridae), With Notes On Breeding Sites Characteristics And Biomedical Applications, Muhammad Asyraf Rijalullah, Nia Kurniawan, Nia Kurnianingsih

Turkish Journal of Zoology

Rhacophorus reinwardtii is endemic to Java Island and is currently experiencing a population decline. Therefore, the sustainability of its offspring is important to prevent species extinction. Foam nest as a biosurfactant structure plays a crucial role as egg protection through major protein components function. However, studies on the functional proteins of rhacophoridae foam nests are limited. Thus, this study aims to uncover the protein-specific components and functions of the R. reinwardtii foam nest. Additionally, the characteristics of breeding sites, including abiotic factors, were also assessed. Total protein concentration of the R. reinwardtii foam nest was determined to be 747.7 μg/mL …

Unveiling The Physical Interaction Between Gsnor1 And Trx-H Isoforms, Anika Tabassum, Gary J. Loake

Turkish Journal of Botany

This study aims to investigate any possible interaction between two highly conserved regulators of cellular SNO levels: S-nitrosoglutathione reductase (GSNOR1) and thioredoxin (TRX). These two enzymes control global S-nitrosylation levels and thus impact the cellular redox state during immune responses. A mutant line (Δtrx1trx2sfa1) of Saccharomyces cerevisiae MaV203 strain was generated to explore this possibility rather than using a classical strain. We identified and characterized the physical interaction between GSNOR1 and Arabidopsis cytosolic h isoforms in a yeast two-hybrid screen. Out of the seven TRX isoforms, AtGSNOR1 displayed a high interaction with AtTRXh3, AtTRXh4, and AtTRXh5 (AtTRXh5>AtTRXh4 & AtTRXh3). …

Cover And Contents

Turkish Journal of Botany

No abstract provided.

Pointwise Slant Riemannian Maps From Almost Contact Metric Manifolds With Horizontal Reeb Vector Field ˆΞ, Ramazan Demi̇r, Cumali̇ Yildirim

Turkish Journal of Mathematics

This paper introduces the notion of pointwise slant Riemannian maps, which extend the concept of slant submanifolds, pointwise slant submanifolds, slant submersions, pointwise slant submersions, and slant Riemannian maps. These maps are defined from almost contact metric manifolds to Riemannian manifolds with horizontal Reeb vektor field . Furthermore, we present examples and investigate the fundamental properties of such maps. Also we explore the geometry of the foliations induced by pointwise slant Riemannian maps and establish decomposition theorems related to their existence.

On The Invariant Integration Of A Vector In Some Problems In Mechanics, Saad Bin Mansoor

Turkish Journal of Mathematics

Invariant integration of vectors and tensors over manifolds was introduced around fifty years ago by V.N. Folomeshkin, though the concept appears to not have attracted much attention among researchers. Although it is a sophisticated concept, the operation of the invariant integration of vectors is actually required to correctly solve some problems in mechanics. Two such problems are discussed in the present exposition, in the context of a two-dimensional Euclidean space covered by a polar coordinate system. The notion of invariant integration becomes necessary when the space is described without any reference to a Cartesian coordinate system.

The Concept Of T-Basis And Vector-Valued Hardy Classes, Bilal Bilalov, Sabina Rahib Sadigova

Turkish Journal of Mathematics

This paper introduces the concept of a t-basis generated by some bilinear mapping t(·;·). It is considered the vector-valued class L_p(X) := L_p(J; X), 1 ≤ p < +∞, where J = [−π, π] and X is a Banach space with the UMD property, and it is proven that the classical system of exponents {e^int}_n∈ℤ forms a t-basis for L_p(X), 1 < p < +∞. Using this fact, the Hardy vector classes _nH_p^±(X), 1 < p < +∞, different from the classical ones, are defined, and an equivalent definition of these classes is given and some of their properties are studied. In addition, the concept of t-Riesz property of a system of exponentials is introduced in L_p(X), 1 < p < +∞, and it is proved that this system has the t-Riesz property. A new method is given for establishing the Plemelj–Sokhotski formulas for X-valued Cauchy type integrals when X has the UMD property. An abstract analogue of the “1/4-Kadets” theorem is obtained for …

On The Images Of N-Ellipses Under The Möbius Transformations, Ni̇hal Özgür

Turkish Journal of Mathematics

In this paper, we examine the images of n-ellipses under the Möbius transformations (linear fractional transformations) for n ≥ 3. As a result of this investigation, we present a new and generalized version (called n-generalized Apollonius circle) of the concept of an Apollonius circle in the plane.

On Cr-Structures On The Null Tangent Bundle, Mohamed Tahar Kadaoui Abbassi, Cornelia-Livia Bejan, Khadija Boulagouaz

Turkish Journal of Mathematics

The null tangent bundle of an indefinite pseudo-Riemannian manifold is a lightlike hypersurface of the tangent bundle which inherits a CR-structure from the almost Hermitian structure defined by Oproiu on the tangent bundle. We investigate the properties of this structure in relation to the choice of the screen distribution and the geometry of the base manifold.