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Genetic Diversity and Population Structure Analysis of Drought Tolerance in Walnut (Juglans regia L.) Using SSR Markers
No full textWalnut biodiversity represents a critical genetic resource for developing climate-resilient cultivars capable of withstanding increasing drought stress under changing environmental conditions. Understanding the genetic basis of drought tolerance mechanisms is essential for sustainable nut production and conservation of valuable genetic resources. This study investigated the genetic and physiological basis of drought tolerance in walnut (Juglans regia L.) saplings, providing crucial insights for breeding programs aimed at developing climate-resilient cultivars. A comprehensive analysis was conducted using 65 walnut samples collected from diverse geographic locations, employing SSR (simple sequence repeat) markers for genetic characterization combined with detailed morphological and physiological assessments under controlled drought stress conditions. Our findings revealed significant variability in drought stress responses among walnut saplings. Morphological and physiological traits exhibited substantial variation under drought stress, reflecting the genetic diversity present in natural populations. Population structure analysis performed using STRUCTURE software identified three distinct genetic clusters within the studied population, with varying degrees of admixture indicating complex evolutionary relationships and gene flow patterns across different populations. Some individuals showed strong affiliation to a single cluster, while others exhibited significant admixture patterns. Mixed Linear Model analysis identified significant marker-trait associations between SSR markers and drought tolerance traits. Multiple markers showed strong correlations with physiological parameters including chlorophyll content, leaf characteristics, and stress response indicators. Hierarchical clustering and phylogenetic analyses confirmed the genetic relationships among populations and revealed patterns consistent with geographic distribution and environmental adaptation. This research elucidates the genetic architecture underlying drought tolerance in walnuts and demonstrates the effectiveness of SSR markers for identifying drought-responsive genes. The identified marker-trait associations provide valuable tools for marker-assisted selection in breeding programs. Furthermore, the observed genetic diversity and its correlation with drought-related traits offer a foundation for developing more resilient walnut cultivars. These findings contribute to the conservation and utilization of walnut genetic resources while supporting the development of climate-adaptive breeding strategies for sustainable nut production under water-limited conditions
Approximation by α-Chlodowsky–Durrmeyer Operators
No full textThe main objective of this article is to construct a new sequence of (Formula presented.) -Chlodowsky–Durrmeyer type operators including shape parameter (Formula presented.), where (Formula presented.). We compute some needed moment estimates. Also, we study some direct and local approximation properties of the proposed operators. Next, we obtain the order of convergence in terms of the weighted modulus of continuity. Then, in order to check the asymptotic behavior of related operators, we prove Voronovskaya's type theorem. Further, we evaluate pointwise convergence of the proposed operators. To validate our theoretical results, we perform some graphical and numerical experiments that illustrate the precision, effectiveness, and advantages of the proposed approach in practical applications of the related operators
Yapay Zekânın Sosyolojik Gözü-Hukukun Yeni Sınırları
No full textBu makale, yapay zekâ temelli büyük dil modellerinin yalnızca teknik sistemler olarak değil, toplumsal davranışları, kolektif duygu durumlarını ve sosyal eğilimleri görünür kılan yeni bir dijital gözlem rejimi olarak nasıl işlediğini incelemektedir. Çalışma, Anthropic tarafından geliştirilen ve kullanıcı–yapay zekâ etkileşimlerini anonimleştirerek analiz eden Clio sistemi örneği üzerinden, yapay zekânın sosyolojik bir araç hâline gelmesinin hukuk düzenleri bakımından doğurduğu sonuçları tartışmaktadır.Makalenin temel amacı; anonimlik, çıkarımsal veri, rıza, kitlesel profilleme ve panoptikon etkisi gibi kavramların, mevcut veri koruma ve bilişim hukuku çerçeveleri içinde artık yeterli açıklayıcılığa sahip olup olmadığını sorgulamaktır. Bu bağlamda çalışma, anonimleştirilmiş verilerden türetilen davranışsal örüntülerin bireysel mahremiyetle olan ilişkisini, klasik “kişisel veri–anonim veri” ayrımının ötesine taşıyarak ele almaktadır.Makale, GDPR ve KVKK başta olmak üzere pozitif hukuk normlarını eleştirel bir perspektifle değerlendirirken, özellikle rıza mekanizmalarının toplumsal analiz ve kolektif profilleme pratikleri karşısında ne ölçüde “aydınlatılmış” sayılabileceğini tartışmaktadır. Ayrıca, bireyleri tekil olarak hedeflemese bile demografik gruplar üzerinden kurulan kitlesel profillemenin, ifade özgürlüğü ve düşünce özerkliği üzerinde dolaylı fakat derin etkiler yarattığı ileri sürülmektedir.Sonuç olarak çalışma, yapay zekâ destekli analiz sistemlerinin, hukukun yalnızca bireysel veri ihlallerine odaklanan klasik koruma yaklaşımını aşmasını zorunlu kıldığını savunmakta; dijital gözetimin yarattığı panoptikon etkisine karşı, bireysel olduğu kadar toplumsal düzeyde koruma sağlayan yeni normatif çerçevelere duyulan ihtiyacı ortaya koymaktadır.This article examines how large language models based on artificial intelligence function not merely as technical systems, but as a new digital observation regime that renders social behaviors, collective emotional states, and societal tendencies visible. Focusing on the case of Clio, a system developed by Anthropic that analyzes anonymized user–AI interactions, the study discusses the legal implications of artificial intelligence becoming a sociological instrument.The primary objective of the article is to question whether concepts such as anonymity, inferential data, consent, mass profiling, and the panopticon effect still possess sufficient explanatory power within existing data protection and information law frameworks. In this context, the study moves beyond the classical dichotomy of “personal data versus anonymous data” by examining the relationship between individual privacy and behavioral patterns derived from anonymized datasets.Adopting a critical perspective, the article evaluates positive law norms—particularly the GDPR and the Turkish Data Protection Law (KVKK)—and interrogates the extent to which current consent mechanisms can be considered genuinely “informed” when data are used for societal analysis and collective profiling practices. It further argues that mass profiling conducted through demographic groupings, even without targeting individuals directly, produces indirect yet profound effects on freedom of expression and cognitive autonomy.In conclusion, the study contends that AI-driven analytical systems necessitate a departure from the law’s traditional focus on individual data violations alone. It highlights the need for new normative frameworks capable of providing protection at both the individual and societal levels in response to the panopticon effect generated by contemporary forms of digital surveillance.</p
Substituted bipyridine-based compounds: Synthesis, enzyme inhibition, anticancer activities and molecular docking studies
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Advancements in nonlinear PID controllers: A comprehensive review
No full textProportional-integral-derivative (PID) controllers have been widely used in control engineering due to their simplicity, robustness, and effectiveness. However, traditional linear PID (L-PID) controllers face challenges in handling nonlinear dynamics, uncertainties, and varying operating conditions. To overcome these limitations, nonlinear PID (N-PID) controllers have emerged as a powerful alternative, offering improved adaptability, robustness, and transient response. Despite their increasing adoption, a comprehensive review of N-PID controllers, including their theoretical advancements, tuning methodologies, and applications, remains lacking. This paper provides an in-depth review of N-PID controllers, highlighting their advantages over L-PID controllers and their effectiveness in various engineering applications. It discusses the necessity of N-PID controllers, explores key advancements in their structural modifications, and analyses different tuning approaches, including adaptive, bio-inspired, and optimization-based methods. Additionally, the review covers their applications in process control, power converters, motor drives, and robotic manipulators, demonstrating their superior performance in handling complex dynamic systems. The paper concludes by identifying future research directions, emphasizing the potential of N-PID controllers in advancing control engineering by improving system stability, energy efficiency, and precision control. This review serves as a valuable resource for researchers and engineers seeking innovative control solutions for nonlinear and uncertain systems
Comprehensive Review of Analytical Approaches for Vinblastine and Vincristine in Cancer Research
No full textVinblastine (VBL) and vincristine (VCR) are vinca alkaloids derived from Catharanthus roseus and are among the most widely used chemotherapeutic agents for treating hematological malignancies and solid tumors. Due to their narrow therapeutic index and complex structural nature, accurate, sensitive, and selective analytical methods are crucial for quantifying these drugs in pharmaceutical formulations, biological matrices, and environmental samples. This review provides a comprehensive overview of reported analytical techniques for VBL and VCR, drawing on major databases such as Scopus, Web of Science, ScienceDirect, PubMed, and Google Scholar, with a focus on the English-language literature. The discussed methods include chromatographic, spectroscopic, electroanalytical, and capillary electrophoretic techniques. High-performance liquid chromatography (HPLC), particularly when coupled with LC–MS/MS, offers exceptional sensitivity, with detection limits as low as 0.025 ng/mL in plasma. Conventional HPLC-UV methods, though less sensitive, remain widely applied in plant extract analysis. Electroanalytical approaches, such as voltammetry using nanomaterial-modified electrodes, offer eco-friendly and cost-effective alternatives with detection limits as low as 0.3 nM. Key analytical considerations include light sensitivity, pH and temperature control, and matrix interferences. Overall, recent methodological advancements enable reliable quantification of VBL and VCR, supporting safer clinical application, toxicity monitoring, and environmental surveillance
Karpuz (Citrullus lanatus L.) fidesi gelişim parametreleri ve klorofil içeriği üzerine Azospirillum lipoferum ve deniz yosunu uygulamalarının etkileri
No full textInvestigation of Mortality and Additional Morbidity Factors in Stroke Patients Who Have Undergone Decompressive Surgery
No full textWe aimed to investigate the factors that may determine the effects of decompressive craniectomy by analyzing the data of patients who experienced ischemic and hemorrhagic stroke following the decompressive surgical procedure performed at our stroke center. Thus, we sought to establish a consensus on decompressive surgery practices. Within the scope of this research, we conducted a retrospective analysis of the files of all stroke patients who underwent decompressive craniectomy and were followed between 2015 and 2020. The contributing factors influencing prognosis were examined. A total of 27 patients were included in the study. We recorded and statistically compared the sociodemographic characteristics of these patients, along with their NIH score at admission, GCS, an d mRS after 3-6 months. Out of the 27 patients, 16 (59.3%) had ischemic stroke and 11 (40.7%) had hemorrhagic stroke. The average age of the patients was 56±13.2 years. The mean NIHSS score was 16±7.2. After decompressive surgery, 70% of patients were deceased prior to discharge. The average craniectomy dimensions for all patients were calculated as 9.4±1.5 cm x 7.7±1.5 cm. We observed that factors such as the timing of decompressive surgery, Glasgow coma score, length of hospital stay, stroke hemisphere, glucose, and hemoglobin values did not affect prognosis post-surgery. Patients who underwent decompressive surgery due to hemorrhagic stroke demonstrated better outcomes after the procedure. The selection of patients for surgery and the timing of the procedure should be guided by each clinic's own experience
Assessing the impact of Krymsk 5, Piku 1 and Gisela 6 rootstocks on morphological and quality characteristics of sweet cherry
No full textBackground: Modern orchards are established with intensive planting systems that ensure early fruiting, high fruit yield and quality, and minimize labor costs, especially during harvesting. To meet the expectations of intensive planting systems, the most important factor is the selection of suitable rootstocks for climate and soil conditions. This study was conducted to determine the effects of combinations created with cold-resistant Krymsk 5, semi-dwarf rootstocks Gisela 6 and Piku 1, which are suitable for dense planting, and the sweet cherry varieties 0900 Ziraat and Regina, on their morphological, pomological, and biochemical properties. Results: Tree height, fruit weight, and total phenolic content in trees grafted onto Krymsk 5 rootstocks, and fruit firmness in trees grafted onto Gisela 6 rootstocks, were higher than in other rootstocks. The 0900 Ziraat cultivar showed significantly higher fruit weight, fruit width, and fruit length than the Regina cultivar. In contrast, the a*, b* values, vitamin C, anthocyanin, and antioxidant content in the Regina cultivar were significantly higher than those in the 0900 Ziraat. The rootstock x cultivar interactions had a significant effect on some properties. Conclusion: It was revealed that trees grafted onto Krymsk 5 rootstocks exhibited greater vegetative growth, and the fruit obtained from these trees was richer in terms of phytochemical content. Krymsk 5 is a potential rootstock for grafting with elite local cherry scions