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SILVER AND ZINC NANOPARTICLES BIOSYNTHESIS USING LAUREL EXTRACT AND INVESTIGATION OF THE PHOTOCATALYTIC PROPERTIES
No full textMetal nanoparticles that are widely studied in optoelectronics, catalysis, medicine, and sensors offer remarkable optical and electronic properties. To address the cost and environmental concerns associated with their synthesis, this study employs an environmentally friendly method using Laureus nobilis extract to produce silver and zinc nanoparticles, which are prominent in nanotechnology. This study includes investigations of factors such as reaction time, AgNO3/laurel ratio, Zn(Ac)2H2O/laurel ratio and temperature in nanoparticle biosynthesis to optimize the process. The next stage was set to evaluate the photocatalytic performance of these nanoparticles, specifically against the methylene blue dye under dark and UV light conditions. Parameters such as pollutant decomposition, degradation rate, catalyst stability, and nanoparticle recovery were analysed. Structural characterization of the obtained nanoparticles was performed using UV-Vis, FTIR, SEM, and XRD techniques. The photocatalytic results showed significant degradation percentages for LB-AgNP (silver nanoparticles synthesized with Laureus nobilis extract) (97.5%) and LB-ZnNP (zinc nanoparticles synthesized with Laureus nobilis extract) (90.9%). LB-ZnNP showed superior performance. Therefore, LB-AgNP and LB-ZnNP are promising photocatalysts for water purification and the elimination of toxic organic pollutants.Bartin University Scientific Research Project Coordination Unit [2018 -FEN -A-022]Acknowledgements This work was funded by the Bartin University Scientific Research Project Coordination Unit (project no: 2018 -FEN -A-022)
The application of deep eutectic solvents for protein extraction from bee bread (Perga)
No full textBee bread is one of the basic nutrients that bees use as a protein source and is formed as a result of the fermentation of bee pollen. In the last few years, this product has become increasingly recognized and consumed among bee products due to its functional properties. However, deep eutectic solvents (DES) have attracted great interest in recent years as promising green alternatives to replace traditional solvents due to their variable viscosity, low vapor pressure, application-specific adjustability, non-flammability and chemical stability. In this study, bee bread was extracted in 12 different DES with different hydrogen bond acceptor (HBA):hydrogen bond donor (HBD) combinations. The DES combination with the highest total protein content was determined to be choline chloride (ChCl)-urea. Then, ultrasonic extraction conditions were optimized for maximum bioactive extraction in extracts prepared with ChCl-urea. The optimum conditions were found as 31.3 %, 25 min, 35 degrees C for ultrasonic power, extraction time and temperature, respectively. The desirability value (d) of the model was 0.83. The extracts were analyzed for total phenolic content, total protein content, individual polyphenolics, individual amino acids and individual vitamins as well as antimicrobial and antioxidant activity tests. According to the results, total protein, total individual amino acids and total individual phenolics were higher in the extracts obtained with ChCl-urea compared to the extract prepared with conventional solvent (ethanol). In conclusion, all these findings showed that ChCl-urea combination can be an alternative to ethanol depending on the structural characteristics of the target compounds to be extracted from bee bread.Scientific and Technological Research Council of Turkiye (TUBITAK) [122O701]; TUBITAKThis study was supported by Scientific and Technological Research Council of Turkiye (TUBITAK) under the Grant Number 122O701. The authors thank to TUBITAK for their supports
The impact of inactivity during the COVID-19 pandemic on the physical performance of high school athletes
No full textBackground/Objective This study was conducted during the 2019-2020 academic year to evaluate the impact of participation in school sports on students' Body Mass Index (BMI) and Assessing Levels of Physical Activity (ALPHA) test scores. Interrupted by the COVID-19 pandemic, which led to a suspension of in-person education, the study resumed in September 2021, refocusing on the effects of pandemic-induced inactivity on the physical fitness levels of the same cohort.Methods The study included twenty-nine male high school students (age: 17,24 +/- 0,73 years), divided into thirteen athletes (participating in sports such as football, basketball, and track) and sixteen non-athletic counterparts. They underwent reassessment using the ALPHA test battery, evaluating cardiorespiratory, musculoskeletal, and motor skills fitness. Data were analyzed using independent and paired samples t-tests and a two-way repeated measures ANOVA to assess changes over time and between groups. Discriminant function analysis evaluated the ALPHA test's ability to classify students based on their athletic status pre- and post-pandemic.Results Initially, athlete students exhibited significantly better BMI, 20 m shuttle run, and 4 x 10 m speed run scores compared to their non-athlete peers. After the pandemic, only the 20 m shuttle run scores remained significantly higher for athletes, with diminished distinctions in other fitness areas. The classification accuracy of the ALPHA test battery decreased from 89.7 to 75.9% post-pandemic.Conclusion The enforced sedentary lifestyle due to the COVID-19 pandemic adversely affected all students, particularly diminishing health-related fitness parameters such as body composition, cardiorespiratory and musculoskeletal strength, and motor skills. Students previously engaged in regular physical activity, notably school athletes, experienced significant fitness declines. This highlights the urgent need for targeted interventions to encourage active lifestyles among youth in the post-pandemic phase, aiming to avert long-term adverse health outcomes
Strategic analysis of organic honey producers in Gümüşhane province
No full textLisansüstü Eğitim Enstitüsü, Organik Tarım İşletmeciliği Ana Bilim DalıYüzyıllar geçmesine rağmen insanların temel besin kaynaklarından olan bal; önemi her geçen gün daha fazla anlaşılan ürünlerin başında gelmektedir. Türkiye'de özellikle kırsal kesimde yaşayan insanların arıcılıkla uğraşları geleneksel yöntemlerden başlayarak günümüz modern üretim yöntemlerine kadar gelişim göstermiştir. Ancak arıcılık ürünlerindeki kalıntı problemleri, tüketicilerin sağlıklı beslenme talepleri, çevresel etkiler vb. durumlar son dönemde üreticileri organik yöntemlerle üretime itmiştir. Türkiye'de kirlenmemiş bakir bölgelerin başında gelen Gümüşhane; mevcut coğrafi yapısı, iklim ve bitki örtüsü ile organik bal üretimi için gerekli şartları taşımaktadır. Bölgede sanayileşmenin az olması ve tarım alanlarının sınırlılığı ise organik bal üretimini destekleyici diğer faktörlerdendir. Bölgenin sosyo ekonomik yapısına bakıldığında istihdam alanlarının yetersizliği ve sınırlı tarım arazileri organik bal üretimini bölge için stratejik bir öneme taşımaktadır. Bilindiği gibi strateji belirlenen hedeflere ulaşmak için izlenecek yollar ve yapılacak hamlelerdir. Stratejik yönetim örgüt ve ya işletmelerin sürdürülebilirliğini sağlayabilmek için stratejik düşünmeyi, analiz etmeyi ve harekete geçmeyi ifade etmektedir. SWOT analizi ise en sık kullanılan stratejik analiz yöntemlerindendir. Bu yöntemle işletmeler bünyelerinde ki güçlü ve zayıf yönlerini ayrıca piyasa ya da pazardaki fırsat ve tehditleri belirleyip kendilerine uygun stratejiler oluşturabilirler. Dolayısıyla bu çalışmada organik bal üretimi ve üreticileri literatür taraması yapılarak araştırılmış, daha sonra çalışma alanında faaliyet gösteren 26 organik bal üreticisi ile görüşmeler yapılarak Gümüşhane İli Organik Bal Üreticilerinin güçlü ve zayıf yönleri ile fırsat ve tehditleri SWOT analizi tekniği ile tespit edilmiştir. Daha sonra mevcut veriler uzman görüşüne tabi tutularak SWARA yöntemi ile bölgeye uygun arı ırkı kullanılması, bölgenin sanayileşme ve nüfüs yoğunluğunun azlığından istifade edilerek üretimin geliştirlerek arttırılması, üreticilerin toplu hareket ederek pazarlama maliyetlerini azaltmak ve yerel halka organic beslenme kültürünü yerleştirmek gibi 4 temel strateji belirlenmitir böylellikle Gümüşhane'nin ekonomik ve sosyal yapısına katkı sağlamak amaçlanmıştır. Anahtar Kelimeler: Organik bal üretimi, stratejik analiz, SWOT analizi, GümüşhaneEven though centuries have passed, honey remains one of the main food sources for people. It is a product whose importance is increasingly understood with each passing day. In Turkey, especially in rural areas, beekeeping activities have evolved from traditional methods to modern production techniques. However, issues such as residue problems in beekeeping products, consumers' demands for a healthy diet, environmental impacts, etc., have recently prompted producers to adopt organic methods. Gümüşhane, one of Turkey's unpolluted and untouched regions, meets the necessary conditions for organic honey production with its existing geographical structure, climate, and vegetation. Other factors supporting organic honey production are low industrialization in the region and limited agricultural areas. Considering the socio-economic structure of the region, the lack of employment opportunities and limited agricultural lands make organic honey production strategically crucial for the area. As is known, a strategy outlines the paths to be followed and the moves to achieve predetermined goals. Strategic management refers to strategic thinking, analysis, and action to ensure the sustainability of organizations or businesses. SWOT analysis is one of the most frequently used strategic analysis methods. With this method, businesses can identify their strengths and weaknesses, as well as market opportunities and threats, enabling them to formulate appropriate strategies for themselves. Therefore, this study researched organic honey production and producers by reviewing the literature. Subsequently, interviews were conducted with 26 organic honey producers operating in the study area. The SWOT analysis technique determined the strengths, weaknesses, opportunities, and threats of organic honey producers in Gümüşhane Province. Then, by subjecting the existing data to expert opinion, four basic strategies were determined: using bee races suitable for the region with the SWARA method, developing and increasing production by taking advantage of the industrialization and low population density of the region, reducing marketing costs through collective action of producers, and instilling an organic nutrition culture in the local people. Thus, the aim is to contribute to the economic and social structure of Gümüşhane. Keywords: Organic honey production, strategic analysis, SWOT analysis, Gümüşhane
Analytical approach to contact mechanics of functionally graded orthotropic layers with gravitational considerations
No full textContact problems involving deformable bodies are widespread in both industrial and everyday situations. They have a crucial impact on structural and mechanical systems, which has led to significant efforts in modeling and numerical simulations. These efforts aim to improve understanding and optimization in various engineering applications. This study examines the contact problem involving a functionally graded (FG) orthotropic layer resting on a rigid foundation, without considering frictional influences. A point load is applied to the layer through a rigid punch on its top surface. Additionally, the gravitational effects of the FG orthotropic layer are considered in the analyses. Material parameters and density of the FG orthotropic layer are presumed to exhibit exponential variations along the vertical axis. The resolution of the problem involves deriving stress and displacement expressions through the application of elasticity theory and integral transformation techniques. By imposing the pertinent boundary conditions onto these expressions, a singular integral equation is formulated, wherein the contact stress under the punch remains unknown. Employing the Gauss-Chebyshev integration method, this integral equation is subsequently numerically solved, particularly for a flat punch profile. The outcomes of this investigation encompass the determination of contact stresses under the punch, the critical separation load, and the critical separation point-marking the initial separation between the FG orthotropic layer and the rigid foundation. Additionally, the analysis yields dimensionless representations of normal stresses along the symmetry axis within the FG orthotropic layer, as well as shear stresses along a designated section proximate to the symmetry axis. Furthermore, it provides insights into the normal stresses along the x axis at the bottom surface of the FG orthotropic layer, contingent upon various parameters and distinct orthotropic material compositions
‘İman Etmiş Olamaz’ Kalıbıyla Nakledilen Rivâyetler Üzerine Bir İnceleme
No full textTarihî süreç içerisinde hadislerin doğru anlaşılması önemsenmiş ve bunun için hem geçmişte hem de günümüzde pek çok çalışma ve araştırma yapılmıştır. Hadisin metnine ağırlık veren bazı hadis ilimleri ve şerhler daha ziyade bu amaçla kaleme alınmış çalışmalardır. Bu araştırmada da esasen bir kısım hadislerin nasıl anlaşılması gerektiğine odaklanılmış ve içeriğinde “ ?? ???? ????? /iman etmiş olmaz” ifadesinin yer aldığı rivâyetlerin ne anlam ifade ettiği tetkik edilmiştir. Zira bu ifade, geçtiği rivâyetlerin tamamında aynı manayı taşımamaktadır. İlgili ifadenin geçtiği rivâyetin içeriğinde inanç esasları zikrediliyorsa ifade hakiki manada kullanılırken, rivâyetin içeriğinde sosyal ilişkilerden bahsediliyorsa bu durumda da mecazî anlamda kullanılmaktadır. Bir diğer ifadeyle muhtevasını inanç esaslarının oluşturduğu rivâyetlerdeki bu ifade, imanın aslının nefyine hamledilirken inanç esaslarının dışında kalan konulardan bahseden rivâyetlerde ise imanın kemaline hamledilmiştir. Bu itibarla rivâyetin muhtevası, “iman etmiş olamaz” ifadesinin anlamını belirlemektedir. Bu durum dikkate alınarak konuyla ilgili rivâyetler “imanın aslına taalluk eden rivâyetler” ve “imanın kemaline taalluk eden rivâyetler” şeklinde iki ana başlıkta incelenmiştir
Meditating role of career sustainability in the relationship between teachers’ self-efficacy and job satisfaction and subject well-being
No full textThe main purpose of this study, explore the mediating role of career sustainability in the relationships between teacher self-efficacy, job satisfaction, and subjective well-being. Teachers should have an acceptable level of satisfaction regarding self-efficacy, career sustainability, and job satisfaction to secure well-being. In a sense, this claim mandates revealing the relationships between these variables. Accordingly, we collected data from 369 Turkish language teachers aged 24–55 years employed in public schools using the Teacher Self-Efficacy Scale, Short Index of Job Satisfaction, Career Sustainability Scale, and Subjective Well-Being Scale and tested a mediation model to seek answers to our hypotheses. We collected the data using an online questionnaire battery web-based survey (Google Forms) which was created using data collection measures and demographic items. After creating the survey using Google Forms, we distributed it through various channels such as email lists, social media platforms, and professional networks (e.g., teacher WhatsApp groups, teacher Telegram groups, etc.). Respondents were invited to participate in the survey voluntarily. The findings showed that career sustainability mediated the relationships between teacher self-efficacy, job satisfaction, and subjective well-being. Accordingly, we may claim that teachers with desirable career sustainability are likely to have increased job satisfaction and well-being, contributing to their self-efficacy. This research emphasises the essential significance of career sustainability in the overall well-being and work satisfaction of teachers. Future study should investigate treatments aimed at improving career sustainability and examine these linkages in other cultural settings. © 2024 The AuthorsGoogle Forms; Akdeniz Üniversitesi, (2023/359); Akdeniz Üniversites
Ultra-thin Polarization Converter Using Single Layer Metasurface for X-, Ku-, and K-Band Applications
No full text1094In this article, an ultrathin (?0/14.9), single layer, reflective type polarization converter for either linear-to-circular (LP-to-CP) or linear-to-linear (LP-to-LP) polarization conversion is reported. It has been demonstrated to achieve the LP-to-CP conversion at two separate frequency bands, including 11.52-11.84GHz and 19.83-20.01GHz. The circular polarization type is specified as a right-hand circular polarization (RHCP) for the first band and a left-hand circular polarization (LHCP) for the second band. In both of frequency bands, the metasurface structure reveals highly efficient features. Besides that, the metasurface structure exhibits highly efficient features within 3-dB bandwidths of 10.29-12.58GHz and 19.32-20.50GHz. Crucial parameters of polarization conversion such as ellipticity, axial ratio, an
A Novel Fuzzy Cumulative Sum Control Chart with an ?-Level Cut Based on Trapezoidal Fuzzy Numbers for a Real Case Application
No full textStatistical process control (SPC) is widely used to monitor production processes in many industries under certain conditions. When dealing with a quality characteristic for uncertainty, fuzzy numbers are used in the context of the statistical process control (SPC) to monitor a fuzzy production process. The aim of this paper is fourfold. One, a fuzzy X-R control chart with an alpha-level cut is used based on trapezoidal fuzzy numbers (TFNs) for detecting the large shifts in the fuzzy process mean. Second, a fuzzy cumulative sum (FCUSUM) control with an alpha-level cut based on TFNs is firstly developed for detecting the small shifts in the fuzzy process mean. Third, the fuzzy process capability indices (FPCIs) are presented to measure the fuzzy process performance. Finally, an ultra-fine calcite production process is controlled with both the fuzzy X-R control chart and the proposed FCUSUM control chart. The results of the fuzzy X-R control charts show that the fuzzy production process is in control, and large shifts in the fuzzy process mean were detected. On the other hand, the results of the FCUSUM charts show that the fuzzy production process is out of control, and small shifts in the fuzzy process mean were detected. FPCIs are also conducted, and the results of fuzzy C-pk indices show that the ultra-fine calcite production process is not capable of meeting specification limits
Examination of some interpretive problems related to women in the context of historicity
No full textLisansüstü Eğitim Enstitüsü, Temel İslam Bilimleri Ana Bilim Dalı, Temel İslam Bilimleri Bilim DalıFelsefi bir kavram olarak tarihsellik ve tarihselcilik meselesi 16. ve 19. yüzyıllar arasındaki süreçte tarih ilminin tekrardan şekillenerek gelişme ve değişim gösterdiği bir süreç içerisinde ortaya çıkarak ilk kez Almanya'da zikredilen bir konu olmuştur. Bu, tarih ilminden ne anlaşılması gerektiği felsefî tartışmalar süreci olarak bu sürece bağlı birtakım kavramların hasıl olduğu bir dönemdir. Tarihselcilikten kastedilen şey tarihe ait olanın metodunu anlama yöntemidir. Önce batı dünyasında ortaya çıkan ve sonra Hint alt kıtalarına kadar yayılan ve nihayet İslâm dünyasına da ulaşan tarihsellik meselesi Türkiye'de henüz yeni yeni yankı bulmuştur. Müslüman tarihselcilerin kendilerine referans olarak gösterdikleri Fazlurrahman vb. düşünürler, Kur'ân-ı Kerîm'in tarihsel olduğunu söyleyerek Kur'an'ın kendi tarihi içinde anlaşılması ve yaşanan dünyanın şartlarına göre yeniden yorumlanması gerektiğini savunmuşlardır. Kadınların şahitliği, mehir hakları, çok evlilik yapamamaları, erkeklerden daha az miras almaları ve dövülmeleri gibi meseleler tarihsellik tartışmalarına konu olmuş ve günümüze göre yeniden yorumlanması gerektiği savunulmuştur. Bu çalışmada geleneksel ve modern dönem tefsirlerinin konuyla ilgili ayetlere bakışları ortaya konulmaya çalışılmış, tarihselcilerin argümanları da buna göre değerlendirilmiştir. Kur'ân-ı Kerîm, metin ve hitap şekliyle tarihsel olarak kabul edilse bile hükümleri evrenseldir ve sonsuza kadar geçerlidir.As a philosophical concept, the issue of historicity and historicism emerged in a period in which the science of history was reshaped, developed and changed in the period between the 16th and 19th centuries, and became a subject mentioned for the first time in Germany. This is a period in which a number of concepts related to this process emerged as a process of philosophical discussions about what should be understood from the science of history. What is meant by historicism is the method of understanding the method of what belongs to history. The issue of historicity, which first emerged in the Western world, then spread to the Indian subcontinent and finally reached the Islamic world, has only recently found an echo in Turkey. Fazlurrahman etc., which Muslim historicists use as their reference. Thinkers have argued that the Quran is historical and that it should be understood within its own history and reinterpreted according to the conditions of the world in which we live. Issues such as women's testimony, dowry rights, not being able to have multiple marriages, receiving less inheritance from men, and being beaten have been the subject of historicity debates and it has been argued that they should be reinterpreted according to today's times. In this study, the views of traditional and modern period commentators on the relevant verses have been tried to be revealed, and the arguments of historicists have been evaluated accordingly. Even if the Holy Quran is considered historical in its text and address, its provisions are universal and valid forever