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Phyllanthus emblica yüklü yara örtüsü malzemeleri
No full textFen Bilimleri Enstitüsü, Biyomühendislik Ana Bilim DalıAntik çağlardan beri bitkiler, çeşitli hastalık ve rahatsızlıklar için terapötik yaklaşımlarda hayati bir rol oynamıştır. Phyllanthus emblica'nın (P. emblica) birçok çalışmada çoklu terapötik aktivitelere sahip olduğu tanımlanmıştır ve Ayurvedik ve Unani tıbbi sistemlerinin önemli bir parçası olarak kabul edilir. Bu çalışma, sentezlenen P. emblica yüklü kriyojellerin yara iyileşmesi üzerindeki etkilerini ve yara pansuman uygulamalarındaki potansiyellerini incelemeyi amaçlamıştır. Bu amaçla, %0,5 (PVA/Gel/P.emblica-0,5), %1 (PVA/Gel/P.emblica-1), %1,5 (PVA/ Jel/P.emblica-1.5), %2 (PVA/Gel/P.emblica-2) P. emblica içeren polivinilalkol/jelatin (PVA/Gel) kriyojeller sentezlenmiştir. Karakterizasyon çalışmaları kapsamında şişme testleri, Brunauer-Emmett-Teller (BET) ve morfoloji analizleri yapılmıştır. Sentezlenen kriyojellerin yara pansuman malzemesi olarak uygunluğunu göstermek amacıyla HaCaT hücreleri kullanılarak in vitro hücre kültürü çalışmaları yapılmıştır. Şişme testleri ve BET analizi sonuçları, P. emblica yüklü PVA/Jel kriyojellerinin P. emblica miktarlarının artmasıyla arttığını kanıtlamıştır. Morfolojik sonuçlar, kriyojellerin yoğun, birbirine bağlı gözenek morfolojisine ve makro gözenekli bir yapıya sahip olduğunu göstermiştir. 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazolyum bromür (MTT), tripan mavisi deneyi ve canlı ölü boyama verileri, P. emblica'nın kriyojellere eklenmesinin hücre proliferasyonunun artmasına, hücre sayısının artışına ve hücre canlılığının yükselmesine yol açtığını göstermiştir. P. emblica yüklü kriyojeller üzerindeki HaCaT hücrelerinin faz kontrast mikroskop, taramalı elektron mikroskobu (SEM), immünofloresan ve giemsa görüntülerine dayanarak, P. emblica'nın hücre tutunmasını, çoğalmasını ve penetrasyonunu desteklediği gözlenmiştir. Sonuç olarak, PVA/Gel/P.emblica kriyojellerinin yara örtüsü malzemesi olarak kullanıma uygun olduğunu ve ileri çalışmalarla geliştirilebileceği gösterilmiştir.Since ancient times, plants have played a vital role in therapeutic approaches for a variety of diseases and ailments. Phyllanthus emblica (P. emblica) has been described in many studies to have multiple therapeutic activities and is considered an important part of Ayurvedic and Unani medicinal systems. This study sought to examine the efficacy of synthesized Phyllanthus emblica loaded cryogels on wound healing and their potential in wound dressing applications. For this purpose, polyvinylalcohol/gelatin (PVA/Gel) based cryogels were synthesized containing 0.5% (PVA/Gel/P.emblica-0.5), 1% (PVA/Gel/P.emblica-1), 1.5% (PVA/Gel/P.emblica-1.5), 2% (PVA/Gel/P.emblica-2) P. emblica extract. Swelling tests, Brunauer-Emmett-Teller (BET) and morphology analysis were conducted within the scope of characterization studies. In-vitro cell culture studies were performed using HaCaT cells to illustrate the suitability of the synthesized cryogels as wound dressing material. The swelling tests and BET results revealed that P. emblica loaded PVA/Gel cryogels was increased with increasing the amounts of P. emblica. Morphological results displayed that the cryogels had an dense, interconnected pore morphology and a macroporous structure. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), trypan blue exclusion and live-dead assay results revealed that adding of P. emblica into cryogels led to enhanced cell proliferation, increased cell number, and improved cell viability. Based on the phase contrast microscope, scanning electron microscope (SEM), immunofluorescence and giemsa images of the HaCaT cells on P. emblica loaded PVA/Gel cryogels, it was observed that P. emblica promoted cell attachment, proliferation and penetration. In conclusion, it has been shown that PVA/Gel/P.emblica cryogels are suitable for use as wound dressing materials and can be developed with further studies
Seçilmiş firmaların temettü indirim modeli ile değerlemesi: Borsa İstanbul'da bir uygulama
No full textSosyal Bilimler Enstitüsü, İşletme Ana Bilim Dalı, Finans Bilim DalıBu tez çalışmasının amacı, 2022 yılı için Türkiye'de faaliyet gösteren ve Türkiye Borsalarında işlem goren küçük ve büyük sermayeli şirketlerin, yatırımcı duyarlılığı teorisinin öngördüğü şekilde, içsel ve piyasa değerleri arasındaki sapmaların, küçük sermayeli şirketler lehine daha yüksek olup olmadığını araştırmaktır. Şirketlerin içsel değerleri karpayı indirgeme modeli ile hesaplanmış ve iki grup arasındaki sapmaların istatistiksel olarak anlamlı olup olmadığı Welch's t-testi ile analiz edilmiştir. İki grup arasında, tanımlayıcı istatistiklerde, ortalamalar ve varyanslar da fark görülmesine rağmen, Welch t-Testi sonuçları ortalamaların farklı olduğu hipotezinin Kabul edilemediğini ortaya koymuştur.This thesis study aims to calculate the deviations between the intrinsic values and the market prices of selected firms, quoted in Turkish Exchange marketsin 2022 to detect if there is mispricing due to small firm anomaly, as the investor sentiment theory suggests so. Intrinsic values are calculated with the dividend discount model and the significance of differences between the two groups are analyzed by Welch's t-Test. Although the difference in means and variances can be seen in the descriptive statistics, the difference in means seemed insignificant when Welch's t-test was employed
Melissa officinalis essential oil loaded polycaprolactone membranes: evaluation of antimicrobial activities and cytocompatibility for tissue engineering applications
No full textAntimicrobial biomaterials play important role in tissue engineering applications to protect damaged tissue from infections. The aim of this study is producing antimicrobial polycaprolactone (PCL) membranes by using a plant based antimicrobial agent. Therefore,Melissa officinalisessential oil (MEO) was investigated against ten types of microorganisms and remarkable antimicrobial activity was demonstrated. PCL:MEO membranes were prepared by solvent casting method by mixing MEO into PCL in various ratios (PCL:0M, PCL:0.25M, PCL:0.5M, and PCL:1M w/w). Water contact angle measurements showed that hydrophilicity of the membranes increased with increasing concentrations of MEO from 103.44 degrees to 83.36 degrees for PCL:0M and PCL:1M, respectively. It was determined that there was an inverse relationship between the MEO concentration and the mechanical properties. Notable antioxidant activity of PCL/MEO membranes was exhibited by the inhibition percent of 2,2-diphenyl-1-picrylhydrazyl (DPPH) which was increased from 24.74% to 44.79% for PCL:0M and PCL:1M, respectively. The antimicrobial activity of MEO was also highly maintained in PCL membranes. For PCL/MEO membranes, at least 99.9% of microorganisms were inhibited. Cytocompatibility of the membranes were investigated by resazurin assay, scanning electron microscopy analysis and 4',6-diamidino-2-phenylindole (DAPI) staining. PCL:0.25M and PCL:0.5M membranes supported the viability of L929 cells more than 87% when compared to PCL:0M membranes on day 6. However, the viability of L929 cells on PCL:1M membranes was about 43% indicating significant decrease on cellular activity. In conclusion, PCL:0.25M and PCL:0.5M membranes with their high antimicrobial activity, acceptable mechanical properties and cytocompatible properties, they can be considered as an alternative biomaterial for tissue engineering applications.Scientific Research Projects Unit of Adana Alparslan Turkes Science and Technology University [BAP- 21103012]; Scientific and Technological Research Council of Turkiye [TUBITAK 2209A/1919B012003944]This study was supported by the Scientific Research Projects Unit of Adana Alparslan Turkes Science and Technology University (BAP- 21103012) and The Scientific and Technological Research Council of Turkiye (TUBITAK 2209A/1919B012003944)
Pathways from education and childhood parental death to successful aging: the role of social conditions and perceived income level
No full textObjectives Although the association between adverse childhood conditions and health in later life has been relatively well established, little is known about how and through which mechanism this association develops. Building on the developmental adaptation model (Martin & Martin, 2002), the present study investigates the effects of distal and proximal influences on successful aging (SA). Methods A cross-sectional survey was conducted of 475 adults aged 50 and above (Mean age = 72.13, SD = 10.46). SA was measured based on Rowe and Kahn's successful aging criteria model (1997) and an SA operationalization based on a number of multidimensional biopsychosocial indicators, including no disease and disability, active engagement with life, high physical and cognitive functioning, psychological well-being, life satisfaction and a one-item subjective SA question. Results Parental death had no direct effect on SA (beta = .03, p = .629), whereas education had (beta= .39, p < .001). Furthermore, perceived income level and social conditions were identified as two sequential mediators between both education and SA; and parental death and SA. Conclusions The findings suggest that both early life and current factors contribute to explaining SA in a variety of ways
The effects of the Presidential Government System on the health sector: The case of Adana province
No full textLisansüstü Eğitim Enstitüsü, Siyaset Bilimi ve Kamu Yönetimi Ana Bilim DalıHükümet sistemleri ve anayasal hareketler Türk siyasal hayatında önemli yer tutan unsurların başında gelmektedir. Cumhuriyetin kurulmasından günümüze kadar geçen sürede yönetimsel gelişmeler ve anayasal hareketler toplumsal hayatı etkilemiş, aynı zamanda devletin kurumsal ve yapısal kimliğini belirlemiştir. Halen yürürlükte olan 1982 anayasasında da son dönemde birtakım değişiklikler meydana gelmiştir. Özellikle 16 Nisan 2017'de gerçekleştirilen anayasa değişikliği referandumu bu duruma örnek teşkil etmektedir. Bu referandumla Cumhurbaşkanlığı Hükümet Sisteminin (CHS) yasal altyapısını oluşturan değişiklikler kabul edilmiş ve 24 Haziran 2018 seçimleriyle de CHS fiilen hayata geçmiştir. Yeni sisteme geçişle birlikte devlet organları yeniden şekillendirilmiştir. Özellikle bakanlıkların teşkilat yapısı başta olmak üzere kurum ve kuruluşlarda yapısal düzenlemeler gerçekleşmiştir. Benzer şekilde Sağlık Bakanlığı ve bağlı kuruluşlarında da birtakım değişiklikler yaşanmıştır. Hazırlanan bu tezde CHS'nin sağlık sektörüne etkileri incelenmiş ve bu kapsamda Adana Şehir Eğitim ve Araştırma Hastanesi'nde görevli sağlık personelleri ve idari personellerle yarı yapılandırılmış görüşmeler yapılmıştır. CHS sonrası sağlık sektörü incelenirken yapılan görüşmelerin yanı sıra sağlık istatistikleri yıllığı ve stratejik planlardan yararlanılmıştır. Sağlık Bakanlığı faaliyet raporları incelenmiş, stratejik planlar değerlendirilmiştir. Bu incelemeler ve yapılan görüşmeler sonucunda CHS sonrası sağlık hizmetlerinde birtakım değişimler meydana geldiği sonucuna ulaşılmıştır. Ayrıca CHS ile yönetimsel birtakım değişimlerin yaşandığı ve bu kapsamda sağlık hizmetlerinde bazı gelişmelerin meydana geldiği sonucuna ulaşılmıştır.Government systems and constitutional movements are among the critical elements in Turkish political life. Administrative developments and constitutional movements have affected social life since the establishment of the Republic and determined the institutional and structural identity of the state at the same time. There have been some changes recently in the 1982 constitution, which is still in force. In particular, the constitutional amendment referendum held on 16th April 2017, exemplifies this situation. With this referendum, the changes constituting the legal infrastructure of the Presidential Government System (PGS) were accepted and with the 24th June 2018 elections, the PGS was actually implemented. With the transition to the new system, state organs were reshaped. Structural arrangements have been made in institutions and organizations, especially in the organizational structure of the ministries. Similarly, there have been some changes in the Ministry of Health and its subsidiaries. In this thesis, the effects of the PGS on the health sector were examined, and in this context, semi-structured interviews were conducted with the health personnel and administrative personnel working in Adana City Training & Research Hospital. In addition to the interviews made while examining the health sector after the PGS, health statistics yearbooks and strategic plans were used. Ministry of Health activity reports were examined, and strategic plans were evaluated. As a result of these examinations and interviews, it has been concluded that some changes have occurred in health services after the PGS. Additionally, it has been concluded that some administrative changes have been experienced with the PGS, and within this context, some developments have occurred in health services
Development and Validation of Secularity Scale for Muslims
No full textThere is currently no secularity scale with strong psychometric properties that would allow for the examination of the secularization process experienced by Muslims. Thus, the purpose of this article is to develop a psychometrically sound and quick-to-apply scale that can be used to measure the degree of secularity among Muslims. For exploratory factor analysis (EFA), an inventory with 65 items was applied to 1,573 university students, and it yielded a two-factor structure with an internal reliability of 0.975 for Daily Life factor and 0.952 for Faith and Prayer factor. After EFA, the confirmatory factor analysis (CFA) was performed with 4,391 individuals, and a structure that can be deemed very solid was found. The measurement invariance was also examined, and it was discovered that the scale can be used for various populations. In addition, the scale has convergent validity, a high test-retest result, and discriminant validity. The 25-item Secularity Scale has a new theoretical approach - which is not only based on faith and prayer but also daily life activities - and sound psychometric properties. Examining how secularity manifests itself in Muslim societies might be useful in describing, predicting, and explaining how individuals act in a variety of contexts. The scale might also help to avoid the use of approach utilized in Christian-centred secularity debates in the case of Muslim-majority societies
Theoretical Investigation of Heat Capacities as a Function Temperature of Stannous Selenide (SnSe) Using Einstein-Debye Approximation
No full textA new alternative approach has been suggested for evaluating the heat capacities of stannous selenide (SnSe), based on the Einstein-Debye approximation. It is well known the thermal behavior of solids is a very important theoretical problem that has been explored thoroughly with the development of Einstein, Debye and recently developed Einstein-Debye approximations. Many additional thermophysical characteristics of materials may be analyzed using the Einstein-Debye approach employed in this study. As an application, the heat capacities have been computed by using the Einstein-Debye method for SnSe in the temperatures range between 40 and 900 K. The temperature dependence of heat capacities have been computed and found to be in good accord with the literature throughout a wide temperature range
Day-ahead electricity price forecasting using artificial intelligence-based algorithms
No full text2023 International Conference on Innovation and Intelligence for Informatics, Computing, and Technologies, 3ICT 2023 -- 20 November 2023 through 21 November 2023 -- Virtual, Online -- 196787Deregulation and privatization of electricity markets has brought greater attention to electricity price forecasting (EPF) problem in day-ahead and intraday markets since a reliable forecast ensures market participants develop bidding strategies that aim to maximize their profit. Nonlinear and non-stationary characteristics of electricity prices ensemble a barrier in front of an accurate forecast and have required researchers to analyze the effects of exogenous variables such as economic metrics and neighboring countries' prices. In this paper, three different artificial intelligence-based algorithms namely multiple linear regression (MLR), autoregressive integrated moving average (ARIMA) with exogenous variables, and extreme gradient boosting decision trees (XGBoost) are applied to forecast day-ahead electricity prices of the Turkish electricity market by considering the aforementioned exogenous variables. Test results have shown that the XGBoost model has superior results in the error metrics than the other employed methods. Substantial error decrease in symmetric mean absolute percentage error, normalized root mean square error, normalized mean absolute error, and mean absolute scaled error metrics by 19.256%, 19.834%, 23.060%, and 23.016% is observed with respect to the closest performing MLR method on the test set. © 2023 IEEE
Estimated Fuel Properties of Luffa Aegyptiaca as a Possible Feedstock for Biodiesel Production
No full textThe world's expanding human population and rising standard of living result in a rise in energy consumption. Since fossil fuel reserves are mostly exploited to fulfil the expanding energy demand, this makes it more difficult to get energy. Due to the non-renewable nature of fossil fuel resources and the possibility of energy supply issues occurring as a result of globalization, access to energy becomes challenging at this point. However, switching to alternative and environmentally beneficial fuel sources is now a need because of the harm that their widespread usage has caused to the environment and the diminishing resources that are being used up. The loofah seed Luffa Aegyptiaca, which is grown mostly in Turkey's Hatay region, is discussed in this paper. Fatty acids in the oil produced from Luffa aegyptiaca seeds were identified by analysis. Oleic and linoleic acids were found to be the primary fatty acids controlling the combustion characteristics of biodiesel fuel. These acids were found to be, respectively, 97.8318 and 129.1163. Using the Biodiesel Analyzer v1.2, the physicochemical characteristics of biodiesel fuel were identified. It was determined that biodiesel fuel made from Luffa aegyptiaca seed might be used as a substitute for diesel fuel
The Effect of Sage (Salvia sclarea) Essential Oil on the Physiochemical and Antioxidant Properties of Sodium Alginate and Casein-Based Composite Edible Films
No full textThe aim of this study was to examine the effect of Sage (Salvia sclarea) essential oil (SEO) on the physiochemical and antioxidant properties of sodium alginate (SA) and casein (CA) based films. Thermal, mechanical, optical, structural, chemical, crystalline, and barrier properties were examined using TGA, texture analyzer, colorimeter, SEM, FTIR, and XRD. Chemical compounds of the SEO were identified via GC-MS, the most important of which were linalyl acetate (43.32%) and linalool (28.51%). The results showed that incorporating SEO caused a significant decrease in tensile strength (1.022-0.140 Mpa), elongation at break (28.2-14.6%), moisture content (25.04-14.7%) and transparency (86.1-56.2%); however, WVP (0.427-0.667 x 10(-12) g center dot cm/cm(2)center dot s center dot Pa) increased. SEM analysis showed that the incorporation of SEO increased the homogeneousness of films. TGA analysis showed that SEO-loaded films showed better thermal stability than others. FTIR analysis revealed the compatibility between the components of the films. Furthermore, increasing the concentration of SEO increased the antioxidant activity of the films. Thus, the present film shows a potential application in the food packaging industry.TRC [BFP/RGP/HSS/22/007]This study was supported by TRC grant number BFP/RGP/HSS/22/007