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Active surface modification of thermoplastic polyurethane‐oleic acid nanocomposite fibers through alkali hydrolysis
No full textAbstractAlkali hydrolysis is a simple, low‐cost, and prominent surface modification method for developing more desirable scaffolds. In the presented study, two distinct concentrations (1 and 3 M) were predetermined for the hydrolysis treatments, and thermoplastic polyurethane (TPU) nanocomposite fibers with varying concentrations of oleic acid (OLE) were exposed. According to the scanning electron microscopy (SEM) images, when naked TPU or nanocomposite fibers showed any morphological changes, the interfacial bonding points of TPU‐OLE nanocomposite fibers enhanced in the higher concentrations of hydrolysis solution (1 and 3 M). The average fiber diameter in pure TPU is 0.59 ± 0.04 μm, while after doping with the highest concentration of OLE, the fiber diameter decreased to 0.48 ± 0.03 μm. Additionally, at the highest NaOH and OLE concentrations, the diameter decreased from 0.85 ± 0.02 μm in 3 M/TPU to 0.61 ± 0.04 μm in 3 M/TPU‐OLE3. Additionally, the surface hydrophilicity of TPU‐OLE fibers was noticeably improved through alkali hydrolysis, compared to the naked TPU approximately by 70%. Furthermore, the surface characterization of fibers revealed that the surface roughness values showed a significant change with increasing alkali concentration, but were not affected by the OLE concentration. All these findings indicate that TPU, whose surface wettability, roughness, and antibacterial response are modified by mercerization and OLE addition, can be safely and successfully used in tissue engineering applications.Highlights Polyurethane, oleic acid, and NaOH treatment were combined for tissue engineering applications. TPU/OLE nanofiber membranes were prepared by electrospinning. The surface of composite fibrillar membranes was modified alkali hydrolysis. The fiber diameter decreased after NaOH hydrolysis. Alkali hydrolysis improved the surface wettability and antibacterial response. </jats:sec
Ticari Bankacılıkta Kredi Tayınlaması: Sermaye Grupları Üzerine Nedensellik Analizi
No full textBu çalışma ticari bankacılık sektöründe kredi tayınlamasının geçerliliğini sermaye grupları bakımından test etmeyi amaçlamaktadır. Bu amaç ile 2010Q1-2022Q2 dönemi için bankaların sermaye durumlarına göre kamu sermayeli, özel sermayeli ve yabancı sermayeli bankalar olmak üzere üç panel oluşturulmuştur. Analiz yöntemi olarak Dumitrescu-Hurlin panel nedensellik testinin tercih edildiği bu çalışmada takipteki krediler/toplam krediler ve toplam krediler/toplam varlıklar değişkenleri kullanılmıştır. Analiz sonuçlarında yalnızca kamu sermayeli bankalar paneli için kredi tayınlamasının geçerliliğini destekleyici bulgulara ulaşılmıştır. Özel sermayeli ve yabancı sermayeli bankalar panelleri açısından kredi tayınlamasını destekleyici bulgulara ulaşılamamıştır. Analiz sonuçlarından hareketle kamu sermayeli bankalardan Halkbank ve Vakıfbank'ın analiz döneminde kredi tayınlamasına gittikleri görülmektedir.</jats:p
Supramolecular Solvent Based Microextraction with Sugaring-out Assisted Liquid-Liquid Extraction for the Determination of Fungicides in Honey
No full textMapping Left-Behind Regions: A Classification of Regional Disparities in Türkiye
No full textThis study examines regional disparities in Türkiye through the concept of "left-behind places," which has gained prominence in discussions on economic marginalization and political discontent. Despite the extensive literature on left-behind regions in the U.S., U.K., and Europe, Türkiye remains understudied. Using a Left-Behind Index (LBI) and K-means clustering analysis, this research identifies and classifies Türkiye’s NUTS2 regions based on long-term economic and demographic trends. The findings reveal persistent regional inequalities, characterized by an East-West divide and the economic underperformance of certain regions. Unlike Europe, where deindustrialization plays a crucial role, Türkiye’s left-behind regions are primarily defined by economic stagnation, population decline, and outmigration. The results underscore the need for targeted regional policies to address disparities. This study contributes to the broader discourse on left-behind places by providing empirical insights into Türkiye’s unique socio-economic landscape.</jats:p
Analgesia Nociception Index Monitoring in Management of Perioperative Analgesia in Total Knee Arthroplasty Surgeries with Femoral Nerve Block
No full textBackground and Objectives: The aim of our study is to determine the effects of analgesia nociception index (ANI) monitoring on intraoperative opioid consumption, postoperative analgesia, and the recovery unit length of stay in patients with a preoperative femoral nerve block (FNB) undergoing total knee arthroplasty (TKA) surgery under general anesthesia. Materials and Methods: Seventy-four patients in the American Society of Anesthesiologists Physical Status (ASA-PS) I-III scheduled for TKA under general anesthesia were included in this study. After FNB, the patients were divided into two groups (control group (n = 35)–ANI group (n = 35)). After standard anesthesia induction in both groups, maintenance was conducted using sevoflurane and remifentanil infusion with a bispectral index (BIS) between 40 and 60. In the control group, the intraoperative remifentanil infusion dose was adjusted using conventional methods, and in the ANI group, the dose was adjusted using ANI values of 50–70. The duration of operation, duration of surgery, extubation time, tourniquet duration and pressure, and the amount of remifentanil consumed intraoperatively were recorded. Results: Intraoperative remifentanil consumption was lower in the ANI group compared to the control group (p = 0.001). The time to reach a Modified Aldrete Scale score (MAS) ≥ 9 was shorter in the ANI group (p < 0.001). NRS scores in the recovery unit and 4, 8, 12, and 24 h postoperatively were lower in the ANI group compared to the control group (p = 0.006, p < 0.05). There was a weak significant inverse relationship between the last ANI values measured before extubation and NRS scores in the postoperative recovery unit (r: −0.070–0.079, p: 0.698–0.661). No difference was observed between the groups in other data. Conclusions: In patients undergoing TKA with FNB under general anesthesia, ANI monitoring decreased the amount of opioids consumed intraoperatively and postoperative pain scores and shortened the length of stay in the recovery unit. We suggest that ANI monitoring in intraoperative analgesia management may be helpful in determining the dose of opioid needed by the patient and individualized analgesia management.</jats:p
Health literacy and successful aging in older adults: A predictive correlational design
No full textThis study aimed to measure health literacy and successful aging level and their predisposing factors among older adults.A predictive correlational design was performed. The study was completed with 450 older individuals, resulting in a participation rate of 94.9 %.The risk of inadequate and limited health literacy was higher in older adults who were single (3.4 times), those with chronic diseases (2.93 times), and those with medium/poor health perception (3.1 times). A multiple regression model consisting of age, health perception, and health literacy level explained 22 % of the variance in successful aging.The study concluded that health literacy and successful aging were predictive factors of each other. Marital status, education level, having chronic disease, regular medication use, and health perception predicted the health literacy level. Moreover, age, health perception, and health literacy level are significant predictors of successful aging
Effect of conventional and digital fabrication techniques on marginal and internal fit of lithium disilicate endocrowns
No full textThis study aims to compare the marginal and internal fit of lithium disilicate endocrowns produced by conventional and/or digital impression and fabrication techniques.Endocrown preparations were performed on 40 mandibular first molars. The teeth were divided into four groups (n = 10) based on the impression and fabrication technique; CON: conventional impression/manuel wax patterns/heat-pressed endocrowns, DCD: digital impression/CAD-CAM milled wax patterns/heat-pressed endocrowns, D3D: digital impression/3D printed resin patterns/heat-pressed endocrowns, DC: digital impression/digital design/CAD-CAM milled endocrowns. The marginal and internal fits of the endocrowns were measured by using the silicon replica technique and stereomicroscope with 57x magnification. The statistical analysis was carried out using the Kruskal-Wallis and paired two-sample t-tests. The significance level was set at p < 0.05.Marginal fit measurements revealed the following; CON: 111 μm, DCD: 96 μm, D3D: 91 μm, and DC: 93 μm. A statistically significant difference was found between the CON group and the other groups in the marginal fit measurement. Internal fit measurements revealed the following; CON: 120.75 μm, DCD: 112 μm, D3D: 114.88 μm, and DC: 122 μm. There was a statistically significant difference between the CON group and the DCD group in the internal fit measurement, while no significant difference observed between the other groups.It is concluded that all endocrowns had a clinically acceptable marginal and internal fit. The use of digitally generated patterns, CAD-CAM milled or 3D printed, in the fabrication of endocrowns can be effective in producing restorations with improved marginal and internal adaptation.The use of digital production methods can improve the marginal and internal adaptation of endocrown restorations
Türkiye Yüzyılı Maarif Modeli Okul Öncesi Eğitim Programının Hassas Beceriler Açısından İncelenmesi
No full textHassas beceriler, kişilik, tutum kişisel gelişim, sosyal katılım, sosyal-duygusal ve davranışla ilgili beceriler, yetenekler ve özellikler olarak tanımlanmaktadır. Hassas beceriler; sosyal veya kişilerarası, bilişsel beceriler ve duygu odaklı başa çıkma becerileri kapsamında değerlendirilmektedir. Bu becerileri kazanmanın belli bir yöntemi olmamakla birlikte kişinin kendi özelliklerinin farkına vararak, yetenekli olduğu alanlara hâkimiyetini arttırması ve zayıf olduğu alanlarda ise kendini geliştirecek hedefler koyması hassas becerilerin edinilmesi için oldukça önemlidir. Bu becerilerin kazanılması için okul öncesi eğitim dönemi güzel bir başlangıç olacaktır. Bu nedenle, araştırmanın amacı Türkiye Yüzyılı Maarif Modeli Okul Öncesi Eğitim Programı’nı hassas beceriler açısından incelemektir. Araştırmada eğitim programının alan becerilerine ait öğrenme ve alt öğrenme çıktıları, Mangrulkar, Whitman ve Posner (2001)’in ortaya koyduğu hassas beceriler sınıflamasına göre incelenmiştir. Araştırma doküman incelemesine dayalı olarak yürütülmüştür. Araştırmadan elde edilen bulgulara göre öğrenme ve alt öğrenme çıktılarının; empati, problem çözme ve karar verme ve öz güven becerilerinde yoğunlaştığı görülmüştür. Okul öncesi öğrencilerin yetkinliklerini geliştirmeleri açısından büyük bir önem taşıyan hassas becerilerine programda yeterince ve dengeli yer verilmediği belirlenmiştir. Araştırmanın bulguları doğrultusunda hassas becerilerin kazandırılmasına yönelik öğretim programlarında daha fazla yer verilmesine yönelik öneriler getirilmiştir.</jats:p
Phytochemical investigation and assessment of the anti-inflammatory activity of four Heracleum taxa growing in Turkey
No full textIntroductionHeracleum L. has been known as “hogweed” and used for inflammatory diseases, including fever, enteritis, and bronchitis, for many years worldwide. The Heracleum genus is also prominently recognized for its high content of coumarins, which are considered a significant group of natural compounds known for their noteworthy anti-inflammatory properties.MethodsThe present study evaluated the anti-inflammatory activity of dichloromethane and methanolic extracts from H. paphlagonicum, H. sphondylium subsp. ternatum, H. sphondylium subsp. elegans, and H. sphondylium subsp. cyclocarpum (100 mg/kg), which have not been previously investigated for their anti-inflammatory properties. Inflammation models induced by carrageenan, prostaglandin E2, and serotonin were employed to evaluate anti-inflammatory activity, using indomethacin (10 mg/kg) as the reference standard. Statistical differences between treatment and control groups were evaluated using ANOVA with Student-Newman-Keuls post-hoc tests. Additionally, the coumarin contents of the extracts were quantified as mg/g by high-performance liquid chromatography.Results and discussionH. sphondylium subsp. cyclocarpum roots displayed the highest inhibition for carrageenan, prostaglandin E2, and serotonin-induced hind paw edema, with inhibition ranges of 22.8%–36.9%, 5.4%–35.7%, and 3.9%–17.9%, respectively, while the inhibition ranges for indomethacin were 12.8%–44.3%, 2.7%–41.3%, and 7.1%–30.6%, respectively. The highest bergapten and imperatorin quantities were found in H. sphondylium subsp. cyclocarpum roots (0.49% and 0.14%) and in H. sphondylium subsp. elegans roots, which had the highest xanthotoxin level (0.06%). Angelicin was detected in H. paphlagonicum, H. sphondylium subsp. elegans, and H. sphondylium subsp. cyclocarpum roots at concentrations of 0.04%, 0.04%, and 0.02%, respectively. The correlation between the highest inhibitory activity observed in H. sphondylium subsp. cyclocarpum roots and the elevated levels of coumarins, particularly bergapten and imperatorin, suggests a potential link between coumarin concentration and anti-inflammatory effects. Additionally, our findings support the traditional use of this genus for treating inflammatory disorders. Further investigations are necessary to identify the active compounds and elucidate the mechanisms of action of these plants, potentially leading to the discovery of novel therapeutic options for the treatment of inflammation.</jats:sec
A Qualitative Analysis on the Definition of Zakat in the Turkish Tax System and Institutionalization of Zakat
No full textFew studies research about zakat and tax system in Türkiye. This research discusses the institutionalization of zakat in Türkiye and the tax advantages that could be provided for zakat payments. A qualitative method and semi-structured interviews are preferred in the research. Accordingly, interviews are conducted with 21 income taxpayers who pay zakat. Participants were asked about their definition of zakat, methods they use when giving zakat, their perspectives on the definition and institutionalization of zakat in the tax system and their thoughts on tax advantages that could be provided for zakat. The results show that 14 participants consider the institutionalization of zakat necessary. All participants emphasized that the institutional structure should ensure trust and transparency principles. 13 out of 21 participants stated that institutionalization should be done by the state, while 10 stated that a different system established by the state should be implemented. 5 participants expressed views against the institutionalization of zakat by the state. 12 participants expressed their desire for zakat to be defined in the Turkish tax system but expressed hesitation regarding the provision of tax advantages; 8 participants emphasized the necessity of providing tax advantages. As a result, it is thought that the institutionalization of zakat in Türkiye may reduce the impact of social transfer expenditures on the budget.</jats:p