Karamanoğlu Mehmetbey University
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A hemicyanine-based dual-responsive fluorescent sensor for the detection of lithium and cyanide ions: application in living cells
No full textA hemicyanine-based colorimetric and fluorometric sensor, 2-(2-(2,3,5,6,8,9-hexahydrobenzo[b][1,4,7,10]tetraoxacyclododecin-12-yl)vinyl)-3,3-dimethyl-1-propyl-3H-indol-1-ium iodide (MH-5), was developed and synthesized to detect Li+ and CN− ions in DMSO-PBS buffer solution (10 mM, pH 7.25, v/v 1:9). MH-5 displayed a rapid and highly selective colorimetric response to both Li+ and CN−, indicated by a distinct color change from pink to pale pink in the presence of Li+ and to colorless upon CN− detection, without interference from other cations or anions. The interaction mechanisms of MH-5 with Li+ and CN− ions were investigated using various analytical techniques, including 1H NMR, ESI–MS, FT-IR spectroscopy, and Job’s plot analysis. These studies suggest that CN− is detected through nucleophilic addition to the indolium moiety of MH-5, while Li+ detection occurs via coordination with oxygen atoms in the crown ether structure. The fluorescence-based detection limits for Li+ and CN− were determined to be 0.150 µM and 0.154 µM, respectively. Additionally, MH-5 was evaluated in living cells, demonstrating effective cell penetration and reliable detection of Li+ and CN− ions for potential bio-imaging applications. © The Author(s) 2025
İnsight into the photoluminescence of ba2cd(bo3)2: re3+ (re = dy, tb) phosphors
No full textDy3+ and Tb3+ ions doped Ba2Cd(BO3)2 phosphors with varying concentrations (2, 3, 4, 5, 6 mol%) were produced via the solid-state synthesis method in air. The as-synthesized phosphors were characterized. The photoluminescence (PL) and photoluminescence excitation (PLE) spectra of Ba2Cd(BO3)2 phosphors doped with 2, 3, 4, 5, and 6 mol% Dy3+ ions reveal four distinct emission bands in the blue, yellow, and red regions, with the 575 nm emission band (4F9/2 -> 6H13/2, electric dipole transition) exhibiting a notably higher intensity than the 481 nm band (4F9/2 -> 6H15/2, magnetic dipole transition). The optimal Dy3+ doping concentration was identified as 5 mol%, beyond which concentration quenching effects became apparent. Additionally, excitation and emission spectra of Ba2Cd(BO3)2 phosphors doped with 2, 3, 4, 5, and 6 mol% Tb3+ ions demonstrate efficient energy absorption at approximately 225 nm, with characteristic emission bands observed at 415, 436, 488, 544, 586, and 621 nm, corresponding to the 5D3 -> 7F5, 5D3 -> 7F4, 5D4 -> 7F6, 5D4 -> 7F5, 5D4 -> 7F4, and 5D4 -> 7F3 transitions, respectively. The ideal concentrations for Dy3+ (5 mol%) and Tb3+ (6 mol%) in Ba2Cd(BO3)2 are identified at x = 0.3717, y = 0.4064, and x = 0.2902, y = 0.5344, respectively, as per the Commission Internationale de l'Eclairage (CIE) color spectrum, positioning Dy3+-doped phosphors within the yellow spectrum and Tb3+-doped phosphors within the green spectrum. These phosphors exhibit vibrant yellow and green luminescence, demonstrating their suitability as candidates for applications in these hues. They can be employed when stimulated by near-UV, UV, and blue laser diodes for WLEDs
Drilling of carbon fiber reinforced polymer without support and using support plates with different properties
No full textDelamination damage is one of the main problems that occur when mechanically drilling laminated composite structures. Various techniques have been used to lessen the damage caused by delamination. Utilizing a backup while drilling is one such technique. However, the impact of backup with various characteristics on the composite drilling process and related delamination has not been extensively studied. Thus, the study used experimental methods to investigate the drilling of carbon fiber-reinforced polymer (CFRP) material without support and with various types of support plates (wood, plastic, and aluminum). Five distinct feed rates and two spindle speeds were used in the tests, and the thrust force damage inside the hole and delamination at the hole exit were examined. The material of the chosen backup had a minimal effect on the thrust force magnitude. Using a support plate helped to decrease the cutting force within the parameters of the study. In every test configuration, the absence of a support plate resulted in the greatest damage and uncut fibers at the hole exits. A significant amount of borehole damage was observed after the composites were machined without the support plate
Metal catalyst-free ?-amination of branched rac-C8N-type such as C7N carbasugars via intramolecular aza-michael addition: Biological evolution, DFT studies and ADME properties
No full textIn this study, a new stereospecific strategy for the preparation of C8N aminocyclohexenols such as C7N, validamine analogs were developed from starting compound 4 via intramolecular aza-michael ?-amination reaction between ?, ?-unsaturated ketones and ammonia in methanol. The strategy was to produce C8N derivatives such as validamine C7N via Kornblum-DeLaMare rearrangement, which involves stereocontrolled amination of a double bond, esterification, carbonyl group reduction, benzofuran ring opening, ammonolysis of acetate groups. The mechanism of target molecules is discussed. Pseudosugars with different configurations containing an amino group at the anomeric position were tested against ?-glucosidase, ?-glucosidase, and ?-amylase. Among these compounds, compound 12 against ?-glucosidase, compound 14 against ?-glucosidase, and compound 21 against ?-amylase exhibited the best activity compared to acarbose. Moreover, enzyme kinetic studies to understand the enzyme inhibition mechanism and DFT studies to investigate binding interactions with enzyme active sites were performed on these compounds (12, 14, and 21). Additionally, the pharmacokinetic parameters (ADME) were examined using the QikProp module to determine their potential as drug candidates. © 2024 Elsevier LtdSakarya Üniversitesi; Scientific and Technological Research Application and Research Center Sinop University; Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAK, (217Z043, 115Z446); Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTA
Novel smart materials with high curie temperatures: Eu1.90Dy0.10Ge2O7, Eu1.90La0.10Ge2O7 and Eu1.90Ho0.10Ge2O7
No full textThe Eu1.90Dy0.10Ge2O7, Eu1.90La0.10Ge2O7 and Eu1.90Ho0.10Ge2O7 powder were obtained through a solid-state reaction method via multistep firing of stoichiometric ratios of Eu2O3, GeO2, Dy2O3, La2O3 and Ho2O3 in open atmosphere at temperatures from 800 to 1150 °C. The thermal behaviour, phase formation, SEM/EDX analysis, photoluminescence properties, Curie tempereture, dielectric and piezoelectric properties of the samples were investigated by TG/DTA, XRD, SEM, PL, TG/DTA, LCR-meter and d33-meter, respectively. The germenates having triclinic crystal system have 5D0→7F4, 5D0→7F3, 5D0→7F2, 5D0→7F1 transitions of Eu3+ ions. Also, the photoluminescent germenates show electrical properties and the piezoelectric charge constant of germenates showed Eu1.90Dy0.10Ge2O7> Eu1.90Ho0.10Ge2O7 > Eu1.90La0.10Ge2O7 trend. The Curie temperature of Eu1.90Dy0.10Ge2O7, Eu1.90La0.10Ge2O7 and Eu1.90Ho0.10Ge2O7 are 825, 844 and 838 °C, respectively. Compared to commonly used piezoelectric materials, Eu1.90Dy0.10Ge2O7, Eu1.90La0.10Ge2O7 and Eu1.90Ho0.10Ge2O7 materials with very high Curie temperatures were obtained with photoluminescent properties. © 2024 Elsevier Lt
Evaluation of Maxillary Sinus Pathologies and the Posterior Superior Alveolar Artery Canal Using Cone-Beam Computed Tomography
Get PDFObjective: This study aims to determine the anatomical relationship between the posterior superior alveolar artery (PSAA) and the lateral wall of the maxillary sinus during preoperative radiological evaluations in the posterior maxillary dental region, as well as to evaluate the prevalence of PSAA and its potential associations with sinus pathologies.
Materials and methods: This retrospective study is based on the analysis of Cone-Beam Computed Tomography (CBCT) data from 510 sinuses of 255 patients. The visibility of the PSAA vascular canal, artery diameters, vertical distance between the alveolar crest and the artery, and the distance to the sinus floor were measured in coronal sections. Additionally, the relationships between sinus pathologies and septa within the sinuses and the PSAA were evaluated.
Results: PSAA was detected bilaterally in the majority of patients (70.2%). Sinus pathologies and the presence of septa were also examined, revealing that 36.9% of the sinus pathologies were bilateral. Chi-square analyses showed no statistically significant relationship between gender and the presence of PSAA. Female patients had a higher incidence of sinus pathologies compared to males (p = 0.002). No significant relationship was found between the presence of PSAA and septa.
Conclusions: This study highlights the importance of considering the anatomical position and prevalence of the PSAA during preoperative radiological evaluations in the posterior maxillary region. This study identified the PSAA as predominantly located in the lateral wall of the maxillary sinus, an anatomical feature of critical importance during preoperative radiological evaluations to minimize vascular complications.
Clinical trial number: Not applicable
Periaortic fat thickness and cardiovascular risk factors in children with congenital adrenal hyperplasia
No full textObjective: Children with congenital adrenal hyperplasia are considered to be at an elevated risk for cardiovascular morbidity and mortality. The objective of this study was to evaluate the association between periaortic fat thickness and the cardiometabolic profile in children diagnosed with congenital adrenal hyperplasia.Method: A total of 20 children and adolescents with congenital adrenal hyperplasia and 20 healthy control subjects were enrolled in the study. We investigated metabolic and anthropometric parameters, comparing these values to those of the control group. Periaortic fat thickness was assessed using an echocardiographic method that has not previously been applied to paediatric patients with congenital adrenal hyperplasia.Results: The subjects in the congenital adrenal hyperplasia group were significantly shorter than the control subjects (p = 0.021) and exhibited a higher body mass index (p = 0.044) and diastolic blood pressure (p = 0.046). No significant differences were observed between the congenital adrenal hyperplasia group and control subjects concerning age, weight, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol levels. Additionally, dyslipidemia was identified in 5% (N = 1) of the congenital adrenal hyperplasia group. The mean fasting glucose, fasting insulin, homeostasis model assessment of insulin resistance, and fasting glucose-to-fasting insulin ratio were similar between the congenital adrenal hyperplasia group and the control subjects. However, 15% (n = 3) of the congenital adrenal hyperplasia group had insulin resistance. Two children with congenital adrenal hyperplasia (10%) were diagnosed with hypertension. Periaortic fat thickness was significantly greater in the congenital adrenal hyperplasia group compared to the control group (p = 0.000), with measurements of 0.2039 +/- 0.045 mm in the congenital adrenal hyperplasia group and 0.1304 +/- 0.022 mm in the control group. In children with congenital adrenal hyperplasia, periaortic fat thickness exhibited a negative correlation with high-density lipoprotein cholesterol (r = -0.549, p = 0.034) and a positive correlation with the dose of hydrocortisone (r = 0.688, p = 0.001).Results: The subjects in the congenital adrenal hyperplasia group were significantly shorter than the control subjects (p = 0.021) and exhibited a higher body mass index (p = 0.044) and diastolic blood pressure (p = 0.046). No significant differences were observed between the congenital adrenal hyperplasia group and control subjects concerning age, weight, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol levels. Additionally, dyslipidemia was identified in 5% (N = 1) of the congenital adrenal hyperplasia group. The mean fasting glucose, fasting insulin, homeostasis model assessment of insulin resistance, and fasting glucose-to-fasting insulin ratio were similar between the congenital adrenal hyperplasia group and the control subjects. However, 15% (n = 3) of the congenital adrenal hyperplasia group had insulin resistance. Two children with congenital adrenal hyperplasia (10%) were diagnosed with hypertension. Periaortic fat thickness was significantly greater in the congenital adrenal hyperplasia group compared to the control group (p = 0.000), with measurements of 0.2039 +/- 0.045 mm in the congenital adrenal hyperplasia group and 0.1304 +/- 0.022 mm in the control group. In children with congenital adrenal hyperplasia, periaortic fat thickness exhibited a negative correlation with high-density lipoprotein cholesterol (r = -0.549, p = 0.034) and a positive correlation with the dose of hydrocortisone (r = 0.688, p = 0.001).Conclusion: Our results provide further evidence of subclinical cardiovascular disease in children with congenital adrenal hyperplasia. It is crucial to regularly assess cardiometabolic risk in children with congenital adrenal hyperplasia. The measurement of periaortic fat thickness in this population may serve as a valuable tool for identifying individuals at high risk for developing early atherosclerosis
Morphometry of latissimus dorsi in fetal cadavers for prenatal spina bifida surgery
No full textAIM: To investigate latissimus dorsi morphometry, innervation, vascularization, and variational situations in fetuses. MATERIAL and METHODS: Forty-nine fetuses, aged between 15 and 40 weeks of gestation, were examined for the morphological development of the latissimus dorsi. The horizontal lengths of the thoracolumbar fascia, the dimensions of the latissimus dorsi and its tendon were measured. Additionally, the attachments of the latissimus dorsi and the branching pattern of the thoracodorsal nerve were evaluated. The development of all measured parameters during gestational age (trimester) and their interrelationships were assessed. Data were compared across sides (right and left) and genders. RESULTS: The study found that the increase in all parameters was proportional to gestational age. No significant differences were observed between sides or genders. The latissimus dorsi was directly attached (via muscle fiber) to the iliac crest in 60.2% of cases. An 88.5% attachment rate to the inferior angle of the scapula was noted, with 4.1% of these attachments being muscular. Additionally, 9.8% of latissimus dorsi tendons were found to adhere to the teres major tendon. The thoracodorsal nerve was observed to divide into 2 to 8 branches before entering the latissimus dorsi. CONCLUSION: We believe this study will provide valuable insights into the development of intrauterine invasive fetal procedures for tendon, muscle, and nerve transfer repair and assist in determining the most appropriate timing for intervention
Defect passivation and crystallization management enabled by thulium dopant as b-site cation for highly stable and efficiency fully inorganic perovskite solar cells with over 17% efficiency
No full textDespite their outstanding thermal stability and optimal band gap for tandem devices, the development of high-performance CsPbI2Br-based inorganic perovskite solar cells is considerably hampered by defect-induced nonradiative recombination and halide ion migration. Herein, we have developed a series of CsPbI2Br inorganic perovskite materials modified by incorporation of thulium (Tm3+) ions as B-site heterovalent dopants and explored their favourable impacts on the photovoltaic and stability performance of fully inorganic perovskite solar cells (FTO/SnO2/CsPb1-xTmxI2Br/CuSCN/r-GO/Au) for the first time. The champion solar cell achieves an impressive efficiency exceeding 17 %, with less degradation (<5%) after 400 h of operational stability and ∼30 % after 320 h of shelf stability owing to suppression of nonradiative recombination of carriers and inhibition of halide ion migration by controlling crystallization and phase stabilization. Overall, Tm3+ ions do not play a role only elimination of ion migration and defects in perovskite film but also protects perovskite layer from moisture and continuous light illumination in fully inorganic perovskite solar cells. © 2025 Elsevier B.V
Functional properties of betalains: binding of hg2+ and cu2+ ions, sensor capabilities, and antimicrobial activity
Get PDFIn this study, betalain extracts were obtained from prickly pear (PPE), dragon fruit (DFE), and red beet (RBE). The total betalain content of the extracts was determined to be 335.5 mg/L for PPE, 372.38 mg/L for DFE, and 466.21 mg/L for RBE, respectively. Fluorescence titrations with metal cations revealed PPE's highest intensity at 280 nm excitation, with DFE and RBE also responding, though less so. The fluorescence intensity for all extracts decreased significantly upon adding Hg2+ and Cu2+, indicating strong binding. PPE and DFE showed higher sensitivity and affinity for these ions than RBE. Absorption at 350 nm increased notably, along with visible color changes enabling potential 'naked-eye' detection. These extracts demonstrated high selectivity for Hg2+ and Cu2+, even with competing cations. Antibacterial tests showed significant inhibition against gram-positive and gram-negative bacteria. These findings, the extracts' strong spectral responses and anti-interference properties support their use as selective, sensitive sensors for environmental monitoring and analytical applications. Due to their inherent fluorescence properties, betalains have significant potential as biosensors