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Permanent URI for this collectionhttps://ada.atilim.edu.tr/handle/123456789/18

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The Evaluation of P-Wave Parameters in Patients With Percutaneous Closure of Atrial Septal Defect
(Wiley, 2025) Astan, Ramazan; Kacmaz, Fehmi; Saricam, Ersin; Ilkay, Erdogan
Background: Atrial septal defect (ASD) can lead to volume overload and related changes in P-wave parameters in surface electrocardiograms of these patients. In this study, we aimed to evaluate the effect of volume overload on P-wave parameters in patients with ASD. Materials and methods: This study is a retrospective cohort analysis. A total of 142 patients with secundum ASD who underwent percutaneous closure were evaluated. P-wave duration (Pmax) and P-wave dispersion (PWD) were measured on the surface ECG before and 1 h after the closure procedure. We evaluated P-wave parameters in terms of defect size, duration of the volume overload, and closure device sizes. Results: Pmax and PWD were significantly decreased after the procedure compared with the values before the procedure (p < 0.001). Pmax values had a statistically significant correlation with ASD size (< 20 mm or >= 20 mm) both before and after the procedure. Pmax values were significantly higher in patients older than 30 years of age (119.6 +/- 19.5 vs. 102.7 +/- 17.1 ms, respectively; p = 0.039). A significantly positive correlation was found between pre- and post-procedural Pmax and defect sizes (r = 0.474, p = 0.019 and r = 0.4233, p = 0.04, respectively). However, no positive correlation between PWD and defect age and size was present. Conclusion: Percutaneous closure of ASD is associated with an immediate decrease in both Pd and Pmax that seems to be related to the acute volume overload cessation in cardiac chambers.
Citation - WoS: 0
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Challenges Faced by Pediatric Patients With Multiple Sclerosis During Disease Progression and Treatment: A Multicenter Cross-Sectional Study in Turkiye
(Asean Neurological Assoc, 2025) Yuksel, Didem; Yardimci, Figen
Background & Objective: Multiple sclerosis is a chronic and progressive disease characterized by inflammation, demyelination and degeneration of the central nervous system. This study aimed to describe the sociodemographic and clinical characteristics of children with multiple sclerosis. Methods: The cross-sectional study was collected data from 120 children who met the research criteria and were under follow-up at 7 hospitals in T & uuml;rkiye between August 2021 and February 2022. Ethical approval was obtained from the Medical Research Ethics Committee of Ege University. The researchers developed the "The Sociodemographic Form "used in the study by based on a comprehensive literature review and previous research experiences. The form was used according to expert opinion. Results: The study included 120 eligible patients, of whom 71.2% were girls. The mean age (+/- SD) at disease onset was 13.6 +/- 2.2 years, while the mean age at the time of the study was 15.7 +/- 1.5 years. Most of the participants were high school students (84.2%), and 53.3% resided in metropolitan areas. All participants were receiving disease-modifying therapy. The study found that 67.5% of the children had school absenteeism due to the disease. Furthermore, 75% of the children experienced supratentorial symptoms, with 50% presented with optic symptoms, and 37.5% exhibiting brainstem symptoms prior to diagnosis. Drug-related side effects were reported in 58.3% of children. Additionally,99.2% of the children received information about the disease. Furthermore, 75% of the children experienced challenges during the disease and treatment process. Among these children who encountered difficulties, 52.5% reported psychological problems, 42.5% experienced side effects due to medication, 42.5% had difficulty accessing accurate and sufficient information about disease and treatment management, 32.5% encountered social and school-related issues, and 5.8% had concerns related to the clinical environment. Conclusion: Childhood multiple sclerosis is more prevalent among girls, particularly in the relapsing-remitting form. The most commonly used treatments for pediatric multiple sclerosis include interferon beta-1a and glatiramer acetate. The findings of this study indicate that a significant proportion of participating children encountered challenges during the disease and treatment process, with more than half experiencing drug-related side effects. These challenges underscore the potential negative impact on treatment adherence in this population.
Citation - WoS: 0
Performance Improvement of Carbon Fiber-Reinforced Abs Composites by Introducing Fullerene Nanoparticles
(Wiley, 2025) Akar, Alinda Oyku; Yildiz, Umit Hakan; Tirkes, Seha; Tayfun, Umit; Hacivelioglu, Ferda
Recently, polymer composites have been extensively researched in industrial fields such as electrical conductance, ohmic heating, electromagnetic shielding and electrostatic discharge, particularly in engineering polymers reinforced with carbonaceous additions. Herein, fullerene (C60) and short carbon fiber (CF) were incorporated with acrylonitrile-butadiene-styrene copolymer (ABS) using melt-compounding followed by an injection-molding process. Composite samples were produced with contents of 20 wt% of CF besides 0.1, 0.5 and 1.0 wt% of C60. Tensile, impact, hardness and wear tests, conductive atomic force microscopy, dynamic mechanical analysis, thermogravimetric analysis, melt flow index tests and scanning electron microscopy (SEM) were performed to characterize mechanical, electrical, thermomechanical, thermal, melt-flow and structural behaviors of ABS-based composites involving CF and C60. Based on the mechanical test findings obtained for the developed composites, comprising tensile and impact test results, C60 additions contributed to a significant rise in tensile strength and impact resistance of CF-reinforced ABS composites, with a 20% increase in tensile resistance being achieved by introduction C60 into the ABS/CF structure. C60 addition enhanced efficiency by 50% in terms of tensile modulus. Electrical conductivity measurements confirmed that C60 nanoparticles and CF exhibited a synergy. The optimum synergistic ratio of C60/CF was obtained as 0.5/20. The conductive path in the ABS/CF composite system was established by incorporating C60 with different loading amounts. SEM micrographs of composites demonstrated that C60 nanoparticles were dispersed homogeneously into the ABS matrix involving lower amounts of C60. (c) 2025 The Author(s). Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Afthd: Bayesian Accelerated Failure Time Model for High-Dimensional Time-To Data
(Springernature, 2025) Kumari, Pragya; Bhattacharjee, Atanu; Vishwakarma, Gajendra K.; Tank, Fatih
Analyzing high-dimensional (HD) data with time-to-event outcomes poses a formidable challenge. The accelerated failure time (AFT) model, an alternative to the Cox proportional hazard model in survival analysis, lacks sufficient R packages for HD time-to-event data under the Bayesian paradigm. To address this gap, we develop the R package afthd. This tool facilitates advanced AFT modeling, offering Bayesian analysis for univariate and multivariable scenarios. This work includes diagnostic plots and an open-source R code for working with HD data, extending the conventional AFT model to the Bayesian framework of log-normal, Weibull, and log-logistic AFT models. The methodology is rigorously validated through simulation techniques, yielding consistent results across parametric AFT models. The application part is also performed on two different real HD liver cancer datasets, which reveals the proposed method's significance by obtaining inferences for survival estimates for the disease. Our developed package afthd is competent in working with HD time-to-event data using the conventional AFT model along with the Bayesian paradigm. Other aspects, like missing values in covariates within HD data and competing risk analysis, are also covered in this article.
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Dead Cell Discrimination With Red Emissive Carbon Quantum Dots From the Medicinal and Edible Herb Echinophora Tenuifolia
(Springer/Plenum Publishers, 2025) Ozdemir, Naciye; Tan, Gamze; Tevlek, Atakan; Arslan, Gulsin; Zengin, Gokhan; Sargin, Idris
Accurately determining the viability of cells is crucial for in vitro cell research. Fluorescence-based live/dead cell staining is a highly desirable method to assess cell viability and survival in in vitro studies. We describe a green synthesis method to create red-emissive CQDs from the medicinal and edible herb Echinophora tenuifolia using microwave irradiation. We observed that the biocompatibility and photostability of the CQDs are superior. The antioxidant capacity of the CQDs and the plant extract were also investigated using different chemical methods (DPPH, ABTS, CUPRAC, FRAP, PBD, and MCA). The antioxidant capacity of the CQDs was similar to that of the extract of E. tenuifolia. Cytotoxicity studies indicate that while the CQDs are not toxic to L929, they exhibit significant toxicity towards HepG2 cells. The CQDs exhibited a strong negative zeta potential (-44.0 mV), which contributed to their selective interaction with dead cells while being repelled by viable cells with intact membrane potentials. The optimal concentration for effective, non-toxic imaging was determined to be 25 mu g/mL, as lower concentrations did not produce detectable fluorescence. Differential staining experiments confirmed that CQDs selectively stained dead cells, with red fluorescence observed under the Texas Red filter. Moreover, CQDs exhibited favorable fluorescence intensity and stability, which may offer advantages for long-term and reliable bioimaging applications. In vitro studies on HepG2 and L929 cell lines revealed that the red-emissive CQDs from E. tenuifolia can be potentially used in bioimaging.
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Polysulfur Copolymer as a Support Material for the Preparation of a Novel Multifunctional Photocatalytic Composite Material
(Springer, 2025) Kesimal, Busra; Guner, Zuhal Vanli; Cihaner, Atilla; Kaya, Murat
One-step addition of magnetic nanoparticles and titanium dioxide nanoparticles into polysulfur copolymer as cheap and available support was reported for the first time to prepare the magnetically separable heterogeneous catalyst, PolyS-MNP-TiO2. The photocatalytic activities of the PolyS-MNP-TiO2 composite material and its constituents were examined in the methylene blue (MB) degradation, textile-based wastewater simulant, exposed to solar light. Detailed characterization of the catalysts was performed with SEM, TEM, and EDX measurements. The photocatalytic activity of the resulting composite was figured out in the removal of methylene blue dye by using a solar simulator. Significantly, the as-prepared PolyS-MNP-TiO2 exhibits exceptional photocatalytic activity and total degradation of dye molecules was achieved in 60 min. Additionally, the prepared novel photocatalyst showed enhanced stability and reusability due to the magnetic behavior of the composite material and the same portion of catalyst was used in five successive tries without apparent loss in catalytic activity by eliminating long and work-loaded processes like filtration and centrifugation.
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An Activity-Based Lessons Learned Model To Support Scheduling Decisions in Construction
(Emerald Group Publishing Ltd, 2025) Yilmaz, Anil; Akcay, Emre Caner; Dikmen, Irem; Birgonul, M. Talat
PurposeThe aim of this study is to develop an activity-based lessons-learned model that allows construction companies to capture, store, classify and reuse activity-related lessons learned (LL) from previous projects, thereby increasing the reliability of time estimates in scheduling.Design/methodology/approachScheduling is a knowledge-intensive process that requires the utilization of data and expert opinion elicitation from various levels of an organization in construction projects. This research consists of five successive steps: performing a needs analysis, proposing an activity-based lessons-learned process model, validating the proposed process model, developing a tool to apply the proposed model in a computer environment and testing the applicability of the tool. To implement the proposed model in practice, a web-based tool, namely the Construction Industry Scheduling with Activity-Based Lessons Learned Tool (ConSALL Tool), was developed. Its functionality was evaluated using black-box testing. The tool was then applied in a real construction project.FindingsResults show that ConSALL has the potential to improve scheduling decisions in construction projects by incorporating data and experience from previous projects. Findings from this research can be used to develop similar models and AI tools to foster activity-based learning in other project-based industries as well as the construction industry.Originality/valueThis paper presents an innovative approach to enhancing construction project scheduling by leveraging LL from past projects. The development and application of the ConSALL Tool demonstrate a practical implementation of the proposed model, providing a framework that can be adapted to other industries to improve project planning and execution.
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Observations on Nist Sp 800-90b Entropy Estimators (Jan, 10.1007/S12095-025-00778-7, 2025)
(Springer, 2025) Aslan, Melis; Doganaksoy, Ali; Saygi, Zulfukar; Turan, Meltem Sonmez; Sulak, Fatih
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Effect of Ti-V and Nb Addition on the Properties of Almg7cu1.2 Alloy
(Springer Int Publ Ag, 2025) Gul, Armagan; Dispinar, Derya; Aslan, Ozgur
In the development of aluminum casting alloys, considerable attention is given to the impact of various alloying elements, with numerous studies exploring how these elements influence the material's properties. However, the selection of alloying elements alone does not ensure optimal final quality. The casting process and melt treatment methods also play a critical role in achieving a defect-free structure, particularly when paired with defect characterization and final property assessment. Therefore, it is essential to investigate the interplay between alloying element choice, melt treatment, and defect evaluation in tandem. In this study, copper and magnesium main alloying elements have been chosen along with master alloys of Ti-V-Nb as grain refiners for the aluminum cast alloy. Phase formations have been investigated by simulated phase diagrams. Casting experiments have been done using a tilt pouring method into sand molds, and small bubble degassing equipment has been used to ensure the alloying and melt quality satisfying required mechanical strength. Composition and alloying have been validated by spectral analysis and XRF measurements. Microstructural analyses have been performed by both digital microscopy and scanning electron microscopy. EDS mappings have been carried out for alloying elements distributions. Internal defect distribution and defect structure have been evaluated by computed tomography (CT) scans. Both as-cast and heat-treated specimens have undergone tensile and hardness tests to characterize the mechanical behaviors. CT scans and mechanical behaviors have beencorrelated, and defect metrics have been investigated and classified according to defect surface, defect volumes and projected areas on XY-XZ-YZ planes. Contour maps of defect metrics and tensile properties have been analyzed to generate input to finite element simulations for latter stages studies, and correlation of strength-defect regressions has yielded parametric results to understand structural defects-mechanical performance relations. GTN and Beremin localization models capable of depicting material behavior in the presence of defects have been used to link the experimental and virtual validation assessments. In view of test results, a maximum of 0.125 wt% Nb content in AlMgCu-TiV alloy has been proposed having a tensile strength reaching 300 MPa-7.5% elongation at 0.75% Nb content with grain refinement effect owing to Al-Nb, Al-Ti, Al-V aluminide particles and good dispersion of Nb, Ti, V elements on the microstructure as assessed by EDS mapping. CT scan reconstruction images and metrics have successfully connected tensile strength and elongation with defect volume and defect surface area for the proposed alloy. In this context, the volume and surface area of defects have been evaluated as critical metrics in evaluating the mechanical properties of Al7MgCu1.2 cast alloys. Defect localization and failure point detection during plastic deformation zone have been demonstrated by Beremin model which can lead to future studies leveraging these metrics to validate material strength using damage models such as Gurson, GTN or Beremin for crack initiation and propagation methodologies.
Citation - WoS: 0
On the Metrizability of Suprametric Space
(Ovidius Univ Press, 2025) Karapinar, Erdal; Cvetkovic, Marija
The question of metrizability of suprametric space is answered positively. The observed metric coincides with a suprametric in a way that convergence and continuity are preserved between suprametric space and associated metric space along with the propery of a Cauchy sequence. Consequently, a suprametric space is complete if and only if associated metric space is complete. Fixed point theorems in suprametric space are obtained as a corollary of well-known fixed point results.
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Comparison of the Effectiveness of Telerehabilitation in Individuals With Osteoarthritis Following Total Knee Arthroplasty: Randomized Controlled Trial
(Elsevier, 2024) Aslan, S. N.; Gevrek, C.; Demirel, M.; Atilla, B.; Kinikli, G. I.
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Microscopic Entropy of Static Black Holes in 3d Lovelock Gravities
(Amer Physical Soc, 2025) Alkac, Goekhan; Guajardo, Luis; Ozsahin, Hikmet
We give a microscopic derivation of the semiclassical entropy of static black holes in 3D Lovelock gravities, which are certain 3D Horndeski theories that were recently discovered from higher-dimensional Lovelock gravities via various methods and admit black hole solutions analogous to higher-dimensional ones. Assuming the ground state is described by the soliton obtained from the black hole solution by performing a double Wick rotation, we reproduce the semiclassical entropy from the Cardy formula without central charges for the asymptotic growth of the number of states. We explain in detail how the mass of the soliton, which is needed in the Cardy formula, can be computed in the minisuperspace formalism.
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Marshall Plan or a Mediator: The Intellectual Structure of the Management Studies in Europe
(Inderscience Enterprises Ltd, 2025) Sozen, Hulusi Cenk; Kirkbesoglu, Erdem; Tuzlukaya, Sule; Cakar, Mehmet
This study aims at examining the role of European Management Review (EMR) within the on-going paradigmatic debates between Europe and North America concerning management and organisational research. Ten years worth of bibliometric data of the journal was gathered. Citation patterns of EMR authors were analysed according to which journals they preferred to refer to more frequently. Citation patterns of authors from sub-regions of Europe were also compared to test whether heterogeneity exists in terms of academic resource usage. The findings highlight that EMR has successfully constructed a bridge between research traditions of two continents. Qualitative, macro and theoretical articles, which are significant characteristics of the European paradigm, have a considerable rate of acceptance in EMR. Besides obeying local rules of scientific inquiry, the majority of European authors have decided to use influential North American journals. EMR has partially found a way to unify the fragmented research efforts in different parts of Europe.
Citation - WoS: 0
Unveiling the Impact of Vernalisation on Seed Oil Content and Fatty Acid Composition in Rapeseed (Brassica Napus L.) Through Simulated Shorter Winters
(Wiley, 2025) Cagli, Irem; Kivrak, Busra Elif; Altunbas, Osman; Sonmez, Cagla
Climate change is leading to warmer winters world-wide with an increasing number of extreme events every year. Studies show that winter varieties of rapeseed are particularly impacted negatively by global warming. This study investigates the molecular, physiological, and biochemical effects of diverse vernalisation scenarios (i.e., the vernalisation models) on rapeseed plants and seeds. The winter and spring varieties of rapeseed (Brassica napus L.) were subjected to short durations of vernalisation (3 and 4 weeks) as well as to 6- and 8-week long vernalisation interrupted by 1-week devernalisation intervals at warm temperatures. Our results reveal a notable difference in vernalisation responsiveness in major floral regulator FLC orthologues between the late-flowering winter variety, Darmor, the early-flowering winter variety, Bristol, and the spring variety, Helios, after 3 weeks of vernalisation. Within the three FLC genes (BnaFLCA02, BnaFLCA10, and BnaFLCC02) analysed in this study, BnaFLCA10 emerged as the most responsive to vernalisation in all three varieties. The vernalisation duration significantly influenced seed oil content and fatty acid composition in both Bristol and Helios varieties. In Bristol, the 2 + 6w vernalisation model in which vernalisation was interrupted for 1 week after 2 weeks of vernalisation and continued for another 4 weeks consistently resulted in the highest oil content and oleic acid percentage. The interrupted vernalisation (2 + 4w and 2 + 6w) also led to increased monounsaturated fatty acids across all 3 years. In Helios, non-vernalised plants produced seeds with the lowest oil content, and vernalisation duration positively correlated with both seed oil content and oleic acid percentage. Our findings unveil a robust correlation between vernalisation and seed oil content, as well as fatty acid composition in rapeseed.
Citation - WoS: 2
Citation - Scopus: 3
Antioxidant Activity of Micractinium Sp. (Chlorophyta) Extracts Against H2O2 Induced Oxidative Stress in Human Breast Adenocarcinoma Cells
(Nature Portfolio, 2024) Bulut, Onur; Kose, Iskin Engin; Sonmez, Cagla; Oktem, Huseyin Avni
In response to the growing demand for high-value bioactive compounds, microalgae cultivation has gained a significant acceleration in recent years. Among these compounds, antioxidants have emerged as essential constituents in the food, pharmaceutical, and cosmetics industries. This study focuses on Micractinium sp. ME05, a green microalgal strain previously isolated from hot springs flora in our laboratory. Micractinium sp. cells were extracted using six different solvents, and their antioxidant capacity, as well as total phenolic, flavonoid, and carotenoid contents were evaluated. The methanolic extracts demonstrated the highest antioxidant capacity, measuring 7.72 and 93.80 mu mol trolox equivalents g-1 dry weight (DW) according to the DPPH and FRAP assays, respectively. To further characterize the biochemical profile, reverse phase high-performance chromatography (RP-HPLC) was employed to quantify twelve different phenolics, including rutin, gallic acid, benzoic acid, cinnamic acid, and beta-carotene, in the microalgal extracts. Notably, the acetone extracts of Micractinium sp. grown mixotrophically contained a high amount of gallic acid (469.21 +/- 159.74 mu g g-1 DW), while 4-hydroxy benzoic acid (403.93 +/- 20.98 mu g g-1 DW) was the main phenolic compound in the methanolic extracts under heterotrophic cultivation. Moreover, extracts from Micractinium sp. exhibited remarkable cytoprotective activity by effectively inhibiting hydrogen peroxide-induced oxidative stress and cell death in human breast adenocarcinoma (MCF-7) cells. In conclusion, with its diverse biochemical composition and adaptability to different growth regimens, Micractinium sp. emerges as a robust candidate for mass cultivation in nutraceutical and food applications.
Citation - WoS: 0
An Application of Stochastic Maximum Principle for a Constrained System With Memory
(Ankara Univ, Fac Sci, 2025) Savku, Emel
In this research article, we study a stochastic control problem in a theoretical frame to solve a constrained task under memory impact. The nature of memory is modeled by Stochastic Differential Delay Equations and our state process evolves according to a jump-diffusion process with time-delay. We work on two specific types of constraints, which are described in the stochastic control problem as running gain components. We develop two theorems for corresponding deterministic and stochastic Lagrange multipliers. Furthermore, these theorems are applicable to a wide range of continuous-time stochastic optimal control problems in a diversified scientific area such as Operations Research, Biology, Computer Science, Engineering and Finance. Here, in this work, we apply our results to a financial application to investigate the optimal consumption process of a company via its wealth process with historical performance. We utilize the stochastic maximum principle, which is one of the main methods of continuous-time Stochastic Optimal Control theory. Moreover, we compute a real-valued Lagrange multiplier and clarify the relation between this value and the specified constraint.
Citation - WoS: 0
The Psychometric Properties of the Hogg Eco-Anxiety Scale in the Turkish Context
(Hogrefe Ag-hogrefe Ag Suisse, 2023) Turkarslan, Kutlu Kagan; Kozak, Ekin Doga; Yildirim, Julide Ceren
Citation - WoS: 0
The Effects of Substituting Cladribine for Fludarabine on Outcomes of a Reduced Intensity Conditioning Regimen
(Lippincott Williams & Wilkins, 2024) Sahin, Ugur; Urlu, Selin Merih; Gokmen, Ayla; Arslan, Onder; Ozcan, Muhit
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Fistulectomy and Primary Sphincteroplasty for Transsphincteric Fistula
(Coll Physicians & Surgeons Pakistan, 2025) Emral, Ahmet Cihangir; Gulen, Merter; Ege, Bahadir
Objective: To evaluate the results of patients treated with fistulectomy and primary sphincteroplasty for uncomplicated perianal fistula. Study Design: Observational study. Place and Duration of the Study: Medicana International Hospital affiliated with Atilim University, Faculty of Medicine, Ankara, Turkiye, from January 2020 to September 2023. Methodology: In this study, patients who were operated on for perianal fistula between 2020 and 2023 were retrospectively examined. Data were obtained retrospectively. All patients underwent preoperative perianal MRI. Clinical notes were evaluated with the Cleveland Clinic Incontinence Score (CCIS) by physical examination. All patients were followed up on the first postoperative day, 1st week, 1st and 3rd postoperative months. Results: A total of 44 patients who underwent fistulectomy with primary sphincteroplasty were included in the study. Twenty-six patients (59.1%) had a history of perianal abscesses. It was observed that 34 (77.3%) of the patients had posterior, 7 (15.9%) anterior, and 3 (6.8%) lateral fistulas. A total of 3 patients (6.8%) were observed to have minor worsening in their incontinence scores. There was no statistically significant difference between the preoperative and postoperative 3rd month Cleveland Clinic Incontinence Score values of the patients (CCIS mean 1.6 vs. 1.7, respectively, p >0.05). Recurrence was observed in 1 patient (2.3%) during follow-ups. Conclusion: Fistulectomy with primary sphincteroplasty is an effective and reliable method to preserve anal continence and improve quality of life.
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Analytical Modeling of Nh3 Gas Sensing Using Zigzag Graphene Nanoscrolls: Energy Band Structure and Electrical Properties
(Springer, 2025) Hosseingholipourasl, Ali
Graphene nanoscrolls (GNSs), a unique nanostructure of graphene, have garnered considerable attention due to their distinctive properties such as a rolled-up papyrus-like structure, adjustable core geometry, increased inner wall area, and enhanced surface-to-volume ratio. These properties make GNS a promising candidate for various nanoelectronic applications, including gas sensing devices. Despite its potential, GNS has been relatively underexplored in the context of gas sensing applications. In this study, we present a series of analytical models to characterize the behavior of zigzag graphene nanoscrolls (ZGNS)-based gas sensors in the presence of NH3 gas. The tight-binding technique, employing nearest neighbor approximation, is utilized to formulate the energy dispersion relation of GNS, incorporating the influence of gas molecule adsorption through parameters such as the hopping integral between GNS and gas and the on-site energy of adsorbed gas molecules. Furthermore, the derived energy equation is employed to establish the conductance relation and explore the impact of gas adsorption on the electrical conductance of GNS. Subsequently, the I-V characteristics of the GNS sensor are formulated, and the variations in current due to NH3 gas exposure are analyzed. The gate voltage is modeled as a function of NH3 concentration, and a sensing parameter is proposed based on current variations across different concentrations. Validation of the model is performed by comparing the obtained results with data extracted from previous studies. The findings demonstrate good agreement, underscoring the effectiveness of the proposed ZGNS-based sensor model for NH3 detection under varying environmental conditions.

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