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When the goal of group activities is to support long-term learning, the task of designing well-thought-out collaborative learning (CL) scenarios is an important key to success. To help students adequately acquire and develop their knowledge and skills, a teacher can plan a scenario that increases the probability for learning to occur. Such a scenario defines pedagogically sound structures that prevent off-task behavior and engage students in more meaningful interactions. The main difficulty in designing effective CL scenarios is transforming the teacher's intentions into elements that constitute the learning scenario. This problem is frequently observed when novice teachers attempt to improve the quality of learning and instruction by blending collaborative activities with individual activities without careful planning. With the goal of helping teachers in planning collaborative scenarios, we have developed an intelligent authoring tool referred to as CHOCOLATO using Semantic Web technologies (e.g. ontologies) in order to represent knowledge about different pedagogies and practices related to collaboration. Through the use of this knowledge, CHOCOLATO can provide intelligent guidance that helps teachers to create theory-based CL scenarios which has proven to be effective in a variety of situations. We evaluated it by conducting two experiments. We were interested in verifying whether the recommendations given by CHOCOLATO help novice teachers to design pedagogically sound CL activities, and if these activities help students to learn collaboratively in real classroom settings. The first experiment had the participation of 58 pre-service teachers that created CL scenarios with and without our authoring tool and the second experiment was carried out in a Brazilian public school together with 218 students. The results suggest that the guidance provided by CHOCOLATO do help novice teachers plan, understand and share CL scenarios more easily. They also suggest that the continuous utilization of well-designed theory-based CL activities create favorable conditions for students (particularly less knowledgeable ones) to improve their overall performance throughout the school year. (Contains 11 figures.)

During the fetal period, oxygenated blood from the placenta flows through the umbilical vein (UV), portal sinus, ductus venosus (DV), and inferior vena cava (IVC) to the heart. This venous route varies regionally in many aspects. Herein, we sought to characterize the venous route's morphological features and regional differences during embryonic and early-fetal periods. Twenty-nine specimens were selected for high-resolution digitized imaging; 18 embryos were chosen for histological analysis. The venous route showed a primitive, large, S-shaped curved morphology with regional narrowing and dilation at Carnegie stage (CS) 15. Regional differences in vessel-wall differentiation became apparent from approximately CS20. The vessel wall was poorly developed in most DV parts; local vessel-wall thickness at the inlet was first detected at CS20. The lumen of the venous route changed from a nonuniform shape to a relatively round and uniform morphology after CS21. During the early-fetal period, two large bends were observed around the passage of the umbilical ring and at the inlet of the liver. The length ratio of the extrahepatic UV to the total venous route increased. The sectional area gradually increased during embryonic development, whereas differences in sectional area between the DV, UV, and IVC became more pronounced in the early-fetal period. Furthermore, differences in the sectional area between the narrowest part of the DV and other hepatic veins and the transverse sinus became more pronounced. In summary, the present study described morphological, morphometric, and histological changes in the venous route throughout embryonic and early-fetal development, clarifying regional characteristics., (© 2024 American Association for Anatomy.)