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When electronic portfolios (e-portfolios) are employed as summative assessments for degree granting programs, it is imperative that graduate students demonstrate their knowledge in the field to showcase learning growth and achievement of the program learning outcomes. This study examined the extent master's degree students in the field of educational technology demonstrated their technological pedagogical content knowledge (TPACK) related elements in their e-portfolio reflection, when they were guided by TPACK framework grounded instruction. Using content analysis technique and open-ended survey responses, the findings show that graduate students were able to demonstrate their interconnected technological pedagogical knowledge in their reflection to justify their competencies. In addition, graduate students had positive reactions to the opportunity to reflect through writing the reflection paper. This study contributes to the eportfolio literature by signifying the importance of providing a discipline-specific framework to guide students' reflection of learning. The TPACK grounded instruction helped graduate students stay focused on their reflection. This study also contributes to the TPACK literature by demonstrating the extent to which graduate students presented their integrated knowledge of TPACK at the end of a program driven to developing students' technology integration expertise. [ABSTRACT FROM AUTHOR]

Attending professional development (PD) on teaching online is becoming popular for teachers in today's K-12 online education. Due to the unique characteristics of the online instructional environments, surveys become the most feasible approach to evaluate the effectiveness of PD programs. However, there is no validated, open-access instrument available to satisfy the needs. Purpose of this study is to conduct construct validity, content validity, concurrent validity, and reliability tests on an open-access instrument for K-12 PD for online teaching. With the exception of a few items that have minor issues on content and construct validity, results show that the survey is, in general, a valid and reliable instrument. Suggestions and potential applications of the instrument are also discussed. [ABSTRACT FROM AUTHOR]

Day-ahead solar irradiance forecasting is carried out using data from a tropicaI environment, Singapore. The peiformance of the weather research and forecasting (WRF) model is evaluated. We explore various combinations of physics configuration setups in the WRF model and propose a setup for the tropical regions. The WRF model is benchmarked using persistence and two seasonal time series models, namely, the exponential smoothing (ETS) and seasonal autoregressive integrated moving average (SARIMA) models. It is shown that the WRF model outpeiforms the SARIMA model and achieves accuracies comparable with persistence and ETS models. Persistence, ETS, and WRF models have relative root mean square errors (rRMSE) of about 55-57%. Furthermore, we find that by combining the forecasting outputs of WRF and ETS models, errors can be reduced to 49%. [ABSTRACT FROM AUTHOR]

Student engagement in science is likely relate to their perceptions of science usefulness. The lack of readily available tools to assess students' perceptions of science usefulness led us to develop the Science Usefulness Survey (SUS). The SUS is publicly available to those seeking to assess students' general perceptions of science usefulness. Our research and development resulted in a validated reliable instrument to assess student perceptions of a range of science issues. We found a number of unique relationships between science usefulness that are relevant for guiding instruction and curriculum choices. We discuss the implications, applications, and directions for future research. [ABSTRACT FROM AUTHOR]

Misconceptions about engineering and science concepts persist among engineering students, and some are resistant event direct instruction. This paper reports on a unique form of computer-based online learning module, designed to help engineering undergraduates learn difficult concepts in the thermal and transport sciences (specifically, heat transfer, mass diffusion, and microfluidics). The design of these modules has been informed by relevant research on cognitive psychology and technology-enhanced learning. Specifically, the modules are based on the prior work of Chi and Slotta, which focus on helping students understand the emergent properties of complex physical systems, thereby providing a means for promoting conceptual change within these challenging domains. The modules were designed and hosted in a Web-base learning management system, where a variety of interactive materials and inquiry prompts were incorporated to help students better understand the concepts and visualize the phenomena. Engineering students' perceptions of compute based online learning are reported along with learning outcomes that resulted from their use of the modules. This was the first study to provide a discipline-based example in engineering education for how to use computer-based online learning and emergent properties of complex systems to help undergraduate engineering students learn difficult concepts. It has implications for (1) designing effective online learning environments to help students learn difficult science and engineering concepts; and (2) developing effective instructional strategies for promoting conceptual change. [ABSTRACT FROM AUTHOR]

Strontium ranelate is a newly approved drug that can reduce the risk of vertebral fracture, which is attributed to its dual function in increasing the bone formation and decreasing the bone resorption. Strontium-containing hydroxyapatite was also demonstrated to stimulate the osteoblast activity and inhibit the osteoclast activity. However, the molecular mechanisms of strontium underlying such beneficial effects were still not fully understood. In this study, we investigated the effects of strontium on the osteogenic differentiation of human mesenchymal stem cells (MSCs) and its related mechanism; its osteogenic potential was also evaluated using a calvarial defect model in rats. We found that strontium could enhance the osteogenic differentiation of the MSCs, with upregulated extracellular matrix (ECM) gene expression and activated Wnt/β-catenin pathway. After transplanting the collagen-strontium-substituted hydroxyapatite scaffold into the bone defect region, histology and computed tomography scanning revealed that in vivo bone formation was significantly enhanced; the quantity of mature and remodeled bone substantially increased and ECM accumulated. Interestingly, strontium induced an increase of β-catenin expression in newly formed bone area. In this study, we showed for the first time that strontium could stimulate the β-catenin expression in vitro and in vivo, which might contribute to the enhanced osteogenic differentiation of MSCs and in vivo bone formation. STEM CELLS 2011;29:981-991 [ABSTRACT FROM AUTHOR]

This research examines factors that influenced teachers' decisions to participate in professional development activities and, subsequently, to implement ideas gained through their participation. Twenty-four teachers who were employed by an urban school district shared their perceptions regarding the content, context, and process of a districtwide professional development initiative focused on digital age literacy skills. Results emphasize how factors that are internal and external to the teachers influenced their decisions to adopt and implement initiative-promoted strategies. Teachers' perceptions of the sustainability of new classroom practices, as gained through the initiative, are also discussed. [ABSTRACT FROM AUTHOR]

In this study, diamond-like carbon (DLC) films were deposited on biomedical AISI316L stainless steel by hybrid plasma source ion implantation (PSII) and plasma-enhanced chemical vapour deposition (PECVD). Potentiodynamic polarization tests and Electrochemical Impedance Spectroscopy (EIS) have been employed to investigate the corrosion performance of different DLC films in Tyrode's simulated body fluid (pH = 7.4). The corrosion resistance of the DLC films by PECVD deteriorated rapidly after 24 h of immersion, but those made by hybrid PSII and PECVD offered more effective barrier for AISI316L stainless steel during 72 h of immersion. The test results demonstrated that the DLC film by hybrid PSII and PECVD possessed less corrosion current density, greater corrosion resistance, and more positive breakdown potential in simulated body fluid. [ABSTRACT FROM AUTHOR]

An increasing number of T-cell epitopes derived from various tumor-associated antigens have been reported, and they proved to play significant roles for tumor rejection both in vivo and in vitro. Over 85% of Ewing's sarcoma family of tumors (ESFTs) express tumor-specific chimeric protein EWS/FLI-1, making it an attractive target for therapeutic cytotoxic T-lymphocyte responses. Here, we identified a novel peptide epitope derived from the EWS/FLI-1 protein and demonstrated that effectors induced by the peptide could specifically secrete IFN-γ and lyse the tumor cell line of EWS/FLI-1-positive and HLA-matched cells. In addition, mice treated with dendritic cells pulsed with the EWS/FLI-1 epitope were able to reject a lethal tumor inoculation of the Ewing's sarcoma A673 cells. Therefore, these data provide evidence for the use of the EWS/FLI-l peptide epitope in T cell-based immunotherapeutic concepts against Ewing's sarcoma cell in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Fullerene skeleton modification has been investigated through selective cleavage of the fullerene carbon-carbon bonds under mild conditions. Several cage-opened fullerene derivatives including three [59]fullerenones with an 18-membered-ring orifice and one [59]fullerenone with a 19-membered-ring orifice have been prepared starting from the fullerene mixed peroxide 1, C60(OOtBu)6. The prepositioned tertbutyl peroxy groups in 1 serve as excellent oxygen sources for formation of hydroxyl and carbonyl groups. The cage-opening reactions were initiated by photoinduced homolysis of the tBu-O bond, followed by sequential ring expansion steps. A key step of the ring expansion reactions is the oxidation of adjacent fullerene hydroxyl and amino groups by diacetoxyliodobenzene (DIB). Aminolysis of a cage-opened fullerene derivative containing an anhydride moiety resulted in multiple bond cleavage in one step. A domino mechanism was proposed for this reaction. Decarboxylation led to elimination of one carbon atom from the C60 cage and formation of [59]fullerenones. The cage-opened [59]fullerenones were found to encapsulate water under mild conditions. All compounds were characterized by spectroscopic data. Single-crystal structures were also obtained for five skeleton-modified derivatives including two water-encapsulated fulleroids. [ABSTRACT FROM AUTHOR]

Although multiple natural products are potent ligands for the diacylglycerol binding C1 domain of protein kinase C (PKC), RasGRP, and related targets, the high conservation of C1 domains has impeded the development of selective ligands. We characterized here a diacylglycerol-lactone, 130C037, emerging from a combinatorial chemical synthetic strategy, which showed substantial selectivity. 130C037 gave shallow binding curves for PKC isoforms α, β, γ, δ, and ε, with apparent Ki values ranging from 340 nM for PKCα to 29 nM for PKCε. When binding to isolated C1 domains of PKCα and -δ, 130C037 showed good affinity (Ki = 1.78 nM) only for δC1b, whereas phorbol 12,13-dibutyrate showed affinities within 10-fold for all. In LNCaP cells, 130C037 likewise selectively induced membrane translocation of δC1b. 130C037 bound intact RasGRP1 and RasGRP3 with Ki values of 3.5 and 3.8 nM, respectively, reflecting 8- and 90-fold selectivity relative to PKCε and PKCα. By Western blot of Chinese hamster ovary cells, 130C037 selectively induced loss from the cytosol of RasGRP3 (ED50 = 286 nM), partial reduction of PKCε (ED50 > 10 µM), and no effect on PKCα. As determined by confocal microscopy in LNCaP cells, 130C037 caused rapid translocation of RasGRP3, limited slow translocation of PKCε, and no translocation of PKCα. Finally, 130C037 induced Erk phosphorylation in HEK-293 cells ectopically expressing RasGRP3 but not in control cells, whereas phorbol ester induced phosphorylation in both. The properties of 130C037 provide strong proof of principle for the feasibility of developing ligands with selectivity among C1 domain-containing therapeutic targets. [ABSTRACT FROM AUTHOR]

Homeostasis of bone metabolism is regulated by the central nervous system, and mood disorders such as anxiety are associated with bone metabolism abnormalities, yet our understanding of the central neural circuits regulating bone metabolism is limited. Here, we demonstrate that chronic stress in crewmembers resulted in decreased bone density and elevated anxiety in an isolated habitat mimicking a space station. We then used a mouse model to demonstrate that GABAergic neural circuitry in the ventromedial hypothalamus (VMH) mediates chronic stress-induced bone loss. We show that GABAergic inputs in the dorsomedial VMH arise from a specific group of somatostatin neurons in the posterior region of the bed nucleus of the stria terminalis, which is indispensable for stress-induced bone loss and is able to trigger bone loss in the absence of stressors. In addition, the sympathetic system and glutamatergic neurons in the nucleus tractus solitarius were employed to regulate stress-induced bone loss. Our study has therefore identified the central neural mechanism by which chronic stress-induced mood disorders, such as anxiety, influence bone metabolism. [ABSTRACT FROM AUTHOR]