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Most students always lack of experience and perceive difficult regarding problem posing. The study hypothesized that worked examples may have benefits for supporting students' problem posing activities. A quasi-experiment was conducted in the context of a business mathematics course for examining the effects of integrating worked examples into problem posing activities. A total of 107 undergraduate students at a technology university were invited to join this experiment for six weeks. The problem posing activities were carried out in a web-based learning system. The experimental condition receiving worked examples was compared with a control condition regarding the number, orientation and complexity for indicating problem posing performance. To evaluate students' problems as objectively as possible, a Problem-Level-Taxonomy was developed in this study. By the independent sample t-test analysis, the results showed that integrating worked examples into problem posing has a significant skills development effect on posing more orientated and complex problems, particularly for analytical problems referring to a learning concept or a formula. Besides, novice students with none experience in problem posing may benefit from the support of worked examples to improve their problem posing skills. The implications and limitations of this study were also discussed. (Contains 3 tables and 1 figure.)

The purpose of this paper is to develop different guided writing strategies based on media richness theory and further evaluate the effects of these writing strategies on younger students' writing attitudes in terms of motivation, enjoyment and anxiety. A total of 66 sixth-grade elementary students with an average age of twelve were invited to join the experiment for a period of twelve weeks. A repeated-measure one-way ANOVA analysis was utilized to examine the differences among the three strategies including a rich media guided writing strategy, lean media guided writing strategy, and pen-and-paper guided writing strategy. The findings of this study showed the rich media guided writing strategy had higher significant differences than the pen-and-paper guided writing strategy in terms of writing attitudes toward motivation, enjoyment and anxiety. However, there were no significant differences between the rich media guided writing strategy and lean media guided writing strategy in terms of motivation and anxiety. The findings imply that providing a web-based learning environment with high richness media could guide students to write and achieve more positive writing attitudes in terms of motivation, enjoyment and anxiety. (Contains 5 figures and 5 tables.)

Although previous research has demonstrated learning benefits for both instructors and students in the web-based collaborative learning environments, one of them major difficulties is the lack of a practical approach to assist teachers in evaluating the knowledge contribution of learners. A novel method of merging multi-modes of assessment and reward mechanism in a collaborative learning system was examined in this study. The developed system has been applied to a learning activity of a web programming and design course and 102 2nd-year college students from two classes were invited to participate in this research. The system logs and assessment results were analyzed through system use over 6 weeks. The experimental results showed not only could the proposed approach provide instructors with feedback, it could also evaluate and improve learning. In addition, learners could easily and efficiently manage their learning outcomes, share knowledge with one another, reflect on and notify others of learning outcomes and learning status, and engage in high-level reflective practices. (Contains 7 figures and 5 tables.)

Lipids play an important role in the pathogenesis of cardiovascular disease. Changes in lipids of erythrocytes are indicative of the outcome of pathophysiological processes. In the present study, we assessed whether the lipid profiles of erythrocytes from heart failure (HF) patients are informative of their disease risk. The lipidomes of erythrocytes from 10 control subjects and 29 patients at different HF stages were analyzed using liquid chromatography time-of-flight mass spectrometry. The lipid composition of erythrocytes obtained from HF patients was significantly different from that of normal controls. The levels of phosphatidylcholines (PCs), phosphatidylethanolamines (PEs), and sphingomyelins decreased in HF erythrocytes as compared with those of control subjects; however, the levels of lysoPCs, lysoPEs, and ceramides increased in HF erythrocytes. Notably, the oxidized cholesterol 7-ketocholesterol (7KCh) accumulated to higher level in HF erythrocytes than in plasma from the same patients. We further validated our findings with a cohort of 115 subjects of control subjects (n=28) and patients (n=87). Mechanistically, 7KCh promoted reactive oxygen species (ROS) formation in cardiomyocytes; and induced their death, probably through an ATF4-dependent pathway. Our findings suggest that erythrocytic 7KCh can be a risk factor for HF, and is probably implicated in its pathophysiology., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

Purpose: To evaluate visual function after emergent acceleration stress., Methods: Sixteen subjects were enrolled in this study. Human ejection seat trainer was used to induce six times gravitational force in the head-to-toe (z-axis) direction (+6 Gz). Visual performance was evaluated using the visual chart and contrast sensitivity (CS) at indicated times. Ocular reactions were assessed with biomicroscopy and topographic mapping., Results: Temporary visual acuity reduction (0.02 ± 0.05 vs. 0.18 ± 0.08 logMAR visual acuity [VA]; P < 0.05) and ocular reactions were observed after ejection. These reactions included changes in increasing anterior chamber depth (ACD; 3.18 ± 0.29 vs. 4.48 ± 0.32 mm; P < 0.05) and pupillary dilation (PD; 3.56 ± 0.72 vs. 5.64 ± 0.56 mm; P < 0.05). The ACD deepening continued at 15 minutes (4.37 ± 0.26 mm; P < 0.05), and PD persisted at 30 minutes after the gravitational stress (5.42 ± 0.54 mm, P < 0.05). CS decreased significantly at all spatial frequencies immediately after ejection. However, CS returned to the initial range at high spatial frequency by 30 minutes., Conclusions: Emergent acceleration force induces significant ocular responses and visual fluctuation. Prolonged ACD deepening (>15 minutes) and PD (>30 minutes) were noted, but cornea and refraction remain stable. CS at all spatial frequencies revealed remarkable reduction immediately after ejection, and recovered to baseline levels within 30 minutes only at high spatial frequency. Neuroretinal function may involve visual fluctuation after acceleration stress, because visual fluctuation corresponds with the characters of neuroretinal function. However, further studies are necessary.