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Comparative Study on the Effectiveness of Silicone and Polyester-Plastinated Bovine Brains for Face-to-Face and Online Neuroanatomy Education
No full textAnatomy is regarded as one of the most essential and challenging courses in veterinary medicine. The study evaluated the student perceptions of silicone and polyester-plastinated cattle brains in both face-to-face and online neuroanatomy education. A total of six cattle heads were collected from a slaughterhouse, processed using four plastination steps. These specimens were evaluated by 240 first-year veterinary students (from 248 enrolled), with 108 participating in face-to-face evaluation and 132 completing online evaluations of the specimens. The online survey for the assessments revealed that 75.9% of face-to-face participants strongly agreed that anatomical structures were well represented in silicone-plastinated whole brains (mean score: 4.7, SD: 0.6). Sliced silicone plastinates achieved 71.3% agreement on providing enhanced contrast between gray and white matter (mean score: 4.57, SD: 0.8). Polyester plastinates also demonstrated high clarity, with 62% of face-to-face respondents strongly agreeing on their improved differentiation of gray and white matter (mean score: 4.38, SD: 0.95). Students appreciated the odorless, durable, and nontoxic nature of plastinated specimens. Limitations included reduced tactile resemblance (mean score: 2.19) and natural color fidelity (mean score: 2.74). Despite these drawbacks, 69.4% of face-to-face students strongly supported incorporating plastinated specimens alongside cadaveric materials in anatomy courses. Plastinated cattle brain specimens demonstrated excellent anatomical detail and usability, making them valuable resources for anatomy education. The findings support their use in both face-to-face and online teaching environments as preferred alternatives or complements to traditional formalin-preserved specimens.Ankara Universitesi [21L0239025]; Ankara University Scientific Research Projects Unit [21L0239025]Ankara Universitesi, Grant/Award Number: 21L0239025This study was financially supported by Ankara University Scientific Research Projects Unit (Project no: 21L0239025)
Approximate Formula for Adjustment Coefficient of a Non-Linear Risk Model with Weibull Claims
No full textThis study examines a non-linear Cramér-Lundberg risk model, in order to determine the adjustment coefficient (r) when the claims have Weibull distribution. Similar insurance models have been studied in the literature, usually when premiums are linear. However, in some real-world problems, the increase in revenue may not be linear. In such cases, it is significant to consider nonlinear risk models. Accordingly, in this study, a nonlinear Cramér-Lundberg risk model is mathematically constructed and investigated when the premium function is p(t)=ct. As is known, the adjustment coefficient plays a substantial role in evaluating the ruin probability. Thus, a detailed examination of this coefficient is important. However, it is a challenging process to derive the exact value of r from an integral equation when the claims have Weibull distribution. For this reason, the adjustment coefficient is investigated in this study by using approximation methods and a practical algorithm proposed to calculate approximate result with the desired closeness to the true value. © 2025 Elsevier B.V., All rights reserved
End-to-End Trusted Execution Environment (TEE) with Dynamic Holistic View Based Throughput Maximization Approach
No full textAmerican Council on Science and EducationDrastic progress and improvements on classical behavior modelling approaches; such as, cellular automata, chaotic systems, hierarchical block diagram modeling methods enabled to avoid of cumborsomism while adapting the dynamism at massive scale at some extend. However, persisting and ensuring the trust for varying contexts with an E2E trust mechanism require dynamic holistic views to adapt the dynamism at massive scale with extended data locality to the edges in trusted scalable manner. Initial observations for data exchange over a hybrid-cloud node, instead of cell unit scenario in 5G environment with the trust mechanism is promising to meet zero latency requirement of MEC (Multi-access/Mobile Edge Computing) edge units thanks to the improvements provided via memory-centric system design paradigms. It shows that data can be transmitted over a hybrid-cloud node rather than cell units can maximize total system throughput of emerging hybrid-clouds, which have 5/6G connectivity and strong quantum back-end units with the E2E trusted execution environment (TEE) and dynamic holistic views. By that means, it is promising to utilize MEMCA hybrid-cloud as massive scale cyber-intelligence system within the national security legal constraints with the E2E TEE, which have maximized total system throughput via dynamic holistic views of the observed chaotic context. So that, we can say that efficient utilization of MEMCA hybrid-cloud to national security systems as digital dynamics core mechanism can port the massive chaos in socio-dynamics to massive-growth via the dynamic feedback controller structures and embedded check-points to the available physical locations within the (near) real-time cyber intelligence mechanisms with maximized total system throughput values. © 2025 Elsevier B.V., All rights reserved
Institutional Complexity and Consumer Wellbeing: Navigating the Conflicting Logics of Religion, State, and Market During the Covid-19 Pandemic
No full textInstitutional complexity arises when multiple institutional logics prescribe divergent and incompatible behaviors. Studies show that exposure to contradictory prescriptions of multiple logics may trigger identity tensions, strategic challenges, and legitimacy problems. We add to this research stream by exploring the implications of the incompatibility between religion and other logics on consumer wellbeing. Extant research reports a generally positive effect of religion on wellbeing but limits the analytical attention to the individual effects of religiosity. Viewing religion as part of an inter-institutional system, we seek to understand why religion and other institutional logics might come into a conflictual relationship with each other and destabilize wellbeing. We find that critical events, such as the COVID-19 pandemic, change the relative centrality of logics and prompt individuals to engage in incompatible behaviors. We also discuss how consumers manage the sudden and unexpected institutional complexity they face and seek to restore their wellbeing. © The Author(s) 2024
Reflections on the "Ethics Guideline for Using Generative Artificial Intelligence in Scientific Research and Publication Process of Higher Education Institutions"
No full textChronus: Understanding and Securing the Cutting-Edge Industry Solutions to Dram Read Disturbance
No full textErgin, Oguz/0000-0003-2701-3787Read disturbance in modern DRAM is an important robustness (security, safety, and reliability) problem, where repeatedly accessing (hammering) a row of DRAM cells (DRAM row) induces bitflips in other physically nearby DRAM rows. Shrinking technology node size exacerbates DRAM read disturbance over generations. To help mitigate read disturbance, the latest DDR5 specifications (as of April 2024) introduced a new RowHammer mitigation framework, called Per Row Activation Counting (PRAC). PRAC 1) enables the DRAM chip to accurately track row activations by allocating an activation counter per row and 2) provides the DRAM chip with the necessary time window to perform RowHammer-preventive refreshes by introducing a new back-off signal. Unfortunately, no prior work rigorously studies PRAC's security guarantees and overheads. In this paper, we 1) present the first rigorous security, performance, energy, and cost analyses of PRAC and 2) propose Chronus, a new mechanism that addresses PRAC's two major weaknesses. Our analysis shows that PRAC's system performance overhead on benign applications is non-negligible for modern DRAM chips and prohibitively large for future DRAM chips that are more vulnerable to read disturbance. We identify two weaknesses of PRAC that cause these overheads. First, PRAC increases critical DRAM access latency parameters due to the additional time required to increment activation counters. Second, PRAC performs a constant number of preventive refreshes at a time, making it vulnerable to an adversarial access pattern, known as the wave attack, and consequently requiring it to be configured for significantly smaller activation thresholds. To address PRAC's two weaknesses, we propose a new on-DRAM-die RowHammer mitigation mechanism, Chronus. Chronus 1) updates row activation counters concurrently while serving accesses by separating counters from the data and 2) prevents the wave attack by dynamically controlling the number of preventive refreshes performed. Our performance analysis shows that Chronus's system performance overhead is near-zero for modern DRAM chips and very low for future DRAM chips. Chronus outperforms three variants of PRAC and three other state-of-the-art read disturbance solutions. We discuss Chronus's and PRAC's implications for future systems and foreshadow future research directions. To aid future research, we open-source our Chronus implementation at https://github.com/CMU- SAFARI/Chronus.This paper is a significantly extended version of an earlier work presented at DRAMSec 2024 [175]. We thank the anonymous reviewers of DRAMSec 2024 and HPCA 2025 (both main submission and artifact evaluation) for the encouraging feedback. We thank the SAFARI Research Group members for valuable feedback and the stimulating scientific and intellectual environment. We acknowledge the generous gift funding provided by our industrial partners (especially Google, Huawei, Intel, Microsoft, VMware), which has been instrumental in enabling the research we have been conducting on read disturbance in DRAM since 2011 [222]. This work was also in part supported by a Google Security and Privacy Research Award, the Microsoft Swiss Joint Research Center, and the ETH Future Computing Laboratory (EFCL).Huawei; Intel; VMware; Google Security and Privacy Research Award; Microsoft Swiss Joint Research Center; ETH Future Computing Laboratory (EFCL); Google; Microsof
Model-Free Inverse H-Infinity Control for Imitation Learning
No full textThis paper proposes a data-driven model-free inverse reinforcement learning (IRL) algorithm tailored for solving an inverse H∞ control problem. In the problem, both an expert and a learner engage in H∞ control to reject disturbances and the learner’s objective is to imitate the expert’s behavior by reconstructing the expert’s performance function through IRL techniques. Introducing zero-sum game principles, we first formulate a model-based single-loop IRL policy iteration algorithm that includes three key steps: updating the policy, action, and performance function using a new correction formula and the standard inverse optimal control principles. Building upon the model-based approach, we propose a model-free single-loop off-policy IRL algorithm that eliminates the need for initial stabilizing policies and prior knowledge of the dynamics of expert and learner. Also, we provide rigorous proof of convergence, stability, and Nash optimality to guarantee the effectiveness and reliability of the proposed algorithms. Furthermore, we showcase the efficiency of our algorithm through simulations and experiments, highlighting its advantages compared to the existing methods. © 2004-2012 IEEE.National Natural Science Foundation of China, NSFC, (61991404, U22A2049, 62394342); National Natural Science Foundation of China, NSFC; Liaoning Revitalization Talents Program, (XLYC2007135); Liaoning Revitalization Talents Program; 2020 Science and Technology Major Project of Liaoning Province, (2020JH1/10100008); Key Research and Development Program of Liaoning Province, (2023JH26/10200011); Key Research and Development Program of Liaoning Province; Liaoning Liaohe Laboratory, (LLL23ZZ-05-01
The Human Capacity for Measurement With a Unit
No full textMeasurement is about finding structure in a set of objects (or events). It is about associating a set of objects whose structure we wish to understand with a set of formal objects, typically numbers, whose structure we understand. Underlying measurements are the four types of scales (nominal, ordinal, interval, and ratio), which differ in how much information they provide about the objects being measured. These scale types are classified into those that involve a unit of measurement (interval and ratio) and those that do not (nominal and ordinal). In this paper, we make use of this distinction to formulate a hypothesis about the nature of human concepts. We suggest that humans and only humans mentally represent concepts that rely on measurement scales that invoke a unit (i.e. interval and ratio scales). We test this uniqueness claim in the context of social cognition and show that this hypothesis provides a principled account of why certain forms of sociality are only observed in human relations. We highlight the fact that the significance of measurement scales in the study of cognition in general and human cognition in particular is yet to be appreciated. © The Author(s) 2025.Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TUBITA
Comparison of the Efficacy and Safety of Immunomodulator Use in Geriatric and Non-Geriatric Patients With Inflammatory Bowel Disease
No full textTriküspit Valve-in-Valve İşlemi: Biyoprotez Kapak Floroskopide Görünmediğinde Ne Yapmalı? Zorluklar ve Prosedürün Adım Adım Açıklaması
No full textBiyoprotez kalp kapaklarının en büyük dezavantajı orta ve uzun vadede dejenerasyon gelişmesidir. Triküspit kapak replasmanı sonrası biyoprotez dejenerasyonu gelişen hastalarda yeniden ameliyat riskinin yüksek olması nedeniyle perkütan valve in valve (ViV) yaklaşımı tercih edilmektedir. Biyoprotez kapak radyo-opak olmadığında işlemin zorlayıcı yönleri olabilir. Hastanemizde gerçekleştirilen 3 tirküspit ViV olgusunu sunmayı, işlemin adım adım yapılışını ve floroskopide kapak görünmediğinde hizalamanın nasıl gerçekleştirildiğini tarif etmeyi amaçladık. Sağ kalp yetersizliği ile başvuran hastaların triküspit biyoprotez kapaklarında ciddi disfonksiyon görüldü. Ameliyat notları gözden geçirildi ve ViV aplikasyonu kullanılarak kapak boyutları belirlendi. İlk hastada biyoprotez kapak floroskopide açıkça görülüyordu ve kapağı hizalarken zorluk yaşanmadı. Ancak diğer iki hastanın biyoprotez kapakları floroskopide görülmüyordu. Predilatasyon yapıldı ve indentasyon çizgisi referans olarak kullanıldı. Balonla genişletilebilir kapak hizalanırken EKO görüntüleme ve sağ atriyal/ventriküler anjiyogramlar yapıldı. ViV işlemi her 3 vakada da başarılı oldu. Transkateter ViV işlemi triküspit biyoprostetik kapak dejenerasyonu olan hastalar için iyi bir tedavi seçeneğidir. Kapağın radyo-opak olmadığı durumlarda, balon dilatasyonu sırasındaki indentasyon noktasına dikkat edilerek, sağ ventrikülografi ve sağ atriyografiler yapılarak ve EKO kılavuzluğundan faydalanılarak yeni kapağın istenilen şekilde hizalanması gerçekleştirilebilir