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Previous studies reported that adolescents with a sport-related concussion history showed prolonged visuomotor deficits during an eye-hand decoupling task until around 1.5-2 years post-event. The present study expands this work, examining whether such deficits do or do not emerge when testing individuals in young adulthood, i.e. later post-event. Twenty-one non-athlete college students with sport-related concussion history from adolescence (CH

Visually guided reaching precision and accuracy depend on the level of coupling between movements of the eyes and hand. In the present study, participants performed central fixations and either saccadic or smooth pursuit eye movements during fast and accurate reaching tasks involving eye–hand coupling and decoupling to better understand type of eye movement influence over upper limb control. Some eye–hand coupling and decoupling tasks also included hand reversals, where the hand moves away from the target to direct a cursor toward the target to account for various levels of hand–cursor and eye–cursor coupling. Regardless of eye-movement type, eye–hand–cursor coupling produced an endpoint accuracy advantage over decoupling. Use of hand reversal decreased peak speed and increased response time of the hand, whether considering fixation or a given eye movement. Use of smooth pursuit slowed hand movements relative to saccades, yet improved endpoint accuracy. Compared to central fixations, using smooth pursuit also slowed hand movements, while using saccades decreased, thus improved, hand reaction times. Data suggest an advantage, when using smooth pursuit to track the hand movement for the greatest endpoint accuracy, an advantage when using saccades for the fastest movements, and an eye–hand coupling advantage when using saccades for the shortest reactions. Researchers should provide clear eye-movement instructions for participants and/or monitor the eyes when assessing similar upper limb control to account for possible differences in eye movements used. Moreover, the type of eye movement chosen for participants should correspond to the primary goal of the task.

The presence of complex organic molecules (COMs) in a variety of solar system objects has prompted various theories regarding their origins. This paper reports on a series of proton, electron, and ...

The present study expands previous work that reported eye-hand decoupling (EHD) deficits in young adults with concussion history from adolescence. Here, we examine whether these deficits in movement planning (i.e., larger initial direction error) can be linked to difficulties with adapting to new task constraints or meeting ongoing task demands. Data from 21 young adults with concussion history from adolescence (CH) and 20 no history controls (NoH) were analyzed. All participants (Mean = 21 yrs.) performed two eye-hand coordination tasks, a standard task with vision and motor action in alignment, and an EHD task with eye- and hand movement direction spatially decoupled, with twenty trials per task condition. The re-analysis focused on the EHD condition as deficits were found for this task only in prior work. Trials were split into 5 blocks (trial 1-4, 5-8, 9-12, 13-16, 17-20), which included one movement to each of four target directions, and were analyzed across blocks and groups. The CH group had a larger initial direction error during blocks 1-2 but not in blocks 3-5. Our findings suggest that young adults with concussion history from adolescence can have difficulty with adapting to new task constraints associated with complex skill performance during a short series of trials.

Visually guided reaching precision and accuracy depend on the level of coupling between movements of the eyes and hand. In the present study, participants performed central fixations and either saccadic or smooth pursuit eye movements during fast and accurate reaching tasks involving eye-hand coupling and decoupling to better understand type of eye movement influence over upper limb control. Some eye-hand coupling and decoupling tasks also included hand reversals, where the hand moves away from the target to direct a cursor toward the target to account for various levels of hand-cursor and eye-cursor coupling. Regardless of eye-movement type, eye-hand-cursor coupling produced an endpoint accuracy advantage over decoupling. Use of hand reversal decreased peak speed and increased response time of the hand, whether considering fixation or a given eye movement. Use of smooth pursuit slowed hand movements relative to saccades, yet improved endpoint accuracy. Compared to central fixations, using smooth pursuit also slowed hand movements, while using saccades decreased, thus improved, hand reaction times. Data suggest an advantage, when using smooth pursuit to track the hand movement for the greatest endpoint accuracy, an advantage when using saccades for the fastest movements, and an eye-hand coupling advantage when using saccades for the shortest reactions. Researchers should provide clear eye-movement instructions for participants and/or monitor the eyes when assessing similar upper limb control to account for possible differences in eye movements used. Moreover, the type of eye movement chosen for participants should correspond to the primary goal of the task.

Supervisory Control and Data Acquisition (SCADA) systems have been designed with the assumption that the system would run within a closed environment. They have only generated concerns for security issues that may appear during system deployment, and there are no clear methods to assess security threats when considered. Recent technological and economic trends have driven SCADA systems from serial communication networks to networks based on TCP/IP. This exposes legacy SCADA systems to new security threats they were not designed to defend against. This work examines the viability of machine learning techniques in detecting new security threats specific to SCADA systems and the Modbus protocol. Machine learning-based anomaly detection algorithms were used to detect malicious traffic in a generated dataset of Remote Terminal Unit (RTU) communications using the Modbus protocol. The implemented algorithms are Support Vector Machines, decision trees, k-nearest neighbors, and k-means clustering. While the algorithms performed well overall, Support Vector Machine, Decision Trees, and K-nearest Neighbors algorithms had the best performance with individual attack types. K-means clustering did not perform satisfactorily with specific attack types.

Magnetic skyrmions are topologically stable vortex-like spin structures that are promising for next generation information storage applications. Materials that host magnetic skyrmions, such as MnSi and FeGe with the noncentrosymmetric cubic B20 crystal structure, have been shown to stabilize skyrmions upon nanostructuring. Here, we report a chemical vapor deposition method to selectively grow nanowires (NWs) of cubic FeGe out of three possible FeGe polymorphs for the first time using finely ground particles of cubic FeGe as seeds. X-ray diffraction and transmission electron microscopy (TEM) confirm that these micron-length NWs with ∼100 nm to 1 μm diameters have the cubic B20 crystal structure. Although Fe13Ge8 NWs are also formed, the two types of NWs can be readily differentiated by their faceting. Lorentz TEM imaging of the cubic FeGe NWs reveals a skyrmion lattice phase under small applied magnetic fields (∼0.1 T) at 233 K, a skyrmion chain state at lower temperatures (95 K) and under high magnetic fi...

This research develops and tests a new quality construct, SNS quality, and introduces SNSQUAL, a social networking site (SNS) quality model. SNSQUAL contains five independent dimensions that positively correlate with social media quality.

The following interview with Mr. Michael Holcomb, Manager of Enterprise Database and Intelligence Reporting at Caesars Entertainment Corporation, examines big data and analytics at Caesars from an information technology management perspective. Business intelligence (BI) and analytics are essential to this enormous customer-focused enterprise, where it guides decisions in virtually every aspect of the business. The interview describes how Caesars has consolidated its information and analytical processes into a single, integrated source that is accessed by BI experts across the company. It also discusses expectations for continued evolution of analytics as a critical success factor.

When engaging in a visual-aided task, decision making becomes a multifaceted process that includes the factors usability, visual design aesthetics, emotion and cognitive load. We develop and test a decision-making model by measuring usability, visual design aesthetics, emotion and cognitive load within a structural equation model (SEM). This research model is the first to combine these constructs to study the relationships between usability, design aesthetics, emotion and cognitive load as they relate to post-task confidence and task performance. Results show that usability, visual design, emotion and cognitive load significantly affect the user’s post-decision confidence and performance. The implications are that well-designed visuals added to a decision-making process model induce positive effects, because cognitive efficiency increases resulting in enhanced task confidence and performance.

The increasing use of data visualization for displaying information in a transdisciplinary environment raises issues about client information seeking in the decision-making processes. Field experts and individuals with high confidence tend to seek less information for their decisions than non-experts and individuals who are less confident. This work fills a gap about the effect of the information display format, visual or nonvisual, upon the client’s decision. In the context of data visualization and confirmation bias, this work provides needed research on computer aided information seeking in a decision-making, informing environment. Guided by the theories of confirmation bias and cognitive fit, we propose and test a model that investigates the impact of apriori decision confidence on seeking more information and information usefulness. Findings indicate that both information presentation type and confirmation bias affect the decision process of the information seeker. Findings also indicate that overall, the higher the confidence, the less likely users will find disconfirming evidence useful.

To successfully operate a photovoltaic (PV) array system in space requires planning and testing to account for the effects of the space environment. It is critical to understand space environment interactions not only on the PV components, but also the array substrate materials, wiring harnesses, connectors, and protection circuitry (e.g. blocking diodes). Key elements of the space environment which must be accounted for in a PV system design include: Solar Photon Radiation, Charged Particle Radiation, Plasma, and Thermal Cycling. While solar photon radiation is central to generating power in PV systems, the complete spectrum includes short wavelength ultraviolet components, which photo-ionize materials, as well as long wavelength infrared which heat materials. High energy electron radiation has been demonstrated to significantly reduce the output power of III–V type PV cells; and proton radiation damages material surfaces - often impacting coverglasses and antireflective coatings. Plasma environments influence electrostatic charging of PV array materials, and must be understood to ensure that long duration arcs do not form and potentially destroy PV cells. Thermal cycling impacts all components on a PV array by inducing stresses due to thermal expansion and contraction. Given such demanding environments, and the complexity of structures and materials that form a PV array system, mission success can only be ensured through realistic testing in the laboratory. NASA's Marshall Space Flight Center has developed a broad space environment test capability to allow PV array designers and manufacturers to verify their system's integrity and avoid costly on-orbit failures. The Marshall Space Flight Center test capabilities are available to government, commercial, and university customers. Test solutions are tailored to meet the customer's needs, and can include performance assessments, such as flash testing in the case of PV cells.

There has been a perception in both industry and in academia that mainframe skills are obsolete. As a result, there has been a decline in curricula addressing these skills. However, recent evidence shows that many organizations are still actively supporting mainframe technologies and report a need for students graduating in information technology to be trained in those skills, especially as much of their current mainframe workforce moves toward retirement. This paper examines the question of what motivates students to acquire mainframe skills. To do so, this research is investigates IBM's Master the Mainframe contest, a competition that attempts to engender enthusiasm for acquiring mainframe skills and ensure an adequate supply of such skills to organizations relying on them.