教育神经科学的未来:建构学习发展路径的工具

在教育神经科学领域,我们需要可靠的脑科学知识为学与教奠定坚实的基础。在教学实践中,应该尊重学生的兴趣以及他们独特的学习通路。在教育神经科学中,我们已经创建了一种通用的量表来评估孩子们的认知发展以及他们在校学习,这种评价重视对学生学习的支持与促进。在教育神经科学的研究中,重要的是,科学家与教育工作者相互合作,建立研究型学校,将心智、脑与教育领域的知识联系起来,以支持并促进学生的学习。     

Using rasch measurement to score,evaluate, and improve examinations in an anatomy course

Any examination that involves moderate to high stakes implications for examinees should be psychometrically sound and legally defensible. Currently, there are two broad and competing families of test theories that are used to score examination data. The majority of instructors outside the high‐stakes testing arena rely on classical test theory (CTT) methods. However, advances in item response theory software have made the application of these techniques much more accessible to classroom instructors. The purpose of this research is to analyze a common medical school anatomy examination using both the traditional CTT scoring method and a Rasch measurement scoring method to determine which technique provides more robust findings, and which set of psychometric indicators will be more meaningful and useful for anatomists looking to improve the psychometric quality and functioning of their examinations. Results produced by the more robust and meaningful methodology will undergo a rigorous psychometric validation process to evaluate construct validity. Implications of these techniques and additional possibilities for advanced applications are also discussed. Anat Sci Educ 7: 450–460. © 2014 American Association of Anatomists.     

Moderation and consistency of teacher judgement: Teachers’ views

Major curriculum and assessment reforms in Australia have generated research interest in issues related to standards, teacher judgement and moderation. This article is based on one related inquiry of a large‐scale Australian Research Council Linkage project conducted in Queensland. This qualitative study analysed interview data to identify teachers’ views on standards and moderation as a means to achieving consistency of teacher judgement. A complementary aspect of the research involved a blind review that was conducted to determine the degree of teacher consistency without the experience of moderation. Empirical evidence was gained that most teachers, of the total interviewed, articulated a positive attitude towards the use of standards in moderation and perceived that this process produces consistency in teachers’ judgements. Context was identified as an important influential factor in teachers’ judgements and it was concluded that teachers’ assessment beliefs, attitudes and practices impact on their perceptions of the value of moderation practice and the extent to which consistency can be achieved.     

Assessing environmental understanding: an application of the concept mapping strategy

Despite its importance as a central goal in environmental education, there appears to be little consensus about how best to document, assess and evaluate understanding of environmental concepts. This illustrative case study describes and demonstrates the use of the concept mapping strategy as an effective tool for assessing environmental understanding. Data were collected from 325 middle school‐aged (11–14 years) individuals and comparisons were made among those enrolled in a model, university‐based, informal, residential marine education program (viz. MarineQuest) and a matched group of non‐participating students. Using a non‐randomized Solomon Four Group experimental design, differences in the structural complexity and content validity of knowledge about marine animal life were explored. Results reveal significant differences in the frequencies of concepts, relationships, levels of hierarchy, branching and cross‐linking and in the frequencies and types of critical concepts depicted. In all cases, where differences were found, they favored participants who enrolled in the environmental education intervention. The findings suggest that concept maps offer a valuable alternative or adjunct to traditional pencil and paper tests and provide both a qualitative and a quantitative measure of conceptual understanding.     

Predicting abuse-prone parental attitudes and discipline practices in a nationally representative sample

OBJECTIVE: According to sociological and ecological models of abuse, typically nonabusive parents could behave abusively towards their children under certain circumstances. The purpose of this study was to examine factors that place parents at risk of abusing their children by predicting parents' use of discipline practices and attitudes that may bias parents towards abusive behaviors, which we refer to as abuse-proneness. METHOD: A telephone interview was administered by the Gallup Organization to a nationally representative sample of 1,000 parents. Using a set of theoretically relevant risk factors, multiple regression was used to predict variations in parental attitudes (i.e., attitudes towards physical discipline and attitudes that devalue children) and parental discipline practices (i.e., physical discipline, nonphysical discipline, and verbal abuse). RESULTS: The findings confirmed the importance of examining elements of parental attitudes, history, personality characteristics, as well as religion and ideology in predicting abuse proneness. Child age also was an important predictor in all analyses except predicting parental attitudes that devalue children. The findings suggest also, however, that it may be unduly simplified to regard parents as somewhere on a continuum of nonpunitive to punitive disciplinarians. Social isolation was not a significant predictor in any of the analyses. CONCLUSIONS: Although many important theoretical predictors of abuse proneness were confirmed, many questions arise regarding the diversity of discipline practices that parents use, and the relevance of child's age and social isolation in predicting abuse proneness. Implications for practitioners and future research are discussed.     

Magnetographic array for the capture and enumeration of single cells and cell pairs

We present a simple microchip device consisting of an overlaid pattern of micromagnets and microwells capable of capturing magnetically labeled cells into well-defined compartments (with accuracies >95%). Its flexible design permits the programmable deposition of single cells for their direct enumeration and pairs of cells for the detailed analysis of cell-cell interactions. This cell arraying device requires no external power and can be operated solely with permanent magnets. Large scale image analysis of cells captured in this array can yield valuable information (e.g., regarding various immune parameters such as the CD4:CD8 ratio) in a miniaturized and portable platform.The emergent need for point-of-care devices has spurred development of simplified platforms to organize cells across well-defined templates.¹ These devices employ passive microwells, immunospecific adhesive islands, and electric, optical, and acoustic traps to manipulate cells.^2–6 In contrast, magnetic templating can control the spatial organization of cells through its ability to readily program ferromagnetic memory states.⁷ While it has been applied to control the deposition of magnetic beads,^8–13 it has not been used to direct the deposition of heterogeneous cell pairs, which may help provide critical insight into the function of single cells.^14,15 As such, we developed a simple magnetographic device capable of arraying single cells and pairs of cells with high fidelity. We show this magnetic templating tool can use immunospecific magnetic labels for both the isolation of cells from blood and their organization into spatially defined wells.We used standard photolithographic techniques to fabricate the microchips (see supplementary material¹⁶). Briefly, an array of 10 × 30 μm cobalt micromagnets were patterned by a photolithographic liftoff process and overlaid with a pattern of dumbbell-shaped microwells formed in SU-8 photoresist (Fig. 1(a)). The micromagnets were designed to produce a predominantly vertical field in the microwells by aligning the ends of the micromagnet at the center of each well of the dumbbell. These features were deposited across an area of ≈400 mm² (>50 000 well pairs per microchip) (Fig. 1(b)). Depending on the programmed magnetization state with respect to the external field, magnetic beads or cells were attracted to one pole and repelled by the other pole of each micromagnet, leading to a biased deposition (Fig. 1(c)).¹²Open in a separate windowFIG. 1.Magnetographic array for single cell analysis. (a) SEM image of the dumbbell-shaped well pairs for capturing magnetically labelled cells. (b) Photograph of the finished device. (c) An array of well pairs displaying a pitch of 60 × 120 μm before (top) and 10 min after the deposition of magnetic beads (bottom).To demonstrate the capability of the array to capture cells into a format amenable for rapid image processing, we organized CD3+ lymphocytes using only hand-held permanent magnets. We isolated CD3+ lymphocytes from blood via positive selection using anti-CD3 magnetic nanoparticles (EasySep™, STEMCELL Technologies) with purities confirmed by flow cytometry (97.8%; see supplementary material¹⁶). We then stained 1 × 10⁶ CD3+ cells with anti-CD8 Alexa-488 and anti-CD4 Alexa-647 (5 μl of each antibody in 100 μl for 20 min; BD Bioscience) to determine the CD4:CD8 ratio, a prognostic ratio for assessing the immune system.^17,18Variably spaced neodymium magnets (0.5 in. × 0.5 in. × 1 in.; K&J Magnetics, Inc.) were fixed on either side of the microchip to generate a tunable magnetic field (0–400 G; Fig. 2(a)). Using this setup, fluorescently labeled cells were deposited, and the populations of CD4+ and CD8+ cells were indiscriminately arrayed, imaged, and enumerated using ImageJ. The resulting CD4:CD8 ratio of 1.84 ± 0.18 (Fig. 2(b)) was confirmed by flow cytometry with a high correlation (5.4% difference; Fig. 2(c)), indicating the magnetographic microarray can pattern cells for the rapid and accurate assessment of critical phenotypical parameters without complex equipment (e.g., function generators or flow cytometers).Open in a separate windowFIG. 2.CD8 analysis of CD3+ lymphocytes. (a) Photograph of the magnetographic device activated by permanent magnets (covered with green tape). The CD4:CD8 ratio determined by the (b) magnetographic microarray and (c) and (d) flow cytometry was 1.84 and 1.74, respectively.More complex operations, such as the programmed deposition of cell pairs, can be achieved by leveraging the switchable, bistable magnetization of the micromagnets for the detailed studies of cell-cell interactions (Figs. 3(a)–3(d)).¹² For these studies, a 200 G horizontal field generated from an electromagnetic coil was used to magnetize the micromagnets.¹⁹ We then captured different concentrations of magnetic beads as surrogates for cells (8.4 μm polystyrene, Spherotech, Inc.) and found that higher bead concentrations did not affect the capture accuracy (>95%; see supplementary material¹⁶).Open in a separate windowFIG. 3.Programmed pairing of magnetic beads and CD3+ lymphocytes. (a) Schematic of the magnetographic cell pair isolations. (b) Polarized micromagnets isolate cells of one type to one side in a vertical magnetic field and then cells of a second type to the other side when the field is reversed. (c) Fluorescent image of magnetically trapped green stained (top) and red stained (bottom) cell pairs. (d) SEM image of magnetically labeled cells in the microwells. (e) Capture accuracy of magnetic bead pairs. (Each color (and shape) represents the field strength of the reversed field.) (f) Change in the capture accuracy (loss) of initially captured beads after reversing the magnetic field. The capture accuracy of (g) magnetically labeled cell pairs and (h) the second magnetically labeled cell (for (e)–(h): n = 5; time starts from the deposition of the second set of cells or beads).The opposite side of each micromagnet was then populated with the second (yellow fluorescent) bead by reversing the direction of the applied magnetic field. We tested several field strengths (i.e., 10, 25, 40, or 55 G) to optimize the conditions for isolating the desired bead in the opposite well without ejecting the first bead. If the field strength was too large, the previously deposited beads could be ejected from their wells due to the repulsive magnetic force overcoming gravity.¹² As shown in Figure 3(e), increasing the field strength from 10 to 25 G significantly increased the capture accuracy at 60 min from the deposition of the second bead (p < 0.01), but increases from 25 to 55 G did not affect the capture accuracy (p > 0.10). As shown in Figure 3(f), higher field strengths (i.e., 40 and 55 G) resulted in lower capture accuracies compared to lower field strengths (i.e., 10 and 25 G) (p < 0.01), which was primarily due to ejection of the initially captured beads when the micromagnets reversed their polarity.We then arranged pairs of membrane dyed (calcein AM, Invitrogen; PKH26, Sigma) magnetically labeled CD3+ lymphocytes. First, red stained cells (150 μl of 2 × 10⁴ cells/ml) were deposited on the microchip in the presence of 250 G vertical magnetic field. After 20 min, the field was reversed (i.e., to 40, 55, and 70 G) and green stained cells (150 μl of 2 × 10⁴ cells/ml) were deposited on the microchip with images taken in 10 min intervals. Fluorescence images were overlaid (Fig. 3(c)) and the capture accuracy of cell pairs was determined (ImageJ).As seen in Figure 3(g), the capture accuracy of pairs of CD3+ lymphocytes was lower than that of magnetic beads (Fig. 3(e)). However, as shown in Figure 3(h), the second set of cells (green fluorescent) exhibited an average capture accuracy of 91.8% ± 1.9%. This indicates that the lower capture accuracy of cell pairs was either due to the ejection of initially captured (red fluorescent) cells or the migration of initially captured cells through the connecting channel, resulting from their relatively high deformability compared to magnetic beads.In summary, we developed a simple device capable of organizing magnetic particles, cells, and pairs of cells into well-defined compartments. A major advantage of this system is the use of specific magnetic labels to both isolate cells and program their deposition. While the design of this device does not enable dynamic control of the spacing between captured cell pairs as does some dielectrophoresis-based devices,²⁰ it can easily capture cells with high fidelity using only permanent magnets and has clinical relevance in the assessment of immune parameters. These demonstrations potentiate a relatively simple and robust device where highly organized spatial arrangement of cells facilitates rapid and accurate analyses towards a functional and low-cost point-of-care device.     

Public broadband investment priorities in the United States: an analysis of the broadband technology opportunities program

In 2009, U.S. Congress approved $7.2 billion to accelerate the deployment of advanced broadband networks and services to unserved and underserved regions of the country. Although primarily a short-term response to the economic crisis, the appropriation also indicates a willingness to seek a new balance between private sector and public sector initiatives in the development of the nation's broadband infrastructure. This paper is a first step in assessing the potential impact of the new government initiatives. It discusses in detail one component of the overall program, the Broadband Technology Opportunities Program (BTOP). The rationales and objectives of BTOP and its initial implementation are explored. Based on information in the BTOP database, 265 awards were examined to document award types, target communities, applications, technology, and access speeds. Whereas it is too early to assess the initiatives' effects on employment and other important social and economic objectives, it is appropriate to consider whether the awards made under the BTOP program advance a national broadband development agenda. Overall, they appear to. However, the present analysis found that projects focusing on minority populations may have received less emphasis in the BTOP awards than that announced in the stated goals of the program.     

Mind,Brain, and Education in the Digital Era

Computers are everywhere, and they are transforming the human world. The technology of computers and the Internet is radically changing the ways that people learn and communicate. In the midst of this technology‐driven revolution people need to examine the changes to analyze how they are altering interaction and human culture. The changes have already permeated societies around the world, altering learning, teaching, communication, politics, and most aspects of human interaction. The possibilities for improving educational effectiveness seem powerful, as a result of an information revolution with online access to infinite information and numerous teaching and learning activities of adults and children at school, at home, and in public places. An urgent need is for systematic longitudinal studies of what happens with learning and teaching as people use computers and play with the Internet. Perhaps the new technologies make possible a new kind of constructive dialogue, with intertwining of teaching and learning in a dynamic double helix of questions and answers, of modeling and experimentation. This special section will deal with (1) uses of new technologies to help people teach and learn more effectively, (2) uses of individual laptops to help children learn, (3) creation of new tools for learning and assessment, and (4) techniques that image brain structure and activity.