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Attentional Modulation of Outlier Processing
No full textEnsemble perception enables the visual system to function effectively when the number of stimuli in the environment exceeds its capacity. Ensemble representations not only help the limited capacity of visual representations, but they also facilitate the detection and representation of items deviating from the group (i.e., the outlier). This study focuses on how attentional mechanisms modulate outlier processing. In three experiments, we presented participants with an ensemble that was formed by circle stimuli in varying sizes, and the outlier item was distinct in terms of its location. We measured outlier localization performance while manipulating attentional orienting via a spatial cueing paradigm. In Experiment 1, a valid, invalid, or neutral cue was presented before or after the display. Facilitation of outlier localization was most pronounced in the valid precue condition. Experiment 2 included a task to actively engage ensemble perception in addition to outlier localization, and cue validity effect was observed as in Experiment 1. Experiment 3A was carried to directly compare the top-down and bottom-up influences on outlier processing by presenting two spatial outliers-one target and another distractor outlier. The target outlier identity was previously determined and was identical across trials. In Experiment 3B, the target was in red, making it salient among the remaining items. In the invalid trials, where the distractor outlier was cued, responses were closer to the distractor item indicating that outlier processing is cue driven. These experiments overall demonstrate that automaticity of outlier processing can be overridden by cue-driven processes.TUBITAK (The Scientific and Technological Research Council of Turkey [121K064]This work was supported with a grant from TUBITAK (The Scientific and Technological Research Council of Turkey, Project no: 121K064) granted to A.GScience Citation Index Expanded - Social Science Citation Inde
Enhancing Substrate Selectivity And Activity Of G. Kaustophilius Lipase Using Mutation Studies
No full textLipazlar, yağların hidrolizini katalize eden hidrolaz sınıfı enzimlerdir. Biyoteknolojide özellikle biyodizel üretimi alanında önemli bir yeri bulunmaktadır. Bu enzimler, yağların transesterifikasyon reaksiyonunu katalize ederek bitkisel veya hayvansal yağlardan biyodizel elde etmeye yardımcı olmaktadır. Fakat, biyodizel üretiminde lipaz kullanımının bir takım sorunları bulunmaktadır. Reaksiyon verimliliğinin yetersizliği, özellikle yüksek serbest yağ asidi içeriğine sahip ham yağların transesterifikasyonunda önemli bir sorundur. Ayrıca, lipazların reaksiyon hızı açısından yeterince hızlı olmama duumu söz konusudur. Bunlara ek olarak, bu enzimler çevre koşullarına duyarlıdır; uygun sıcaklık veya pH koşulları olmaması durumu enzim aktivitesini olumsuz etkileyebilirken, kararlılık sorunlarını da beraberinde getirebilmektedir. Araştırmacılar, lipazların performansını artırmak ve süreç verimliliğini iyileştirmek için sürekli olarak yenilikçi yöntemler ve teknolojiler araştırmaktadır. Enzim mutasyonu ve lipaz immobilizasyonu, bu çabada odaklanılan önemli alanlardır. Bu çalışma, Geobacillus kaustophilus termofilik lipazının yapısal ve dinamik özellikleri hakkındaki anlayışımızı geliştirmeyi ve aktivitesini, substrat seçiciliğini ve termal kararlılığını iyileştirmek için mutasyonları kullanmayı amaçlamaktadır. İdeal mutasyonları bulmak için Gklip lipazı modellenmiş ve hem yabani tip hem de mutasyonlu yapıların ligand seçiciliğini değerlendirmek için farklı uzunlukta karbon zincirli yağ asitleri ile dok çalışmaları yürütülmüştür. Daha sonra, tüm protein-ligand kompleksleri için 50 ns moleküler dinamik simülasyonları gerçekleştirilmiştir. Simülasyonların son 30 ns'si MM/GBS analizi için kullanılmıştır. 36 mutasyondan, en iyi 5 tanesi daha ileri deneysel çalışmalar için seçilmiştir.Lipases are hydrolase class enzymes that catalyze the hydrolysis of fats. Their applications in biotechnology are particularly noteworthy in the field of biodiesel production. These enzymes help to obtain biodiesel from vegetable oils or animal fats by catalyzing the transesterification reaction of fats. However, there are some problems with the use of lipase in biodiesel production. Firstly, reaction efficiency is a significant problem, especially in trans-esterifying crude oils with high free fatty acid content. Also, lipases may not be fast enough in terms of reaction speed. Additionally, these enzymes are sensitive to environmental conditions; inappropriate temperature or pH conditions can negatively affect enzyme activity, while stability issues also exist. Researchers are continuously exploring innovative methods and technologies to enhance the performance of lipases and improve process efficiency. Enzyme mutation and lipase immobilization are vital areas of focus in this endeavor. This study aims to improve our understanding of the structural and dynamic properties of Geobacillus kaustophilus thermophilic lipase and use mutations to improve its activity, substrate selectivity, and thermal stability. The Gklip lipase was modeled to find the ideal mutations and docking studies were conducted to assess ligand selectivity of both wild-type and mutated structures with different-length carbon chain fatty acids. Then, 50 ns of molecular dynamic simulations were performed for all protein-ligand complexes. The last 30 ns of the simulations were used for MM/GBS analysis. Out of the 36 mutations, the top 5 were taken for further experimental studies
Developmental State in the Context of Globalization: Definitional, Conceptual, and Methodological Issues
No full textDevelopmental state has offered one of the most widely used analytical toolkits to study political economy of development. One of the intriguing debates in the scholarship is whether 'conceptual stretching' undermined the analytical usefulness of the framework. While for some scholars the developmental state has just become a buzzword because the framework is applied to many different regions inappropriately, for others there are varieties of developmental states in the context of globalization. We address this debate by systematically and critically examining the developmental state scholarship, including its main trends and evolution, key discussions, methodology, and emerging areas of research. We conclude that the developmental state remains a valuable approach for researchers in the post-neoliberal political economy context, but scholars would benefit from more precise definitions, clearer justifications of why a particular conceptualization is chosen over others, and more rigorous application of research methods.Scientific and Technological Research Council of Turkiye [121K782]This work was supported by the Scientific and Technological Research Council of Turkiye [121K782].Social Science Citation Inde
A Low-Latency and Area-Efficient QCA-Based Quantum-Dot Design for Next-Generation Digital Sustainable Systems
No full textDigital sustainable system plays a vital role in the advancement of dynamic industries, including agriculture, healthcare, smart cities, Edge Artificial Intelligence (AI), and the Internet of Things (IoT), by facilitating highspeed, low-power, and highly compressed processing. These systems are based on the capabilities of real-time execution, processing, and analysis of large-scale information with extreme power and area limitations. However, traditional Arithmetic Logic Units (ALUs) based on complementary metal-oxide semiconductors (CMOS) are becoming challenging in terms of scalability, power consumption, space demand, and nanoscale fabrication. The ALU is one of the most important parts of such systems and has a direct effect on the overall computing performance, but current implementations cannot sustain the requirements of next-generation applications. To overcome these shortcomings, this paper offers an area-efficient and low-latency ALU that can be designed with the quantum-dot cellular automata (QCA) technology, with the advantage of employing area-efficient layout and simple cell design. The proposed QCA-based ALU has high performance, less delay, and less energy consumption, which makes it properly suitable for the next generation of digital sustainable systems applications. The outcome of the simulation indicates that there are considerable performance gains, such as an 82.37% decrease in energy consumption, and a 9.21% decrease in area relative to current available design. These enhancements emphasize the power of QCA technology as a scalable and low-energy consumption alternative to CMOS in the realization of critical computing components in sustainable digital systems
A Nano-Design of Image Masking and Steganography Structure Based on Quantum Technology
No full textSecure image storage and transmission require sound encryption methods that resist key exposure while maintaining high image quality. Various encryption approaches have been developed to protect image content and its transmission from unauthorized access. One such method is image masking, where a special mask is generated to conceal information within the original image. Instead of hiding the image visually, the mask creates an intermediate layer that obfuscates the encryption key, eliminating the need to transmit it directly. However, implementing such masking techniques efficiently at the hardware level poses particular challenges. Traditional Complementary Metal-Oxide-Semiconductor (CMOS)-based Very-Large-Scale-Integration (VLSI) systems face scalability issues, excessive heat, and high-power consumption. To overcome these challenges, this study utilizes a nano-scale image masking architecture based on Quantum-dot Cellular Automata (QCA), offering reduced area, lower power dissipation, and faster processing. The core operations utilize a three-input XOR gate, designed as a single-layer QCA structure without rotated cells. While QCA-based approaches improve hardware efficiency, most existing implementations focus only on grayscale images, leaving a gap in colorful image encryption. To address this, the work presents a QCA-based encryption and masking architecture for colored images. The method encrypts an image using a random key to generate a cipher image, which is then XORed with the original image to produce a mask. This process, applied independently to each RGB channel, produces three cipher-mask pairs, embedding steganographic property by concealing key information within the image. The keys are generated using a true random number generator (TRNG) based on cross-coupled loops and crossoriented structures, ensuring high entropy. The design was modeled in QCADesigner 2.0.3, with the encryption/decryption algorithms implemented in Python. Experimental results demonstrated a meaningful reduction in cell count and consumed area compared to the prior designs. Image quality and security analysis confirmed visual fidelity and improved robustness
Leveraging Explainable Artificial Intelligence for Transparent and Trustworthy Cancer Detection Systems
No full textTimely detection of cancer is essential for enhancing patient outcomes. Artificial Intelligence (AI), especially Deep Learning (DL), demonstrates significant potential in cancer diagnostics; however, its opaque nature presents notable concerns. Explainable AI (XAI) mitigates these issues by improving transparency and interpretability. This study provides a systematic review of recent applications of XAI in cancer detection, categorizing the techniques according to cancer type, including breast, skin, lung, colorectal, brain, and others. It emphasizes interpretability methods, dataset utilization, simulation environments, and security considerations. The results indicate that Convolutional Neural Networks (CNNs) account for 31 % of model usage, SHAP is the predominant interpretability framework at 44.4 %, and Python is the leading programming language at 32.1 %. Only 7.4 % of studies address security issues. This study identifies significant challenges and gaps, guiding future research in trustworthy and interpretable AI within oncology.Science Citation Index Expande
The Artuqid Ruler of Diyarbakir Nasir Al-Din Mahmud (1200-1222) with His Contributions to the Architectural Environment of His Age
No full textNâsırüddin Melik Salih Mahmud (M 1200-1222), Diyarbakır ve Mardin Bölgesinde 1102-1409 yılları arasında üç kol hâlinde hüküm sürmüş Artuklu Beyliği'nin Hasankeyf ve Diyarbakır kolunun sultanıdır. Hükümdarlığı süresince imar faaliyetlerine önem veren Nâsırüddin Melik Salih Mahmud’un siyasi kimliğinin ötesinde çağının önemli yapılarının hem banisi hem de mimarı olduğu yapıların inşa kitabelerinden açıkça anlaşılmaktadır. Yedi Kardeş Burcu (M 1208-1209) ve Devegeçidi Köprüsü, Nâsırüddin Melik Salih Mahmud’un planları doğrultusunda inşa edildikleri kitabelerindeki tersim (tasarımı yapan) ifadeleriyle belirtilen iki mimari eseridir. Her ne kadar inşa kitabelerinde belirtilmemiş olsa da Ulu Beden Burcu ve Artuklu Sarayı’nın mimari özellikleri ile Nâsırüddin Melik Salih Mahmud’u simgelediği düşünülen çift başlı kartal armalı süslemeleri göz önünde bulundurulduğunda yine onun tasarımıyla inşa edildiği kabul edilmektedir. 1200 – 1222 yılları arasında hüküm sürmüş Artuklu Sultanı Nâsırüddin Melik Salih Mahmud dönemi imar faaliyetle- rinin ele alındığı bu çalışmada, bu dönemde Diyarbakır’da inşa edilen yapılar incelenmiştir. Literatür çalışmalarıyla edinilen bilgiler, “Diyarbakır Surları Koruma Projesi” kapsamında gerçekleştirilen restorasyon çalışmaları sırasında elde edilen bulgularla birlikte değerlendirilerek, Nâsırüddin Melik Salih Mahmud dönemi çok yönlü olarak irdele- nerek bani-mimar ilişkisi ve yöneticinin tasarım sürecine katkısı ortaya konulmaya çalışılmıştır. Ayrıca, Diyarbakır’ın en eski kilisesi olduğu kabul edilen ve MS 3 yüzyıla tarihlendirilen St. George Kilisesi’nin Artuklu Dönemi eki olan avlu bölümünü tarihlendirmeye ve inşa edildiği dönemdeki işlevi konusuna açıklık getirmesi amaçlanmıştır
Solar Photovoltaic Development in West Africa Will Face Million-Ton Waste Challenges, and Off-Grid Systems Will Dominate
No full textSolar photovoltaic (PV), especially off-grid systems, is a low-hanging fruit option among various renewable energy technology choices to address universal energy access, energy security, and climate challenges for vulnerable regions like West Africa. West Africa dominates in the uptake of solar PV solutions, while little attention has been paid to the potential PV waste generation. In this study, we developed a technology-specific, prospective material flow analysis model to investigate material stocks and flows of both on-grid and off-grid solar PV systems for 15 West African countries up to 2050. We show that the cumulative solar PV waste generation ranges from 2.3 to 7.8 million tons by 2050 in West Africa under different scenarios, around 70% of which comes from off-grid PV systems. The potential secondary materials supply ranges from 213 to 704 kilotons, which have potential economic value amounting to 143-475 million dollars or material equivalent to produce 6-19 GW of solar PV capacity. These results call for urgent policy attention, technology development, and infrastructure investment for future PV waste management and highlight the significance of addressing off-grid PV waste in Africa.National Natural Science Foundation of China [72334001, 52400233]; National Natural Science Foundation of China [23JZD018]; Humanities and Social Sciences Fund of the Ministry of Education of China [GZC20230040]; Postdoctoral Fellowship Program of China Postdoctoral Science FoundationWe gratefully acknowledge funding from the National Natural Science Foundation of China (72334001, 52400233), the Humanities and Social Sciences Fund of the Ministry of Education of China (23JZD018), and the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation (GZC20230040)
A New Fault-Tolerance Majority Voter Circuit for Quantum-Based Nano-Scale Digital Systems
No full textQuantum-dot cellular automata (QCA) technology has gained attention lately due to its ability to reduce energy dissipation and minimize circuit area. However, the existing research shows that a critical challenge arises from the lack of circuit resistance in QCA systems when confronted with defects. This issue directly impacts circuit stability and output generation. Moreover, the 3-input majority gate (MV3) is a foundational component within QCA circuits, making its improvement crucial for developing fault-tolerant circuits. One approach is to design MV3 that incorporates essential quantum cells within a single clock cycle. Thus, this paper presents a unique cellular structure for the MV3 gate, utilizing simple quantum cells. The proposed gate, comprising only twelve cells, serves as a building block for QCA circuits. It boasts several key features, including low power consumption, efficient output polarity (+/- 9.93e00-1), and high reliability. Furthermore, to show the efficiency of the suggested gate, it is employed in realizing a 2:1 multiplexer and a full adder/subtractor. Lastly, the proposed MV3 gate is utilized to develop a simultaneous multi-logic gate which is producing several vital digital circuits, such as AND, OR, NOT, NAND, Copy, Subtractor, and Adder. The circuits are designed using QCADesigner and QCAPro, with power estimation included in the process. The comparative analysis reveals that the proposed structures significantly enhance the trade-off between complexity, fault tolerance, and power consumption compared to previous designs.Science Citation Index Expande
The Impact on Risk Management and Price Discovery due to Governmental Intervention: A Case of Two Commodity Futures
No full textThe study explored the impact of government intervention on price discovery and hedging efficacy concerning the agricultural commodities futures market, specifically on Chickpea (Chana) and wheat futures traded on India's NCDEX. This study examines variations in price discovery events before and after the intervention, utilizing the Garbade-Silber (GS) model and Granger causality tests. The Minimum Variance Hedge Ratio (MVHR) assesses the efficacy of hedging. The results demonstrate significant changes: post-intervention, the futures price of chickpeas exhibits enhanced efficacy in price discovery, but the future-led relationship within the wheat market diminishes. Moreover, chickpea futures exhibit stable hedging efficacy, but wheat futures experience a decline in effectiveness, likely attributable to heightened volatility. The findings indicate the varying effects of regulation on commodity markets, suggesting that targeted interventions could enhance market stability and efficiency. It is beneficial for policy analysts, market participants, and researchers in agricultural futures markets. © 2025 Elsevier B.V., All rights reserved