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A New Monohydrogen Phosphate-Selective Carbon Composite Membrane Electrode for Soil Water Samples
Full text linkThis study focused on developing a novel composite phosphate-selective electrode
for on-site and real-time applications using a silver polyglutaraldehyde phosphate
and carbon nanotube (CNT) matrix. CNT-silver polyglutaraldehyde phosphate compound
was synthesized and characterized using Fourier-transform infrared spectroscopy (FTIR),
scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis
(TGA). The potentiometric performance of the composite phosphate-selective electrode
was then investigated. The results demonstrated that the composite phosphate-selective
electrode exhibited good sensitivity, with a linear response in the concentration range of
1.0 × 10−4 to 1.0 × 10−2 M for phosphate ions. The electrode also showed high selectivity
towards phosphate ions compared to other anions, such as chloride and nitrate. Additionally,
the electrode displayed a quick response time of less than 15 s, making it suitable for
real-time measurements. The electrode was applied to surface and soil water samples. The
results obtained from the water samples showed a strong correlation with those obtained
from the preferred spectrophotometry method, highlighting the potential of the developed
electrode for on-site and continuous monitoring of phosphate and offering an efficient and
practical solution for various fields that require phosphate detection
Compactness of Hankel and Toeplitz Operators on Convex Reinhardt Domains in C2
No full textWe study compactness of Hankel and Toeplitz operators on Bergman spaces of convex
Reinhardt domains in C2 and we restrict the symbols to the class of functions that are
continuous on the closure of the domain. We prove that Toeplitz operators as well
as the Hermitian squares of Hankel operators are compact if and only if the Berezin
transforms of the operators vanish on the boundary of the domain
2D MOF Structure, Electrochemical Biosensing in Bioelectronic Applications
No full textTwo-dimensional (2D) metal-organic frameworks (MOFs) have emerged as a groundbreaking class of materials with wide-ranging applications across biotechnology, bioelectronics, and tissue engineering. With their unique properties such as high surface area, tunable porosity, and flexibility in incorporating various metal ions, MOFs are instrumental in advancing the capabilities of bioelectronic sensors, tissue scaffolds, and biomedical imaging technologies. In biosensing, MOFs enable highly sensitive detection of biomolecules, including glucose, DNA, and proteins, by facilitating selective molecular interactions. This is particularly crucial for wearable technologies, where early detection of physiological changes is essential for timely diagnosis of diseases such as cancer and Alzheimer’s. MOFs’ adjustable porosity allows for selective adsorption of biomolecules, making them highly promising in biosensor development. Additionally, MOF-based sensors exhibit outstanding biocompatibility and mechanical strength, which are critical for seamless integration into wearable substrates. MOFs have also shown great potential in tissue engineering, where they enhance the functionality of scaffolds through their ability to load and release bioactive molecules. This controlled release mechanism is pivotal for promoting tissue regeneration, angiogenesis, and even drug delivery for cancer therapies. The versatility of MOFs in modulating physical properties such as mechanical strength, coupled with their capacity for functionalization, opens new avenues for creating bioactive scaffolds tailored to specific biomedical needs. In the realm of biomedical imaging, MOFs contribute significantly as contrast agents, particularly in magnetic resonance imaging (MRI) and computed tomography (CT). Their high surface area and tunable structure improve the precision and clarity of imaging, making them indispensable for enhancing diagnostic accuracy. MOFs also enable the development of multimodal imaging systems, combining diagnostic and therapeutic functionalities into a single platform. Furthermore, MOFs are being explored for their bioelectrochemical properties, where their integration into electrodes enhances the efficiency of biosensors and energy storage devices. The synergistic effects of MOFs with nanomaterials such as MXenes and carbon-based substances boost their electrocatalytic activity, which is crucial for applications in wearable sensors and bioelectronic systems. The future of MOF-based materials is promising, particularly as researchers focus on improving their biocompatibility, scalability, and operational stability. With further development, MOFs are expected to revolutionize the fields of bioelectronics, tissue engineering, and biomedical imaging, offering innovative solutions to some of the most pressing challenges in medical science
Dijital Siyasal İletişim ve Tiktok: 2024 Abd Başkanlık Seçimlerinde Kullanıcı Yorumlarının Duygu Analizi
No full textPolitical communication can be defined as strategic communication with the aim of influencing the perceptions and attitudes of the target audience. Voters need information about the candidates they intend to support and election campaigns allow voters to share their opinions, suggestions and thoughts with politicians. During these periods, political parties tend to use mass media and digital media to provide voters with the information they may need. Today, TikTok as an important platform in the digital political communication process, it plays a critical role for politicians to interact with the target audience and shape public perception. This role also attracted attention during the United States of America (USA) presidential elections held on November 5, 2024. In this context, in this study, which focuses on the digital political communication process in the 2024 US Presidential Elections, the emotional distribution of public perception towards the Republican Party candidate Donald Trump and Democratic Party candidate Kamala Harris, who competed in the election, was analyzed through the sentiment analysis method based on the comments made on the TikTok posts of the candidates. According to the research findings, comments on Donald Trump's posts are characterized by a positive emotional tone. However, deeper and more lasting interactions, such as feelings of support and loyalty and social/contextual comments, were observed to be limited. Although the comments on Kamala Harris are largely positive, the low level of loyalty and commitment of her supporters is noteworthy. As a noteworthy finding, it was observed that Trump supporters were more likely to comment with loyalty and commitment than Kamala Harris supporters. In conclusion, the social media interactions of both candidates provide a view of the emotional states of their supporters and how they interact in the social context.Siyasal iletişim; hedef kitlenin algı ve tutumlarına etki etme amacıyla gerçekleştirilen stratejik bir iletişim faaliyeti olarak tanımlanabilir. Seçmenler, desteklemeyi düşündükleri adaylar hakkında bilgiye ihtiyaç duymaktadır ve seçim kampanyaları seçmenlerin görüş, öneri ve düşüncelerini siyasetçilerle paylaşabilmelerine olanak tanımaktadır. Siyasal partiler bu dönemlerde kitle iletişim araçları ve dijital medya olanaklarıyla doğrudan seçmene ihtiyaç duyabileceği bilgileri aktarma imkanına sahip olabilmektedir. Günümüzde TikTok, seçmenlerle iletişim yoluyla siyasi mesajları yaymak ve kitlelere ulaşmak için tercih edilen sosyal medya platformları arasında yer alması ile dikkat çekmektedir. Ayrıca dijital siyasal iletişim sürecinde önemli bir platform olarak politikacıların hedef kitle ile etkileşim kurmasında, kamuoyu algısının şekillendirilmesinde kritik rol oynamaktadır. Bu rol 5 Kasım 2024 tarihinde gerçekleştirilen Amerika Birleşik Devletleri (ABD) başkanlık seçimlerinde dikkat çekmiştir. Bu bağlamda 2024 ABD başkanlık seçimlerinde dijital siyasal iletişim sürecini konu edinen bu çalışmada, seçimde yarışan Cumhuriyetçi Parti adayı Donald Trump ve Demokratik Parti Adayı Kamala Harris’e yönelik kamuoyu algısının duygusal dağılımları, adayların TikTok paylaşımlarına yapılan yorumlar üzerinden duygu analizi yöntemi ile incelenmiştir. Araştırma bulgularına göre; Donald Trump’ın paylaşımlarına gelen yorumlar, olumlu bir duygusal tonla öne çıkarken; destek, bağlılık duyguları ve sosyal/bağlamsal yorumlar gibi daha derin ve kalıcı etkileşimlerin sınırlı olduğu gözlemlenmiştir. Kamala Harris’e ilişkin yorumlar ise büyük ölçüde olumlu olmasına rağmen destekleyen kitlenin sadakat ve bağlılık oranlarının düşüklüğü dikkat çekmektedir. Dikkat çekici bir bulgu olarak Trump destekçilerinin sadakat ve bağlılık içeren yorumlarının Kamala Harris destekçilerine göre daha fazla olduğu görülmüştür. Sonuç olarak her iki adayın sosyal medya etkileşimleri ve destekçilerinin duygusal durumlarına dair bir görünüm sunulmaktadır
The Sound of a Room: Memory and Auditory Presence of Place
No full textSeán Street’s The Sound of a Room: Memory and Auditory Presence of Place (2020) is an original work that invites the reader to reconsider space – often regarded as a purely physical entity – as a field of auditory experience. By treating sound, which is invisible and therefore prone to neglect, as a significant dimension, the book calls on the reader to forge a different connection with both their surroundings and their own past through deep listening. Street’s text is not woven with academic jargon, yet it provides a sensory ground that can naturally accompany spatial experience through its intuitive strength, narrative power, and poetic depth
Ahmet Zühtü Paşa’nın Avrupa’daki Mali Misyonları (1873-1877)
No full textWhen the Ottoman Empire fell into a severe financial crisis during the Crimean War
(1853-1856), it turned to external borrowing. However, as the first loan taken in 1854
failed to cover the war expenses, it borrowed again in 1855. Afterwards, the Ottoman
government started to borrow in order to withdraw the unrequited paper money issued
in the previous years from the market, to cover the budget deficit and, more importantly,
to pay the interest and debt installments of its debts as of 1865. To summarize, 10 years
after it started borrowing, the Ottoman government was unable to pay its debts. Thanks to
the appetite for easy money in European financial markets, the government continued to
borrow at very high interest rates and, beginning from 1865 onwards, the discussion was
not about whether it would declare bankruptcy, but when it would declare bankruptcy.
In 1873, the stock markets of Europe and the United States suffered a major collapse
and the Great Depression of 1873-1896 began, which would later be characterized as
the first great crisis of capitalism. In addition, between 1873-1875, the Ottoman Empire
suffered a catastrophic famine. It was almost impossible to borrow money from abroad,
and therefore to “roll over debt with debt”. Zühtü Efendi, who was the undersecretary of
the Ministry of Finance at the time, was hastily dispatched to London to obtain a new loan in order to alleviate the heavy budgetary costs of the rebellions in the Empire’s European
territories and the financial burden of the newly started Ottoman-Russian War (1877-
1878).Zühtü Efendi had to find a new reliable collateral for a new loan. To this end, he
saw that he could use the collateral that would be freed up by reducing the interest rates on
bonds issued in previous years. After reaching an agreement with the bondholders, Zühtü
Efendi managed to sign a £5 million loan agreement, known as “the Loan For Protection
of the Ottoman Rights”. This article discusses his borrowing adventure. For this purpose,
both the Ottoman and the British archives were consulted for financial correspondence
and reports from the period. The developments not always documented in the archival
records were evaluated with the help of local and foreign newspapers in İstanbul, as well
as newspapers published in London. The article, based on previously unused documents
and information obtained through this research, aims to contribute to the literature on
Ottoman external borrowing.Osmanlı Devleti Kırım Savaşı (1853-1856) sırasında ağır bir mali buhran içine
girince dış borçlanma seçeneğine yöneldi. Ancak, 1854 senesinde yapılan ilk borçlanma
savaş masraflarını karşılamayınca, 1855’te yeniden borçlanıldı. Daha sonra, önceki
senelerde çıkarılan karşılıksız kâğıt paraların piyasadan çekilmesi, bütçe açığının
kapatılması, bunlardan daha önemlisi, 1865 senesinden itibaren de Osmanlı Hükümeti,
borçlarının faizlerini ve borç taksitlerini ödemek için borçlanmaya başladı. Özetle ifade
edilirse, borçlanmaya başladıktan 10 sene sonra, Osmanlı hükümeti borçlarını ödeyemez
duruma geldi. Avrupa mali piyasalarındaki kolay para kazanma iştahı sayesinde oldukça
yüksek faizlerle borçlanmaya devam eden hükümetin, 1865’ten itibaren, iflasını ilan edip
etmeyeceği değil, iflasını ne zaman ilan edeceği konuşulmaya başladı. 1873 senesinde
Avrupa ve ABD borsaları büyük bir çöküş yaşadı ve daha sonra kapitalizmin ilk büyük krizi
olarak nitelendirilecek olan 1873-1896 Büyük Bunalımı başladı. Buna ek olarak, 1873-
1875 senelerinde Osmanlı İmparatorluğu’nda büyük bir kıtlık felaketi yaşandı. Dışarıdan
borç bulmak, dolayısıyla “borcu borçla çevirmek” neredeyse imkansızdı. İmparatorluğun
Avrupa topraklarındaki isyanların bütçeye yüklediği ağır maliyeti ve yeni başlayan
Osmanlı-Rus Savaşı’nın (1877-1878) mali yükünü hafifletmek üzere yeni bir borçlanma
gerçekleştirebilmek amacıyla, o sırada Maliye Nezâreti müsteşarı olan Zühtü Efendi apar topar Londra’ya gönderildi. Zühtü Efendi, yeni bir borçlanma için güvenilir yeni bir teminat
bulmak zorundaydı. Bu amaçla, önceki senelerde piyasaya sürülmüş borç tahvillerinin
faizlerinde indirim sağlamak suretiyle serbest kalacak teminatı kullanabileceğini gördü.
Zühtü Efendi tahvil alacaklılarıyla anlaştıktan sonra “Muhâfaza-i Hukûk-ı Osmanîye
İstikrâzı” olarak anılan 5 milyon Sterlinlik bir borç anlaşmasını da imzalamayı başardı.
Bu makalede onun bu borçlanma serüveni ele alınmaktadır. Bu amaçla hem Osmanlı
arşivi hem İngiliz arşivi dönemin finansal yazışmaları ve raporları açısından taranmış,
ardından, kimi zaman arşiv kayıtlarında yer almayan gelişmeler İstanbul’daki yerli ve
yabancı gazetelerin yanı sıra Londra gazetelerinden de yararlanılarak değerlendirilmiştir.
Söz konusu araştırmayla ulaşılan ve daha önce kullanılmamış belge ve bilgilere dayanarak
kaleme alınan makalenin Osmanlı dış borçlanmasını işleyen literatüre böylece katkıda
bulunması amaçlanmıştır
Romantik İlişkilerde Kişilerarası Bilinçli Farkındalık ve Benlik Farklılaşması ile Affedicilik Arasındaki İlişkide Ruminasyonun Aracı Rolü
No full textThe present study explores the possible mediating role of rumination in the relationship between forgiveness and interpersonal mindfulness or differentiation of self in romantic relationships. A total of 662 young adults participated in the study. The mediating role of rumination was tested using both Structural Equation Modeling and the Sobel Test. Results revealed that forgiveness showed a significant positive correlation with both differentiation of self and interpersonal mindfulness, whereas it correlated negatively with rumination. It was found that differentiation of self, interpersonal mindfulness, and rumination significantly predicted forgiveness. Differentiation of self and interpersonal mindfulness were also significant predictors of rumination. Moreover, results yielded partial mediation of rumination regarding the relationships between differentiation of self-forgiveness and interpersonal mindfulness-forgiveness. The results of the present study were discussed in the light of the literature, and suggestions were made for future studies. It was considered that the findings of the present study would be beneficial for the experts of both individual psychotherapy and family-couple therapy to determine the dynamics that they need to focus on/prioritize in the process of case assessment, formulation, and psychotherapy while working on interpersonal relationships, specifically romantic relationships. Regarding preventive mental health services, practices that increase interpersonal mindfulness and support the differentiation of self would promote individual well-being and strengthen interpersonal relationships
Electrochemical Biosensors Based on Carbon Nanotubes (CNTs) Used to Diagnosis Pancreatic and Liver Cancer
No full textThis review examines recent advancements in carbon nanotube (CNT)-based electrochemical biosensors for
the diagnosis of pancreatic and liver cancer biomarkers. The unique structural and functional properties of CNTs,
such as their high surface area, excellent electrical conductivity, and biocompatibility, make them highly
effective for sensitive and specific detection of cancer-associated biomarkers. The review summarizes key studies
that have demonstrated the potential of CNT-based biosensors in early cancer biomarker identification. Various
sensor designs, fabrication techniques, and detection mechanisms are discussed to highlight the progress made in
this field. Additionally, the advantages and limitations of CNT-based biosensors compared to conventional
diagnostic methods are analyzed. By providing a comprehensive overview of the latest research, this study
underscores the role of CNTs in enhancing the accuracy and efficiency of cancer biomarker detection. Future
perspectives on improving CNT-based biosensor technology, including strategies for increasing selectivity, stability,
and integration with point-of-care diagnostic systems, are also explored. Also, this review focuses on the
applications of CNT-based biosensors in the identification of pancreatic and liver cancer biomarkers and discusses
current research progress
Path planning and tracking for swarm robots in variable environments
No full textÇalışmada robotun istenilen koordinat sistemine ulaşması, yol planlama ve bu planlanan yolun tekli ve çoklu robotlar tarafından koordineli bir şekilde takibi sağlanmaktadır. Planlanan yolda en kısa mesafeyi bulması için A* algoritması kullanılmıştır. Pure Pursuit algoritması ise yol takip ve yönelimini belirlemek için kullanılmıştır. Pursuit algoritması, robot/ların hedefe doğru hareket etmelerini sağlayarak, birbirleriyle etkileşimini optimize eder ve çevresel engellerle, hareketli objeleri belirleyerek gerçek zamanlı uyumu sağlar. Robot/lar yol takibini en düşük maliyete göre hesaplamaktadır. Bu algoritma robot/lar arasında daha güvenli bir etkileşim oluşturmasının yanı sıra daha kısa bir yol planlaması sunmaktadır. Dinamik engeller ve hareketli objeler dikkate alınarak, robot/ların sürekli olarak yeniden yol planlaması yapabilmesi sağlanmıştır. Bu, robot/ların çevrelerindeki değişikliklere hızlıca adapte olmasını sağlamaktadır. Çoklu robot kontrolünde, lider-takipçi yaklaşımı uygulanarak, bir robot (lider) hedefe doğru yönelirken, diğer robotlar (takipçiler) lider robotu izleyerek hedefe doğru hareket ederler. Engelli ortamda ise robot/lar en kısa yolu takip ederken çevredeki engellerden de kaçınarak güvenli bir şekilde ilerlemektedirler. Çalışmada kullanılan Gazebo simülasyon ortamı, robotların gerçek dünya koşullarını taklit ederek, algoritmaların ve kontrol yöntemlerinin etkinliğini test etmek için ideal bir platform sunmaktadır. Ayrıca Turtlebot3 robotları simülasyonda kullanılarak, robotların çevresel engellerle etkileşimleri ve çoklu robot koordinasyonu konusunda elde edilen performans değerlendirilmiştir.In this study, the robot reaches the desired coordinate system, path planning and coordinated tracking of this planned path by single and multiple robots are provided. A* algorithm is used to find the shortest distance on the planned path. Pure Pursuit algorithm is used to determine the path tracking and orientation. The Pursuit algorithm ensures that the robot(s) move towards the target, optimises their interaction with each other and provides real-time adaptation by identifying environmental obstacles and moving objects. The robots calculate the path following according to the lowest cost. This algorithm provides a safer interaction between the robot(s) as well as a shorter path planning. Dynamic obstacles and moving objects are taken into account so that the robot(s) can continuously re-plan the path. This allows the robots to quickly adapt to changes in their environment. In multi-robot control, by applying the leader-follower approach, one robot (leader) moves towards the target while the other robots (followers) move towards the target by following the leader robot. In the obstacle environment, the robot(s) follow the shortest path while avoiding the obstacles in the environment. The Gazebo simulation environment used in the study provides an ideal platform for testing the effectiveness of algorithms and control methods by simulating real-world conditions. In addition, Turtlebot3 robots were used in the simulation to evaluate the robots' interactions with environmental obstacles and the performance achieved in multi-robot coordination
The Use of an Expendable Mold Casting Technique for Semi-solid Formable Feedstock Production: The Combination of Lost Foam and Cooling Slope Casting
No full textThis study investigates expendable mold casting as an
innovative approach to producing semi-solid formable
aluminum feedstock by integrating the lost foam casting
(LFC) technique with the cooling slope method to generate
semi-solid slurry. Silica and chromite sands were employed
as mold materials, and expanded polystyrene (EPS) patterns
were prepared both with and without refractory
coatings. The effects of sand type, pattern coating, and
cooling slope application on the microstructural and
mechanical properties of A356 alloy were systematically
evaluated in both as-cast and reheated conditions. The
finest and most spheroidal microstructures were achieved
using a combination of chromite sand, uncoated patterns,
and cooling slopes. After reheating, the smallest average grain size (77.1 lm) and highest shape factor (0.93) were
observed. Significant improvements in grain refinement
during solidification and enhanced sphericity following
reheating were demonstrated. Moreover, hardness values
were maintained or slightly improved in samples with finer
microstructures despite the expected grain coarsening after
reheating. Compared to conventional permanent mold
casting methods, the proposed hybrid technique offers
superior control of thermal gradients and solidification
dynamics, resulting in more uniform and spheroidal grains
and, consequently, enhanced semi-solid formability