The role of design-principles in designing courses that promote collaborative learning in higher-education

Design-patterns and design-principles represent two approaches, which elicit design knowledge from successful learning environments and formulate it as design guidelines. The two approaches are fairly similar in their strategies, but differ in their research origins. This study stems from the design-principles approach, and explores how learning is affected by curriculum-materials designed according to two main design-principles: (a) engage learners in peer instruction, and (b) reuse student artifacts as resource for further learning. These principles were employed in three higher-education courses and examined with 385 students. Data analysis was conducted in two trajectories: In the “bird’s eye view” trajectory we used a “feature” unit of analysis to illustrate how learning was supported by features designed according to the two design-principles in each of the courses. In the “design-based research” trajectory we focused on one feature, a web-based Jigsaw activity, in a philosophy of education course, and demonstrated how it was refined via three design iterations. Students were required to specialize in one of three philosophical perspectives, share knowledge with peers who specialized in other perspectives, and reuse the shared knowledge in new contexts. Outcomes indicated that the design in the first iteration did not sufficiently support student ability to apply the shared knowledge. Two additional design-principles were employed in the next iterations: (c) provide knowledge representation and organization tools, and (d) employ multiple social-activity structures. The importance of combining several design-principles for designing curricular materials is discussed in terms of Alexander’s design-pattern language and his notion of referencing between design-patterns.     

Bridging the requirements–implementation modeling gap with object–process methodology

A model-based system development cycle involves two semantically distinct aspects: the requirements specification and the implementation model. Due to the conceptual and semantic differences between these two major system lifecycle stages, the transition from requirements to implementation is inherently a noncoherent process. Consequently, the system requirements are not faithfully transformed into the working system. This paper introduces an effective solution via an Integrated Modeling Paradigm (IMP) that combines the requirements and implementation domain models into a unified system model that continuously represents the system as it evolves. The IMP was implemented in an Object–Process Methodology (OPM) development environment. This implementation reinforces OPM with the capability to bridge the significant conceptual gap that lies right at the heart of the development process. A user survey has shown that this OPM-based solution is easy to use and can indeed help bridge the information gap, yielding a better match between the required and implemented systems than the currently accepted practice.     

Incremental arc segmentation algorithm and its evaluation

We present an incremental arc segmentation algorithm, which recovers the vectorized arc fragments obtained by the vectorization of a piece of arc image in a stepwise fashion. Due to proper threshold selection and consistent checking of cocircularity of the assumed arc pieces, the algorithm accurately constructs arcs from the vector input. Nearly 200 synthetic arcs, ranging in radius from five to 50 pixels, in open angle from 1/8π to 2π, and in thickness from one to nine pixels, are used in the experiments and evaluation. Parts of six real drawings, containing about 200 arcs, are also processed. The algorithm works well for arc segments greater than 10 pixels in radius, π/4 in angle, and one pixel in width     

Effectiveness of an Internet-based program for reducing risk factors for eating disorders.

This study evaluated an Internet-delivered computer-assisted health education (CAHE) program designed to improve body satisfaction and reduce weight/shape concerns—concerns that have been shown to be risk factors for the development of eating disorders in young women. Participants were 60 women at a public university randomly assigned to either an intervention or control condition. Intervention participants completed the CAHE program Student Bodies. Measures of body image and disordered eating attitudes were assessed at baseline, postintervention, and 3-month follow-up. At follow-up, intervention participants, compared with controls, reported a significant improvement in body image and a decrease in drive for thinness. This program provides evidence for the feasibility and effectiveness of providing health education by means of the Internet. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reducing risk factors for eating disorders: Comparison of an Internet- and a classroom-delivered psychoeducational program.

This controlled trial compared Internet- (Student Bodies [SB]) and classroom-delivered (Body Traps [BT]) psychoeducational interventions for the reduction of body dissatisfaction and disordered eating behaviors/attitudes with a control condition. Participants were 76 women at a private university who were randomly assigned to SB, BT, or a wait-list control (WLC) condition. Measures of body image and eating attitudes and behaviors were measured at baseline, posttreatment, and 4-month follow-up. At posttreatment, participants in SB had significant reductions in weight/shape concerns and disordered eating attitudes compared with those in the WLC condition. At follow-up, disordered behaviors were also reduced. No significant effects were found between the BT and WLC conditions. An Internet-delivered intervention had a significant impact on reducing risk factors for eating disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Electrically controlled molecular recognition harnessed to activate a cellular response

Seamless embedment of electronic devices in biological systems is expected to add the outstanding computing power, memory, and speed of electronics to the biochemical toolbox of nature. Such amalgamation requires transduction of electronic signals into biochemical cues that affect cells. Inspired by biology, where pathways are directed by molecular recognition, we propose and demonstrate a generic electrical-to-biological transducer comprising a two-state electronic antigen and a chimeric cell receptor engineered to bind the antigen exclusively in its "on" state. T-cells expressing these receptors remain inactivated with the antigen in its "off" state. Switching the antigen to its "on" state by an electrical signal leads to its recognition by the T-cells and correspondingly to cell activation.     

Expert Panel Workshop Consensus Statement on the Role of the Environment in the Development of Autoimmune Disease

Autoimmune diseases include 80 or more complex disorders characterized by self-reactive, pathologic immune responses in which genetic susceptibility is largely insufficient to determine disease onset. In September 2010, the National Institute of Environmental Health Sciences (NIEHS) organized an expert panel workshop to evaluate the role of environmental factors in autoimmune diseases, and the state of the science regarding relevant mechanisms, animal models, and human studies. The objective of the workshop was to analyze the existing data to identify conclusions that could be drawn regarding environmental exposures and autoimmunity and to identify critical knowledge gaps and areas of uncertainty for future study. This consensus document summarizes key findings from published workshop monographs on areas in which “confident” and “likely” assessments were made, with recommendations for further research. Transcribed notes and slides were reviewed to synthesize an overview on exposure assessment and questions addressed by interdisciplinary panels. Critical advances in the field of autoimmune disease research have been made in the past decade. Collaborative translational and interdisciplinary research is needed to elucidate the role of environmental factors in autoimmune diseases. A focus on exposure assessment methodology is needed to improve the effectiveness of human studies, and more experimental studies are needed to focus on causal mechanisms underlying observed associations of environmental factors with autoimmune disease in humans.     

A Smart Sensor System for Carbon Monoxide Detection

This paper illustrates a smart sensor system for carbonmonoxide detection. An innovative technological approach hasbeen pursued to fabricate gas sensors on silicon substrate, compatiblewith IC fabrication. A mixed analog-digital electronic interfaceprocesses the outputs of three sensors to compensate relativehumidity and interfering gases. Sigma-delta signal processingand low-frequency noise reduction techniques are used to minimizesilicon area and to meet the required performance in a standardCMOS technology.     

一种在矢量基础上进行图形识别的通用方法

本文描述了一种在矢量基础上进行图形识别的通用方法．该方法包括２个步骤：第１步,寻找组成该图形的第１个关键图素;第２步,根据该图形的构造模式,从第１个关键图素出发,不断在其周围区域寻找组成该图形的其它图素．本文还提出了一种新的平面空间数据结构——位置索引．这种数据结构把平面图上的图形及图素用它们的平面位置索引组织起来,从而提高了按区域位置查找的效率．本文还介绍了该方法的２个应用实例：虚线识别和剖面线识别.