Niğde Ömer Halisdemir University Institutional Repository
Not a member yet
14438 research outputs found
Sort by
On the curve evolution with a new modified orthogonal Saban frame
Get PDFThe flow of a curve is said to be inextensible if the arc length in the first case and the intrinsic curvature in the second case are preserved. In this work, we investigated the inextensible flow of a curve on S2 2 according to a modified orthogonal Saban frame. Initially, we gave the definition of the modified Saban frame and then established the relations between the Frenet and the modified orthogonal Saban frames. Later, we determined the inextensible curve flow and geodesic curvature of a curve on the unit sphere using the modified orthogonal Saban frame. Also, we gave some theorems and results for special cases of the evolution of a curve on a sphere. Finally, we gave examples and their graphs for the inextensible flow equation of curvatures
Optimization of citrus fiber-enriched vegan cream cheese alternative and its influence on chemical, physical, and sensory properties
Get PDFDairy product alternatives have increased in recent years as a result of medical prescriptions or personal preferences. The main purpose of the present study was to optimize vegan-based cream cheese formulation added with citrus fiber considering the textural and physicochemical properties of the samples. The physicochemical (pH value, water activity, and color), texture, microstructure, and sensory properties of manufactured vegan-based cream cheese were characterized and compared to those of a commercial one. Three optimized products were produced, according to the textural properties. The addition of citrus fiber did not affect the pH and water activity values of the cheese samples significantly. Although citrus fiber had an effect on the color values of the samples, a significant difference in the sensory scores was not recorded by the panelists. The sample having 1.21% citrus fiber (A) showed a hardness value similar to that of control sample and it received high sensory appreciation. The sample added with 1.41% citrus fiber (B) was scored high by the panelists, with no significant difference compared to commercial cream cheese, even though it showed high hardness. According to the results of the current research, vegan-based cream cheese can be produced as a promising food as a new alternative to milk and dairy products. The present study is carried out to optimize a vegan-based cream cheese product using pea protein and citrus fiber using mixture design approach. In the first stage, physicochemical and textural characteristics of the produced cheese samples were determined and the best receipt was created based on the textural analysis and in the second stage, three different cheese samples having different citrus fiber and fat levels were prepared and compared to those of a commercial vegan cream cheese sample.imag
Investigation of the dielectric properties of acorn nest extract loaded hydrogels
Get PDFFen Bilimleri Enstitüsü, Fizik Ana Bilim DalıBu çalışmada, farklı kimyasal içeriklere sahip meşe palamudu yuvası özü yüklü hidrojeller (PYH) polimerizasyon tekniği ile hazırlanmıştır. Numunelerin karakterizasyonu, kalitatif ve morfolojik özellikleri sırasıyla X-ışını difraksiyonu (XRD) tekniği, X-ışını EDAX (EDX) ve Taramalı elektron Mikoskobu (TEM) ile yapıldı. Numunelerin elektriksel ve dielektrik özellikleri empedans spektroskopisi ile oda sıcaklığında ve 102 rad/s ila 107 rad/s frekans aralığında ölçüldü. Tüm numunelerin dielektrik özellikleri frekansa göre incelenmiş ve fiziksel nedenleri detaylı olarak tartışılmıştır. Arayüz etkileşimleri ve dipolar polarizasyon mekanizması tüm numuneler düşük frekans bölgesinde etkili olurken, elektrot polarizasyonu yüksek frekans bölgesinde dielektrik ve iletkenlik özellikleri üzerinde etkili olmuştur. Meşe palamudu yuvası özü yüklü hidrojeller için Smith abağına uyarlanmış Cole-Cole eğrileri ve eşdeğer empedans devreleri, dielektrik düzlem grafikleriyle ayrıntılı olarak gösterilmiştir.In this study, acorn nest extract-loaded (ANH) hydrogels with different chemical contents were prepared by polymerization technique. Characterization, qualitative and morphological properties of the samples were performed by x-ray diffraction (XRD) technique, x-ray (EDX) EDAX and Scanning electron Microscope (SEM), respectively. Electrical and dielectric properties of the samples were measured by impedance spectroscopy at room temperature and in the frequency range of 102 rad/s to 107 rad/s. The dielectric properties for all samples were examined according to frequency and their physical causes were discussed in detail. Interface interactions and dipolar polarization mechanism for all samples were effective in the high frequency region, while electrode polarization was effective on dielectric and conductivity properties in the low frequency region. Cole-Cole plots and equivalent impedance circuits adapted to Smith chart for acorn cupule extract loaded hydrogels were shown with dielectric plane plots in detail
The Effect of Combining Blood Flow Restriction with the Nordic Hamstring Exercise on Hamstring Strength: Randomized Controlled Trial
Get PDF(1) Background: It is a matter of curiosity what effect the blood flow restriction (BFR) method, which is usually combined with low-intensity resistance exercises, will have when used with high-intensity eccentric exercises. (2) Methods: The present study examined the effects of combining BFR with nordic hamstring exercises (NHEs) on hamstring muscle strength, bilateral deficit (BLD), and training volume. Thirty young female volleyball players, who trained three times a week, participated voluntarily in the study. These players were stratified into three groups, each comprising ten individuals: a control group (CG), an NHE group, and an NHE + BFR group. Hamstring muscle strength and BLD values were determined using an H-BORD device, while training volume was measured in terms of sets and repetitions. (3) Results: Statistical analysis revealed that there were no statistically significant differences in non-dominant and dominant leg peak torque parameters in the exercise groups (F = 2.65; p = 0.097; eta p2 = 0.17; F = 1.15; p = 0.0334; eta p2 = 0.084), while the total training volume was lower in the NHE + BFR group. (4) Conclusions: As a result, it was seen that adding the BFR method to NHE did not provide additional gains. However, due to the low training volume of BFR + NHE, it may be recommended to apply BFR together with NHE to athlete groups.Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia [PNURSP2024R 286]We would like to sincerely express our appreciation to Princess Nourah bint Abdulrahman University Researchers Supporting Project number (PNURSP2024R 286), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia for supporting this project. We thank all the volunteers and participants involved in the present study
Evaluation of Jaw Bone Change in Children and Adolescents with Rheumatic Heart Disease by Fractal Analysis
Get PDFBackground: Recognizing the oral needs of people living with rheumatic heart disease (RHD), particularly in relation to their jaws, is of paramount importance. Aims: This study aimed to evaluate potential jaw bone changes in children and adolescents diagnosed with RHD and compare them with a group of healthy children and adolescents. Methods and Material: The dental panoramic radiographs (DPRs) of 32 children and adolescents diagnosed with RHD comprised the case group. In contrast, the control group consisted of DPRs from 32 children and adolescents without any known diseases. Two regions of interest (ROI1 and ROI2) of trabecular bone and a separate region of interest (ROI3) of cortical bone were selected for fractal analysis. The mandibular cortical index (MCI) was evaluated. Results: The ROI1 fractal dimension (FD) value of the individuals in the case group was statistically higher in the right jaw than in the left jaw (P 0.05). Conclusions: The results of this study showed that bone metabolism was affected unilaterally in the condyle region and bilaterally in the gonial region of patients with RHD. It also revealed that the cortical layer was not affected
Influence of stacking order and sulfurization parameters on properties of CZTS thin films grown on flexible molybdenum substrates
Get PDFFen Bilimleri Enstitüsü, Fizik Ana Bilim DalıBu tez çalışmasında, esnek molibden (Mo) folyo üzerine manyetik saçtırma yöntemi kullanılarak Mo-folyo/CuSn/Cu/ZnS, Mo-folyo/CuSn/ZnS/Cu ve Mofolyo/ZnS/CuSn/Cu öncül katman dizilimleri üretilmiş ve devamında kesterit CZTS fazını elde etmek için Hızlı Tavlama Yöntemi (RTP) kullanılarak bu öncül katmanlar sülfür ortamında tavlanarak sırasıyla CZTS-I, CZTS-II ve CZTS-III filmler üretildi. (112) tercihli yönelimli XRD pikin FWHM değerleri kullanılarak hesaplanan kristal boyutları ve mikro-gerilmeler, CZTS-III örneğinin daha gelişmiş kristal kaliteye sahip olduğunu göstermiştir. Raman spektroskopisi ölçümleriyle tüm örneklerde kesterit CZTS fazının oluştuğu ve düşük miktarda CTS fazının varlığı doğrulanmıştır. Mofolyo/ZnS/CuSn/Cu katman sıralamasına ve CZTS-III filmlerinin SEM görüntülerinde, daha belirgin, homojen ve kompakt bir yüzey morfolojisi gözlemlenmiştir. CZTS ince film örneklerin optik bant aralık değerleri 1.44–1.50 eV aralığında değişkenlik göstermiştir. Alınan fotolüminesans (PL) ölçümleri, banttan banda geçişlerden ziyade, iletim bandından özden kusur seviyelerine geçişlerin olduğunu ortaya koymuştur.In this thesis study, Mo-foil/CuSn/Cu/ZnS, Mo-foil/CuSn/ZnS/Cu, and Mofoil/ZnS/CuSn/Cu precursor layer sequences were produced using the magnetic sputtering method on flexible molybdenum (Mo) foil followed by sulfurization process using the Rapid Thermal Annealing (RTP) method to obtain the kesterite CZTS phase, resulting in the production of CZTS-I, CZTS-II, and CZTS-III films respectively. The crystallite sizes and microstrains calculated using the (112)-preferred orientation XRD peak Full Width at Half Maximum (FWHM) values showed that the CZTS-III sample had a more promising crystalline quality. Raman spectroscopy measurements confirmed the formation of the kesterite CZTS phase in all samples and the presence of a small amount of CTS phase. In SEM images of the of Mo-foil/ZnS/CuSn/Cu layer sequence and CZTS-III films, a more distinct, homogeneous, and compact surface morphology was observed. The optical bandgap values of the CZTS thin film samples varied in the range of 1.44–1.50 eV. Photoluminescence (PL) measurements revealed transitions from the conduction band to defect levels rather than band-to-band transitions. Electrical measurements indicated that CZTS-II and CZTS-III films had lower resistivity and higher carrier concentration due to their better crystalline quality
Design and optimization of functionally graded anode electrode with integrated functional layer for microtubular solid oxide fuel cells
Get PDFThis study investigates the influence of porosity-graded anode microstructures on the performance of microtubular solid oxide fuel cells (SOFCs). Fabricated using tape casting coupled with isostatic pressing, the anode microtubes consist of three layers with varying porosities. The porosity of each layer is regulated by the quantity of pore former added to the corresponding tape casting slurry. Homogeneous microtubular anode supports having different porosities are also fabricated similarly for comparison purposes. Microtubular cells are manufactured on both types of anodes by dip coating other cell layers, and test and characterization studies are carried out. Experimental results reveal that increasing the pore former content in the anode tape casting slurry leads to reduced triple phase boundary (TPB) density, primarily due to increased porosity and pore size, resulting in higher charge transfer resistance and decreased cell performance, despite an associated decrease in the gas transport resistance. However, optimization of the anode microstructure demonstrates that porosity gradients can enhance gas transport and overall cell performance. Additionally, the study explores the impact of anode thickness and the presence of transition layers on cell performance and structural integrity.The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence work reported in this paper
The effect of hallux valgus on the anatomy of the nerves around the first metatarsal bone
Get PDFObjective To identify the variations in the location of the nerves that may be at risk in hallux valgus (HV) surgery, and to reveal whether these nerves are affected by the anatomical changes associated with HV. Method In the formalin fixed, 46 lower extremities (19 female, 27 male) (9 normal, 14 mild HV, 21 moderate/severe HV), extensor hallucis longus tendon (EHL), deep plantar artery, medial dorsal cutaneous (MDCN), deep fibular (DFN), common plantar digital (CPDN) and proper plantar digital (PPDN) nerves were examined. The branches of MDCN extending to the medial side of foot were recorded in three segments. The positional topography of nerves according to EHL were analyzed on 360(degrees) circle and clock models. Results Sex-related differences observed in some parameters in direct measurements were not found in the clock model comparisons. In advanced HV angles (> 20(degrees)), DFN was closer to EHL in the distal part of the metatarsal bone, while there was no difference in the proximal. The intersection of the medial branch of the MDCN with the EHL was more proximal in HV cases than in normal feet. The location of the nerves in the clock pattern did not change in HV. Of the nerve branches reaching the medial side of the foot, 65.2% were in Part I, 71.7% in Part II, and 4.3% in Part III. Conclusion Sex differences in the distance of the nerves to the EHL disappeared when the size effect of the cross-section of the first metatarsal bone region was eliminated with the clock model. Only in advanced HVA (>20(degrees)) (not in mild HV), the DFN being closer to the EHL distally and the intersection of the medial branch of the MDCN with the EHL in HV being more proximal than in normal can be interpreted as specific reflections of HV progress. The variations we revealed in the number of branches reaching the inside of the foot may explain the diversity of neuromas or nerve injuries associated with HV surgery.Mersin University Scientific Research Projects UnitThe authors sincerely thank those who donated their bodies to science so that anatomical research could be performed. The results of such studies can contribute to the improvement of the health service that humanity receives. For this reason, we would like to express our gratitude to these donors and their families on behalf of researchers and humanity. Also, thanks to Mersin University Scientific Research Projects Unit for supporting this study
An Investigation on CdSeTe/CdTe Stacks Deposited by Evaporation: Impact of Halide Treatment Depending on the Applied Surface
Get PDFAmong the methods applied to modify the characteristics of CdSeTe/CdTe stacks, one of the most well-known and widely used procedures is the CdCl2 halide treatment. In this connection, the influence of CdCl2 on microstructural properties, phase distribution, and optical properties of CdSeTe/CdTe stack depending on location of the employed surface is investigated. In CdSeTe/CdTe stacks deposited by evaporation in vacuum, CdCl2 halide treatment is applied to the interface of CdSeTe and CdTe, the upper surface of CdTe, and both surface regions of the stack. CdCl2 treatment applied depending on the region has a definite effect on the phase structure, interlayer CdSexTe1-x alloying rate, and crystallization quality of the stack structure. Regardless of the applied region, all CdCl2-treated stacks exhibit a granular and compact surface morphology. On the other hand, CdCl2 treated only on single surface results in a shift of the absorption edge to the shorter wavelength, but rather to the long spectral region for both surfaces. The photoluminescence spectra reveal the presence of band emissions of the CdTe layer and CdSeTe alloys. Overall, the findings of the study indicate that only the upper-surface application of CdCl2 has more promising features for potential solar cell applications
Investigation of the effects of 8-week plyometric training applied to 8-10 year old swimmers on underwater torpedo turns and some physical and physiological parameters
Get PDFSağlık Bilimleri Enstitüsü, Hareket ve Antrenman Bilimleri Ana Bilim Dalı, Hareket ve Antrenman Bilim DalıBu çalışmanın amacı, 10-12 yaş yüzücülere uygulanan 8 haftalık pliometrik antrenmanların su altı torpido dönüşlerine ve bazı fiziksel ve fizyolojik parametrelere etkisinin incelenmesidir. Yüzme yarışlarının tamamında dönüş fazlarının büyük önem taşıdığı ve yüzme performansını etkileyen önemli parametrelerden biri olduğu düşünülmekle beraber yarış performansını etkilediği de bilinmektedir. Literatür taraması yapıldığında yüzme sporcularında pliometrik antrenmanlarının yarışma performanslarına etkisini inceleyen akademik çalışmalarının az olması ve litaratüre bu alanda katkı sağlamak amacı ile bu çalışmayı araştırma gereği duyulmuştur. Yüzme branşında sporcular başarıya saniyelerle ulaştığı için, yarışmalarda torpido dönüşlerin önemi çok fazladır.Pliometrik çalışmalar, patlayıcı kuvveti en çok geliştiren antrenman metodlarından biri olduğundan bu alanda çalışmaların olmaması ve pliometrik antrenmanlarının yüzücüler üzerine etkisini incelemek ayrıca litaratüre bu alanda katkıda bulunmak amacı ile bu çalışmanın yapılması gereği duyulmuştur. Anahtar Sözcükler: Pliometrik , Antrenman,Pliometrik Antrenman , SporThe aim of this study is to examine the effects of 8-week plyometric training applied to 10-12 year old swimmers on underwater torpedo turns and some physical and physiological parameters. Although it is thought that the return phases are of great importance in all swimming races and are one of the important parameters affecting swimming performance, it is also known that they affect race performance. When the literature was scanned, there were few academic studies examining the effects of plyometric training on competition performance in swimming athletes, and it was felt necessary to research this study in order to contribute to the literature in this field. Since athletes in the swimming branch achieve success in seconds, torpedo turns are very important in competitions. Since plyometric exercises are one of the training methods that most improve explosive strength, there are no studies in this field and it is necessary to conduct this study in order to examine the effect of plyometric exercises on swimmers and to contribute to the literature in this field. has been heard. Key Words: Plyometrics, Training, Plyometric Training, Sport