Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Uzun, Sevda(64)
- Merdan, Mehmet(47)
- Baltaci, Cemalettin(35)
- Kulakaç, Nurşen(28)
- Duran, Celal(27)
- Ozdes, Duygu(24)
- Turan, Ibrahim(24)
- Demir, Selim(23)
- Türkkan, Tuğba(22)
- Bayrakdaroglu, Serdar(21)
- Topal, Fevzi(21)
- Öztürk, Serkan(21)
- Ürkek, Bayram(21)
- Gücer, Mehmet Ali(20)
- Akar, Zeynep(19)
- Kaygusuz, Abdullah(19)
- Topal, Meryem(19)
- Anaç, Halil(18)
- Aydin, Aydanur(18)
- Batan, Nevzat(18)
- Erata, Hüseyin(18)
- Tuncer, Metin(18)
- Akyürek, Suat(17)
- Baltacı, Cemalettin(17)
- Karimullah, Suud Sarim(17)
- Acet, Tuba(16)
- Akar, Bülent(16)
- Ashyralyyev, Charyyar(16)
- Düzgün, Azer Özad(16)
- Hintistan, Sevilay(16)
- Yılmaz, Coşkun(16)
- Aliyazicioglu, Yuksel(15)
- Kaya, Hacer(15)
- Kurnaz, Muammer(15)
- Kurt, Kemal(15)
- Ozden, Talat(15)
- Yilmaz, Coskun(15)
- Yuksel, Ferhat(15)
- Yücel, Cem(15)
- Öz, Mehmet(15)
Yayınlar
- MakaleAçık Erişim2025THE IMPACT OF ESG CONTROVERSIES ON THE MARKET VALUE IN THE ENERGY SECTOR
Sayilir, Ozlem; Chelery Komath, Muhammed Aslam; Karaaslan, Ibrahim
The energy sector has relatively higher exposure to scandals and controversial publicity due to the nature of industry operations. AThus, this study focuses on the energy sector to evaluate the impact of ESG (Environmental, Social and Governance) controversy scores of LSEG database on market value of firms. We investigate the relationship between ESG controversies and the market value of 393 firms using annual data from 2013 to 2022 through Dynamic Panel Data system GMM Regression Models. The findings of the study reveal that the market value of firms in the previous period has had a statistically significant positive effect on the market value of firms in the current period. Our analysis reveals a positive and statistically significant association between Governance Controversy scores and market value. Our findings suggest governance controversies have the most direct and measurable impact on firm value in the energy sector, possibly due to their stronger influence on operational performance and investor confidence. Implications of the study may help investors and policymakers to make decisions that prioritize ESG considerations in the energy sector as firms with fewer governance controversies are rewarded by investors with higher valuations.
AtıfWoS1OpenAlex2
İncele - MakaleAçık Erişim2025The Idea of Hanafism in Imam al-Rabbani and the Defense of Abu Hanifa
Karayígít, Iskender; Yilmaz, Fetullah
Imam al-Rabbani (d. 1034/1624), who came to the forefront in Islamic history mostly with his Sufi identity and was known as the sheikh of the order, although he mostly focused on Sufism, stood against the efforts to distort Islam during his lifetime and struggled in the theological and political fields. In this context, he made efforts to ensure the failure of Akbar Shah's (d. 1014/1605) project of Din-i Ilahi. In addition to his important works in the fields of sufism and theology, Imam al-Rabbani was also interested in many issues of Islamic jurisprudence (fiqh) and its history. As a person who inherited the legacy of his predecessors, he felt the need to speak on many issues related to fiqh. One of these is the criticism made about Ab & umacr; Hanifa (d. 150/767) and his school of thought. Imam al-Rabbani, especially in his work Makt & umacr;bat, was involved in the debates around the concepts of ahl al-ra'y and ahl al-hadith, and naturally tried to defend the Hanafi sect to which he belonged and its imam Ab & umacr; Hanifa with a number of evidences from different perspectives. He objected to the characterization of the Hanafi imams as mere ra'yists (lit. opinionists), stating that they accepted hadiths but also had their own methods of deriving rulings. Again, he was not contented with only some 'scientific' evidences in his discussion of Hanafism, but he also strengthened his defense with spiritual, allegorical, and mystical arguments, such as the similarity between Jesus Christ and Ab & umacr; Hanifa in ijtihad, the fact that Jesus would act in accordance with the Hanafi school of thought after his descent, and the fact that Hanafi sect possesses the perfection of prophethood. By responding to the claims of the opponents in this way, Imam al-Rabbani tried to justify the Hanafi school of thought. In this article, some of the spiritual-ischemic qualities that Imam al-Rabbani attributed to Hanaf is and his responses and defenses to the allegations put forward by some ahl al-hadith scholars will be discussed.
- MakaleAçık Erişim2025An Investigation into the Impact of Influencers Producing Technological Content on Instagram on Customers' Purchasing Decisions
Çelik, Kamil; Tas, Ahmet
Nowadays, social media influencers play a significant role in the world of marketing. Social media influencers reach large audiences by producing content on social media platforms, and they exert considerable impact on these audiences. The literature suggests that social media users form parasocial relationships, and these relationships develop based on the influencer's characteristics, such as attractiveness, expertise, credibility, and similarity. It has also been proven in various studies that social media influencers have a strong effect on increasing the purchasing intentions of their followers. In this study, the effects of social media influencers on parasocial relationships and the purchasing intentions of their followers were examined. The research was conducted among Instagram users in Turkey, and the data were collected using a survey method. The survey included statements aimed at measuring elements such as parasocial relationships, attractiveness, expertise, credibility, and similarity. Because of the data analysis, it was found that characteristics such as influencers' attractiveness and expertise strengthen parasocial relationships, and these relationships positively influence followers' purchasing intentions. Additionally, the perception of fairness also had a significant impact on these relationships. These findings suggest that social media influencers can be an effective tool in marketing strategies.
- MakaleAçık Erişim2025The interplay between university students' needs, maturity levels (personal, familial, and social), and life satisfaction
Akyüz, Ahmet Mutlu; Durmus, Ibrahim
It is essential for young Turkish individuals (university students) to rapidly develop their skills and abilities to take on leadership roles in society. To become well-equipped individuals who contribute to societal welfare and development, these young adults must undergo a healthy adolescent maturity process. Therefore, providing a supportive environment for Turkish adolescents during their maturation is crucial. This study investigates how fulfilling all hierarchical needs (PSN, LBN, ESAN) affects Turkish adolescents' life satisfaction (LS) and their personal (PM), familial (FM), and social (SM) maturity levels. The study sample consists of 397 Turkish university students. The proposed research model was tested using PLS-SEM analysis. The findings indicate that fulfilling all hierarchical needs positively affects life satisfaction. Additionally, life satisfaction serves as a mediator between the fulfillment of hierarchical needs and maturity levels. However, the most fundamental physical and security needs are not adequately met, hindering personal maturity. Furthermore, love and belonging needs and esteem and self-actualization needs positively impact all maturity levels.
- MakaleAçık Erişim2025Scopus SJRQ3SOME PHYSICOCHEMICAL, COLOR, COOKING, BIOACTIVE AND SENSORY PROPERTIES OF TURKISH NOODLES: ENRICHED WITH ARONIA POWDER (ARONIA MELANOCARPA)
Karademir, Emine; Yuksel, Ferhat; Baltaci, Cemalettin
Aronia (Aronia melanocarpa) is a fruit with a high polyphenol content, and its use is increasing due to its potential health effects with increased polyphenol content. The widespread consumption of Turkish noodles and similar products in society is important for increasing their nutritional quality. The aim of this study was to evaluate the physicochemical, color, bioactive, and sensory properties of noodle samples to which aronia powder was added at different concentrations of 2%, 4%, 6%, 8%, and 10%, respectively. Total Polyphenol Content (TPC), Total Antioxidant Capacity (TAC), and Total Flavonoid Content (TFC) amounts were found to be significantly increased (p<0.05). In addition, significant increases were found in the antioxidant activity (ABTS(center dot+), DPPH and FRAP) of the samples. According to the sensory evaluations, the noodles with 8% aronia had a high level of general acceptability, while the group with 10% aronia had a lower level. Consequently, we observed that adding aronia could yield an acceptable noodle enriched in bioactive components.
- MakaleAçık Erişim2025Scopus SJRQ4First Aid Self-efficacy in Mothers of Children Aged 0-4 Years: The Gümüşhane Example
Göger, Berrin; Kahriman, Ilknur; Çolak, Bahar
Introduction: The high relationship between the effective application of first aid after home accidents and survival determines the priorities in first aid. Childcare is mostly the responsibility of mothers, and their knowledge and practices regarding the management of home injuries are crucial in reducing morbidity and mortality associated with home accidents. This study aimed to examine the first aid self-efficacy of mothers with children aged 0-4 years to manage their children's home accidents. Methods: This cross-sectional study, focusing on the first aid self-efficacy of mothers with children aged 0-4 for home accidents, was conducted with 266 mothers at a district government hospital affiliated with the Ministry of Health in the Eastern Black Sea Region between January 1, 2023, and August 1, 2023. Data were collected through a demographic information form and the first aid self-efficacy scale for home accidents. Results: The mean score of the first aid self-efficacy scale in home accidents was found to be 2.15 +/- 0.95 and significant differences were found according to the mother's level of education, number of children, income status, caregiver of the child and mothers' first aid status. Conclusion: In conclusion, the findings of the study showed that first aid self-efficacy is not based solely on demographic factors, but instead may be shaped more by education, experience and the general approach of parents as parents, although mothers' knowledge of first aid was below average.
AtıfOpenAlex3TR Dizin2İncele - MakaleAçık Erişim2025Measuring Türkiye's Fiscal Credibility and Transparency through Fiscal Balance and Debt Stock
Ibrahim, Al; Yildiz, Gizem Akbulut; Yildiz, Baris
Fiscal credibility and fiscal transparency affect many basic macroeconomic variables, especially economic growth, inflation and interest rates through expectations. Therefore, increasing credibility and transparency increase the effectiveness of fiscal policy by enabling better management of expectations. The aim of this study is to determine T & uuml;rkiye's fiscal credibility and transparency. For this purpose, T & uuml;rkiye's fiscal credibility and transparency were measured for the 2010-2023 period with the help of various indices, based on the International Monetary Fund's fiscal balance and debt stock expectations. According to the findings, it is possible to say that fiscal credibility decreased in T & uuml;rkiye, the absolute deviation between fiscal balance expectations and official targets increased, and fiscal transparency decreased, especially in the 2019-2022 period.
- MakaleAçık Erişim2025Scopus SJRQ2Optimizing Land Image Classification: A Deep Learning Approach with ResNet-101 on the EuroSAT Dataset
Celik, Fatih; Celik, Kemal
The classification of image is essential to make LULC (Land Use Land Cover) maps. However, the classification of land cover plays a vital role for studying and modernizing the land areas. Recently, deep learning (DL) techniques have achieved outstanding performance in the classification of high-resolution images. Different techniques have been employed in traditional methods to identify LULC due to its complex and ever-changing nature. However, these studies have shown improved outcomes despite some restrictions such as inaccuracies and reduced performance. To address these problems, the proposed study introduces a Squeeze Synchronization Layer (SSL) and a Convolve Craft Focus Module (CCFM) where, SSL reduces input data complexity by removing noise and irrelevant information from images using pooling and convolutional operations also, CCFM enhances feature extraction to improve land classification accuracy. The EUROSAT land image dataset is utilized for the evaluation of the introduced model. Whereas, the dataset comprises of 64x64 images, which are captured by satellite Sentinel-2A in ResNet 101 input layer. Although, a SSL is suggested, and a CCFM is implemented in the convolutional layer for classifying land images. However, the efficiency of the system is evaluated by measuring performance metrics such as recall, F1score, precision, and accuracy values of the proposed system. The accuracy value of the proposed system is 96% of accuracy, 100% of precision, 100% of recall, and 100% of F1-score, signifies the superior efficiency of the proposed model.
AtıfWoS4OpenAlex3İncele - MakaleAçık Erişim2025As if I don't belong here. First-Year Experiences of International Nursing Students at University - A Qualitative Study
Tuncer, Gulsum Zekiye; Tuncer, Metin
Background: The rapid adaptation of international nursing students to university life enables them to actively continue their education without disruption in the following years. Identifying the challenges faced by these students, who are future nursing professionals, is essential fortheir adaptation and professional development. Aim: This study aimed to explore the perspectives of international nursing students regarding their first-year experiences at university. Methods: This study employed a descriptive qualitative research design. The Consolidated Criteria for Reporting Qualitative Research (COREQ) was used for reporting. The sample consisted of 13 international nursing students enrolled in the Faculty of Nursing at a university. Data were collected through face-to-face, individual, in-depth interviews using semi-structured interview questions. Content analysis was used to analyze the data. Results: The mean age of the nursing students was 23.3 years. Among the participants, seven were women, 11 had been residing in Turkiye for approximately one year, 12 were from Iran, and one was from Iraq. Three key themes emerged in this study: Facilitators of Adaptation, Challenges, and Coping. The students identified several facilitators of adaptation, including similarities between the Turkish economy and culture and their home countries' economies and cultures, proficiency in the Turkish language, studying at a nursing school aligned with their career goals, and receiving social support from their relatives. However, they also faced challenges such as language barriers, cultural differences, discrimination, social isolation, homesickness, and academic and clinical difficulties. Conclusion: International nursing students may encounter language barriers, cultural differences, and education-specific challenges during their first year of nursing school. In this context, developing support mechanisms to guide these students in their academic and social lives will facilitate their ability to cope with these difficulties.
AtıfWoS3OpenAlex3İncele - MakaleAçık Erişim2025Scopus SJRQ1The effect of Augmented Reality (AR) supported geometric shape learning on children’s visual perceptual development in early childhood education
Özel, Özge; Hançer, Buse; Sop, Aylin
This study examined the impact of an Augmented Reality (AR)-based virtual application on preschool children's visual perception development in geometric shape learning. A quasi-experimental research design was employed. The study sample consisted of 26 preschool children, aged 5–6, from a public school in Türkiye. The children in the experimental group engaged with AR-supported materials, allowing them to explore geometric shapes interactively and listen to their properties in a virtual environment. Each child participated individually in the learning application for 50–60 minutes. The Frostig Visual Perception Test was administered as both a pre-test and post-test. Results indicated that the AR-based learning application had a statistically significant positive effect on preschool children's visual perception development.
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İncele - MakaleAçık Erişim2025Scopus SJRQ2Investigation of the Effects of Filling Speed, Casting Temperature and Metallurgical Quality on Fluidity of Lamellar Graphite Cast Iron at Different Section Thicknesses
Köse, Sami; Çolak, Murat; Şüküroğlu, Ebru Emine
In this study, the fluidity properties of the alloy were investigated at different casting temperatures, different section thicknesses, and varying casting parameters of lamellar graphite cast iron materials. To achieve our goal, we utilized sand molds that were created with specific parameters including pouring temperature, metallurgical quality, section thickness, and fluidity test model. These molds were used for casting. Thus, the effect of fluidity properties in changing casting conditions and liquid metal advance distances at determined section thicknesses was investigated. Modeling was carried out with FlowCast casting simulation software by determining the liquid metal advance distance depending on the section thickness in the castings made in sand molds under changing casting conditions. The fluidity and advance distance of the liquid metal was determined comparatively with experimental and modeling techniques under the changing casting conditions in the parameters determined in this study. When the outcomes were examined; it was observed that different liquid metal advance distances occur at different cross-section thicknesses depending on the changing conditions.
AtıfScopus8WoS8OpenAlex7İncele - MakaleAçık Erişim2025Scopus SJRQ2Optimal Ratio of Steel and Polyester Fibers on the Mechanical Behavior of Alkali-Activated Concrete Produced by Industrial Waste Minerals
Aksüt, Yavuz Selim; Çullu, Mustafa; Yetgin, Şükrü
Alkali Activation Concretes (AAC) have many superior properties compared to Ordinary Portland Cement Concrete (OPC). However, it shows traditional concrete behavior with its brittleness. In this case, the tensile strength and flexural strength which are weak in addition to ductility is being studied to be increased by using various artificial and natural fibers. In this context, it is inevitable to conduct multifaceted research to improve the behavior of Fiber Alkali Activated Concrete (FAAC). In this study, 13 different mixes were made using steel and polyester fibers in different proportions by volume (0%; 0.25%; 0.50%; 0.75%; 1%) separately and hybrid. The mechanical properties of cubic (150 × 150 × 150 mm), cylindirical (100 × 200 mm) and prismatic (150 × 150 × 600 mm) specimens were determined including compressive strength, modulus of elasticity and poison ratio, splitting tensile strength and flexural strength (toughness-energy absorption capacity and modulus of rupture). crack formation in concrete occurs early and a significant decrease in strength is observed due to the high flexibility and low flow resistance of polyester fibers. Steel fibers with high strength and higher yield strength were used in hybrid form to solve this problem. It was revealed that the blend ratio that contributed the most to the mechanical behavior of the specimens was the case where the fibers were used as hybrid at a ratio of 1% by volume evaluation from both the experimental results and the optimization.
AtıfScopus4OpenAlex6İncele - MakaleAçık Erişim2025Scopus SJRQ4The effect of perceived scarcity of staple goods on stockpiling behaviour and impulse purchase intention and the mediating role of social media
Avci, Ibrahim
The research’s goal in this setting is to uncover the effects of consumers’ perceived scarcity of staple goods on impulse buy intention and stockpiling behaviour, as well as to determine the function of social media posts in mediating these effects. 594 consumers who had recently purchased staple goods from grocery stores participated in the survey. As a result of the structural equation model analysis, it was determined that perceived scarcity of staple goods has a positive effect on impulse purchase intention, stockpiling behaviour and social media. Finally, it was also determined that social media sharing has a mediating role on the effect of perceived scarcity of staple goods on impulse purchase intention and stockpiling behaviour. The findings obtained provide important theoretical and practical contributions.
AtıfScopus2OpenAlex3İncele - MakaleAçık Erişim2025Scopus SJRQ1Zircon U-Pb geochronology and Sr-Nd-Pb-Hf-O isotope signatures of Middle Eocene high-K plutons from the Eastern Pontides Orogenic Belt, NE Turkey: implications for parental magma sources and magmatic processes
Kaygusuz, Abdullah; Güloğlu, Zikrullah Samet; Aydınçakır, Emre; Yücel, Cem; Vural, Alaaddin; Saydam Eker, Çiğdem; Cicerali, Derya
The Eastern Pontides Orogenic Belt (EPOB) in northeastern Turkey is a well-preserved continental magmatic arc in the Alpine-Himalayan Orogenic Belt and contains many Eocene I-type high-K plutons. Employing LA-ICP-MS U-Pb zircon geochronology, the crystallization ages of the investigated Yaylalıköy and Taşbaşı plutons were established to be Lutetian (Middle Eocene), ranging from 47 Ma to 46 Ma. These plutons exhibit a compositional spectrum ranging from diorite to granodiorite, characterized by I-type, metaluminous, and high-K geochemical signatures. Notably, they are enriched in large-ion lithophile elements (LILEs) and light rare earth elements (LREEs), displaying pronounced negative Eu anomalies (EuN/Eu* = 0.58–0.96). Isotopic signatures reveal homogeneous and moderately low initial 87 Sr/86 Sr(i) ratios (0.704643–0.705034) and positive εNd(i) values (0.24 to 1.67) for the investigated plutons. These isotopic signatures are consistent with mantle origin, as evidenced by their position within the mantle array on isotope ratio diagrams. Lead isotope compositions exhibit limited variations, with initial ratios of 206 Pb/204 Pb(i) (18.55–18.64), 207 Pb/204 Pb(i) (15.61–15.64), and 208 Pb/204 Pb(i) (38.46–38.75). Zircon εHf(i) values are positive (2.32–6.20), plotting between the depleted mantle and chondritic evolution lines. Additionally, these rocks display low zircon δ18 O values (+4.54 to + 6.53‰), comparable to mantle composition. The petrographic characteristics of the investigated plutons suggest that fractional crystallization with minimal assimilation and/or magma mixing played a dominant role during their solidification. The integration of geochemical and isotopic data, alongside regional geological constraints, advocates for enriched lithospheric mantle as the source for the parental magmas of the studied plutons. These magmas subsequently underwent differentiation within a deep-seated magma chamber, followed by emplacement into the crust.
AtıfScopus5WoS6OpenAlex6İncele - MakaleAçık Erişim2025Scopus SJRQ1Paleolatitudinal movements of the eastern Sakarya Zone from Jurassic to Eocene
Kayın, Sercan; Hisarlı, Z. Mümtaz; İşseven, Turgay; Dokuz, Abdurrahman; Algur, Bahadırhan Sefa
The study area covers a region oriented north-south from the Black Sea coastline in the north to the Kelkit Basin in the south within the eastern Sakarya Zone in northern Türkiye. The objective of this study is to investigate the paleolatitudinal movements of the eastern Sakarya Zone during the Jurassic-Eocene time interval through paleomagnetism. Various volcanic and sedimentary units (e.g., the Şenköy, Berdiga, Mescitli, Çatak, Kızılkaya, and Çağlayan Formations) spanning the time interval from the Early Jurassic to Middle Eocene were identified. A total of 98 locations belonging to Early/Middle Jurassic to Eocene volcanic and sedimentary units were selected for paleomagnetic core sample collection. The samples were subjected to demagnetization through thermal and alternating field methods. Characteristic remanent magnetization directions (ChRM) were obtained. Isothermal remanent magnetization (IRM) and high temperature susceptibility (HTS) measurements were made to identify the minerals responsible for magnetization. To ascertain whether magnetization was acquired through rock formation or as a consequence of subsequent tectonic processes, conglomerate and fold tests were performed. The results showed that magnetization was acquired before folding, i.e., the rocks have primary magnetization. Polarity tests were also conducted using coeval normal and reverse polarity sites. The results indicate that the mean magnetization direction for the Early-Middle Jurassic is 18.1°/55.2° (D/I) and 3.3°/51.5° (D/I) for sedimentary and volcanic rocks, respectively, and 348.7°/46.7° (D/I) for Late Jurassic/Early Cretaceous sedimentary rocks. In the Late Cretaceous period, the mean magnetization direction is 8.0°/49.3° (D/I) and 9.1°/47.0° (D/I) for sedimentary and volcanic rocks, respectively. In the case of the Early/Middle Eocene, the mean magnetization direction is 348.6°/52.7° (D/I) and 5.9°/48.8° (D/I) for sedimentary and volcanic rocks, respectively. In this study, the E/I correction was applied to the Late Jurassic/Early Cretaceous sedimentary rocks, and paleolatitude data obtained from sedimentary rocks were also utilized. Our paleomagnetic results indicate that the eastern Sakarya Zone was situated at latitudes spanning from 27.9° to 35.7° during the Early Jurassic - Middle Eocene time interval. In consequence, the eastern Sakarya Zone constituted a portion of the southern margin of the Eurasian continent during the Late Jurassic and Middle Eocene periods.
- MakaleAçık Erişim2025Scopus SJRQ1The impact of photovoltaic panels on the environment and yield parameters in an open field agrivoltaic system: A case study in Ayaş, Ankara
Senturk, Bilge; Oylek, Yelda; Kanar, Zeynep Sevim; Celik, Ridvan; Kurtulus, Gunes; Ozden, Talat
Agrivoltaic systems represent an innovative approach that integrates energy production and agriculture by installing elevated photovoltaic modules over farmland. In this study, the critical parameters on microclimate and microenvironment conditions — soil moisture and temperature, relative humidity, ambient temperature, photosynthetically active radiation, wind speed — and crop yield amount were monitored and analyzed in a single axis tracking AgriPV system installed in Ankara, Türkiye. Results indicate that under the 35 % coverage AgriPV system, photosynthetically active radiation decreased by 38.55 %. Additionally, soil moisture was found to be higher at 20 cm below under the AgriPV system compared to the reference field during the plant growth period. The yield data showed a considerable difference in crop amount under the AgriPV system across different harvest periods. The results are critically important for developing models in future phases that aim to predict and optimize the agricultural and ecosystem performance of AgriPV systems.
AtıfScopus16WoS14OpenAlex12İncele - MakaleAçık Erişim2025Scopus SJRQ3A new class of robust ratio estimators for finite population variance
Zaman, Tolga; Bulut, Hasan
It is a general practice to use robust estimates to improve ratio estimators using functions of the parameters of an auxiliary variable. In this study, a new class of robust estimators based upon the Minimum Covariance Determinant (MCD) and the Minimum Volume Ellipsoid (MVE) robust covariance estimates have been suggested for estimating population variance in the presence of outlier values in the data set for the simple random sampling. The expression for the Mean Square Error (MSE) of the proposed class of estimators is derived from the first degree of approximation. The efficiency of the proposed class of robust estimators is compared with some competing estimators discussed in the literature, and found that proposed estimators are better than other mentioned estimators here. In addition, real data set and simulation studies are performed to present the efficiencies of the estimators. We demonstrate theoretically and numerically that the proposed class of estimators performs better than all other competitor estimators under all situations.
AtıfScopus8WoS14OpenAlex12İncele - MakaleAçık Erişim2025Scopus SJRQ1A strategy for the one-pot direct production of 5-hydroxymethylfurfural (HMF) from sucrose using organic weak acid in situ as a catalyst
Gül, Abdulkadir; Tanyıldızı, Muhammet Şaban
5-Hydroxymethylfurfural (HMF), which can be produced in high yields by acid-catalyzed dehydration of carbohydrates, is used as a feedstock in biofuel and biopolymer production. However, these acidic catalysts are usually added externally, which increases HMF production costs. Furthermore, other important parameters for high yields of HMF production are raw material selection, reaction medium, and separation-purification processes. The aim of this study is to produce HMF in one-pot without the addition of any exogenous catalyst by evaluating the fructose remaining in the production medium in which the glucose from sucrose hydrolysis is microbially fermented into gluconic acid (GA). HMF production from fructose in a biphasic system consisting of a fermentation liquid containing GA and fructose and 2-Methyltetrahydrofuran (2-MeTHF) was optimized using Central Composite Design (CCD). The variables examined included reaction time, reaction temperature, solvent type, salt type, and organic/aqueous phase ratio. In the study, by chelating GA and calcium ions, the low degree of ionization of GA was increased, and HMF was produced in high yields without the addition of a catalyst. Under optimum conditions, using 2-MeTHF/ fermentation liquid (6:1) and 7.56 wt% CaCl2, the yield of HMF produced in pressurized (hydrothermal) vessels at about 147 °C for 158 min reached 77.6 % of the theoretical yield. The amount of GA in the production medium was 92.64 % preserved from degradation. GA and HMF in different phases of the biphasic system were purified from the production medium in high yields. Furthermore, 2-MeTHF, which constitutes the organic phase of the biphasic system, was recovered at approximately 95 % by vacuum evaporation. As a result, HMF production from sucrose, which is a more economical and abundant raw material compared to glucose and fructose, was realized in one-pot without the addition of any catalyst.
AtıfScopus6WoS5OpenAlex7İncele - MakaleAçık Erişim2025Scopus SJRQ1The Protective Effect of Boric Acid Against High Fructose-Induced Liver and Kidney Damage in Rats
Yüksel, Duygu; Başeğmez, Mehmet; Kan, Fahriye
This study aimed to determine the protective role of boric acid (BA) in high fructose (HF)-induced liver and kidney toxicity in a young rat model. High-fructose consumption causes serious damage to liver and kidney tissue in healthy individuals and contributes to the emergence of various metabolic diseases. Thirty-two healthy female Wistar albino rats (250–300 g weight and 3–4 months) were randomly distributed into four equal groups (n = 8): control, high fructose % 20 (HF), boric acid 20 mg/kg (BA), and HF + BA. High fructose was freshly prepared and administered to the rats as 20 g of d-fructose dissolved in 100 mL of tap water daily for a duration of 30 days. Boric acid (20 mg/kg) was administered through gastric gavage throughout the 30-day study period. At the end of study, blood, liver, and kidney were collected from rats. The results indicated that high fructose induced increased glucose, total cholesterol, triglyceride, and urea levels in rat serum. Boric acid administration significantly decreased glucose, total cholesterol, triglyceride, and urea levels in HF + BA groups. The results indicated that high fructose-induced oxidative stress by increasing the level of MDA and by decreasing GSH levels, and CAT activity in the liver and kidney of rats. However, oral BA administration significantly decreased MDA levels and increased GSH levels, and CAT activity (p < 0.05). Furthermore, BA significantly reduced high fructose-induced histopathological and Immunohistochemistry alteration in the liver and kidney tissues. In conclusion, BA may prevent the oxidative imbalance and histopathological and immunohistochemical damage caused by high fructose in liver and kidney tissues in rats.
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İncele - MakaleAçık Erişim2025Scopus SJRQ2Some physical and mechanical properties of particle boards produced from industrial wood chips and Scots pine (Pinus sylvestris) cones
Karahan, Selim; Guler, Cengiz
This study investigated the potential use of Scots pine cones as an alternative raw material to larch wood chips for particle board production. Due to the increasing scarcity of forest resources, exploring alternative raw material for the forest industry has gained importance in in recent years. Particle boards were produced in laboratory conditions by blending industrial wood chips with Scots pine cones in varying proportions (25 %, 50 %, 75 % and 100 %) and usingr urea formaldehyde glue. The adhesice mixture contained 55 % urea formaldehyde glue and 33 % ammonium chloride as a hardener. Te production parameters included a press temperature of 150 °C, a press time was 7 minutes, and a press pressure of 2,4 MPa to 2,6 MPa. The resulting boards had a thickness of 16 mm and a density ranging from 730 kg/m3 to 740 kg/m3. Tests for thickness iswelling, water absorption, bending strength, modulus of elasticity and tensile strength perpendicular to the surface were conducted. Results showed that the physical and mechanical properties of the boards containing up to 25 % Scots pine cone met the required standards.
AtıfScopus2WoS2OpenAlex3İncele