Designing smarter touch-based interfaces for educational contexts

In next-generation classrooms and educational environments, interactive technologies such as surface computing, natural gesture interfaces, and mobile devices will enable new means of motivating and engaging students in active learning. Our foundational studies provide a corpus of over 10,000 touch interactions and nearly 7,000 gestures collected from nearly 70 adults and children aged 7 years and above, which can help us understand the characteristics of children’s interactions in these modalities and how they differ from adults. Based on these data, we identify key design and implementation challenges of supporting children’s touch and gesture interactions, and we suggest ways to address them. For example, we find children have more trouble successfully acquiring onscreen targets and having their gestures recognized than do adults, especially the youngest age group (7–10 years old). The contributions of this work provide a foundation that will enable touch-based interactive educational apps that increase student success.     

Enzymatic Addition of Alcohols to Terpenes by Squalene Hopene Cyclase Variants

Squalene–hopene cyclases (SHCs) catalyze the polycyclization of squalene into a mixture of hopene and hopanol. Recently, amino-acid residues lining the catalytic cavity of the SHC from Alicyclobacillus acidocaldarius were replaced by small and large hydrophobic amino acids. The alteration of leucine 607 to phenylalanine resulted in increased enzymatic activity towards the formation of an intermolecular farnesyl–farnesyl ether product from farnesol. Furthermore, the addition of small-chain alcohols acting as nucleophiles led to the formation of non-natural ether-linked terpenoids and, thus, to significant alteration of the product pattern relative to that obtained with the wild type. It is proposed that the mutation of leucine at position 607 may facilitate premature quenching of the intermediate by small alcohol nucleophiles. This mutagenesis-based study opens the field for further intermolecular bond-forming reactions and the generation of non-natural products.     

Fluorescent Probe DCVJ Shows High Sensitivity for Characterization of Amyloid β-Peptide Early in the Lag Phase

The aggregation of intrinsically disordered and misfolded proteins in the form of oligomers and fibrils plays a crucial role in a number of neurological and neurodegenerative diseases. Currently, most probes and biophysical techniques that detect and characterize fibrils at high resolution fail to show sensitivity and binding for oligomers. Here, we show that 9-(dicyano-vinyl)julolidine (DCVJ), a class of molecular rotor, binds amyloid beta (Aβ) early aggregates, and we report the kinetics as well as packing of the oligomer formation. The binding of DCVJ to Aβ40 increased its emission intensity with time at 510 nm and produced a second excimer peak at 575 nm. However, DCVJ did not bind to the prefibrillar aggregates of Aβ42, which indicated that the oligomers formed by Aβ40 and Aβ42 were not the same. The F4C F19W mutant of Aβ40, which did not form fibrils, also bound DCVJ, but the emission spectral profile varied from that of the wild-type (WT). Atomic force microscopy images of WT Aβ40, the F4C F19W mutant, and Aβ42 oligomers displayed differences in size and shape, confirming the difference in their DCVJ spectra. The effect of epigallocatechin-3-gallate (EGCG) on the reduction of Aβ42 fibrils was also observed with finer detail than with other techniques. The results of this study show that DCVJ detects early aggregates and provides valuable information regarding the oligomer kinetics, packing, and mechanism of formation.     

Nanocluster formation and stabilization fundamental studies: ranking the nanocluster stabilizing ability of halides

Following a brief introduction to the nanocluster stabilization literature and DLVO (Derjaugin-Landau-Verwey-Overbeek) theory of colloidal stability, F-, CI-, Br-, and I- are evaluated for their efficacy in the formation and stabilization of prototype Ir(O)n nanoclusters prepared from a [(1,5-COD)lr(CH3CN)2][BF4] precursor in both acetone and propylene carbonate solvent. First, under conditions utilized previously for establishing an anion stabilization series ("Standard Conditions," 1.2 mM Ir precursor concentration at 22 degrees C in acetone solvent), the 5 criteria developed in 2002 for ranking nanocluster stabilizers are evaluated for each halide (each with 1 equiv BF4 present from the Ir precursor). Under Standard Conditions, bulk metal is the final product (i.e., no stable nanoclusters) in the presence of each of the four halides, as well as for BF4 in the absence of any halide. Next, each halide, again in the presence of 1 equiv BF4, is evaluated under "Improved Conditions" (0.24 mM Ir precursor concentration at 60 degrees C in propylene carbonate solvent), propylene carbonate being known to be a preferred nanocluster solvent in the presence of anionic (electrostatic) stabilizers. Nanocluster syntheses under the Improved Conditions did, as expected, yield Ir(O)n nanoclusters for each of the four halide plus BF4 systems as well as BF4 alone, although none of these nanoclusters are isolable from solution. Importantly, even the traditionally weakly coordinating BF4 is shown to contribute significantly to nanocluster stability in the high dielectric constant solvent propylene carbonate. Hence, the importance of anions in conjunction with a high dielectric constant solvent for nanocluster formation and stabilization is illustrated.     

Development of a Cloud Trust Label: A Delphi Approach

The purpose of this research is to identify the potential information components of an online, real-time trust label, which is proposed as a communication mechanism to encourage trust in cloud service providers and cloud computing products. An online Delphi process was used with 28 cloud computing experts (including vendors, software providers, and legal and business representatives). The proposed label contains 81 information components, covering the cloud service provider (e.g. physical location, legal jurisdiction), the cloud service itself (e.g. data location, security, backup, certification), and a historical service-level summary (e.g. uptime data, support response times). The potential benefits of such a label to encourage trustworthiness perceptions and trust behaviors in the cloud computing environment are explored. Limitations of the study are highlighted, and further research studies are suggested to test the concept of the label and to refine the components of the label itself.     

Autonomic correlates of attention-deficit/hyperactivity disorder and oppositional defiant disorder in preschool children.

Numerous studies have revealed autonomic underarousal in conduct-disordered adolescents and antisocial adults. It is unknown, however, whether similar autonomic markers are present in at-risk preschoolers. In this study, the authors compared autonomic profiles of 4- to 6-year-old children with attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD; n = 18) with those of age-matched controls (n = 20). Children with ADHD and ODD exhibited fewer electrodermal responses and lengthened cardiac preejection periods at baseline and during reward. Although group differences were not found in baseline respiratory sinus arrhythmia, heart rate changes among ADHD and ODD participants were mediated exclusively by parasympathetic withdrawal, with no independent sympathetic contribution. Heart rate changes among controls were mediated by both autonomic branches. These results suggest that at-risk preschoolers are autonomically similar to older externalizing children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The discrepancy-attribution hypothesis: II. Expectation, uncertainty, surprise, and feelings of familiarity.

In the accompanying article (B. W. A. Whittlesea and L. D. Williams, see record 2000-14052-001), surprising violation of and expectation was observed to cause an illusion of familiarity. The authors interpreted that evidence as support for the discrepancy-attribution hypothesis. This article extended the scope of that hypothesis, investigating the consequences of surprising validation of expectations. Ss were shown recognition probes as completions of sentence stems. Their expectations were manipulated by presenting predictive, nonpredictive, and inconsistent stems. Predictive stems caused an illusion of familiarity, but only when the Ss also experienced uncertainty about the outcome. That is, as predicted by the discrepancy-attribution hypothesis, feelings of familiarity occurred only when processing of a recognition target caused surprise. The article provides a discussion of the ways in which a perception of discrepancy can come about, as well as the origin and nature of unconscious expectation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Integrierte Wertschöpfungsnetzwerke – Chancen und Potenziale durch Industrie 4.0

The Smart Factory is the central element of Industry 4.0 and establishes the foundation to enable integrated value chains across companies. The linkage of information along value chains offers a wide range of opportunities and potentials to realize new innovative solutions.