Towards a Theory of Analytical Behaviour: A Model of Decision-Making in Visual Analytics

This paper introduces a descriptive model of the human-computer processes that lead to decision-making in visual analytics. A survey of nine models from the visual analytics and HCI literature are presented to account for different perspectives such as sense-making, reasoning, and low-level human-computer interactions. The survey examines the people and computers (entities) presented in the models, the divisions of labour between entities (both physical and role-based), the behaviour of both people and machines as constrained by their roles and agency, and finally the elements and processes which define the flow of data both within and between entities. The survey informs the identification of four observations that characterise analytical behaviour - defined as decision-making facilitated by visual analytics: bilateral discourse, divisions of labour, mixed-synchronicity information flows, and bounded behaviour. Based on these principles, a descriptive model is presented as a contribution towards a theory of analytical behaviour. The future intention is to apply prospect theory, a economic model of decision-making under uncertainty, to the study of analytical behaviour. It is our assertion that to apply prospect theory first requires a descriptive model of the processes that facilitate decision-making in visual analytics. We conclude it necessary to measure the perception of risk in future work in order to apply prospect theory to the study of analytical behaviour using our proposed model

Representation Effects and Loss Aversion in Analytical Behaviour: An Experimental Study into Decision Making Facilitated by Visual Analytics

This paper presents the results of an experiment into the relationship between the representation of data and decision-making. Three hundred participants online, were asked to choose between a series of financial investment opportunities using data presented in line charts. A single dependent variable of investment choice was examined over four levels of varying display conditions and randomised data. Three variations to line chart visualisations provided a controlled factor between subjects divided into three groups; -˜standard’ line charts, -˜tall’ line charts, and one dual-series line chart. The final results revealed a consistent main effect and two other interactions between certain display conditions and decision-making. The findings of this paper are significant to the study visualisation and to the field of visual analytics. This experiment was devised as part of a study into Analytical Behaviour, defined as decision-making facilitated by visual analytics - a new topic that encompasses existing research and real-world applications

Design Spaces in Visual Analytics Based on Goals: Analytical Behaviour, Exploratory Investigation, Information Design & Perceptual Tasks

This paper considers a number of perspectives on design spaces in visual analytics and proposes a new set of four design spaces, based on user goals. Three of the user goals are derived from the literature and are categorised under the terms exploratory investigation, perceptual tasks, and information design. The fourth goal is categorised as analytical behaviour; a recently defined term referring to the study of decision-making facilitated by visual analytics. This paper contributes to the literature on decision-making in visual analytics with a survey of real-world applications within the analytical behaviour design space and by providing a new perspective on design spaces. Central to our analysis is the introduction of decision concepts and theories from economics into a visual analytics context. Given the recent interest in decision-making we wanted to understand the emerging topic of analytical behaviour as a design space and found it necessary to look at more than just decision-making to make a valuable contribution. The result is an initial framework suitable for use in the analysis or design of analytical behaviour applications

Investigation and characterization of constraint effects on flaw growth during fatigue loading of composite materials

An investigative program is presented in an attempt to add to the current understanding of constraint effects on the response of composite materials under cyclic loading. The objectives were: (1) to use existing data and to develop additional data in order to establish an understanding and quantitative description of flaw growth in unidirectional lamina under cyclic loading at different load direction to fiber direction angles; (2) to establish a similar understanding and description of flaw growth in lamina which are embedded in laminates between other unflawed lamina; (3) to determine the nature of the influence of constraint on flaw growth by quantitatively comparing the results of the tests; and (4) to develop a model and philosophy of constraints effects based on our investigative results

Space station integrated wall design and penetration damage control

The analysis code BUMPER executes a numerical solution to the problem of calculating the probability of no penetration (PNP) of a spacecraft subject to man-made orbital debris or meteoroid impact. The codes were developed on a DEC VAX 11/780 computer that uses the Virtual Memory System (VMS) operating system, which is written in FORTRAN 77 with no VAX extensions. To help illustrate the steps involved, a single sample analysis is performed. The example used is the space station reference configuration. The finite element model (FEM) of this configuration is relatively complex but demonstrates many BUMPER features. The computer tools and guidelines are described for constructing a FEM for the space station under consideration. The methods used to analyze the sensitivity of PNP to variations in design, are described. Ways are suggested for developing contour plots of the sensitivity study data. Additional BUMPER analysis examples are provided, including FEMs, command inputs, and data outputs. The mathematical theory used as the basis for the code is described, and illustrates the data flow within the analysis

Space station integrated wall design and penetration damage control

A methodology was developed to allow a designer to optimize the pressure wall, insulation, and meteoroid/debris shield system of a manned spacecraft for a given spacecraft configuration and threat environment. The threat environment consists of meteoroids and orbital debris, as specified for an arbitrary orbit and expected lifetime. An overall probability of no penetration is calculated, as well as contours of equal threat that take into account spacecraft geometry and orientation. Techniques, tools, and procedures for repairing an impacted and penetrated pressure wall were developed and tested. These techniques are applied from the spacecraft interior and account for the possibility of performing the repair in a vacuum. Hypervelocity impact testing was conducted to: (1) develop and refine appropriate penetration functions, and (2) determine the internal effects of a penetration on personnel and equipment

ELBOW FLEXOR MUSCLE FUNCTION AND UPPER ARM GIRTH FOLLOWING CONCURRENT STRENGTH AND ENDURANCE TRAINING IN NON RESISTANCETRAINED FEMALES

The study investigated the effects of eight weeks of concurrent muscular strength and endurance resistance training of the non-dominant elbow flexors on muscular strength, endurance, and upper arm girths of previously non resistance-trained females. Subjects (n=12) were assigned to one of 3 training groups. These groups were Strength (S), Endurance (E), or Combined (C) with pre and post-training tests for arm girths, 1 RM preacher curl, maximal isometric torque, peak isokinetic torque at velocities of 30 and 90" s-', and total work during 25 continuous repetitions at 90"s.'. Significant increases in prepost strength and endurance occurred in both C and S groups, but not E, in the absence of any change in arm girth. Furthermore, C training produced equivalent gains in strength and endurance to the S and E groups, respectively

Cobimetinib and trametinib inhibit platelet MEK but do not cause platelet dysfunction

The MEK inhibitors cobimetinib and trametinib are used in combination with BRAF inhibitors to treat metastatic melanoma but increase rates of hemorrhage relative to BRAF inhibitors alone. Platelets express several members of the MAPK signalling cascade including MEK1 and MEK2 and ERK1 and ERK2 but their role in platelet function and haemostasis is ambiguous as previous reports have been contradictory. It is therefore unclear if MEK inhibitors might be causing platelet dysfunction and contributing to increased hemorrhage. In the present study we performed pharmacological characterisation of cobimetinib and trametinib in vitro to investigate potential for MEK inhibitors to cause platelet dysfunction. We report that whilst both cobimetinib and trametinib are potent inhibitors of platelet MEK activity, treatment with trametinib did not alter platelet function. Treatment with cobimetinib results in inhibition of platelet aggregation, integrin activation, alpha-granule secretion and adhesion but only at suprapharmacological concentrations. We identified that the inhibitory effects of high concentrations of cobimetinib are associated with off-target inhibition on Akt and PKC. Neither inhibitor caused any alteration in thrombus formation on collagen under flow conditions in vitro. Our findings demonstrate that platelets are able to function normally when MEK activity is fully inhibited, indicating MEK activity is dispensable for normal platelet function. We conclude that the MEK inhibitors cobimetinib and trametinib do not induce platelet dysfunction and are therefore unlikely to contribute to increased incidence of bleeding reported during MEK inhibitor therapy

Platelet signaling: a complex interplay between inhibitory and activatory networks

The role of platelets in hemostasis and thrombosis is dependent on a complex balance of activatory and inhibitory signaling pathways. Inhibitory signals released from the healthy vasculature suppress platelet activation in the absence of platelet receptor agonists. Activatory signals present at a site of injury initiate platelet activation and thrombus formation; subsequently, endogenous negative signaling regulators dampen activatory signals to control thrombus growth. Understanding the complex interplay between activatory and inhibitory signaling networks is an emerging challenge in the study of platelet biology and necessitates a systematic approach to utilize experimental data effectively. In this review, we will explore the key points of platelet regulation and signaling that maintain platelets in a resting state, mediate activation to elicit thrombus formation or provide negative feedback. Platelet signaling will be described in terms of key signaling molecules that are common to the pathways activated by platelet agonists and can be described as regulatory nodes for both positive and negative regulators. This article is protected by copyright. All rights reserved

Ca2+ waves coordinate purinergic receptor–evoked integrin activation and polarization

The integrin GPIIb/IIIa is highly abundant on the surface of platelets and can be activated by intracellular Ca2+ signaling in an “inside-out” manner to bind to the adhesive ligand fibrinogen. Bye et al. imaged intracellular Ca2+ signaling and fibrinogen binding events in primary rat megakaryocytes activated through the ADP-stimulated receptors P2Y1 and P2Y12. The authors found that signaling by both receptors was required for full integrin activation, which depended on P2Y1-stimulated Ca2+ signaling and P2Y12-stimulated activation of the kinase PI3K. In addition, fibrinogen binding became polarized in these cells in a manner dependent on the direction of ADP-stimulated Ca2+ waves