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This study proposed a computerized inquiry-stage-dependent argumentation assistance and investigated whether this can help improve elementary students' performance in science processes and the construction of quality arguments. Various argumentation assistances were developed and incorporated into each stage of scientific inquiry in a computer-supported scientific inquiry system. A nonequivalent quasi-experimental design was adopted to evaluate the effectiveness of this approach. Two intact sixth grade classes (N = 55) participated in this study, and each student used a tablet computer to accomplish the designated inquiry activities. One class of students was arranged to use the stage-dependent argumentation assistance, and the other used a generic text-based interface. The findings indicate that students who used the stage-dependent argumentation assistance could acquire significantly better science process and argument construction skills than those using the generic text-based interface.

This research investigated how differently elementary school students participate in synchronous online collaborative learning by analysing their discussions with their partners. Two hundred and seventy-eight Taiwanese students, ranging in age from 11 to 12 years old, were involved in this study. The students were randomly arranged within-class into three-member groups. Each group used a collaborative learning system to discuss and accomplish a group assignment (creating a shared concept map). The textual discussions by each individual student were collected, categorised and accumulated. Cluster analysis was adopted to statistically classify students based on their discussion characteristics. We found that a student, while participating in online collaboration and communication, exhibited a distinct style: "less contributing," "coordination emphasising," "communicative" or "task-oriented." In addition, students exhibiting the "task-oriented" pattern and students predominantly showing "communicative" behaviours were found to have better learning performance and retain more knowledge than students observed to be "coordination emphasising" or "less contributing" within group collaboration. (Contains 3 tables and 2 figures.)

This study incorporates the 5E learning cycle strategy to design and develop Sharable Content Object Reference Model-conformant materials for elementary science education. The 5E learning cycle that supports the constructivist approach has been widely applied in science education. The strategy consists of five phases: engagement, exploration, explanation, elaboration and evaluation. It has potential value for creating effective science e-learning materials. This study implemented the participatory design (PD) method to investigate the possibility of applying the 5E model to science e-learning materials. PD is an approach that understands "knowledge by doing" and focuses on collaborating with the intended users rather than designing "for" them. In this study, researchers, designers and elementary science teachers cooperated at all stages of the design process (including explanation, analysis and decision making). The issues to be dealt with in this study included instructional designs based on the 5E model, techniques or specifications of e-learning, learning objects, metadata and procedures. The results of this study provided concrete recommendations for how to incorporate the 5E learning cycle and how to develop effective e-learning materials for elementary science instruction.

Directional growth effect on magneto-mechanical properties of Fe81Al19 alloy is studied. The ideal model of heat flux for directional solidification (DS) technique is proposed, and the tuned A/L (the ratio of cross-sectional area and length for the ingot) and ΔT (temperature difference) are adopted to increase heat flux (q). The experimental result shows that the increase of q effectively promotes the degree of (011)[100] Goss texture and therefore helps to form an oriented stripe domain structure. Large λ100 of 93.8 ppm attained for this optimized Fe81Al19 alloy prepared by DS method is very close to that of the Fe81Al19 single crystal (95.0 ppm). For the optimized DS prepared Fe81Al19 alloy, high magnetostriction sensitivity (dλ/dH) of 0.45 ppm/Oe leads to huge ΔEs/E0 of ∼10% and attractive ΔE/E0 of 8.2% at small H = 0.25 kOe. The above remarkable magneto-mechanical properties, low cost of Fe81Al19, and simple process of DS favor for applications. This work proposes an ideal model to emphasize the importance of heat flux in DS, and experimentally attains the remarkable magneto-mechanical properties for Fe81Al19 alloy prepared by DS. [ABSTRACT FROM AUTHOR]

Traditional NdFeB sintered magnets with coercivity larger than 20 kOe, called super-high (SH) level, usually contains considerable amount of high-cost heavy rare earth (HRE), such as Dy or Tb. In this work, high coercivity of 21.4 kOe, which corresponds to SH level, is achieved for HRE-free NdFeB magnet by doping with Ce85Al15 (CeAl) alloy and grain boundary diffusion (GBD) with Pr70Cu15Al15 (PrCuAl) alloy powders, where Ce/RE ratio is about 15% within the magnet. After GBD treatment with PrCuAl on Ce-containing NdFeB magnets, the formation of Pr-containing shell at 2:14:1 grain surface can increase the local magnetic anisotropy filed and therefore enhance the coercivity. Most of Cu and Al, and parts of Ce and Pr appear at grain boundary and triple junction, which can reduce the magnetization of grain boundary phase, strengthen the decoupling effect between grains and thus contribute to high coercivity. This study provides a cost-effective way to obtain high coercivity for HRE-free NdFeB sintered magnet via doping Ce85Al15 and then GBD with Pr70Cu15Al15. [ABSTRACT FROM AUTHOR]

This study examined the influence of various conflict management mechanisms embedded into computer-supported collaborative concept mapping systems on the behaviour and learning of elementary students. Four conflict management mechanisms were compared: an assign design, in which the mapping control was designated to a particular group member; a rotate design, in which the mapping control was rotated among the group members; a give design, in which the child with mapping control could relinquish control to another group member; and an open design, in which every group member simultaneously had mapping control. Ninety-six fifth and sixth grade Taiwanese students participated in this study. They were arranged into assign, rotate, give, or open three-member groups to generate collaboratively shared concept maps. Student interactions, attitudes, and achievement were analysed. The results suggest that each conflict management mechanism has a different effect on the elementary students.

Objective: This study aimed to elucidate whether molecular signalling involved in upper airway remodelling is enhanced in patients with obstructive sleep apnoea. Method: Twenty patients with mild obstructive sleep apnoea (control group) and 40 patients with moderate to severe obstructive sleep apnoea (obstructive sleep apnoea group) who desired uvulopalatopharyngoplasty were recruited for the study. After uvulopalatopharyngoplasty, surgical specimens of the uvula were subjected to haematoxylin and eosin, Masson's trichrome and immunohistochemical staining. Western blot and reverse transcriptase-polymerase chain reaction were used to evaluate the protein and messenger RNA expressions. Results: The obstructive sleep apnoea group showed more severe inflammation, increased collagen deposition and higher immunohistochemical staining intensity for TGF-ß and MMP-9 as well as higher protein and messenger RNA expression of MMP-9, VEGF, TGF-ß, p38 MAPK, SMAD 2/3, AKT and JNK in the uvula than control group. Conclusion: Patients with obstructive sleep apnoea demonstrated more severe inflammation, increased airway remodelling, and increased protein and messenger RNA expression of pro-inflammatory and pro-fibrotic cytokines in the uvula than control participants. [ABSTRACT FROM AUTHOR]

Magnetic properties’ modification and coercivity enhancement of NdFeB sintered magnets prepared by the dual-alloy (DA) sintering together with grain boundary diffusion (GBD) treatment are demonstrated. For the original NdFeB magnet, (BH)max of 51.4 MGOe and ${_{i}}H_{\mathrm {c}}$ of 14.9 kOe are obtained. For the magnet made with the same composition as the former but doped with Ce85Al15 (CeAl) powders, magnetic isolation due to the distribution of Ce and Al at GB increases the coercivity effectively, yet few Ce entering into grain interior decreases $B_{\mathrm {r}}$ , (BH)max, and Curie temperature slightly. In addition, the coercivity of the above magnets can be further enhanced to 22.7–25.1 kOe by GBD with different amounts of Tb70Cu30 (TbCu) powders. The clear core–shell structure, which consists of (Nd, Tb)2Fe14B phase with higher magnetocrystalline anisotropy field ($H_{\mathrm {A}}$) as the shell and Nd2Fe14B phase as the core, is observed. CeAl helps to form a continuous and smooth GB. The diffusion source of TbCu could infiltrate into the magnet along such smooth GB and form a homogeneous core–shell structure. As a result, coercivity is remarkably enhanced from 14.9 kOe for DA sintered magnet with 2 wt% CeAl to 25.1 kOe for the magnet GBD with TbCu. Most importantly, various levels of NdFeB magnets, such as 52M, 35–50SH, and 45UH, could be easily attained by modifying the amounts of CeAl for DA sintered magnets and/or GBD with TbCu powders. [ABSTRACT FROM AUTHOR]

Objectives: Osteoarthritis (OA) is a common degenerative joint disease, and total knee replacement (TKR) is a successful surgical intervention for knee OA treatment. However, the risks of mortality and major cardiovascular events (MACEs) in patients receiving TKR remain unclear. This study investigated the risks of mortality and MACEs in knee OA patients who received TKR.Methods: For this population-based cohort study, the Longitudinal Health Insurance Database 2000 was used. Two million individuals with knee OA defined by ICD-9-CM codes who received physical therapy between 1999 and 2017 were selected. For propensity score matching (PSM), we considered the year of knee OA diagnosis, demographics, comorbidities, co-medications, and knee OA-related hyaluronic acid or physical therapy at baseline. After PSM, regression analyses were performed to assess the association of mortality or MACEs with TKR and non-TKR individuals.Results: We identified patients (n = 189,708) with a new diagnosis of knee OA between 2000 and 2017. In total, 10,314 propensity-score-paired TKR and non-TKR individuals were selected. The PSM cohort algorithm revealed that the risk of mortality or MACEs was lower in the TKR group (adjusted hazard ratio: 0.791; 95% confidence interval: 0.755-0.830) than in the non-TKR group.Conclusions: Patients with knee OA who received TKR had decreased risks of mortality and MACEs than those who did not receive TKR. Moreover, the TKR group received a reduced dosage of nonsteroidal anti-inflammatory drugs at the 1-year follow-up. [ABSTRACT FROM AUTHOR]

In drainage and sewerage systems, vertical dropshafts are commonly used to convey water flow from high to low elevations. When the underground tunnel is surcharged, the lower part of the shaft is submerged. The impact of falling water on the free surface in the dropshaft entrains a vast amount of air, leading to the transport or entrapment of air in the tunnel, causing undesirable effects such as the reduction in flow conveyance capacity or air blowback. In this study, a comprehensive series of experiments was performed to study the influence of flow variables on the flow regimes in a submerged dropshaft connected to a horizontal tunnel. The air-water flow in the dropshaft was recorded using high-speed imaging, with air concentration and high-frequency pressure measurements. The experiments showed that the flow in the dropshaft-tunnel system can be classified into four regimes: (I) bubbly column flow, (II) rising slugs, (III) instability and surging, and (IV) net air transport in the tunnel, based on the dropshaft Froude number and the ratio of dropshaft diameter to tunnel diameter. [ABSTRACT FROM AUTHOR]