Kastamonu University
  • Kastamonu, Turkey
Recent publications
The hypothesis of the energy adsorption phenomenon was confirmed by density distributions of CDD, TDOS, and LOL for GaN and ternary alloys of AlGaN and InGaN. Based on TDOS, the excessive growth technique on doping manganese is a potential approach to designing high‐efficiency hybrid semipolar gallium nitride–based devices in a long wavelength zone. A vaster jointed area engaged by an isosurface map for Mn doping GaN, AlGaN, and InGaN toward formation of nanocomposites of Mn@GaN–H, Mn@AlGaN–H, and Mn@InGaN–H after hydrogen adsorption due to labeling atoms of N(4), Mn(5), and H (18), respectively. Therefore, it can be considered that manganese in the functionalized Mn@GaN, Mn@AlGaN, or Mn@InGaN might have more impressive sensitivity for admitting the electrons in the status of hydrogen adsorption. Furthermore, Mn@GaN, Mn@AlGaN, or Mn@InGaN are potentially advantageous for certain high‐frequency applications requiring batteries for energy storage. The advantages of manganese over GaN, AlGaN, or InGaN include its higher electron and hole mobility, allowing manganese doping devices to operate at higher frequencies than nondoping devices. A comprehensive investigation on hydrogen grabbing by heteroclusters of Mn‐doped GaN, AlGaN, and InGaN was carried out using DFT computations. The position of the Mn‐doped energy states was evaluated via the spectra obtained from the bipolar devices with the Mn‐doped GaN/AlGaN/InGaN as an active layer.
Objectives To determine T helper (Th)1 and Th2 cytokine polarization, as well as high‐sensitive cardiac troponin I (hs‐cTnI) levels, in cats with pyometra. Methods We used 40 queens in the study. A total of 20 out of these 40 queens were diagnosed with the pyometra group (PYO) and the other 20 made up the healthy group (control; CTR). We measured concentrations of hs‐cTnI, aspartate aminotransferase (AST), creatine kinase (CK) and l‐lactate in queens from both groups. Additionally, we measured cytokine concentrations in all queens. Results The hs‐cTnI concentration in the PYO group (26.95 ± 5.08 ng/L) was significantly higher than that of the CTR group (7.00 ± 0.82 ng/L) (p < 0.000). Furthermore, the PYO group had a higher CK concentration (344.50 ± 39.63 U/L) than the CTR group (191.00 ± 15.44 U/L) (p = 0.002). The PYO group also demonstrated higher concentrations of TNF‐α (9.77 ± 0.81 ng/mL), IFN‐γ (25.37 ± 2.09 ng/mL), IL‐2 (4.37 ± 0.39 ng/mL), IL‐4 (245.64 ± 15.83 pg/mL), IL‐5 (63.13 ± 1.65 pg/mL) and IL‐10 (123.58 ± 4.30 ng/mL) compared to the CTR group (p < 0.000). Conclusions Overall, it is suggested that changes in cytokine concentrations increase in queens with pyometra, potentially causing harm to the heart muscle. It is crucial to consider that the heart muscle may also be affected in queens with pyometra during the treatment process.
Non‐structural components are difficult to recycle into fresh concrete due to their high porosity, high water absorption, and low strength. This study uses aerated concrete waste (ACW) as a case study to investigate the effect of recycled concrete aggregate on the performance of eco‐friendly foamed mortar (EFM). The results show that while incorporating ACW reduces fluidity and mechanical properties due to its porous structure, it enhances the lightweight and thermal insulation capabilities of EFM, making it suitable for non‐structural applications. When 25% ACW is applied, the 28‐day compressive strength (CS) of plain EFM decreases by 64.82%, while the hardened unit weight and thermal conductivity decrease by 17.49% and 30.85%, respectively. The addition of PPF compensates for the mechanical strength loss from ACW, with the bridging effect of PPF inhibiting crack formation and interlocking with aggregates and cement paste, though it further reduces fluidity. When 0.5% PPF is applied, the 7‐ and 28‐day flexural strength of the plain EFM increased by 77.35% and 30.54%, but this resulted in a 22.22% reduction in fluidity. This study presents a feasible approach for recycling low‐grade construction waste in EFM production, contributing to the development of sustainable construction materials.
Objectives: One-third of older adults suffer from dizziness and vertigo. Benign positional paroxysmal vertigo (BPPV), which occurs due to otoconia moving into the semicircular canal, is the most common vestibular disorder. We evaluated the connection between BPPV and geriatric symptoms. Methods: A comprehensive geriatric evaluation included daily living activities, Mini-Mental State Examination (MMSE), and Geriatric Depression Scale tests for all patients. Patients’ nutritional status was assessed using the Mini-Nutritional Assessment. Body weight and fat free mass were determined from the bioimpedance analyzer. Hand grip strength was measured using an electronic hand dynamometer to determine muscle strength. Sarcopenia was assessed using the European Working Group on Sarcopenia in Older People-2 recommendations. The patients were divided into three groups as BPPV-positive, BPPV-negative, and healthy (control). Results: Obesity, low muscle mass, dynapenia, gait speed, low gait speed, and history of falling statistically significantly differed between the three groups, but age, gender, smoking, alcohol consumption, body mass index, MMSE, depression, number of falls, and comorbid diseases did not differ. The BPPV-positive group had greater rates of obesity, low muscle mass, dynapenia, and sarcopenia than the control group (p = 0.008, 0.007, 0.01, 0.03). In the unadjusted univariate analysis, low muscle mass, sarcopenia, and obesity were risk factors for “BPPV” (Odds Ratio [OR]: 3.43, Confidence Interval [Cl]: 1.25–9.37, p = 0.016; OR: 3.47, Cl: 1.32–9.13, p = 0.011; OR: 2.71, Cl: 1.09–6.70, p = 0.031). Conclusions: Obesity, sarcopenia, and low muscle mass are risk factors for BPPV, and we urge the older population to adopt healthy diet and exercise regimens to reduce BPPV-related falls. Key Words: benign paroxysmal positional vertigo, body composition, dizziness, geriatric syndromes, sarcopenia. Level of Evidence: Level 3
This study explores the therapeutic potential of albumin-bound Zn(II)-thiosemicarbazone compounds (Alb-ZnTcA, Alb-ZnTcB) against breast cancer cells. Previous research indicates that these compounds hinder cancer cell proliferation by blocking DNA synthesis, promoting oxidative stress to induce apoptosis, and disrupting the cell cycle to inhibit cellular division. This study focuses on the loading and characterization of these potentially chemically unstable compounds on bovine serum albumin-based nanocarriers. Accordingly, unlike previous studies using albumin nanoparticles, in this study, ultraviolet light was used to precisely bind the therapeutic agent to albumin during the integration of thiosemicarbazones, achieving controlled nanoparticle size to control nanoparticle size. The mean diameter of Alb-ZnTcA nanoparticles was 32 nm, while Alb-ZnTcB exhibited an average diameter of 43 nm. Notably, Alb-ZnTcA displayed the highest cytotoxicity toward breast cancer cells, suggesting an optimal size for cellular uptake. Additionally, albumin-bound compounds showed enhanced cytotoxicity at lower concentrations, potentially minimizing adverse side effects. Apoptosis analysis indicated that both Alb-ZnTcA and Alb-ZnTcB induce cell death predominantly through apoptosis, effectively preventing the uncontrolled proliferation of cancer cells. These findings demonstrate the potential of Zn(II)-thiosemicarbazone compounds loaded on albumin-based nanocarriers for breast cancer treatment. The increased potency of Alb-ZnTcA and Alb-ZnTcB compared to free compounds, along with their ability to activate apoptotic signaling pathways in MCF-7 breast cancer cells, highlights a promising approach for future cancer therapies. This study suggests that albumin-bound Zn(II)-thiosemicarbazone compounds could offer a targeted and effective strategy in breast cancer treatment, leveraging the advantages of nanocarrier-based delivery systems.
This study aimed to investigate the macroscopic, light microscopic (LM) and scanning electron microscopic (SEM) characteristics of the pecten oculi in common kestrels (Falco tinnunculus). A total of six eyeballs from three common kestrels were used as the study material. The examination revealed that the bulbus oculi was spherical in shape and its diameter exceeded the axial-global length. In the equatorial section of the eyeball, the pecten oculi were observed to be situated on the retina layer where the optic nerve enters the eyeball, showing a posterior-to-anterior distribution. The pecten oculi appeared dark brown, with a convoluted structure, comprising approximately 15–17 vascular folds. Scanning electron microscopic examination revealed dense capillary vascular folds on the surface of the pecten oculi. Within these capillary vessels, a few hyalocytes were noted, and melanocytes were found at the edges of the folds. Light microscopic examination detected numerous large, medium and small diameter vessels within the folds of the pecten oculi, especially at the periphery of the folds and the apical parts of the pecten oculi. The findings of this study were compared with the morphological characteristics of the pecten oculi in other bird species, revealing both similarities and differences.
Rapid urban growth is a subject of worldwide interest due to environmental problems. Population growth, especially migration from rural to urban areas, leads to land use and land cover (LULCC) changes in urban centres. Therefore, LULCC and urban growth analyses are among the studies that will help decision-makers achieve better sustainable management and planning. The objective of this study was to ascertain the impact of urbanization, which resulted from migration, on the alterations in LULCC, with a particular focus on the changes in forest areas surrounding the Bartın city centre between 2000 and 2020. Spatial databases for two periods were used to determine changes in urban growth. The spatial and temporal LULCC patterns of land use were quantified by interpreting spatial data. Remote sensing (RS) and geographical information systems (GIS) have been used for data collection, analysis, and presentation. The LULCC was assessed under nine classes using optical remote sensing methods on stand-type maps created from aerial photos. To determine how urban growth affects LULCC, land use status and transition matrices were created for each of the five sprawl zones around Bartın city. The annual change in forest areas is determined by the “annual forest rate”. The results indicate that the urbanization of Bartın city from 2000 to 2020 increased by approximately 19% (2510645.82 m²). However, this did not harm the forests; cover increased by 10.32% (174729.65 m²) over the same period. The process of urbanization was particularly evident in open areas and agricultural zones. During this period, there was a 37% reduction in agricultural areas (2943229.85 m²) and a 59% reduction in open areas (1265457.76 m²). The sprawl of Bartın city can be attributed to changes in its demographic structure, which mainly includes the migration of the rural population to urban areas and the emergence of new job opportunities. Factors such as challenging urban living conditions, insecure environments because of the increase in temporary foreign asylum seekers, and retirees returning to their hometowns are believed to have contributed to this population growth.
Scientific inquiry is recognized for enhancing children’s scientific thinking, reasoning, and questioning skills at an early age, while also increasing their science capital. however, how scientific inquiry practices can be effectively implemented at this age remains a challenge. this study used an activity combining scientific inquiry and environmental education that can be used in early childhood classrooms. the details given in the study and how children were actively involved in the process were also clearly stated. in light of the questions asked by the children at the end of the activity, how scientific inquiry sprouted was discussed. This study will be a guiding light for teachers who want to employ scientific inquiry in their classrooms at an early stage and who want to use a structure integrated with the concept in the curriculum.
Heavy metal (HM) pollution in urban air, a global dilemma, has increased drastically in the last century. Aluminum (Al) is one of the HMs and a neurotoxic element that can be absorbed into human tissues through digestion, breathing, and skin. Al accumulation in humans can cause diseases and even cause death. Due to the risks it poses to human and environmental health, it is vital to track the Al contamination shifts in the airborne and decrease them. In this study, 40-year Al concentration differences in Pseudotsuga menziesii, Cedrus atlantica, Picea orientalis, Cupressus arizonica, and Pinus pinaster grown in Düzce, Türkiye, the fifth most polluted European town, in terms of direction, tree species, and tissue type were assessed. As a result, Al accumulation in the tissues generally varies as outer bark > inner bark > wood. Whole species can accumulate Al significantly, and Al transfer between adjacent cells in the wood part is limited. In conclusion, all species can be used as biomonitors to track temporal Al pollution changes. However, the highest concentrations, especially in the wood part, were observed in Cedrus atlantica, Picea orientalis, and Cupressus arizonica, and these species were chosen to be the most suitable species to be used in phytoremediation studies.
Revealing the status of forests is important for sustainable forest management. The basis of the concept lies in meeting the needs of future generations and today’s generations in the management of forests. The use of remote-sensing (RS) technologies and geographic information systems (GIS) techniques in revealing the current forest structure and in long-term planning of forest areas with multipurpose planning techniques is increasing day by day. Significant technological advances are in allowing programmers to modernize how they manage data. Sentinel-2, which is a relatively new addition to Earth observing satellites, is a new-generation satellite that has enabled classification and monitoring of land cover change with high precision at ease. Visible R, G, B, and near-infrared (NIR) bands have offered exceptional 10-m spatial reasolution, making them suitable for vegetation monitoring along with the additional 20-m bands to spare especially in chlorophyll content analyses. On the contrary, Landsat-8 and ASTER which have been longer lasting in Earth observation were rougher results especially in forestry studies. In this study, Landsat-8 and ASTER satellite images were compared against the Sentinel-2 images as a reference in conjunction with GIS techniques to monitor and assess the impact of various logging procedures, including selective logging and regeneration silviculture. The investigation employed a range of plant vegetation indices, including NDVI, GNDVI, and SAVI, to evaluate the efficacy of image resolution in detecting forest cover changes in the Kastamonu region, where the timber production is the hightest in Turkey. For selective and regeneration activities, satellite images were taken pre-harvesting and immediately post-harvesting, and index maps were produced. NDVI, GNDVI, and SAVI indices were the most accurate indicators of green vegetation change in the Sentinel-2A imagery. Similarly, for the Landsat-8 imagery, the SAVI, NDVI, and GNDVI indices were found to be satisfactory indicators. As for ASTER imagery, the success sequance was like SAVI, GNDVI, and NDVI. Based on the findings of this study, it has been noted that the ASTER imagery closeness to Sentinel-2A was more remarkable in detecting changes in green vegetation in forested areas. The data derived from ASTER imageries demonstrated superior efficacy compared to Landsat-8 in generating forest cover maps, owing to their proximity to those produced by Sentinel-2. The findings also indicated that ASTER imagery, with suitable spatial and spectral resolution, could still be utilized as efficienly as Landsats to generate forest cover density maps and monitor long-term forest conservation practices, particularly in professionally managed forests. Thus, this methodology demonstrated the capacity for efficient worldwide forest management.
Objective This study examined patients with normal hearing thresholds who had trouble understanding speech in noise. We used electrocochleography (ECochG) to detect and compare SP/AP amplitude area ratios, a potential indicator of cochlear synaptopathy, and investigate speech perception disorder in noise. Methods The study included 68 people aged between 18 and 65 years, 35 patients and 33 healthy volunteers, who applied to the otorhinolaryngology clinic between November 2023 and March 2024 with a 2‐month history of difficulty understanding speech in noisy environments. Everyone was given a tiptrode electrode ECochG test, and the results were compared between groups. An ECochG test was recorded with tiptrode electrodes and was performed on all participants, and the results were compared between groups. Results In the ECochG test, the summation potential/action potential (SP/AP) amplitude and area ratios of patients who had difficulty understanding speech in a noisy environment were statistically higher than those of the control group. Conclusion ECochG testing may provide additional evidence to evaluate auditory nerve pathways.
The conversion of agricultural biomass waste into value-added biochar (BC)-based catalysts is of great interest. Magnetic biochar is an excellent material that facilitates both solid–liquid separation and peroxymonosulfate (PMS) activation. In this study, magnetic biochar was produced from pea pod, an agricultural waste, by pyrolysis, hydrothermal methods, and precipitation. The structure, morphology, and magnetic separation properties of magnetic biochar produced from pea pod (MPPBC) were comprehensively analyzed by different characterization methods. Reactive blue 19 (RB19) was selected as a model pollutant to evaluate the performance of the MPPBC/PMS system. The effect of initial solution pH, MPPBC dosage, PMS concentration, initial RB19 concentration, reusability, and concentrations of anions and natural organic matter concentrations on the removal of RB19 in the MPPBC/PMS system was investigated. The results showed that MPPBC could effectively activate PMS, and RB19 removal reached 85% at an initial solution pH of 3, an MPPBC dosage of 0.20 g/L, a PMS concentration of 0.50 mM, an initial RB19 concentration of 25 mg/L, and an oxidation time of 60 min. The reusability of MPPBC showed an 8% decrease in the removal efficiency of RB19 after four uses. Anions and natural organic matter added to the solution were found to decrease the removal of RB19. The kinetics of RB19 removal in MPPBC/PMS system was determined using first order, second order, and Behnajady-Modirshahla-Ghanbery (BMG) models. As a result of kinetic calculations, the BMG kinetic model was found to be more effective for describing the removal efficiency of RB19.
Early diagnosis and timely initiation of effective treatment are critical for the pneumonic pasteurellosis, which is mostly caused by Mannheimia haemolytica. But recently, strains of M. haemolytica resistant to antibiotics have begun to emerge, making the treatment of infections more difficult. Therefore, it is important to investigate the erm (42), msr (E) and mph (E) genes, which are held responsible for the resistance to antibiotics.The purpose of the present study was aimed to diagnose the presence of M. haemolytica by IHC method from lung tissue samples of young and adult cattle, and calves, also to detect erm (42), msr (E) and mph (E) genes, which are mostly detected in Pasteurella multocida but recently detected in M. haemolytica, by PCR method. In present study, paraffin blocks obtained from 100 young and adult cattle, and calves lung samples, and whose treatment was not responded, were used. Accordingly, the presence of M. haemolytica was detected by IHC in a total 52 cases of in 21 (38%) of the calves, 22 (69%) of the young cattle, and 9 (69%) of the adult cattle. At least one macrolide resistance gene was found by real–time PCR method in 75% of these positive cases. It was thought that the percentage frequency of these genes, which cause resistance by increasing the minimum inhibitory concentrations of macrolide group antibiotics used in the treatment, by high amounts, makes the treatment of infections difficult and causes serious economic losses by causing errors in effective antibiotic selection. Recently, strains of M. haemolytica resistant to antibiotics have begun to emerge, making the treatment of infections more difficult. For this reason, it is recommended that this type of prevalence studies should be renewed periodically due to possible resistance development and the repeated use of antibiotics with resistive shape should be avoided.
In the dynamic nature of hospitality and tourism (H&T) research, it is increasingly difficult to distinguish highly-cited-papers (HCPs) due to the rapid proliferation of publications. This study employs machine learning techniques to identify the predictors of citation counts in H&T research over both short-term (5-year) and long-term (20-year) periods using HCPs. The analysis integrates a theoretical framework comprising normative theory and social constructivist theory. The findings indicate that international citation, PlumXmetrics, and early citations are the most effective determinants in both periods. Furthermore, while the importance of international citations is evident in both periods, the order of importance of the other two predictors changes. PlumXmetrics are more important in the long-term, while early citations are more important in the short-term. In conclusion, this comprehensive and up-to-date study of citation dynamics provides valuable insights for scholars and other stakeholders interested in enhancing the visibility and influence of H&T literature.
The search for superconductors with superior mechanical properties has driven research into homovalent replacements. In this work, we have systematically incorporated Tb/Y and Zn/Cu dopants into Y3-x(Tb)xBa5Cu8O18-δ and Y3Ba5Cu8-x(Zn)xO18-δ based bulk superconductors using the sol-gel technique. Our goal was to explore the fundamental mechanisms linking dopant concentration (0–15%), substitution, processing, and mechanical performance. Understanding these mechanisms can help in designing robust and high-performance superconducting materials for various technological applications. The samples were extensively investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), Vickers hardness measurements and related calculations. The hardness data were further evaluated using Meyer’s law, the proportional sample resistance (PSR) model, the elastic/plastic deformation (EPD) model, the Hays-Kendall (HK) approach, and the indentation-induced cracking (IIC) model. This study reveals the fundamental changes in the properties of Y-358 superconductors due to Tb/Y and Zn/Cu substitutions. The interpretation of the XRD study results leads to the conclusion that all samples have an orthorhombic crystal structure. XRD results confirmed that all samples maintained an orthorhombic crystal structure. However, significant XRD peaks indicated that Tb doping above 10% introduced impurities. Additionally, micromechanical studies demonstrated that hardness values in the plateau region consistently decreased as Tb and Zn doping ratios increased. A decrease in hardness values with increasing applied load, known as the indentation size effect (ISE), was also observed. Among the modeling techniques applied, the IIC model provided the best fit for the hardness test results.
In the active decision- making process, during the purchase, the most notable case is satisfaction ordissatisfaction of the customer is caused in the purchasing decision. In the recent years, the new structures havebeen composed under the name of “Customer Complaint Management” (CCM). In terms of emphasizing theimportance of research and in order to understand the effectiveness of CCM, researched that how the consumerswere evaluated the CCM performance of GSM companies in Turkey. The research was conducted on theprimarily-handed data. This study is a survey that aims to evaluate the “solving the consumer’s complaint for theTurkcell, Vodafone, Avea companies”. And their performances related to CCM dimensions such as transparency,accessibility, responsiveness, objectivity and consumer oriented strategies is perceived by the consumers.Frequency distribution of survey data investigated and reliability of research variables tested by Cronbach Alphaanalysis. Two discrimination functions were evaluated. With the first discrimination function, it is seen that theAvea has the highest value in comparison with the other companies (0,566); with the second discriminationfunction, it is seen that Vodafone has the highest value (0,583). Turkcell has no highest discrimination value incomparison with the other GSM companies.
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1,448 members
Bahattin AYDINLI
  • Education Faculty
Gökhan Şen
  • Forestry Economics
Talip Çeter
  • Department of Biology
Ibrahim Akar
  • Gifted Education
Seyma Sengil Akar
  • Department of Elementary Education
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Kastamonu, Turkey