Synthesis-Oriented Situational Analysis in User Interface Design

Analytic evaluation is a term describing a class of techniques for examining a representation of a user interface design, discovering design flaws and/or predicting user task performance. In our work with analytic evaluation, we have observed limitations on the effectiveness and efficiency of analytic techniques for formative evaluation supporting the iterative design and re-design cycle. Here we support those observations with arguments based on theoretical limitations of the models underlying these techniques. By way of comparison we discuss desirable characteristics for an alternative approach. In our search for such an alternative, we have developed the Task Mapping Model, a substantively different approach to analysis for supporting the user interface design. We briefly describe the Task Mapping Model and give some examples illustrating its desirable characteristics

Static and Dynamic Software Quality Metric Tools

The ability to detect and predict poor software quality is of major importance to software engineers, managers, and quality assurance organizations. Poor software quality leads to increased development costs and expensive maintenance. With so much attention on exacerbated budgetary constraints, a viable alternative is necessary. Software quality metrics are designed for this purpose. Metrics measure aspects of code or PDL representations, and can be collected and used throughout the life cycle [RAMC85]

Measurement of Ada Throughout the Software Development Life Cycle

Quality enhancement has now become a major factor in software production. Software metrics have demonstrated their ability to predict source code complexity at design time and to predict maintainability of a software system from source code. Obviously metrics can assist software developers in the enhancement of quality. Tools which automatically generate metrics for Ada are increasing in popularity. This paper describes an existing tool which produces software metrics for Ada that may be used throughout the software development life cycle. This tool, while calculating established metrics, also calculates a new structure metric that is designed to capture communication interface complexity. Measuring designs written using Ada as a PDL allows designers early feedback on possible problem areas in addition to giving direction on testing strategies

A Grassroots Approach to Graduate Teaching Assistant Mentoring

Graduate students, whether master's or doctoral candidates, benefit greatly from their academic experiences. However, graduate school is not limited to course work and research, but it also includes teaching experiences as graduate teaching assistants (GTAs). Although GTAs are technically proficient in course materials, other factors can cause teaching experiences to go awry for them, their students, or the course supervisor. These factors arise out of a need for quality training on issues including pedagogy, interaction resolution, organizational concerns, and professional matters. This paper provides a grassroots approach to improve teachine techniques through GTA mentoring. GTAs are encouraged, with materials supplied here, to seek out and consult with more experienced GTAs who will serve as their mentors

Communicational Measurement

A software system is an aggregate of communicating modules. The interfaces supporting module (procedure, etc.) communication characterize the system. Therefore, understanding these interfaces (areas of communication) gives a better description of system complexity. Understanding in an empirical sense implies measuring, and measuring interfaces involves examining both the communicational environment and the exchanged data. There are several different measures associated with the communication environment. Obviously, the structure or nesting level at the communication ping is very interesting. The need to measure the data communicated also raises some very interesting questions concerned with data type and expressional form. This paper reports on the efforts at Virginia Tech to measure, and thus capture, the complexities of software interfaces. Analyzing an Ada system of 85,000 lines of code validated the measures proposed here. The results of this research are very encouraging

A Reliability Model Incorporating Software Quality Factors

In this paper we describe our initial work on a long-term project to develop and validate a reliability model and a new class of software complexity metrics which are related to this model. In contrast to previous "black box" approaches, the reliability model is novel because it incorporates knowledge about the system in the form of quantitative software complexity metrics. While the initial model uses existing software metrics a parallel effort in this project is investigating new classes of metrics, interface and dynamic metrics, which are useful in their own right but are also of particular relevance to the reliability model. The initial definitions of both the model and the metrics are given along with a description of the next research milestones

Exome-Sequencing Confirms DNAJC5 Mutations as Cause of Adult Neuronal Ceroid-Lipofuscinosis

We performed whole-exome sequencing in two autopsy-confirmed cases and an elderly unaffected control from a multigenerational family with autosomal dominant neuronal ceroid lipofuscinosis (ANCL). A novel single-nucleotide variation (c.344T>G) in the DNAJC5 gene was identified. Mutational screening in an independent family with autosomal dominant ANCL found an in-frame single codon deletion (c.346_348 delCTC) resulting in a deletion of p.Leu116del. These variants fulfill all genetic criteria for disease-causing mutations: they are found in unrelated families with the same disease, exhibit complete segregation between the mutation and the disease, and are absent in healthy controls. In addition, the associated amino acid substitutions are located in evolutionarily highly conserved residues and are predicted to functionally affect the encoded protein (CSPα). The mutations are located in a cysteine-string domain, which is required for membrane targeting/binding, palmitoylation, and oligomerization of CSPα. We performed a comprehensive in silico analysis of the functional and structural impact of both mutations on CSPα. We found that these mutations dramatically decrease the affinity of CSPα for the membrane. We did not identify any significant effect on palmitoylation status of CSPα. However, a reduction of CSPα membrane affinity may change its palmitoylation and affect proper intracellular sorting. We confirm that CSPα has a strong intrinsic aggregation propensity; however, it is not modified by the mutations. A complementary disease-network analysis suggests a potential interaction with other NCLs genes/pathways. This is the first replication study of the identification of DNAJC5 as the disease-causing gene for autosomal dominant ANCL. The identification of the novel gene in ANCL will allow us to gain a better understanding of the pathological mechanism of ANCLs and constitutes a great advance toward the development of new molecular diagnostic tests and may lead to the development of potential therapies

Molecular basis for cellular retinoic acid-binding protein 1 in modulating CaMKII activation

Introduction: Cellular retinoic acid (RA)-binding protein 1 (CRABP1) is a highly conserved protein comprised of an anti-parallel, beta-barrel, and a helix-turn-helix segment outside this barrel. Functionally, CRABP1 is thought to bind and sequester cytosolic RA. Recently, CRABP1 has been established as a major mediator of rapid, non-genomic activity of RA in the cytosol, referred to as “non-canonical” activity. Previously, we have reported that CRABP1 interacts with and dampens the activation of calcium-calmodulin (Ca2+-CaM)-dependent kinase 2 (CaMKII), a major effector of Ca2+ signaling. Through biophysical, molecular, and cellular assays, we, herein, elucidate the molecular and structural mechanisms underlying the action of CRABP1 in dampening CaMKII activation.Results: We identify an interaction surface on CRABP1 for CaMKII binding, located on the beta-sheet surface of the barrel, and an allosteric region within the helix segment outside the barrel, where both are important for interacting with CaMKII. Molecular studies reveal that CRABP1 preferentially associates with the inactive form of CaMKII, thereby dampening CaMKII activation. Alanine mutagenesis of residues implicated in the CaMKII interaction results in either a loss of this preference or a shift of CRABP1 from associating with the inactive CaMKII to associating with the active CaMKII, which corresponds to changes in CRABP1’s effect in modulating CaMKII activation.Conclusions: This is the first study to elucidate the molecular and structural basis for CRABP1’s function in modulating CaMKII activation. These results further shed insights into CRABP1’s functional involvement in multiple signaling pathways, as well as its extremely high sequence conservation across species and over evolution

Planet Hunters: Assessing the Kepler Inventory of Short Period Planets

We present the results from a search of data from the first 33.5 days of the Kepler science mission (Quarter 1) for exoplanet transits by the Planet Hunters citizen science project. Planet Hunters enlists members of the general public to visually identify transits in the publicly released Kepler light curves via the World Wide Web. Over 24,000 volunteers reviewed the Kepler Quarter 1 data set. We examine the abundance of \geq 2 R\oplus planets on short period (< 15 days) orbits based on Planet Hunters detections. We present these results along with an analysis of the detection efficiency of human classifiers to identify planetary transits including a comparison to the Kepler inventory of planet candidates. Although performance drops rapidly for smaller radii, \geq 4 R\oplus Planet Hunters \geq 85% efficient at identifying transit signals for planets with periods less than 15 days for the Kepler sample of target stars. Our high efficiency rate for simulated transits along with recovery of the majority of Kepler \geq 4 R\oplus planets suggest suggests the Kepler inventory of \geq 4 R\oplus short period planets is nearly complete.Comment: 41 pages,13 figures, 8 tables, accepted to Ap

Binary-induced collapse of a compact, collisionless cluster

We improve and extend Shapiro's model of a relativistic, compact object which is stable in isolation but is driven dynamically unstable by the tidal field of a binary companion. Our compact object consists of a dense swarm of test particles moving in randomly-oriented, initially circular, relativistic orbits about a nonrotating black hole. The binary companion is a distant, slowly inspiraling point mass. The tidal field of the companion is treated as a small perturbation on the background Schwarzschild geometry near the hole; the resulting metric is determined by solving the perturbation equations of Regge and Wheeler and Zerilli in the quasi-static limit. The perturbed spacetime supports Bekenstein's conjecture that the horizon area of a near-equilibrium black hole is an adiabatic invariant. We follow the evolution of the system and confirm that gravitational collapse can be induced in a compact collisionless cluster by the tidal field of a binary companion.Comment: 9 Latex pages, 14 postscript figure