37 research outputs found
Getting the point: tracing worked examples enhances learning
Embodied cognition perspectives suggest that pointing and tracing with the index finger may support learning, with basic laboratory research indicating such gestures have considerable effects on information processing in working memory. The present thesis examined whether tracing worked examples could enhance learning through decreased intrinsic cognitive load. In Experiment 1, 56 Year 6 students (mean age = 11.20, SD = .44) were presented with either tracing or no-tracing instructions on parallel lines relationships. The tracing group solved more acquisition phase practice questions and made fewer test phase errors, but otherwise test results were limited by ceiling effects. 42 Year 5 students (mean age = 10.50, SD = .51) were recruited in Experiment 2 to better align the materials with students’ knowledge levels. The tracing group outperformed the non-tracing group at the test and reported lower levels of test difficulty, interpreted as lower levels of intrinsic cognitive load. Experiment 3 recruited 52 Year 6 and Year 7 students (mean age = 12.04, SD = .59) presented with materials on angle relationships of a triangle; the tracing effect was replicated on test scores and errors, but not test difficulty. Experiment 4 used the parallel lines materials to test hypothesized gradients across experimental conditions with 72 Year 5 students (mean age = 9.94, SD = .33), predicting the tracing on the paper group would outperform the tracing above the paper group, who in turn would outperform the non-tracing group. The hypothesized gradient was established across practice questions correctly answered, practice question errors, test questions correctly answered, test question time to solution, and test difficulty self-reports. The results establish that incorporating the haptic input into worked example-based instruction design enhances the worked example effect and that tracing worked examples is a natural, simple yet effective way to enhance novices’ mathematics learning
Recommended from our members
Rapid (<5 min) identification of pathogen in human blood by electrokinetic concentration and surface-enhanced Raman spectroscopy.
This study reports a novel microfluidic platform for rapid and long-ranged concentration of rare-pathogen from human blood for subsequent on-chip surface-enhanced Raman spectroscopy (SERS) identification/discrimination of bacteria based on their detected fingerprints. Using a hybrid electrokinetic mechanism, bacteria can be concentrated at the stagnation area on the SERS-active roughened electrode, while blood cells were excluded away from this region at the center of concentric circular electrodes. This electrokinetic approach performs isolation and concentration of bacteria in about three minutes; the density factor is increased approximately a thousand fold in a local area of ~5000 μm(2) from a low bacteria concentration of 5 × 10(3) CFU/ml. Besides, three genera of bacteria, S. aureus, E. coli, and P. aeruginosa that are found in most of the isolated infections in bacteremia were successfully identified in less than one minute on-chip without the use of any antibody/chemical immobilization and reaction processes
Increased epithelial stem cell traits in advanced endometrial endometrioid carcinoma
<p>Abstract</p> <p>Background</p> <p>It has been recognized cancer cells acquire characters reminiscent of those of normal stem cells, and the degree of stem cell gene expression correlates with patient prognosis. Lgr5(+) or CD133(+) epithelial stem cells (EpiSCs) have recently been identified and these cells are susceptible to neoplastic transformation. It is unclear, however, whether genes enriched in EpiSCs also contribute in tumor malignancy. Endometrial endometrioid carcinoma (EEC) is a dominant type of the endometrial cancers and is still among the most common female cancers. Clinically endometrial carcinoma is classified into 4 FIGO stages by the degree of tumor invasion and metastasis, and the survival rate is low in patients with higher stages of tumors. Identifying genes shared between advanced tumors and stem cells will not only unmask the mechanisms of tumor malignancy but also provide novel therapeutic targets.</p> <p>Results</p> <p>To identify EpiSC genes in late (stages III-IV) EECs, a molecular signature distinguishing early (stages I-II) and late EECs was first identified to delineate late EECs at the genomics level. ERBB2 and CCR1 were genes activated in late EECs, while APBA2 (MINT2) and CDK inhibitor p16 tumor suppressors in early EECs. MAPK pathway was significantly up in late EECs, indicating drugs targeting this canonical pathway might be useful for treating advanced EECs. A six-gene mini-signature was further identified to differentiate early from advanced EECs in both the training and testing datasets. Advanced, invasive EECs possessed a clear EpiSC gene expression pattern, explaining partly why these tumors are more malignant.</p> <p>Conclusions</p> <p>Our work provides new insights into the pathogenesis of EECs and reveals a previously unknown link between adult stem cells and the histopathological traits of EECs. Shared EpiSC genes in late EECs may contribute to the stem cell-like phenotypes shown by advanced tumors and hold the potential of being candidate therapeutic targets and novel prognosis biomarkers.</p
Unprecedented random lasing in 2D organolead halide single-crystalline perovskite microrods
Three-dimensional organic–inorganic hybrid halide perovskites have been demonstrated as great materials for applications in optoelectronics and photonics. However, their inherent instabilities in the presence of moisture, light, and heat may hinder their commercialization. Alternatively, emerging two-dimensional (2D) organic–inorganic hybrid perovskites have recently attracted increasing attention owing to their great environmental stability and inherent natural quantum-well structure. In this work, we have synthesized a high-quality long-chain organic diammonium spacer assisted 2D hybrid perovskite FA-(N-MPDA)PbBr4 (FA = formamidinium and N-MPDA = N-methylpropane-1,3-diammonium) by the slow evaporation at constant temperature method. The millimeter-sized single-crystalline microrods demonstrate low threshold random lasing behavior at room temperature. The single-crystalline 2D hybrid perovskite random laser achieved a very narrow linewidth (∼0.1 nm) with a low threshold (∼0.5 μJ cm−2) and a high quality factor (∼5350). Furthermore, the 2D hybrid microrod laser shows stable lasing emission with no measurable degradation after at least 2 h under continuous illumination, which substantially proves the stability of 2D perovskites. Our results demonstrate the promise of 2D organic–inorganic microrod-shaped perovskites and provide an important step toward the realization of high-performance optoelectronic devices
A Genome-Wide Association Study Identifies Susceptibility Variants for Type 2 Diabetes in Han Chinese
To investigate the underlying mechanisms of T2D pathogenesis, we looked for diabetes susceptibility genes that increase the risk of type 2 diabetes (T2D) in a Han Chinese population. A two-stage genome-wide association (GWA) study was conducted, in which 995 patients and 894 controls were genotyped using the Illumina HumanHap550-Duo BeadChip for the first genome scan stage. This was further replicated in 1,803 patients and 1,473 controls in stage 2. We found two loci not previously associated with diabetes susceptibility in and around the genes protein tyrosine phosphatase receptor type D (PTPRD) (P = 8.54×10−10; odds ratio [OR] = 1.57; 95% confidence interval [CI] = 1.36–1.82), and serine racemase (SRR) (P = 3.06×10−9; OR = 1.28; 95% CI = 1.18–1.39). We also confirmed that variants in KCNQ1 were associated with T2D risk, with the strongest signal at rs2237895 (P = 9.65×10−10; OR = 1.29, 95% CI = 1.19–1.40). By identifying two novel genetic susceptibility loci in a Han Chinese population and confirming the involvement of KCNQ1, which was previously reported to be associated with T2D in Japanese and European descent populations, our results may lead to a better understanding of differences in the molecular pathogenesis of T2D among various populations
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
Genome-wide association study of lung adenocarcinoma in East Asia and comparison with a European population
Lung adenocarcinoma is the most common type of lung cancer. Known risk variants explain only a small fraction of lung adenocarcinoma heritability. Here, we conducted a two-stage genome-wide association study of lung adenocarcinoma of East Asian ancestry (21,658 cases and 150,676 controls; 54.5% never-smokers) and identified 12 novel susceptibility variants, bringing the total number to 28 at 25 independent loci. Transcriptome-wide association analyses together with colocalization studies using a Taiwanese lung expression quantitative trait loci dataset (n = 115) identified novel candidate genes, including FADS1 at 11q12 and ELF5 at 11p13. In a multi-ancestry meta-analysis of East Asian and European studies, four loci were identified at 2p11, 4q32, 16q23, and 18q12. At the same time, most of our findings in East Asian populations showed no evidence of association in European populations. In our studies drawn from East Asian populations, a polygenic risk score based on the 25 loci had a stronger association in never-smokers vs. individuals with a history of smoking (P interaction = 0.0058). These findings provide new insights into the etiology of lung adenocarcinoma in individuals from East Asian populations, which could be important in developing translational applications
Genome-wide association study of lung adenocarcinoma in East Asia and comparison with a European population.
Lung adenocarcinoma is the most common type of lung cancer. Known risk variants explain only a small fraction of lung adenocarcinoma heritability. Here, we conducted a two-stage genome-wide association study of lung adenocarcinoma of East Asian ancestry (21,658 cases and 150,676 controls; 54.5% never-smokers) and identified 12 novel susceptibility variants, bringing the total number to 28 at 25 independent loci. Transcriptome-wide association analyses together with colocalization studies using a Taiwanese lung expression quantitative trait loci dataset (n = 115) identified novel candidate genes, including FADS1 at 11q12 and ELF5 at 11p13. In a multi-ancestry meta-analysis of East Asian and European studies, four loci were identified at 2p11, 4q32, 16q23, and 18q12. At the same time, most of our findings in East Asian populations showed no evidence of association in European populations. In our studies drawn from East Asian populations, a polygenic risk score based on the 25 loci had a stronger association in never-smokers vs. individuals with a history of smoking (Pinteraction = 0.0058). These findings provide new insights into the etiology of lung adenocarcinoma in individuals from East Asian populations, which could be important in developing translational applications