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Examining a Science Teacher's Pedagogical Content Knowledge: Interactions among Components through an Alternative Mapping Approach
No full textThis study investigates the interaction of a science teacher's pedagogical content knowledge (PCK) components during the instruction of seventh-grade physics topics-work/energy and simple machines. It aims to explore how these components interconnect and influence instructional practices, particularly in the context of teaching gifted students. The study employed a qualitative research design, using classroom observations as the primary data source. It utilized the Alternative Mapping Approach (AMA), an adaptation of Park and Chen's (2012) mapping-out method, to analyze PCK interactions. Content analysis and the constant comparative method were applied to interpret the data and construct detailed PCK interaction maps. The study yielded four key findings. First, PCK interaction maps are topic-specific and differ in complexity and structure. Second, student-related factors-such as learning difficulties, misconceptions, and characteristics of gifted learners-significantly influenced pedagogical decisions. Third, the teacher's knowledge of instructional strategies played a central role in initiating interactions, while knowledge of learners was crucial in addressing instructional challenges. Lastly, contextual factors, particularly the needs of gifted students, required enrichment activities that demonstrated dynamic interactions between knowledge of curriculum and other PCK components. This study contributes to PCK research by introducing the Alternative Mapping Approach (AMA) as a novel and effective tool for capturing the complexity and sequence of PCK component interactions. It highlights the importance of considering contextual and qualitative dimensions in understanding how PCK is enacted in real classroom settings, particularly in differentiated instruction for gifted learners
Graph-theoretic sensor placement for blade tip timing in multi-mode vibration monitoring: a fast and deterministic alternative to evolutionary algorithms
No full textAccurate reconstruction of blade vibrations is essential in the safe and efficient operation of turbomachinery. Blade Tip Timing (BTT) is a non-contact technique that enables vibration monitoring without requiring physical sensors on blades. However, since each sensor provides only one data point per rotation, BTT is highly under-sampled. This makes sensor placement a critical factor in ensuring accurate signal reconstruction. Previous methods, especially those based on Particle Swarm Optimization (PSO), have attempted to address this challenge. While PSO can explore large solution spaces, it also has several shortcomings: it is computationally expensive, sensitive to parameter settings, and non-deterministic producing different results on each run. These factors limit its usability in real-time and safety-critical applications. In this study, we propose a novel graph-theoretic approach for optimal sensor placement in BTT systems. Candidate sensor angles are modeled as nodes in a weighted graph, and their pairwise compatibility is measured using the condition number of the sensing matrix, which reflects numerical stability. To find the best sensor configuration, a brute-force maximum clique search is applied, ensuring that all possible combinations are evaluated and the most stable set is selected. This method offers several contributions: it is fully deterministic, requires no parameter tuning, and gives the same result every time. It is significantly faster than PSO and easier to interpret, making it suitable for practical use. Results show that it achieves similar or better reconstruction accuracy compared to PSO, especially when the number of sensors is small. Unlike previous black-box optimization methods, our approach offers clear insight into why specific sensor angles are chosen. However, the brute-force nature of the algorithm can become computationally expensive when the number of candidate angles or sensors is large. Future work may focus on improving scalability, adapting the method to real-time applications, and testing it with experimental data from real blades. Overall, this work presents a reliable, interpretable, and efficient alternative to existing sensor placement techniques for BTT, addressing key limitations of earlier methods and laying the foundation for further development in the field
A recombinant full-length VP2-2b-based ELISA for evaluating immunoprotection against canine parvovirus-2: Expression, development and validation
No full textCanine parvovirus-2 remains a major threat to canine health, with maternal antibody interference and limitations of traditional diagnostic methods posing challenges to effective disease control. Maternal-derived antibodies can persist at levels that interfere with the development of active immunity following vaccination. Therefore, accurate detection of existing antibody levels prior to vaccination is essential to ensure induction of protective immunity. Hemagglutination inhibition tests are labor-intensive and highly susceptible to external variability, emphasizing the need for reliable and cost-effective alternatives. In this study, we developed and optimized an indirect ELISA using a full-length, recombinant VP2-2b protein expressed in E. coli to detect CPV-2 antibodies. To our knowledge, this is the first ELISA developed around a soluble full-length CPV-2b protein, with comprehensive optimization and clinical validation. VP2-2b was selected for its unique bidirectional neutralization kinetics, enhancing the diagnostic accuracy of CPV-2 serology. The ELISA demonstrated excellent sensitivity and specificity, effectively distinguishing between seropositive and seronegative samples. A gray zone (OD450 = 0.26–0.30) was defined to represent borderline antibody titers, where retesting is recommended to determine accurate vaccination timing. Optimal assay conditions were established as 7.5 μg antigen coating concentration and 1:300 serum dilution, yielding a high signal-to-noise ratio (SNR) of 5.6. Validation against HI tests showed strong correlation with minimal non-specific binding. This ELISA system provides a reliable and economical alternative to traditional methods, helping overcome the limitations of the HI test in field settings and supporting informed decisions in vaccination planning
THE ROUTLEDGE COMPANION TO COMPARATIVE INTERNATIONAL PLANNING
No full textThis companion provides an overview of a rich field of scholarship and practice, covering key debates around the purpose and value of comparison as a way of generating knowledge and theory. It features examples of comparative studies which explore contemporary issues in planning for sustainable urban and territorial development. Across seven parts, the book explores questions of ‘why’ engage in international comparative planning research; ‘what’ planning aspects might be compared; and ‘how’ comparison might be approached. Through compelling cases of contemporary comparative research on diverse planning topics, including planning systems and governance, planning instruments and law, urban morphology, planning for risk, perspectives on informality, comparative pedagogy, and more, readers will gain a wide appreciation of comparative studies and the current state of the field. The book comprises 37 chapters by 61 contributors from around the world, offering their vital insights into the vibrant and evolving scholarship. The companion will be of interest to educators, academics and researchers, planning practitioners, city and municipal governments, consultants, and advanced students in the fields of city, urban, and regional planning, urban design, human geography, and urban, environmental, and international development studies, interested in comparing and co-learning from global practices and places
On a group under which symmetric Reed–Muller codes are invariant
No full textThe Reed–Muller codes are a family of error-correcting codes that have been widely studied in coding theory. In 2020, Yan and Lin introduced a variant of Reed–Muller codes called symmetric Reed–Muller codes. We investigate linear maps of the automorphism group of symmetric Reed–Muller codes and show that the set of these linear maps forms a subgroup of the general linear group, which is the automorphism group of punctured Reed–Muller codes. We provide a method to determine all the automorphisms in this subgroup explicitly for some special cases
Phenotypic plasticity including drug efflux drives reversible irinotecan resistance in LIM1215 colorectal cancer cells
No full textColorectal cancer (CRC) presents significant therapeutic challenges, particularly due to the development of resistance to standard chemotherapeutic agents such as irinotecan. In this study, we aimed to investigate the molecular and phenotypic mechanisms underlying irinotecan resistance in CRC using the LIM1215 cell line model. Transcriptomic analysis demonstrated that drug withdrawal induced major transcriptional reprogramming, characterized by downregulation of ABC transporters (ABCB1 and ABCG2), extracellular matrix-related genes, and markers of epithelial-to-mesenchymal transition (EMT), alongside reactivation of cell cycle pathways. Drug screening further indicated that resistant cells maintained under irinotecan pressure exhibited a multidrug-resistant phenotype, while withdrawn cells regained sensitivity, particularly to tyrosine kinase inhibitors. Supplementation with the efflux inhibitor Elacridar partially restored drug sensitivity in resistant cells, emphasizing the role of transporter-mediated efflux in maintaining resistance
Pulse sequence analysis-based characterization of corona and surface discharges under DC voltages
No full textPartial discharge (PD) measurement under direct current (DC) stress has been receiving increasing attention due to the increasing prevalence of medium voltage (MVDC) and high voltage (HVDC) systems and cable technologies. Since PD patterns differ significantly under DC voltage from those under alternating current (AC) stress, this work presents a comprehensive investigation of the PD pattern under DC voltage by considering both corona and surface discharge scenarios. Surface discharges were simulated on glass dielectric samples, while corona discharges were built in needle-plane geometry under both positive and negative polarities. Pulse sequence analysis and statistical evaluations of discharge characteristics revealed different behaviors under positive and negative polarities as well as other factors like the level of threshold used to detect PD pulses, the number of pulses used to construct a pattern, noise levels and multisource PDs. The findings emphasize the robustness of various PD patterns under these conditions and the suitability of each pattern for analyzing PD data
Effect of torch path modification on microstructure and mechanical properties in wire arc additive manufacturing of 316L austenitic stainless steel
No full textMechanical anisotropy is a key challenge in wire arc additive manufacturing (WAAM), which is caused by inherent heat transfer conditions and competitive grain growth during solidification. These factors lead to elongated columnar grains oriented toward the substrate, impairing mechanical properties. This study explores a novel torch path strategy to reduce mechanical anisotropy in WAAM-fabricated 316L stainless steel by modifying the conventional torch movement into a forward–backward oscillatory pattern. Two walls were deposited: Norm-316L (conventional unidirectional welding) and FB-316L (oscillatory torch motion). Microstructural analyses were conducted using field emission scanning electron microscopy (FE-SEM) and electron backscatter diffraction (EBSD), alongside mechanical testing. Inverse pole figure (IPF) maps showed dominant columnar grains in Norm-316L, while FB-316L exhibited fewer columnar and more equiaxed grains. Compared to Norm-316L, the FB-316L sample showed a reduction in dominant texture intensity by 42.3%, 65.5%, and 78.2% in the build (BD), transverse (TD), and normal (ND) directions, respectively. Grain boundary maps revealed a transition from predominantly low-angle grain boundaries (LAGBs) in Norm-316L to predominantly high-angle grain boundaries (HAGBs) in FB-316L. Kernel average misorientation (KAM) maps indicated lower local misorientation, reflecting a more homogeneous distribution of dislocations, while grain orientation spread (GOS) analysis revealed reduced intragranular misorientation in FB-316L. Mechanical tests confirmed strong anisotropy in Norm-316L (UTS: 452–529 MPa, El: 28–38.7%, Impact: 81–92 J), while FB-316L exhibited nearly isotropic properties (UTS ≈ 550 MPa, El > 43%, Impact > 96 J)
Visual Mission Scripting for Multi-Agent-Based Simulation of Autonomous Platforms
No full textIn closed-loop simulations, scripting the missions of autonomous agents before scenario execution is challenging. This is partly because of emergent multi-agent behavior, especially for scenarios of long-duration. Moreover, the users of simulation software are usually non-programmers. This makes traditional scripting a difficult tool for programming multiple agents. Existing solutions -such as scripting languages and visual scripting- mainly stem from the game industry where popular game engines provide tools for programming agent behavior for game developers. Closed-loop simulation autonomy requirements differ in the sense that, a certain autonomy alongside a long or complicated scenario should be defined, which requires a higher-level on top of low-level agent autonomy. Reactive and inherently short-sighted agent programming tools based on state-based automata, such as behavior trees and finite state machines, can fall short for the definition of long-term plans. Moreover, these methods require some learning and adaptation effort for non-programmer users or operators. This paper presents a visual agent planning solution based on Business Process Model and Notation (BPMN). Most end-users are relatively familiar with the proposed visual notations in general. Therefore, the method provides human-readable and easy-to-comprehend conditional agent planning capability. The proposed mission programming approach guides the user to build concurrent and synchronized mission plans for implementing tactical behavior. We also discuss some details about the method and argue that the proposed approach can be promising for autonomous platform programming at the mission level