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Use of Probiotics for Safe Quail Meat Production
No full textSafe meat production is an important aspect to avoid human health hazards. The use of probiotics in poultry is an important tool to produce safe meat among several established biotechnological approaches. In this experiment, we studied the effects of probiotics for producing safe Japanese quail meat. 150 Japanese quail chicks were reared for a period of six weeks using various doses of probiotics (0, 0.5, 1, 1.5, and 2g per litre of water). The chicks were randomly distributed into five treatment groups with three replications each. The number of birds in each replication was 10. After rearing six weeks, significantly high body weight was found at probiotic concentrations of 1, 1.5, and 2g per litre of water. The feed intake in various treatments did not differ significantly, but comparatively better feed conversion ratios were observed at probiotic treatments. Water quality was not significantly differed as a result of addition of probiotics to the water. The reason for this better growth performance is probably due to the multiple benefits of probiotics in poultry. Probiotics could have maintained gut health with better nutrient utilization and availability that might have been led to higher body weight gain in the quail. In future experiments, challenging the birds with diseases or comparing probiotics with antibiotic growth promoters is required to ensure the efficiency of probiotics
Comparative analysis of Multiple linear Regression (MLR) and Adaptive Network-Based fuzzy Inference Systems (ANFIS) methods for vibration prediction of a diesel engine containing NH3 additive
No full textWith the increase in population, the need for fuel has led researchers to search for alternative green fuels. The leading of these alternatives is Ammonia (NH3), which minimizes carbon emission as opposed to petroleum derivatives that contain carbon, primarily when used as fuel. In this study, NH3 was mixed with sunflower biodiesel in different volumetric ratios and burned at varying engine speeds using a diesel engine, recording experimental vibration data in the engine block. With these obtained data, Multiple Linear Regression (MLR) and Adaptive-Network Based Fuzzy Inference Systems (ANFIS) methods were used to compare the two methods by examining the effect of inputs on output and the factors affecting output. In this context, a total of 5 variables, namely NH3 additive rate, x-axis (m/s2), y-axis (m/s2), RMS (m/s2), and Engine Speed (m/s), were used as inputs in both models and the dependent variable z-axis (m/s2) was estimated. For this purpose, first of all, estimation was carried out with MLR method, then different models were created with ANFIS method, and the prediction performances of both methods were calculated. In the performance evaluation of the test data, R2 (certainty coefficient) value for MLR was found as 0.58, Mean Squared Error (MSE) was 10.61, Mean Absolute Error (MAE) was 2.43, and Root Mean Squared Error (RMSE) was 3.25, while R2 value for ANFIS was calculated as 0.86, MSE 3.85, MAE 1.25 and RMSE 1.96. When both methods are compared in terms of performance, it is seen that ANFIS gives better results than MLR
A Test of the Socioemotional Selectivity Theory Among Young Adults
No full textThe primary assertion of the Socioemotional Selectivity Theory (SST) is that with increasing age, individuals become more selective in their social networks and consciously reduce their social network size. Although SST has received considerable support from studies conducted in mostly individualistic countries, such as the United States and Germany, there are very few studies in which it has been tested in collectivistic countries. Therefore, the present study aimed to test the SST argument in Turkey. There were 219 Turkish young adult participants, aged 18–28 (Mage = 20.07 years, SD = 1.76). Participants completed a Social Convoy Questionnaire, Future Time Perspective (FTP) scale and Positive and Negative Affect Schedule. Via the structural equation model, it was found that (a) open-ended FTP directly and positively related to positive affect, higher level of social satisfaction, and smaller social network sizes; and (b) social satisfaction mediated the relationship between FTP and young adults’ positive affect. The results confirm the SST’s arguments and highlight the importance of social satisfaction in helping shape young adults’ positive affect
Türkiye'deki bilgi teknoloji firmalarının entellektüel sermayesinin incelenmesi
No full textLisansüstü Eğitim Enstitüsü, Yönetim Bilişim Sistemleri Ana Bilim DalıBu tezin amacı Borsa İstanbul'a kote olmuş bilgi teknolojileri ve telekomünikasyon firmalarının 2002 ile 2021 yılları arasındaki entellektüel sermaye katsayısını incelemek ve Covid-19 döneminde bu katsayının nasıl bir seyir izlediğini araştırmaktır. Piyasa Değeri/Defter Değeri (PD/DD) ve Tobin Q rasyosu vasıtasıyla entellektüel sermaye katsayısı bu firmalar için hesaplanmıştır. Elde edilen sonuçlar bu firmalar için entellektüel sermaye katsayısının pandemi dönemi öncesinde genellikle düşük olduğunu gösterirken pandemi sırasında bu katsayının daha da azaldığını göstermektedir. Bu çalışmada ele alınan firmalar için entellektüel sermaye değerinin oldukça heterojen olduğu da görülmektedir. Bu tezin ilgili literatüre bilgi teknolojileri ve telekomünikasyon firmalarının entellektüel sermayesinin saptanması noktasında katkı sağlaması beklenmektedir. Aynı zamanda pandemi döneminin bu firmaların entellektüel sermayesine etkisi çerçevesinde de ilgili literatüre katkı sağlaması beklenmektedir.The aim of this thesis is to study the coefficient of intellectual capital of the information technology and telecommunication firms listed on Borsa Istanbul between 2002 and 2021 and to explore how this coefficient has evolved during the Covid-19 period. The coefficient of intellectual capital is calculated for these firms using the market-to-book ratio (MV /BV) and Tobin's Q ratio. The results show that the coefficient of intellectual capital for these companies is generally low before the pandemic, while this coefficient continues to decrease during the pandemic. It can also be observed that the value of intellectual capital is quite heterogeneous for the firms considered in this study. This thesis is expected to contribute to the related literature in determining the intellectual capital of information technology and telecommunications firms. It is also expected to contribute to the literature on the impact of the pandemic period on the intellectual capital of these firms
BİNGÖL BAĞLARPINARI (TEMRAN) KÖYÜ MİRLİVA MUHAMMED BEY CAMİİ VE HAZİRESİ’NİN KORUMA SORUNLARI VE RESTORASYON ÖNERİLERİ
No full textGeçmiş toplumların kültürel, sosyal ve ekonomik özelliklerini günümüze yansıtan, başka bir ifadeyle bizden önceki toplulukların yaşam pratikleri hakkında bilgiler sunan en önemli kaynakların başında somut kültür varlıkları gelmektedir. Nesiller arası bilgi aktarımının sürdürülebilir olması kültür varlıklarının doğru bir şekilde korunması ve gelecek kuşaklara aktarılması ile mümkündür. Bu çalışmada, daha öncesinde herhangi bir nitelikli koruma çalışmasına konu olmamış Mirliva Muhammed Bey Camii ve Haziresi ele alınmıştır. Altı bölümden oluşan çalışmada öncelikle, ele alınan yapının ve bulunduğu yerin tarihi hakkında genel bilgiler verilmiştir. Caminin ve haziresindeki mezar taşlarının mimari ve sanatsal özellikleri açıklanmış ve mevcut koruma sorunları ifade edilmiştir. Ayrıca, yapıların güncel koruma sorunları mimari çizimlerle ve fotoğraflarla belgelenmiştir. Tespit edilen koruma sorunlarının ortadan kaldırılması ve yapının özgün niteliklerini yitirmeden korunması amacıyla çeşitli koruma önerileri sunulmuştur. Bu çalışmanın, Mirliva Muhammed Bey Camii’nin ve haziresindeki özgün mezar taşlarının korunması ve gelecek kuşaklara aktarılması adına farkındalık yaratması ve yapılacak çalışmalara katkı sunması umulmaktadır
Evaluation of drug carrier hepatotoxicity using primary cell culture models
No full textThis study aims to establish a primary rat hepatocyte culture model to evaluate dose-dependent hepatotoxic effects of drug carriers (lipopolymer nanoparticles; LPNs) temporal. Primary rat hepatocyte cell cultures were used to determine half-maximal Inhibition Concen-trations (IC50) of the drug-carrier library. Drug-carrier library, at concentrations <50 mu g/mL, is benign to primary rat hepatocytes as determined using albumin and urea secretions. Albumin, as a hepatic biomarker, exhibited a more sensitive and faster outcome, compared to urea, for the determination of the IC50 value of LPNs. Temporal measurements of hepatic biomarkers including urea and albumin, and rigorous physi-cochemical (hydrodynamic diameter, surface charge, etc.) characterization, should be combined to evaluate the hepatotoxicity of drug carrier libraries in screens.(c) 2023 Published by Elsevier Inc.National Institutes of Health [NIH 1R21GM136002]; NIH [R41 TR003247]; National Science Foundation (NSF Engineering Research Center) [1941543]; Massachusetts General Hospital (MGH) Executive Committee on Research (ECOR); Turkish Fulbright Commission; Fulbright Postdoctoral Scholarship; Scientific and Technological Research Council of Turkey (Tubitak); [1059B191801017]This research was supported by grants from the National Institutes of Health (NIH 1R21GM136002 and NIH 5R01HL145031) , the National Science Foundation (NSF Engineering Research Center, Award #1941543) , and a Massachusetts General Hospital (MGH) Executive Committee on Research (ECOR) Interim Support Fund at Dr. Usta's lab. We also acknowledge the support and use of facilities at the Morphology and Imaging Shared Facility, and Regenerative Medicine Shared Facility provided at the Shriners'Children-Boston. We also acknowledge the Turkish Fulbright Commission for a Fulbright Postdoctoral Scholarship and the Scientific and Technological Research Council of Turkey (Tubitak 2219 Award #1059B191801017) for Dr. Gunes Kibar. We are also grateful to the NIH (Grant R41 TR003247 to Synergyan, LLC and KR) for partially supporting this study at Dr. Rege's lab. The content of this article is solely the responsibility of the authors and does not necessarily represent the official views of the NIH or the NSF
Epidemic Spread Analysis in Social Communication Networks With Sir Model
No full textCompartmental mathematical models are frequently used in epidemiology. These models are based on certain assumptions to mathematically model real-life events. However, these assumptions have some limitations. One of these limitations is that they assume that the community is homogeneous, although communities are often heterogeneous. For example, a community may have people or super-spreaders who are not in contact with anyone infected with the virus. In case of limited opportunities, the rate of disease spread can be reduced by vaccinating super-spreaders instead of normal individuals. In the study, centrality values of each individual in the community are determined using a real data set. Vaccinated (immune) and infected individuals are then selected according to certain criteria, and disease spread is simulated. Finally, results are produced using the SIR model, which is the basis of compartmental models. According to the results obtained, the minimum amount of vaccine required to prevent disease spread is calculated. As a result, it was concluded that using the recommended method instead of traditional methods to prevent the spread of disease in the community will result in a 14.39% reduction in vaccine usage
Two-way coupled aerodynamics and vehicle dynamics simulations of a heavy ground vehicle subjected to crosswind of various frequencies
No full textThe present study investigates the dynamic characteristics of a heavy ground vehicle subjected to crosswind with various frequencies using two-way coupled simulations between aerodynamics and vehicle dynamics, including the driver's steering inputs. Four different reduced frequencies of crosswind, which are equal to 4.2, 2.1, 1.3 and 0.9, are used. The results show that the absolute maximum magnitudes of the vehicle's lateral dynamic and aerodynamic characteristics increase inversely proportional with the reduced frequencies of crosswinds without the driver's steering input. However, when the driver's steering input is included in the vehicle's response to the crosswind disturbances, the vehicle's lateral dynamic characteristics increase by the largest amount for reduced frequencies of 1.3 and 2.1. Furthermore, for a reduced frequency of 0.9, the driver's steering inputs attenuate the unfavourable amplifications in the vehicle's lateral dynamic characteristics. In the present study, the reasons for the increase in the vehicle's lateral dynamic characteristics in the cases of reduced frequencies equal or greater than 1.3 with the driver's steering input are explained. Additionally, the results show that the vehicle is not controlled within the 0.5 m lateral margins of the road when the steering starts with a time delay of 1.0 s for reduced frequencies equal to or lower than 2.1.Swedish Innovation Agency Vinnova [2017-03391]; Centre for ECO2 Vehicle Design at KTH (Vinnova) [2016-05195]; Vinnova [2017-03391] Funding Source: Vinnova; Swedish Research Council [2016-05195] Funding Source: Swedish Research CouncilThe author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The author would like to gratefully acknowledge the co-funding he has received for this work from the Swedish Innovation Agency Vinnova (grant number 2017-03391) and the Centre for ECO2 Vehicle Design at KTH (itself funded by Vinnova grant number 2016-05195)
Elektrikli araçlar için tümü GaN tabanlı çok cihazlı serpiştirilmiş yükseltici dönüştücü yapısı
No full textLisansüstü Eğitim Enstitüsü, Elektrik ve Elektronik Mühendisliği Ana Bilim DalıSera gazı emisyonlarının azaltılması, küresel ulaşımda fosil yakıtların kullanımını azaltmak için sürekli bir yaklaşım gerektirir. Çevre dostu olmaları, verimlilikleri, sessizlikleri ve uzun vadeli sürdürülebilirlik potansiyelleri nedeniyle elektrikli araçlar, içten yanmalı motorlarla çalışan araçlara uygun bir alternatiftir. Elektrikli araçların artan popülaritesine rağmen, geleneksel araçlarla başarılı bir şekilde rekabet edebilmek için maliyet, kapasite, sürüş menzili, enerji kayıpları ve güç aktarma teknolojileri gibi alanlarda hala önemli ilerlemelere ihtiyaçları var. Bu nedenle, mimari ve verimlilik açısından güç iletimindeki ilerlemeler, on yıllardır bilim camiasının ön planında yer almaktadır. Doğru akımdan doğru akıma (DC'den DC'ye) dönüştürücüler, güç tüketimini azaltmak için optimize edilebilen, böylece enerji verimliliğini artıran, boyutları azaltılabilen ve böylece kompaktlık sağlayan devre bileşenlerine bir örnektir. Uygun bileşen seçimi ile birlikte devre sisteminin minyatürleştirilmesi ve hafif yapısal malzemelerin kullanımı, daha ucuz, daha duyarlı ve gelişmiş güvenilirliğe sahip sistemlerle sonuçlanabilir. İndüktör ve kapasitör gibi pasif bileşenler, sırasıyla giriş akımı ve çıkış voltajı dalgalanmalarını düzeltmeyi amaçlayarak dönüştürücü topolojilerinde çok önemli bir rol oynamaktadır. Ancak o kadar büyüktürler ki dönüştürücü için ayrılan alanın çoğunu kaplamaktadırlar. Bu nedenle, kullanılan pasif bileşenlerin sayısını ve minyatürleştirilmesini azaltmaya yönelik her türlü çaba, dönüştürücü teknolojisi için önemli bir ilerlemeyi temsil etmektedir. Galyum nitrür (GaN) ve silisyum karbür (SiC), son teknoloji verimli güç dönüştürücü cihazları tasarlamak için uygun olan geniş bant aralıklı yarı iletken malzemelerin iki örneğidir. Bu yarı iletkenlerin geniş bant aralığı, yüksek kritik parçalanma elektrik alanı, daha yüksek elektron hızı ve yüksek termal iletkenlik gibi özellikleri, pasif bileşenlerin boyutunda önemli ölçüde azalmaya, soğutucunun küçülmesine ve dönüştürücünün güç yoğunluğunun artmasına olanak tanır. Bu tezde, 2010 Toyota Prius Si-IGBT tabanlı yükseltici dönüştürücü topolojisi araştırılmış ve PSpice simülasyon yazılımı yardımıyla simüle edilmiştir. Bundan sonra, bu dönüştürücü yapısı, sırasıyla SiC ve GaN yarı iletkenlerini uygulanmasıyla çok cihazlı serpiştirmeli yükseltici dönüştürücü (MDIBC) topolojisi ile yeniden yapılandırıldı. SiC tabanlı ve GaN tabanlı MDIBC topolojilerinin performansını güç kaybı, verimlilik, pasif bileşenlerin boyutu ve ayrıca akım ve voltaj dalgalanmaları açısından analiz etmek için değişen anahtarlama frekanslarında iki önemli vaka çalışması kullanıldı. Her iki durumda da önemli ölçüde azaltılmış akım ve gerilim dalgalanmalarına rağmen pasif bileşenlerin daha düşük değerlerine ulaşılmıştır. GaN tabanlı MDIBC ile tüm anahtarlama frekanslarında elde edilen daha yüksek verimlilik sonuçlarının aksine, SiC tabanlı MDIBC, referans dönüştürücüye kıyasla 80 ve 100 kHz'de daha düşük değerlerle sonuçlandı. Önerilen GaN tabanlı MDIBC, ilk durumda akım için dalgalanmayı %93,4 ve voltaj için %40, ikinci durumda 100 kHz anahtarlama frekansında indüktör değeri için %88,5 ve kondansatör değeri için %97,92 azaltarak kıyaslama dönüştürüşünden daha yüksek verim elde edildi. Anahtar Kelimeler: akım ve voltaj dalgalanmaları, çok cihazlı serpiştirmeli yükseltici dönüştürücü (MDIBC), hibrit elektrikli araçlar, SiC ve GaN yarı iletkenler, verimlilikGreenhouse gas emissions reduction requires an ongoing approach to decreasing the use of fossil fuels in global transportation. Due to their environmental friendliness, efficiency, quietness, and potential for long-term sustainability, electric vehicles (EVs) are a viable alternative to those powered by internal combustion engines (ICE). Despite the rising popularity of EVs, they still need significant advancements in areas such as cost, capacity, driving range, energy losses, and powertrain technologies in order to successfully compete with conventional vehicles. Therefore, advancements in power transmission in terms of architecture and effectiveness have been in the foreground of the scientific community for decades. Direct current to direct current (DC/DC) converters are one example of circuit components that can be optimized to reduce power consumption, thereby enhancing energy efficiency, decreasing size, and thus providing compactness. Miniaturization of circuitry, together with proper component selection and the use of lightweight structural materials, might result in cheaper, more responsive systems with improved reliability. Passive components such as inductors and capacitors play a crucial role in converter topologies that aim to smooth out input current and output voltage ripples, respectively. However, they are so large that they occupy the majority of the space reserved for the converter. Therefore, any effort to reduce the number of passive components used and their miniaturization represents a significant advancement for converter technology. Gallium nitride (GaN) and silicon carbide (SiC) are two examples of wide band gap semiconductor materials that are suited for designing state-of-the-art efficient power converter devices. These semiconductors' features, such as their large bandgap, high critical breakdown electric field, high thermal conductivity and higher electron velocity allow a considerable reduction in the size of passive components, shrinking the heatsink and an increase in the converter's power density. In this thesis, the 2010 Toyota Prius Si-IGBT-based boost converter topology was investigated and simulated with the help of PSpice simulation software. After that, this converter structure was reconstructed with a multidevice interleaved boost converter (MDIBC) topology with implementing SiC and GaN semiconductors, respectively. Two prominent case studies with varying switching frequencies were utilized to analyze the performance of the SiC-based and GaN-based MDIBC topologies in terms of power loss, efficiency, the size of the passive components, as well as the current and voltage ripples. In both cases, it was achieved lower values of the passive components despite the relatively reduced current and voltage ripples. In contrast to the higher efficiency results achieved with GaN-based MDIBC at all switching frequencies, SiC-based MDIBC resulted in lower values at 80 and 100 kHz compared to the benchmark converter. Proposed GaN-based MDIBC achieved higher efficiency than the benchmark converter by lowering ripple by 93.4% for current and 40% for voltage in the first case, and by 88.5% for inductor value and 97.92% for capacitor value at 100 kHz switching frequency in the second case. Keywords: current and voltage ripples, efficiency, hybrid electric vehicles, multidevice interleaved boost converter, SiC and GaN semiconductor
Formulation and Processing Strategies to Reduce Acrylamide in Thermally Processed Cereal-Based Foods
No full textAcrylamide, a thermal process contaminant, is generated in carbohydrate-rich foods processed at high temperatures (above 120 °C). Since acrylamide indicates a human health concern, the acrylamide contents of various foods and the dietary exposure of the population to acrylamide are very well investigated. Commonly consumed foods in the daily diet of individuals such as bakery products, potato products and coffee are major dietary sources of acrylamide. In recent years, dietary exposure levels of the population and mitigation measures for reducing acrylamide in different food products have gained importance to decrease the public’s exposure to acrylamide. Since the complete elimination of acrylamide in foods is not possible, various mitigation measures to reduce acrylamide to levels as low as reasonably achievable have been developed and applied in the food industry. Mitigation strategies should be applied according to the different product categories during agricultural production, formulation, processing and final consumer preparation stages. The aim of this review is to evaluate formulation and processing strategies to reduce acrylamide in various cereal-based food products and to discuss the applicability of mitigation measures in the food industry by taking into consideration the organoleptic properties, nutritional value, cost and regulations in the light of current knowledge. © 2023 by the author