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First-Time Identification of the PPAT Protein as a Novel Antibacterial Target: Antimicrobial and Antioxidant Insights from E. purpurea
No full textEchinacea purpurea (Asteraceae) is a perennial medicinal herb with immune-stimulating and anti-inflammatory properties. In this study, the antioxidant and antibacterial properties of the organs of the E. purpurea plant were investigated, and significant amounts of total phenolic and total flavonoid contents were detected in flower extracts. It was determined that the DPPH% values of the water extract were higher than the values of methanol extracts. It was observed that Fe3+ reduction capacity increased as the concentration increased in all plant extracts. The highest antimicrobial activity was determined to be against Pseudomonas aeruginosa (35 mm) and Klebsiella pneumonia (20 mm) at the petal (EpP)-methanol extract. In HPLC analysis of component-based phenolic substances, protocatechuic acid, caffeic acid, coumaric acid, chlorogenic acid, and ferulic acid were determined in the extracts. The lowest protein-ligand binding energy (kcal/mol) was found to be -9.6 kcal/mol in chlorogenic acid. Chlorogenic acid can bind with PPAT's T10(B)OG1, W12(b), I127(B)O, and S129(B)OG and P88(B)HN2, T10(B)N, F11(b)N, D12(B)N, S129(B)N, and K12(B)NZ amino acid residues via hydrogen bonds. The evidence collected indicates that chlorogenic acid inhibits phosphopantetheine adenylyltransferase (PPAT), validating PPAT as a potential target for antibacterial therapy for the first time. The development of selective inhibitors such as chlorogenic acid of bacterial PPAT is promising for the discovery of new antibiotics.ANKOS (Anatolian University Libraries Consortium)The authors thank ANKOS (Anatolian University Libraries Consortium) for providing financial support
Enhanced Biological, Thermal and Dielectric Properties of Polyvinyl Alcohol by a Methacrylate Polymer and Green Synthesized Silver Nanoparticles
No full textDue to the increasing adverse environmental effects of synthetic polymers, the need for environmentally friendly alternative biomaterials is increasing daily. In this context, the synthesis of novel Poly(vinyl alcohol) (PVA) -based composite materials was aimed. In this study, methacrylate-based poly(2-oxo-2-[4-(trifluoromethyl)anilino]ethyl-2-methylprop-2-enoate) (PTFMAM) polymer synthesized for the first time was blended with PVA by hydrothermal method. Biosynthesized silver nanoparticles (Ag NPs) were added to the PTFMAM-PVA blend using the hydrothermal method. Nanocomposites were characterized by XRD, SEM, TEM, and FTIR. The thermal stability of nanocomposites was determined by thermogravimetric analysis (TGA), and glass transition temperatures (Tg) were determined by differential scanning calorimetry (DSC) techniques. According to TGA data, the thermal stability of PVA was improved by blending with PTFMAM and loading with Ag NPs. While the Tg of PVA and PTFMAM-PVA were 78 degrees C and 103 degrees C, this value increased to 116 degrees C with 7% Ag NP loading. The dielectric properties of the nanocomposites also increased with the loading of Ag NPs. Ag NPs loading also decreased the solubility of PVA in water. Combining PVA with PTFMAM and Ag NP increased the oxidant/antioxidant activity. At the same time, increases in the antimicrobial activities of the nanocomposites were observed. The inhibition zones of the nanocomposites against E. coli, S. aureus, and C. albicans strains were between 8.56 and 15.08 mm. The results showed that PVA equipped with synthetic PTFMAM and biosynthesized Ag NPs caused improvements in thermal, dielectric, and biological properties. The produced PTFMAM-PVA/Ag nanocomposites showed that they could be alternative materials in areas where PVA is frequently used with their improved properties.Scientific and Technological Research Council of Turkiye (TUBITAK); Afyon Kocatepe University Scientific Research Projects Coordination Unit [24.FENED.06]Open access funding provided by the Scientific and Technological Research Council of Turkiye (TUBITAK). This study has been supported by the Afyon Kocatepe University Scientific Research Projects Coordination Unit. The Project Number is 24.FENED.06
DWDM sistemlerinde EDFA konumlandırmasının sinyal kalitesine etkisinin analizi
No full textThe positioning of Erbium-Doped Fiber Amplifiers (EDFAs) plays a crucial role in optimizing the performance of Dense Wavelength Division Multiplexing (DWDM) systems, particularly in addressing signal attenuation challenges in long-distance optical transmission. This study investigates the impact of EDFA placement configurations (booster, in-line, and pre-amplifier) on signal quality using OptiSystem software simulations. The research examines systems with 4 to 16 DWDM channels, operating at 10 Gbit/s per channel with 50 GHz spacing, varying total input power between -10 dBm to 5 dBm. Results demonstrate that the booster amplifier configuration performs best, while the pre-amplifier setup exhibits more pronounced degradation. The in-line amplifier configuration shows a balanced performance, effectively restoring signal strength while requiring less pump power than the booster configuration, making it a viable option for optimizing energy efficiency in DWDM systems. A critical performance threshold was identified between 10-12 channels, where all configurations experience significant changes in error performance.Erbiyum Katkılı Fiber Yükselteçlerin (EDFA) konumlandırılması, özellikle uzun mesafeli optik iletimde sinyal zayıflaması sorunlarının çözümünde, Yoğun Dalga Boyu Bölmeli Çoklama (DWDM) sistemlerinin performansını optimize etmede kritik bir rol oynamaktadır. Bu çalışma, OptiSystem yazılım simülasyonları kullanarak EDFA yerleşim konfigürasyonlarının (hat başı, içi ve sonu yükseltici) sinyal kalitesi üzerindeki etkisini incelemektedir. Araştırma, kanal başına 10 Gbit/s hızında ve 50 GHz aralıklı, toplam giriş gücünün -10 dBm ile 5 dBm arasında değiştiği 4 ila 16 DWDM kanallı sistemleri değerlendirmektedir. Sonuçlar, yükseltici amplifikatör konfigürasyonunun en iyi performansı sergilediğini, ön yükseltici kurulumunun ise daha belirgin bir performans düşüşü gösterdiğini ortaya koymaktadır. Hat içi yükseltici konfigürasyonu, yükseltici konfigürasyonuna göre daha az pompa gücü gerektirirken sinyal gücünü etkili bir şekilde geri kazandırarak dengeli bir performans sergilemekte ve bu da onu DWDM sistemlerinde enerji verimliliğini optimize etmek için uygun bir seçenek haline getirmektedir. Tüm konfigürasyonların hata performansında önemli değişiklikler gösterdiği 10-12 kanal arasında kritik bir performans eşiği tespit edilmiştir
Improving the Surface Finish of Spur Gears Using Palm Oil-Based Lapping: Comparison with Other Industrial Lapping Solutions
Full text linkPalm oil is among the most produced plant oils in the world and is solid at room temperature. This study aims to produce a palm oil-based lapping solution that contributes to sustainable manufacturing. A palm oil-based lapping solution was compared with grease and industrial lapping solutions. Lapping processes were conducted on cylindrical spur gear wheels following the Taguchi L27 experimental design, utilizing three distinct RPMs and varying times. The average surface roughness value after the lapping procedure diminished by 39.45% with the palm oil lapping solution, demonstrating greater effectiveness than the other treatments. The most significant percentage change among all lapping solutions was -59.06%, achieved with palm oil at 32 rpm for 10 min. On the other hand, the Taguchi L27 signal-to-noise analysis shows that the palm oil lapping solution yielded the optimal outcome at 50 rpm and 16 min. A palm oil-based lapping solution was seen as capable of replacing mineral oil-based lapping solutions.The Scientific and Technological Research Council of Turkey (TUBITAK) [125M118]This study was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) within the scope of 1002 fast-track support with project number 125M118
Separation of authority and duties in the administration of penal sanction institutions in turkey: A study from the perspective of the principle of separation of powers
No full textHukuk devletinin temel unsurlarından biri olan kuvvetler ayrılığı ilkesi, yasama, yürütme ve yargı organlarının birbirinden bağımsız ve dengeli bir şekilde çalışmasını hedefler. Bu ilke, hukuk düzeninin korunması, birey hak ve özgürlüklerinin güvence altına alınması ve kamu idaresinin şeffaflığının sağlanması açısından büyük önem taşımaktadır. Türkiye’de ceza infaz kurumlarının yönetiminde yürütme ve yargı erklerinin birer mensubu olan mülki idare amirleri ve infaz savcıları birlikte yetkilendirilmişler ve sorumlu tutulmuşlardır. Çalışmada, Türkiye’de ceza infaz kurumlarının yönetiminde mülki idare amirleri ve infaz savcılarının görev, yetki ve sorumlulukları kuvvetler ayrılığı ilkesinin ışığında incelenmektedir. Öncelikle bu ilkenin teorik temelleri ve hukuki dayanakları ele alınacak, ardından ceza infaz kurumlarının idaresindeki mevcut düzenlemeler ve uygulamalar değerlendirilecektir. Bu kapsamda, idari ve yargısal otoritelerin etkileşimi ile ortaya çıkabilecek aksaklıklar ve zorluklar analiz edilerek, ceza infaz kurumlarının yönetimini daha etkin ve sade hale getirmek adına öneriler sunulacaktır. Mevcut literatürde, ceza infaz kurumları gibi icra ettiği fonksiyon bakımından oldukça önemli ve kritik bir kurumsal yapının yönetimi ile ilgili herhangi bir çalışmaya rastlanmamış olması çalışmanın literatürde önemli bir boşluğun dolması adına ilk adımı olabileceği ihtimalini öne çıkarmaktadır.The principle of separation of powers, which is one of the fundamental elements of the rule of law, aims to ensure that legislative, executive, and judicial bodies operate independently and in balance with one another. This principle is of great importance for maintaining legal order, safeguarding individual rights and freedoms, and ensuring transparency in public administration. In Türkiye, provincial administrative officers and execution prosecutors, who are members of the executive and judicial branches respectively, have been jointly authorized and held responsible for the management of penal institutions. This study examines the duties, powers, and responsibilities of administrative governors and public prosecutors in the management of penal institutions in Türkiye within the framework of the principle of separation of powers. Firstly, the theoretical foundations and legal bases of this principle will be addressed, followed by an evaluation of existing regulations and practices in the administration of penal institutions. Within this scope, potential disruptions and challenges arising from the interaction between administrative and judicial authorities will be analyzed and offered some recommendations to simplify and enhance the efficiency of penal institution management. The absence of any studies in the current literature concerning the administration of penal institutions—despite their critical importance in terms of their functions—suggests that this study could serve as a pioneering step towards filling a significant gap in academic research
Sıçanlarda glifosat izopropilamin akut maruziyeti sonrası DNA hasarı ve oksidan/antioksidan denge değerlendirmesi
No full textIn this study, the effects of oral administration of glyphosate isopropylamine (GI) salt at different doses (1/10 and 1/2 of LD50) on DNA damage, oxidant/antioxidant balance and some biochemical parameters were investigated to evaluate the acute toxicity of glyphosate isopropylamine salt. The results showed that 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels were significantly increased, malondialdehyde (MDA) levels were increased in all tissues except blood and heart and glutathione (GSH) levels were decreased in rats in the high dose group. In addition, significant increases in catalase (CAT) and superoxide dismutase (SOD) enzyme activities were detected. Biochemical analyses demonstrated that acute exposure to herbicides led to a significant elevation in serum alkaline phosphatase (ALP), albumin and urea levels, but no significant changes in AST, ALT, GGT, total protein (Tp), creatinine and CK-MB levels. These findings suggest that exposure to high doses of glyphosate may cause toxic effects by triggering oxidative stress and DNA damage.Bu çalışmada, glifosat izopropilamin (GI) tuzunun akut toksisitesini değerlendirmek amacıyla sıçanlara farklı dozlarda (LD50’nin 1/10 ve 1/2’si) oral olarak uygulanmasının, DNA hasarı, oksidan/antioksidan denge ve bazı biyokimyasal parametreler üzerindeki etkileri incelenmiştir. Sonuçlar, yüksek doz grubundaki sıçanlarda 8-hidroksi-2’-deoksiguanozin (8-OHdG) seviyelerinin belirgin şekilde arttığını, malondialdehit (MDA) düzeylerinin kan ve kalp dışındaki tüm dokularda yükseldiğini ve glutatyon (GSH) seviyelerinin ise azaldığını göstermiştir. Ayrıca, katalaz (CAT) ve süperoksit dismutaz (SOD) enzim aktivitelerinde anlamlı artışlar tespit edilmiştir. Biyokimyasal analizler, herbisite akut maruziyetin serum alkalen fosfataz (ALP), albümin ve üre seviyelerinde artışa yol açtığını ancak AST, ALT, GGT, total protein (Tp), kreatinin ve CK-MB seviyelerinde belirgin bir değişiklik oluşturmadığını ortaya koymuştur. Bu bulgular, yüksek dozda glifosata maruziyetin oksidatif stres ve DNA hasarını tetikleyerek toksik etkilere neden olabileceğini göstermektedir
Preservice Mathematics Teachers' Mathematical Modeling Competencies: Mathematical Beliefs Perspective
No full textThis study investigated the relationship between preservice elementary mathematics teachers' beliefs about mathematics and their mathematical modeling competencies. In the study, the belief categories of the preservice teachers were first determined using Q methodology and then classified into traditional and non-traditional belief. A Mathematical Modeling Competencies Rubric was developed in line with the literature and expert opinions. Three independent experts used this rubric to evaluate holistic modeling tasks that the participants completed. The resulting scores were analyzed using the Many-Facet Rasch Model to test for differences in modeling competencies among the belief groups. The findings revealed that preservice mathematics teachers with non-traditional beliefs demonstrated higher modeling competencies than those with traditional beliefs (chi(2) = 84.7, df = 3, p < 0.001). In conclusion, the study highlights that preservice mathematics teachers' beliefs about mathematics play a crucial role in developing modeling competencies and suggests that belief structures should be considered in teacher education programs.Scientific and Technological Research Council of Trkiye (TBIdot;TAK) under the 2211 National PhD Scholarship ProgramThis research was supported by The Scientific and Technological Research Council of Turkiye (TUB & Idot;TAK) under the 2211 National PhD Scholarship Program
Classroom lighting and increasing efficiency with an energy system consisting of different types of solar panels, batteries and the grid
No full textIn the study, three objectives were achieved. The first purpose; To ensure minimum energy consumption in lighting a classroom at Afyon Kocatepe University Dazkırı Vocational School. The illumination levels of ten different points in the classroom and the outside environment were measured. The most ideal illumination level for learning in the classroom was set. For this purpose, algorithm design and implementation were carried out in order to benefit from ambient lighting as much as possible. Second purpose; It is a comparison of the energy production of Monocrystalline, Polycrystalline and Thin film solar panels at the location where the work is carried out. It is to determine the most suitable solar panel type. The final purpose: In the energy production system consisting of Monocrystalline, Polycrystalline, Thin-film solar panels, battery and grid, the best use of the produced energy is ensured by providing energy flow control. Different algorithms have been used to control the energy flow. A control card was designed to implement algorithms. With the designed control card, the current, voltage, and power produced by each of three different PV modules were measured. In addition, the current, voltage, and power used by the lighting system were also measured. PIC18F4550 microcontroller was used to provide USB connection to the computer on the control card. Thus, all data in the system is sent to the computer via a USB port. An interface was designed with C# to evaluate and instantly monitor this data. With the designed interface, all data is displayed instantly and saved to the Access database at 10-second intervals. The system can be controlled manually with the designed interface. When the records in the database were examined, 83% of energy savings were achieved with the lighting algorithm and energy flow control algorithms. With the work done, optimal lighting was provided in the classroom. In this way, many effects that would hinder education, especially visual headaches, are prevented. The effect of training is increased by increasing visual comfort
The Scale of Teacher Agency in Professional Development: The Validity and Reliability Study
Full text linkProfessional development is considered a significant component of teacher agency, recognized as a fundamental competency of the profession and a component of teacher identity. Currently, there is a notable absence of measurement tools in the extant literature that assess teachers' agency levels in the context of their professional development. Addressing this lacuna, the present study aims to develop a scale to evaluate teachers' agency levels in professional development. The study group comprised 293 teachers for exploratory factor analysis and 242 teachers for confirmatory factor analysis. The scale was developed in accordance with the recommended steps for scale development. It consists of 17 items, which are distributed across three dimensions (continuous professional development, voluntary initiatives for professional development, self-evaluation). Exploratory and confirmatory factor analyses were conducted to assess the scale's construct validity. The internal consistency of the scale was then determined using Cronbach's Alpha value. The analyses yielded the Scale of Teacher Agency in Professional Development, a scale that has been proven to be both valid and reliable in determining the level of teachers' agency in the professional development process
In vitro evaluation of bond strength between dental ceramics and titanium frameworks produced by additive and subtractive methods
Full text linkBackground This study aimed to evaluate the shear bond strength (SBS) of ceramic and titanium substructures produced by different methods. Methods After designing 51 disc-shaped samples, three groups were created according to material type and manufacturing method Cobalt-chromium (Co-Cr) group prepared by selective laser melting (GC), titanium group prepared by milling (GTi1) and titanium group prepared by selective laser melting (GTi2). Surface roughness values (Ra, Rz) of six samples from each group were examined and scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) analyses were applied to one specimen from each group, and failures were examined using a stereomicroscope. Results The mean SBS, Ra and Rz values for GC were 21.21 +/- 6.15 MPa, 5.79 +/- 0.58 mu m and 37.54 +/- 6.87 mu m; GTi1 were 25.80 +/- 7.79 MPa, 2.69 +/- 0.41 mu m and 26.05 +/- 7.60 mu m; GTi2 were 24.32 +/- 7.07 MPa, 5.91 +/- 0.51 mu m and 44.46 +/- 7.78 mu m respectively. Although the shear bond strength did not show a significant difference between the groups, the roughness values of the GTi1 group were statistically significantly lower than those of the other groups (p 0.05). Conclusions The ceramic bonding of titanium specimens produced by both methods showed values similar to those of Co-Cr and ceramic bonding used in routine treatments.Afyonkarahisar Health Sciences University Scientific Research Projects Coordination UnitWe would like to thank Afyonkarahisar Health Sciences University Scientific Research Projects Coordination Unit for their support in this research