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Pathology of experimental arsenic toxicity in rats and investigation of protective effect of simultaneously administered Cistus laurifolius L. (Cistaceae)
No full textSodium arsenite is abundantly available in the environment, and arsenic toxicity is a public health problem that raises concerns worldwide. In this study, the protective effect of Cistus laurifolius L. (Cistaceae) against sodium arsenite-induced oxidative stress in rats was investigated. The 108 male Sprague-Dawley rats were divided into 12 equal groups. Group 1 was the negative control, and no treatment was given to the rats in this group. Group 2 was the normal control, and only carboxymethyl cellulose (CMC) was given as the solvent of the plant extract. Group 3 received 5 mg/kg sodium arsenite. Groups 4, 5, 6, and 7 were given 500 mg/kg/day doses of n-hexane, diethyl ether, ethyl acetate, and methanolic extracts of Cistus laurifolius L. (Cistaceae), respectively. Groups 8, 9, 10, and 11 were given a 500 mg/kg/day doses of sodium arsenite (5 mg/kg) and respectively the n-hexane, diethyl ether, ethyl acetate, and methanolic extracts of Cistus laurifolius L. simultaneously. Group 12 was given sodium arsenite (5 mg/kg), as well as alpha lipoic acid (70 mg/kg) as a standard control. All treatments were given for 32 days through gastric gavage. Cistus laurifolius extracts and alpha-lipoic acid reduced oxidative stress and protected tissues from histopathological damage, while ethyl acetate extract showed a greater reduction in metallothionein positivity. In conclusion, it was determined that Cistus laurifolius L. extracts, especially its ethyl acetate extract, had protective effects against sodium arsenite-induced oxidative damage in rats.Scientific Research Council of Afyon Kocatepe University [10.VF.19]The authors thank the Scientific Research Council of Afyon Kocatepe University (10.VF.19) for funding this study. This work was developed as part of a PhD thesis in Pathology at the Faculty of Veterinary Medicine, Afyon Kocatepe University (Turkey)
Assessment of mutagenicity of Pyridaben by Ames Salmonella/microsome method
No full textBu çalışmanın tarım alanında akarisit ve insektisit olarak
kullanılan ve pyridaben (Pyridaben 20%WP) aktif maddesinin
Ames/Salmonella mikrozom testi ile mutajenitesinin
değerlendirilmesi olup çalışma S9 fraksiyon varlığı ve
yokluğunda olmak üzere iki aşamalı olarak planlanmıştır.
Deneyde Salmonella typhimurium’a ait en yaygın çalışılan iki
suş olan TA100 ve TA98 mutant suşları kullanılmış olup
uygulama öncesinde test maddelerinin sitotoksik dozları
belirlenmiş ve deney için sitotoksik olmayan 5 farklı doz
uygulaması yapılmıştır. Mutajenik aktiviteyi belirlemek
amacıyla pyridaben’in 800, 400, 200, 100, 50 ve 25 μg/plak
dozları çalışılmış olup bulgular Dunnett-t testi kullanılarak
istatistiksel açıdan değerlendirilmiş ve veriler negatif kontrol
değerleri ile kıyaslanarak değerlendirme yapılmıştır. Test
bulgularına göre; pyridaben’in yalnızca 800 μg/plak dozunun
hem S9 fraksiyonu varlığında hem de aynı dozun S9 fraksiyonu
yokluğunda her iki suşta da mutajenik aktivite gösterdiği tespit
edilmiştir.This study is to evaluate the mutagenicity of pyridaben
(Pyridaben 20%WP), which is used as an insecticide and
acaricide in agriculture, by Ames/Salmonella microsome test
and the study was planned in two stages as in the presence
and absence of S9 fraction. In the study, the two most widely
studied strains of Salmonella typhimurium, TA98 and TA100
mutant strains, were used and the cytotoxic doses of the test
substances were determined before the application and 5
different non-cytotoxic doses were applied for the experiment.
In order to determine the mutagenic activity, pyridaben doses
of 800, 400, 200, 100, 50 and 25 μg/plate were applied and the
data were evaluated statistically using Dunnett’s-t test and the
data were compared with the negative control values.
According to the test findings; it was determined that only 800
μg/plate dose of pyridaben showed mutagenic activity in both
strains both in the presence of S9 fraction and in the absence
of S9 fraction at the same dose
Effects of combined alkalinity and ultrasonication on element release and structural alteration in EAF slag
Get PDFThis study investigated electric arc furnace (EAF) slag dissolution in varying NaOH solutions (10 M, 0.1 M, and 0.01 M) and assessed the impact of ultrasonication on enhancing element release. After conducting dissolution tests based on 1/100 g/mL as the solid-to-liquid ratio, ICP-OES analysis was used in determining the dissolved elemental concentrations, while XRD, FTIR, BET, and XPS measurements facilitated understanding of the alterations in the structure and surface. According to the findings, Al, Si, Ca, and Fe elements dissolved in different concentrations, depending on the alkalinity level and technique applied. Higher alkalinity led to more Al and Si species dissolving, reaching up to 12 % dissolution. In contrast, moderate and slight alkalinity reduced the extent of dissolution (< 5 %) for Al and Si or even caused the disappearance of some species. Additionally, the results showed that ultrasonication provided more element releases, with up to 50 % enhancement, compared with stirring. XRD patterns revealed that the EAF slag had an intricate crystal structure including more than 15 phases. Use of 10 M NaOH solution resulted in a considerable breakdown of the EAF slag structure and the formation of new phases, whereas the change in structure was less prominent in 0.1 M and 0.01 M NaOH conditions. In another aspect, BET analysis showed that both alkalinity and ultrasonication increased the particle surface area. In conclusion, this study revealed that EAF slag released different elements with various concentrations and NaOH molarities, and ultrasonication was able to enhance the dissolution process to a certain degree.Scientific and Technological Research Council of Turkiye (TUBITAK); Research Council of Finland [354263]; Jane ja Aatos Erkko Foundation; Tiina ja Antti Herlin Foundation; Centre for Material Analysis, University of Oulu, FinlandRecep Kurtulus wishes to acknowledge The Scientific and Technological Research Council of Turkiye (TUBITAK) , Science Fellowships and Grant Programme Directorate, for the grant within the scope of the 2219 program. Additionally, this work was supported by the Research Council of Finland (#354263) and AS4G project funded by the Jane ja Aatos Erkko and Tiina ja Antti Herlin Foundations. Part of the work was carried out with the support of the Centre for Material Analysis, University of Oulu, Finland. Mr. Jani Osterlund, Mr. Jarno Karvonen, and Mrs. Elisa Wirkkala are acknowledged for their help in the laboratory work
Dönüşen Dinamikler Bağlamında Aile ve Sosyal Hizmetler Bakanlığı
No full textBu çalışma değişen şartlar ve dönüşen dinamikler bağlamında Aile ve Sosyal Hizmetler Bakanlığı’nın teşkilatlanmasını ve ürettiği politikaları incelemeyi amaçlamaktadır. Aile, en temel toplumsal kurum olduğu gibi milletlerin kendi benlik ve kimliklerinin gelecek nesillere aktarılmasında rol alan en temel aktördür. Teknolojik gelişmeler, ekonomik dalgalanmalar, göç gibi dinamikler bireysel yaşamları, aile kurumunu ve devleti derinden etkilemektedir. Makale, Aile ve Sosyal Hizmetler Bakanlığı’nın yapılanmasını ve sunduğu hizmetleri, günümüzün değişen dinamikleri bağlamında ele alması açısından önem taşımaktadır. Yöntem olarak Bakanlığın oluşumu, görev ve yetkileri tarihsel bağlam içerisinde incelenmiş; ailenin karşılaştığı demografik dönüşüm, yoksulluk, dijitalleşme, aile yapısının değişmesi gibi risklere karşı Bakanlığın yapısı ve sunduğu hizmetlerin etkinliği değerlendirilmiştir. Bakanlık, ailenin korunması ve güçlendirilmesi vizyonu çerçevesinde yenilikçi sosyal politikalar üretmeye; planladığı faaliyetler ve projeleri kamu kurum ve kuruluşları, sivil toplum örgütleri, belediyeler, üniversiteler, özel sektör ile işbirliği içerisinde hayata geçirmeye çalışmaktadır. Bu doğrultuda Bakanlık; birey, aile ve toplumsal değerleri koruyarak toplumun her ferdine ulaşmayı hedefleyen bütüncül bir politika benimsemektedir. Makalede, Aile ve Sosyal Hizmetler Bakanlığı’nın, sunduğu hizmetleri ve yürüttüğü politikaları daha kapsamlı, standart ve etkin hale getirebilmek için dönüşen dinamiklere uyum sağlamaya çalıştığı sonucuna varılmıştır
Optimization of solar and geothermal energy assisted power, heating and hydrogen production using field programmable gate arrays and artificial neural networks
No full textThis study presents a thermodynamic and economic evaluation of an integrated solar-geothermal energy system designed to produce electricity, hydrogen, and space heating. The motivation of the work is to improve the efficiency and cost-effectiveness of renewable hybrid systems by applying advanced digital optimization. The methodology employs a multilayer artificial neural network implemented on a field programmable gate array, enabling real-time optimization with high computational precision. The novelty of this research lies in the unique combination of solar and geothermal resources with neural network-based hardware optimization, which allows simultaneous production of multiple energy outputs with improved performance. Classical analysis yielded a cycle power output of 1113 kW, heating capacity of 7351 kW, energy efficiency of 32.87 %, exergy efficiency of 34.31 %, electricity cost of 0.09373 /kg. With the proposed optimization, the system achieved 1913 kW of power, 1340 kW of fuel cell output, 8936 kW of heating capacity, 34.04 % energy efficiency, and 43.66 % exergy efficiency, while reducing the hydrogen cost to 1.707 /kWh, and the electricity cost to 0.08417 $/kWh. These results demonstrate that combining renewable energy with advanced real-time optimization can significantly enhance sustainable energy systems' technical performance and economic viability
M/LSTM-GRU HYBRID MODEL FOR SOLAR RADIATION ESTIMATION
No full textSolar energy is acknowledged as an environmentally friendly and clean renewable energy source, making it a crucial research topic. Estimation of the future radiation levels before and during the use of this source is vital for proper planning and operation of a photovoltaic (PV) system. In this study, a solar energy forecasting method was developed, utilizing both Long Short-Term Memory and Gated Recurrent Units models. The performance of the developed method was tested using various metrics on real-time, multivariate solar radiation data from a specific region in Turkey. Examining the results reveals lower RMSE, MSE, MAE performance values and higher R2 values compared to many similar studies in the literature. This indicates the success of the proposed model, positioning it as a viable alternative
Influence of conductive nanofillers on the mechanical and self-sensing properties of bis(2-ethylhexyl) succinate biopolymer cement composites
No full textThe utilization of cementitious sensors designed with biopolymers that have been modified with nanomaterials holds great potential for the development of smart structures, as this approach aligns with principles of sustainability and environmental responsibility. The present study constitutes a thorough analytical investigation of the piezoresistive characteristics of Bis(2-ethylhexyl) succinate (BES) modified with conductive nanofillers, including graphene nanoplatelets (GNP) and silver nanoparticles (AgNPs). Furthermore, the manner in which these properties correspond to their microstructural attributes is elucidated in this analysis. It has been determined that conductive nanofillers exhibit the highest stress sensitivity when the threshold value for GNP and AgNPs is set to 0.25 mg/ml for BES cement composites. In addition, it has been established that composite materials manifest an optimum stress sensitivity of -0.98 %/MPa and 10.86 %/MPa when subjected to compressive and flexural stress, respectively. The molecular interaction between the well-dispersed and distributed nanomaterials and the gelled BES and hydrated products resulted in a qualitatively remarkable piezoresistive behavior performance. The interaction was facilitated by the following processes: the filling of voids with nanofiller, an increase in deformability under bending by BES, and the convergence of nanomaterials due to hydrogen bonds under compression
SOME PROPERTIES OF ROUGH CONVERGENCE OF DOUBLE SEQUENCES IN 2-NORMED SPACES
Get PDFIn this study, firstly, we investigated relationships between rough convergence and classical convergence of double sequences in 2-normed space. Also, we studied some properties of the rough convergence, the set of rough limit points and rough cluster points of a double sequence in 2-normed space. Also, we examined the dependence of r-limit points set LIM (R)(2)x(mn) of a fixed double sequence (x(mn)) on varying parameter r in 2-normed space
Doğal Birlikten Ahlaki Kuruma: Rousseau ve Hegel’de Aile Kavramı
Get PDFBu çalışmada ele alacağımız Jean-Jacques Rousseau ve Georg Wilhelm Friedrich Hegel, modern felsefe tarihinde aileye dair derinlikli ama birbirinden farklı yaklaşımlar geliştirmiş iki önemli düşünürdür. Her iki filozof da aileyi birey ile toplum arasındaki aracı bir kurum olarak görür. Ancak ailenin işlevi, doğası ve sınırları konusundaki yaklaşımları hem ontolojik hem normatif düzeyde ciddi farklılıklar taşır. Rousseau’nun siyaset felsefesi, birey ile toplum arasındaki ilişkiyi özgürlük, erdem ve eğitim eksenlerinde ele alır. Bu çerçevede Ekonomi Politik’te aile kavramı hem siyasal otoritenin doğasını anlamak hem de yurttaşın oluşum sürecini kavramak açısından kilit bir öneme sahiptir. Rousseau'nun aileye dair düşünceleri, Toplum Sözleşmesi ve Emile gibi sonraki eserlerinde daha sistemli biçimde işlenir ve aile, bireyin toplumsal yaşamla olan bağının kurucu unsuru olarak ön plana çıkar. Hegel ise Hukuk Felsefesinin Prensipleri adlı eserinde aileyi, “etik yaşam”ın (Sittlichkeit) üç temel aşamasından ilki olarak tanımlar. Aile, bireyin soyut öznel özgürlükten somut evrensel özgürlüğe geçiş yaptığı sürecin ilk adımıdır. Sevgi ile görev duygusunun birleşimi olarak kurulan ailede birey, kendini başkasıyla olan birliğinde gerçekleştirir. Bu yönüyle aile, özgürlüğün ilk somut biçimi ve devletin etik yapısının ön koşuludur. Bu çalışmanın amacı, Rousseau ve Hegel’in aile anlayışlarını karşılaştırmalı olarak inceleyerek, doğal birlikten etik bir kuruma dönüşen aile kavrayışının nasıl şekillendiğini ortaya koymaktır
A novel boustrophedon-based coverage algorithm for industrial cleaning robots: performance improvements and implementation
No full textEndüstriyel temizlik robotları, geniş ve karmaşık ortamlarda, özellikle fabrikalar ve büyük perakende alanlarında kullanılmaktadır. Bu robotların, engellere çarpmadan veya çok yaklaşmadan etkili bir şekilde çalışması kritik öneme sahiptir. Boustrophedon kapsama alanı temelli tam kapsama yol planlama algoritması, robotların bir alanı eksiksiz ve düzenli bir şekilde taramasını sağladığı için endüstriyel uygulamalarda sıkça tercih edilmektedir. Bu çalışmada, Robot Operating System (ROS) platformunda özelleştirilmiş bir boustrophedon kapsama alanı temelli yol planlama algoritması sunulmaktadır. Önerilen algoritma, klasik boustrophedon algoritmasına kıyasla güvenlik marjı yerine parametrik şişirme yarıçapı kullanarak robotun hareket alanını optimize etmektedir. Bu yöntem, robotun engellere yaklaşmadan alanı daha verimli kapsamasını sağlamaktadır. Gerçekleştirilen testlerde, önerilen algoritma, klasik boustrophedon algoritmasına kıyasla %98,2 kapsama yüzdesine ulaşarak daha yüksek bir kapsama sağlarken, dönüş sayısını %61 oranında azaltmıştır. Seyahat süresi ve yol uzunluğu gibi performans metriklerinde de kayda değer iyileştirmeler gözlemlenmiştir. Testlerde hesaplama süresi 44 saniye, yol takip süresi ise 101 saniye olarak ölçülmüştür. Robotun toplamda kat ettiği mesafe 19,43 metre olup, dönüş miktarı ise 19,56 radyan olarak belirlenmiştir. Bu sonuçlar, önerilen algoritmanın hem engelli hem de engelsiz ortamlarda daha kısa sürede daha yüksek kapsama oranıyla çalışabileceğini göstermektedir. Algoritma, endüstriyel temizlik robotları için önemli bir gelişme sunmakta ve geniş çaplı uygulamalarda etkin bir çözüm olarak öne çıkmaktadır.Industrial cleaning robots are used in large and complex environments, especially in factories and large retail spaces. It is critical for these robots to operate effectively without hitting or approaching obstacles. The boustrophedon coverage-based full coverage path planning algorithm is frequently preferred in industrial applications because it enables robots to scan an area completely and regularly. In this study, a customized boustrophedon coverage-based path planning algorithm is presented on the Robot Operating System (ROS) platform. The proposed algorithm optimizes the robot's movement area by using a parametric inflation radius instead of a safety margin compared to the classical boustrophedon algorithm. This method allows the robot to cover the area more efficiently without approaching obstacles. In the tests performed, the proposed algorithm achieved a higher coverage rate of 98.2% compared to the classical boustrophedon algorithm, while reducing the number of turns by 61%. Significant improvements were also observed in performance metrics such as travel time and path length. In the tests, the calculation time was measured as 44 seconds and the path tracking time as 101 seconds. The total distance covered by the robot is 19.43 meters and the rotation amount is determined as 19.56 radians. These results show that the proposed algorithm can work with higher coverage rate in both obstacle and unobstructed environments in a shorter time. The algorithm offers a significant development for industrial cleaning robots and stands out as an effective solution in large-scale applications