Analysis of peer-scaffolding patterns in four phases of problem-solving in web-based instruction

2008Various peer-scaffoldings in problem-solving have been studied as effective learning strategies in web‐based instruction and on‐line discussion. The web-based environment provides a medium for sharing knowledge and resources, which help learners engage in problem-solving and interactive learning. Learners, however, easily feel isolated in web-based environments because of the tremendous amount of resources and visual information that are easily available. In this regard, it is important to seriously consider peer-scaffolding strategies as effective problem-solving strategies. The purpose of the present study is to find patterns of peerscaffolding that constitute effective problem-solving strategies in web-based instruction. Six participants registered in the major leader training program at the National Academy Educational Administrators voluntarily participated in this experiment as part of their coursework. All participants provided their scaffoldings in on-line casual discussions. To collect data from peer group problem-solving interactions in collaborative activities among the six participations, their discourses content was analyzed to nvestigate patterns of peer-scaffolding. The results of this study were as follows: First, the results showed statistically non‐significant differences in peer-scaffoldings among three dimensions: it showed the highest proportion of peer-scaffoldings in the content dimension, followed by the affection dimension, and finally the strategy dimension. Second, comparing the eight types of scaffolding, the offering praise scaffolding was related to the most important scaffoldings for making peers cooperate with each other while they solve problems. Third, considering patterns of peer-scaffolding in the strategy dimension, the maintaining direction scaffolding represents a higher proportion of the understanding phase than the assigning role-taking scaffolding. Fourth, considering patterns of peer-scaffolding in the content dimension, the offering cue scaffolding represents a higher proportion of the solving phase than the other three peer-scaffoldings. Finally, considering patterns of peer-scaffolding in the affection dimension, the inviting participation scaffolding represents a higher proportion of the understanding phase than the offering praise scaffolding. After reviewing phases, the offering praise scaffolding represented a higher proportion than the inviting participation scaffolding

A theoretical review and new directions for designing hybrid learning spaces with web2.0 technologies

2011Learning spaces can have a significant impact on learning. The emergence of virtual space with information technology has transformed the spatial design and organization of the learning spaces. Embodied web2.0 technologies, which empower learners and allow learners collaboration, sharing, and participation between asynchronous and synchronous, have been increasingly changing the way of learning and extending the learning spaces. In spite, an important piece of restructuring learning spaces with web2.0 is not concerned. The purpose of this study is to conceptualize comprehensive constructs for understanding the learning spaces and explore the learning technologist's roles for designing learning spaces with web2.0 technologies through a hybrid approach. Some suggestions for the learning technologists when they design for hybrid learning spaces with web2.0 are as follows: Utilization of affordance-based design through a hybrid approach; Application of self-directed learning strategies in hybrid learning spaces; Integration of Net gen-based design with content strategies; Focusing of designing space for learning itsel

Effects of Cognitive Load Reduction Strategies and Prior Knowledge Levels on Comprehension of Speed Simulation, Cognitive Load, and Learning Efficiency for Fifth Grade Elementary Students

2007The purpose of this study was to investigate how cognitive load reduction strategies and learners' prior knowledge affect on comprehension of speed simulation, cognitive load, and learning efficiency. It was randomly sampled 77 participants among fifth grade students of an elementary school in Seoul city, Korea. They were divided into two groups of prior knowledge (higher and lower) by two different treatment groups (visual worked-example simulation group, visual-auditory worked-example simulation group). Dependent variables were comprehension of speed simulation, cognitive load, and learning efficiency. Results showed that visual-auditory worked-example simulation group was more efficient on comprehension of speed simulation than visual worked-example simulation group, regardless of learners prior knowledge level, so that less cognitive load led to higher level of comprehension

Wearable, Ultrawide-Range, and Bending-Insensitive Pressure Sensor Based on Carbon Nanotube Network-Coated Porous Elastomer Sponges for Human Interface and Healthcare Devices

Flexible and wearable pressure sensors have attracted a tremendous amount of attention due to their wider applications in human interfaces and healthcare monitoring. However, achieving accurate pressure detection and stability against external stimuli (in particular, bending deformation) over a wide range of pressures from tactile to body weight levels is a great challenge. Here, we introduce an ultrawide-range, bending-insensitive, and flexible pressure sensor based on a carbon nanotube (CNT) network-coated thin porous elastomer sponge for use in human interface devices. The integration of the CNT networks into three-dimensional microporous elastomers provides high deformability and a large change in contact between the conductive CNT networks due to the presence of micropores, thereby improving the sensitivity compared with that obtained using CNT-embedded solid elastomers. As electrical pathways are continuously generated up to high compressive strain (∼80%), the pressure sensor shows an ultrawide pressure sensing range (10 Pa to 1.2 MPa) while maintaining favorable sensitivity (0.01–0.02 kPa–1) and linearity (R2 ∼ 0.98). Also, the pressure sensor exhibits excellent electromechanical stability and insensitivity to bending-induced deformations. Finally, we demonstrate that the pressure sensor can be applied in a flexible piano pad as an entertainment human interface device and a flexible foot insole as a wearable healthcare and gait monitoring device

Toll-Like Receptor 4 Decoy, TOY, Attenuates Gram-Negative Bacterial Sepsis

Lipopolysaccharide (LPS), the Gram-negative bacterial outer membrane glycolipid, induces sepsis through its interaction with myeloid differentiation protein-2 (MD-2) and Toll-like receptor 4 (TLR4). To block interaction between LPS/MD-2 complex and TLR4, we designed and generated soluble fusion proteins capable of binding MD-2, dubbed TLR4 decoy receptor (TOY) using ‘the Hybrid leucine-rich repeats (LRR) technique’. TOY contains the MD-2 binding ectodomain of TLR4, the LRR motif of hagfish variable lymphocyte receptor (VLR), and the Fc domain of IgG1 to make it soluble, productive, and functional. TOY exhibited strong binding to MD-2, but not to the extracellular matrix (ECM), resulting in a favorable pharmacokinetic profile in vivo. TOY significantly extended the lifespan, when administered in either preventive or therapeutic manners, in both the LPS- and cecal ligation/puncture-induced sepsis models in mice. TOY markedly attenuated LPS-triggered NF-κB activation, secretion of proinflammatory cytokines, and thrombus formation in multiple organs. Taken together, the targeting strategy for sequestration of LPS/MD-2 complex using the decoy receptor TOY is effective in treating LPS- and bacteria-induced sepsis; furthermore, the strategy used in TOY development can be applied to the generation of other novel decoy receptor proteins

Cordycepin induces human lung cancer cell apoptosis by inhibiting nitric oxide mediated ERK/Slug signaling pathway

Nitric oxide (NO) is an important signaling molecule and a component of the inflammatory cascade. Besides, it is also involved in tumorigenesis. Aberrant upregulation and activation of the ERK cascade by NO often leads to tumor cell development. However, the role of ERK inactivation induced by the negative regulation of NO during apoptosis is not completely understood. In this study, treatment of A549 and PC9 human lung adenocarcinoma cell lines with cordycepin led to a reduction in their viability. Analysis of the effect of cordycepin treatment on ERK/Slug signaling activity in the A549 cell line revealed that LPS-induced inflammatory microenvironments could stimulate the expression of TNF-α, CCL5, IL-1β, IL-6, IL-8 and upregulate NO, phospho-ERK (p-ERK), and Slug expression. In addition, constitutive expression of NO was observed. Cordycepin inhibited LPS-induced stimulation of iNOS, NO, p-ERK, and Slug expression. L-NAME, an inhibitor of NOS, inhibited p-ERK and Slug expression. It was also found that cordycepin-mediated inhibition of ERK downregulated Slug, whereas overexpression of ERK led to an upregulation of Slug levels in the cordycepin-treated A549 cells. Inhibition of Slug by siRNA induced Bax and caspase-3, leading to cordycepin-induced apoptosis. Cordycepin-mediated inhibition of ERK led to a reduction in phospho-GSK3β (p-GSK3β) and Slug levels, whereas LiCl, an inhibitor of GSK3β, upregulated p-GSK3β and Slug. Overall, the results obtained indicate that cordycepin inhibits the ERK/Slug signaling pathway through the activation of GSK3β which, in turn, upregulates Bax, leading to apoptosis of the lung cancer cells

Toxic leukoencephalopathy with axonal spheroids caused by chemotherapeutic drugs other than methotrexate

Background The objective of this report is to share the clinicopathological features of chemotherapy-induced toxic leukoencephalopathy, which is a rare and under-recognized disease, clinically characterized by rapidly progressive cognitive loss that often leads to sudden death. Case presentation A 64-year-old woman and a 63-year-old man, who had both suffered from a rapid deterioration of consciousness, were autopsied under the clinical impressions of either the central nervous system graft versus host disease (CNS-GVHD), infectious encephalitis, or autoimmune encephalitis. Both patients had been treated with multiple chemotherapy regimens, including adriamycin, cytarabine arabinoside, daunorubicin, fludarabine, azacitidine, and allogeneic peripheral blood stem cell transplantation to treat hematological malignancies (acute myelogenous leukemia and myelodysplastic syndrome). Neuropathological findings at autopsy revealed rarefaction and vacuolar changes of the white matter with axonal spheroids, reactive gliosis, and foamy macrophage infiltration, predominantly in the visual pathways of the occipital and temporal lobes. Damaged axons exhibited immunoreactivity to beta-amyloid, consistent with axonopathy. However, there was no lymphocyte infiltration that suggested CNS-GVHD or any type of encephalitis. Conclusion The neuropathology found in the presented cases had the characteristic features of toxic leukoencephalopathy (chemobrain). Our cases showed that toxic leukoencephalopathy can also be caused by chemotherapy drugs other than methotrexate.This research was supported by a fund (2021-ER1001-01) by the Research of Korea Disease Control and Prevention Agency. The role of the funder is financial support for the operation of the brain bank of Seoul National University Hospital and the operation of the brain donation program for the research

Metronidazole-induced encephalopathy in a patient with infectious colitis: a case report

<p>Abstract</p> <p>Introduction</p> <p>Encephalopathy is a rare disease caused by adverse effects of antibiotic drugs such as metronidazole. The incidence of metronidazole-induced encephalopathy is unknown, although several previous studies have addressed metronidazole neurotoxicity. Here, we report the case of a patient with reversible cerebellar dysfunction on magnetic resonance imaging, induced by prolonged administration of metronidazole for the treatment of infectious colitis.</p> <p>Case presentation</p> <p>A 71-year-old Asian man, admitted to our hospital with hematochezia, underwent Hartmann's operation for the treatment of colorectal cancer three years ago. He was diagnosed with an infectious colitis by colonoscopy. After taking metronidazole, he showed drowsiness and slow response to verbal commands. Brain magnetic resonance imaging showed obvious bilateral symmetric hyperintensities within his dentate nucleus, tectal region of the cerebellum, and splenium of corpus callosum in T2-weighted images and fluid attenuated inversion recovery images. Our patient's clinical presentation and magnetic resonance images were thought to be most consistent with metronidazole toxicity. Therefore, we discontinued metronidazole, and his cerebellar syndrome resolved. Follow-up magnetic resonance imaging examinations showed complete resolution of previously noted signal changes.</p> <p>Conclusion</p> <p>Metronidazole may produce neurologic side effects such as cerebellar syndrome, and encephalopathy in rare cases. We show that metronidazole-induced encephalopathy can be reversed after cessation of the drug. Consequently, careful consideration should be given to patients presenting with complaints of neurologic disorder after the initiation of metronidazole therapy.</p

Atopic Dermatitis-Like Skin Lesions Reduced by Topical Application and Intraperitoneal Injection of Hirsutenone in NC/Nga Mice

Atopic dermatitis (AD) is a common inflammatory skin disease. The increasing prevalence and severity of AD have prompted the developments of safer, more effective drugs. Although topical corticosteroids have been used as first line therapy for AD, their potential side effects limit their clinical applications. To investigate the effect of hirsutenone (HIR), a diarylheptanoid compound, on AD-like skin lesions and other factors related to immune response is the aim of this paper Th2-related cytokines (IL-4, IL-5, IL-13), eosinophil, IgE inflammatory factors (COX-2, iNOS) levels were reduced in blood, lymphocytes, and tissue after HIR treatment. These results suggest that HIR might be an effective treatment for AD