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The effect of sodium pyrithione in acute periods on ghrelin and leptin hormone levels in rats
No full textBu tez çalışmasında akut süre dilimlerinde (24 ve 96 saat) sodyum pirition (NaPT) ve salin uygulanılması sonucunda Wistar albino sıçanlarda kan serumu ghrelin ve leptin hormon seviyeleri araştırılmıştır. Çalışmalar neticesinde kontrol grupları ile doz gruplarının karşılaştırılması yapılmıştır. Karşılaştırma sonucunda uygulanan her iki doz grubundaki (35 ve 70 mg/kg) akut sürelerde ghrelin hormon seviyelerindeki azalma istatistiksel analizler sonucunda farkın önemli olduğu tespit edilmiştir. Yine bu çalışmada uygulanan doz gruplarının (35 ve 70 mg/kg) kontrol grubu ile karşılaştırılması sonucu akut sürelerde leptin hormon seviyesindeki artışın istatistiksel analizler sonucunda farkın önemli olduğu tespit edilmiştir. Benzer zaman dilimlerindeki dozlar arasındaki leptin ve ghrelin hormon seviyelerindeki farklar önemsiz olduğu belirlenmiştir. 24 ve 96 saatlik sürede uygulanmış aynı NaPT dozları arasında farklar önemsizdir. Sıçanlar uygulanılmış olan NaPT dozları sitotoksik etki oluşturduğu ve sonucunda doku hasarı oluşturarak nekroz geliştirmiş ve bunun sonucu gelişen inflamasyonun hayvanlarda immünolojik tepki olarak TNF-alfa, 1β ve IL-6 salınımının yapıldığı bilinmektedir. Bu salınan proinflamatuvar sitokinlerin kaşektik etkisi sonucu ghrelin hormon seviyelerinde azalmaya ve leptin hormon seviyelerinde artış tespit edilmiştir.In this thesis study, blood serum ghrelin and leptin hormone levels were investigated in Wistar albino rats after administration of sodium pyrithione (NaPT) and saline in acute periods (24 and 96 hours). As a result of the studies, the comparison of the control groups and dose groups was made. As a result of the comparison, the decrease in ghrelin hormone levels in the acute periods in both dose groups (35 and 70 mg/kg) was found to be significant as a result of statistical analyzes. Again, as a result of the comparison of the dose groups (35 and 70 mg/kg) administered in this study with the control group, the difference in the increase in leptin hormone levels during the acute periods was found to be significant as a result of statistical analysis. The differences in leptin and ghrelin hormone levels between doses at similar time periods were found to be insignificant. The differences between the same doses of NaPT administered over a 24-hour and 96-hour period are insignificant. It is known that NaPT doses administered to rats have cytotoxic effects, resulting in tissue damage and necrosis. As a result of the cachectic effect of these released proinflammatory cytokines, a decrease in ghrelin hormone levels and an increase in leptin hormone levels were detected
Construction of a pretentious lifestyle in the context of postmodernism through social media: The example of Instagram
No full textTüketim pratiklerinin farklılaşması, ihtiyaçların karşılanacağı tüketimden ziyade kişileri sürekli olarak daha fazlasına yönlendirmektedir. Bu sebeple bireylerin kendilerini diğer kişilere ispat etme, statülerini gösterme, saygınlık kazanma, takdir edilme amacıyla tükettikleri lüks ürün ve eşyaları "teşhir" yoluyla sergilemeleri olan gösterişçi tüketim pratikleri giderek artmaktadır. Dünya genelinde internet kullanımının yaygınlaşması, sosyal medya araçlarının daha fazla görünür olmasını ve farklı amaçlar doğrultusunda kullanılmasını da beraberinde getirmiştir. Bu anlamda sosyal medya, bireylerin gösterişçi tüketim faaliyetlerini sergileyebilecekleri en uygun mecralardan birini temsil etmektedir. Bu şekilde bireyler hayatlarını diğerlerine rahatlıkla teşhir etme imkânına kavuşmuştur. Çalışmada postmodernizm bağlamında gösterişçi tüketim pratiklerinin Instagram'daki örnekleri incelenmiştir. Bu bağlamda Influencerların bir şeyleri ispat etme, saygınlık ve prestij kazanma amacıyla paylaştıkları lüks ürünlerin Instagram'da ne şekilde sergilendiği ele alınmıştır. Çalışmanın amacı, Veblen'in gösterişçi tüketim kavramının günümüzde dijitalleşmenin de etkisiyle sosyal platformlara taşındığını ve bunun en belirgin örneklerinden birinin de Instagram mecrası olduğunu ortaya koymaktır. Çalışmanın ilk bölümünde postmodernizm kavramı ele alınarak postmodern dönemin özellikleri ve önde gelen temsilcileri ele alınmıştır. İkinci bölümde gösterişçi tüketim tarzları ele alınarak, gösterişçi tüketimin özellikleri, faktörleri ve etkenleri açıklanmıştır. Çalışmanın araştırma bölümünde ise amaçlı örneklem yoluyla belirlenen 12 Instagram hesabı üzerinde içerik analizi uygulanmıştır. Yapılan araştırma sonucunda Instagram'ın gösterişçi tüketim pratiklerinin sergilendiği bir platform olduğu ve kullanıcılarda tüketim tercihleri noktasında bir karşılığının olduğu saptanmıştır.The differentiation of consumption practices constantly directs people to more consumption than that will meet their needs. Because of this, conspicuous consumption practices, which are the display of luxury products and goods that individuals consume in order to prove themselves to others, to show their status, to gain prestige and to be appreciated, are increasing. The widespread use of the internet around the world has brought social media tools to be more visible and used for different purposes. In this sense, social media represents one of the most suitable channels where individuals can exhibit their conspicuous consumption activities. In this way, individuals have the opportunity to easily expose their lives to others. In the study, examples of conspicuous consumption practices on Instagram in the context of postmodernism are examined. In this context, the study discusses how the luxury products shared by the influencers in order to prove something, gain respect and prestige are displayed on Instagram. The aim of the study is to reveal that Veblen's concept of conspicuous consumption has moved to social platforms with the effect of digitalization and one of the most prominent examples of this is Instagram. In the first part of the study, the concept of postmodernism is discussed and the characteristics and prominent representatives of the postmodern period are discussed. In the second part, conspicuous consumption styles are discussed and the characteristics, factors and agents of conspicuous consumption are explained. In the research part of the study, content analysis was applied on 12 Instagram accounts determined by purposeful sampling. As a result of the research, it has been determined that Instagram is a platform where conspicuous consumption practices are exhibited and that it has an influence over the consumption preferences of users
Design and analysis of a natural gas fuel cogeneration system: Aksaray University case
No full textBu çalışmada, Aksaray Üniversitesinin enerji verimliliğini üst düzeyde kullanabilmek amacı ile üniversitenin enerji ihtiyacına göre kojenerasyon sistemi ekonomik analizi yapılmıştır. Dünyada artan nüfus, teknolojik ilerlemeler ve insanların modern şartlarda yaşama isteği doğal olarak artmaktadır. Bu sebeple son yıllarda hızla artan petrol, doğal gaz ve kömür gibi enerji kaynaklarındaki tüketim miktarı şimdi ve gelecekte enerji krizlerine sebep olacaktır. Aynı zamanda Dünya Kovid-19 salgını yaralarını sarmaya çalışırken, ortaya farklı enerji arayışları çıkartacaktır. Bu gelişme ile dünyadaki enerji krizi 2022 ve sonrasındaki yıllarda enerji arayışı kriz haline gelecektir. Bu nedenle yeni kaynak arayışı devam ederken mevcut kaynakları ekonomik, verimli, geri kazanımları maksimum seviyede ve enerji tüketimini tasarruflu şekilde kullanılmalıdır. Bu arayışlara en uygun süreçlerden biri kojenerasyon sistemleridir. Kojenerasyon veya Birleşik Isı ve Güç (CHP) sistemi aynı anda hem elektrik hem de kullanılabilir ısı üreten yüksek verimli bir sistemdir. Kojenerasyon sistemi yüksek enerji verimliliği, enerji tasarrufu sağlar ve sera gazı salınımını azaltır. Kojenerasyon sistemlerinin ana özelliği genel olarak, tek bir enerji kaynağı tüketimi süreci aracılığıyla elektrik ve faydalı ısı üretir. Kojenerasyon sistemi ile elektrik, tüketim noktasında üretilir. Bu durum arzın ulaşım ve dağıtım ile ilgili arızalara ve kayıplara maruz kalmaması anlamına gelmektedir. Aynı zamanda, dağıtım ve bakım maliyetleri ortadan kalkmaktadır. Kojenerasyon sistemlerinin kullanımının enerji tüketiminin azalmasına ve daha temiz yakıtların kullanımına imkan vermesi sonucunda çevreye daha az zarar verilmesi, kojenerasyon sistemlerinin yapılabilirliği açısından avantajlı sayılabilecek özelliklerdendir. Sayılan özellikler, literatürden alınan bilgiler, yapılan hesaplamalar ve araştırmaların ışığında yapılan bu test çalışmasının sonucunda da kojenerasyon uygulamasının avantajlı bir sistem olduğu kanıtlanmıştır. Sistemin analiz sonuçlarına göre üniversitenin yıllık amortisman sonucu 1.916.847,57 TL/Yıl yatırım için ilk maliyet yaklaşık 2,85 yıl gibi kısa bir zaman diliminde amorti edebilme durumu hesaplanmıştır.In this study, in order to use the energy efficiency of Aksaray University at a high level, the economic analysis of the cogeneration system was made according to the energy needs of the university. Increasing population in the world, technological advances and people's desire to live in modern conditions naturally increase. For this reason, the amount of consumption in energy resources such as oil, natural gas and coal, which has increased rapidly in recent years, will cause energy crises now and in the future. At the same time, while the world is trying to heal the wounds of the Covid-19 epidemic, different energy searches will emerge. With this development, the energy crisis in the world will become a crisis in 2022 and the following years. For this reason, while the search for new resources continues, existing resources should be used economically, efficiently, with maximum recovery and energy consumption saving. One of the most suitable processes for these pursuits is cogeneration systems. A Cogeneration or Combined Heat and Power (CHP) system is a highly efficient system that simultaneously produces both electricity and usable heat. The cogeneration system provides high energy efficiency, energy savings and reduces greenhouse gas emissions. The main feature of cogeneration systems is generally generating electricity and useful heat through a single process of energy source consumption. With the cogeneration system, electricity is produced at the point of consumption. This means that the supply is not subject to failures and losses associated with transportation and distribution. At the same time, distribution and maintenance costs are eliminated. Less damage to the environment as a result of the use of cogeneration systems to reduce energy consumption and to use cleaner fuels is one of the features that can be considered advantageous in terms of the feasibility of cogeneration systems. As a result of this test study, which was carried out in the light of the listed features, information obtained from the literature, calculations and researches, cogeneration application has proven to be an advantageous system. According to the analysis results of the system, it has been calculated that the university can amortize its investment cost in a short period of approximately 2.85 years as a result of annual depreciation
Protective effects of sinapic acid against lead acetate-induced nephrotoxicity: a multi-biomarker approach
No full textLead acetate (PbAc) is one of the top five most dangerous toxic heavy metals, particularly leading to kidney damage and posing serious health risks in both humans and animals. Sinapic acid (SNP) is a naturally occurring flavonoid found in fruits and vegetables that stands out with its antioxidant, anti-inflammatory, and anticancer properties. This is the first study to investigate the effects of SNP on oxidative stress, inflammation, apoptosis, autophagy and endoplasmic reticulum (ER) stress in PbAc-induced nephrotoxicity in rats by biochemical, molecular and histological methods. 35 Spraque dawley rats were randomly divided into five groups of 7 rats each: control, PbAc, SNP (10mg/kg), PbAc + SNP 5, PbAC + SNP 10. PbAc at a dose of 30 mg/kg body weight was administered via oral gavage alone or in combination with SNP (5 and 10 mg/kg body weight) via oral gavage for seven days. While PbAc impaired renal function by increasing serum urea and creatinine levels, SNP decreased these levels and contributed to the improvement in renal function. The administration of SNP reduced oxidative stress by increasing PbAc-induced decreased antioxidant enzyme (SOD, CAT, and GPx) activities and GSH levels, decreasing MDA levels, a marker of increased lipid peroxidation. SNP administration reduced NF-κB, TNF-α, IL-1β, NLRP3, and RAGE mRNA transcription levels, NF-κB, and TNF-α protein levels that are among the PbAc-induced increased inflammation parameters. Decreases in antiapoptotic Bcl-2 and increases in apoptotic Bax, APAF-1, and Caspase-3 due to PbAc exposure, SNP reversed the situation. SNP reduced ER stress caused by PbAc by increasing PERK, IRE1, ATF-6, CHOP, and GRP-78 levels and made it tend to regress. SNP reduced autophagy damage by decreasing the Beclin-1 protein level increased by PbAc. The findings of the present study suggested that SNP attenuates PbAc-induced nephrotoxicity
Environmental performance of accommodation establishments in the protected areas: case of Bolu, Türkiye
No full textProtected areas in tourism destinations are among the places where sensitivity should be exercised for the tourism sector. Accommodation establishments, particularly in protected areas, are considered in terms of environmental performance. This study aims to reveal the environmental performance levels of accommodation establishments in protected areas. The scale developed by Erdoğan and Tosun (2009) was used for the purpose of evaluating the environmental performance in accommodation establishments. Study data has been collected from business owners and executive directors in accommodation establishments located in protected areas in Bolu province of Türkiye. The data obtained in the study has been analyzed through the AMOS package program. The findings obtained from the study reveal that the environmental performance of accommodation establishments is not sufficient. The performance of the establishments to save energy by using the key card control system in the rooms is at low levels. In particular, the performance of the establishments regarding managerial knowledge on the environmental protection is required to be increased. It is thought that this study will contribute to the literature as it is one of the limited studies dealing with the environmental performance of accommodation establishments located in protected areas
Use of different food wastes as green biosorbent: isotherm, kinetic, and thermodynamic studies of Pb2+
No full textLead (Pb2+) can contaminate waters from many sources, especially industrial activities. This heavy metal is an amphoteric, toxic, endocrine-disrupting, bioaccumulative, and carcinogenic pollutant. One of the effective and economical processes used to remove lead from water is adsorption. The fact that the adsorbents used in this method are easily available and will contribute to waste minimization is the primary reason for preference. In this study, the adsorption abilities and surface properties of tea waste (TW), banana peels (BP), almond shells (AS), and eggshells (ES) which are easily available do not need modification and have very high (> 90%) removal efficiencies presented with isotherm, kinetic, and thermodynamic perspectives as detail. The surface structures and elemental distribution of raw adsorbents were revealed with SEM/EDX. Using FTIR analysis, carboxylic (–COOH) and hydroxyl groups (–OH) in the structure of TW, AS, BP, and ES were determined. It was determined that the Pb2+ adsorption kinetics conformed to the pseudo-quadratic model and its isotherm conformed to the Langmuir. The optimum adsorption of Pb2+ was ranked as BP > ES > AS > TW with 100, 68.6, 51.7, and 47.8 mg/g qm, respectively. The fact that the process has negative ΔG° and positive ΔH° values from a thermodynamic point of view indicates that it occurs spontaneously and endothermically. According to the experimental data, the possible adsorption mechanism for Pb2+ has occurred in the form of physisorption (van der Waals, electrostatic attraction) and cooperative adsorption including chemisorption (complexation, ion exchange) processes
‘I wouldn't wish her on my worst enemy’: Discursive representation of women managers in a collaborative hypertext dictionary in Turkey
No full textCurrently regarded as ‘new publicity’, collaborative hypertext dictionaries owe their popularity to the assumption that truth might have various perspectives rather than a single explanation. Evaluated within the scope of Web 2.0 to refer to participatory culture and social networking, these online dictionaries have a noteworthy role in constructing discourses of inclusion and/or exclusion. Informed by the theory of Discourse and Ideology, this article critically examines discourse representations of women managers in an online collaborative dictionary launched in Turkey, ‘Ekşi Sözlük’. Critical discourse analysis was applied to entries whose title included kadın yönetici (women managers) to identify discursive strategies deployed in the portrayal of women managers. The findings unveil traces of online misogyny that is systematically perpetuated via a pejorative and marginalizing language that overwhelms positive depictions. Emerging themes include the perception of the presence of women managers as a threat and of their inadequacy in management on the basis of traditional gender stereotypes
New Social Movements and Digital Activism
No full textThe use of digital has shifted to a different format, especially with the prominence of interaction with Web 2.0-based social networking sites that developed after internet technology. These environments, which provide users with a platform independent of time and space, have transformed daily and professional life practices, and public spaces have been replaced by virtual communities. Historically, social movements based on class struggle have also been affected by this change. Although the use of media tools in social movements dates back to the 18th century, individuals can easily reach people who think like themselves and organize quickly through social media. Although digital activism, which is one of the trends of digital technology prevailing in the 21st century, has been exposed to criticism such as clicktivism, it has also become an effective force in the political arenas. In this study, changing social movements on the axis of digital technologies will be discussed in general terms to digital activism
Performance of refrigerants employed in rooftop air-conditioners
No full textUnlike earlier studies, this study examines six refrigerants with various properties using the same rooftop air conditioning system of a building to evaluate performance. Performance metrics such as cooling capacity, energy consumption, temperature, and pressure were calculated. Laboratory testing of a rooftop air conditioner with R410a was performed to validate the simulation program's predicted data. Six distinct refrigerants' carbon emissions in two different scenarios were calculated using the Life Cycle Climate Performance technique, which was evaluated for environmental studies. These experimental tests were carried out at temperatures of 20 °C, 25 °C, 30 °C, and 35 °C, respectively. Maximum discrepancies between simulated and experimental results for cooling capacity, energy consumption, and energy efficiency were calculated to be 2.8%. The study found the lowest value in the R1234yf carbon emission at 51.30 kg CO2e. The highest cooling capacity was 154760.34 W in R454b, and the lowest cooling capacity was 76949.94 W in R1234yf. The highest EER value was 3,018 in R454b, while the lowest released was 2.257 in R22. The SEER value was 4.101 for R32 and 2.298 for R1234yf. The simulations concluded that R410a, R454b, and R32 refrigerants have superior cooling capacities
Honey De-crystallization by radio frequency heating for process efficiency: Computational monitoring combined with time domain nuclear magnetic resonance
No full textIndustrial de-crystallization of honey is carried out by using hot water or air at 60 °C or higher temperatures with the cost of energy and longer process times. The objectives of this study were to apply RF processing for de-crystallization and monitor this process with time-domain nuclear magnetic resonance (TD-NMR) data and a computational model. For this purpose, crystallized honey samples were processed in a 10 kW - 27.12 MHz free-running oscillator RF system, and experimental temperature data were used to validate the developed computational model. TD-NMR experiments were performed to monitor the de-crystallization, and the obtained kinetics data were coupled with temperature increase to compute the crystal content changes through the process. The RF de-crystallization led to a significant decrease (>70% compared to the conventional processes) in process time for industrial scale processing demonstrating its sustainability