Increasing difficulty but not decreasing performance: maintained interception with increments in visual blur

Conference Theme: Meeting New Challenges and Bridging Cultural Gaps in Sport and Exercise PsychologyINTRODUCTION: In an earlier study on the relationship between visual blur and interceptive skill (Mann, Ho, De Souza, Watson, & Taylor, 2007) it was observed that interceptive performance can be maintained despite the introduction of significant refractive visual blur. Mann et al. found that contact lenses simulating legally-blind levels of short-sightedness were required (6/60 or 20/200 acuity) before any subjectively assessed decrease in skilled performance could be measured when intercepting balls pitched by a projection machine in the sport of cricket. Several of the participants reported a preference for taking part with low levels of visual blur as a means of focusing concentration and visual attention, raising the possibility that rather than decreasing performance, training with blurred vision may provide an opportunity to enhance skill acquisition. The aim of this study was to extend the protocol of Mann et …postprin

Gaze-contingent training enhances perceptual skill acquisition.

The purpose of this study was to determine whether decision-making skill in perceptual-cognitive tasks could be enhanced using a training technique that impaired selective areas of the visual field. Recreational basketball players performed perceptual training over 3 days while viewing with a gaze-contingent manipulation that displayed either (a) a moving window (clear central and blurred peripheral vision), (b) a moving mask (blurred central and clear peripheral vision), or (c) full (unrestricted) vision. During the training, participants watched video clips of basketball play and at the conclusion of each clip made a decision about to which teammate the player in possession of the ball should pass. A further control group watched unrelated videos with full vision. The effects of training were assessed using separate tests of decision-making skill conducted in a pretest, posttest, and 2-week retention test. The accuracy of decision making was greater in the posttest than in the pretest for all three intervention groups when compared with the control group. Remarkably, training with blurred peripheral vision resulted in a further improvement in performance from posttest to retention test that was not apparent for the other groups. The type of training had no measurable impact on the visual search strategies of the participants, and so the training improvements appear to be grounded in changes in information pickup. The findings show that learning with impaired peripheral vision offers a promising form of training to support improvements in perceptual skill

The contributions of central and peripheral vision to expertise in basketball: How blur helps to provide a clearer picture

The main purpose of this study was to examine the relative roles of central and peripheral vision when performing a dynamic forced-choice task. We did so by using a gaze-contingent display with different levels of blur in an effort to (a) test the limit of visual resolution necessary for information pick-up in each of these sectors of the visual field and, as a result, to (b) develop a more natural means of gaze-contingent display using a blurred central or peripheral visual field. The expert advantage seen in usual whole field visual presentation persists despite surprisingly high levels of impairment to central or peripheral vision. Consistent with the well-established central/peripheral differences in sensitivity to spatial frequency, high levels of blur did not prevent better-than-chance performance by skilled players when peripheral information was blurred, but they did affect response accuracy when impairing central vision. Blur was found to always alter the pattern of eye movements before it decreased task performance. The evidence accumulated across the 4 experiments provides new insights into several key questions surrounding the role that different sectors of the visual field play in expertise in dynamic, time-constrained tasks

Oyster Reef Restoration: Convergence Of Harvest And Conservation Strategies

Oyster reef restoration, protection, and construction are important to meeting harvest, water quality, and fish habitat goals. However, the strategies needed to achieve harvest and conservation goals have often been considered to be at odds. We argue that these goals are. in fact, compatible and that the same strategies will promote a sustainable harvest of the resource, increased filtration of estuarine waters, and increased provision of structured habitat for finfish, crabs, and other organisms that utilize oyster reefs or receive benefit indirectly from them. Creation or designations of unharvested sites (refuge sites) are key components of these strategies. Unharvested reefs have the potential to provide vertical relief, which is typically destroyed by harvest practices, to act as a source of larvae, which potentially increases the supply of harvestable oysters, and to protect those individuals most likely to have some resistance to disease. Furthermore. proper monitoring and design of refuge and restoration efforts are critical to providing information needed to improve the success of future restoration efforts, and will simultaneously enhance the basic information needed to understand the ecology of oysters and their role in estuarine and coastal systems

Analysis of surface roughness morphology with TRIZ methodology in automotive electrical contacts: Design against third body fretting-corrosion

Electrical connectors for motor vehicles are essential for the safe and efficient operation of a vehicle. However, their durability is limited by fretting induced corrosion. This type of surface damage is observed between two interconnected surfaces exposed to vibration and temperature variations. Such conditions occur during normal vehicle operation and cause two parts of an electrical contact to move at high frequency and with a small amplitude of movement relative to each other. This damages both surfaces, creates wear particles and then oxidizes them in the air. This causes an oxide layer to form at the interface, isolating the two surfaces and increasing the electrical resistance, resulting in contact failure. This study shows how the service life of electrical contacts can be extended by a surface design approach that controls the metal interface and ensures low contact resistance. The approach combines surface morphology with the progressive process of interfacial oxidation. A strong relationship between surface roughness and electrical contact resistance was observed and is elucidated in this study. Theory of Inventive Problems Solving (TRIZ) was used to identify surface texturing as a viable option to increase durability of automotive electrical connectors

Difficult at dusk? Illuminating the debate on cricket ball visibility

Objectives: Investigate the visibility of new and old red, white and pink cricket balls under lighting and background conditions experienced during a day–night cricket match. Design: We modelled the luminance contrast signals available for a typical observer for a ball against backgrounds in a professional cricket ground, at different times of day. Methods: Spectral reflectance (light reflected as a function of wavelength) was derived from laboratory measurements of new and old red, white and pink balls. We also gathered spectral measurements from backgrounds (pitch, grass, sightscreens, crowd, sky) and spectral illuminance during a day–night match (natural afternoon light, through dusk to night under floodlights) from Lord's Cricket Ground (London, UK). The luminance contrast of the ball relative to the background was calculated for each combination of ball, time of day, and background surface. Results: Old red and old pink balls may offer little or no contrast against the grass, pitch and crowd. New pink balls can also be of low contrast against the crowd at dusk, as can pink and white balls (of any age) against the sky at dusk. Conclusions: Reports of difficulties with visibility of the pink ball are supported by our data. However, our modelling also shows that difficulties with visibility may also be expected under certain circumstances for red and white balls. The variable conditions in a cricket ground and the changing colour of an ageing ball make maintaining good visibility of the ball a challenge when playing day–night matches

Inhibition of Progenitor Dendritic Cell Maturation by Plasma from Patients with Peripartum Cardiomyopathy: Role in Pregnancy-associated Heart Disease

Dendritic cells (DCs) play dual roles in innate and adaptive immunity based on their functional maturity, and both innate and adaptive immune responses have been implicated in myocardial tissue remodeling associated with cardiomyopathies. Peripartum cardiomyopathy (PPCM) is a rare disorder which affects women within one month antepartum to five months postpartum. A high occurrence of PPCM in central Haiti (1 in 300 live births) provided the unique opportunity to study the relationship of immune activation and DC maturation to the etiology of this disorder. Plasma samples from two groups (n = 12) of age- and parity-matched Haitian women with or without evidence of PPCM were tested for levels of biomarkers of cardiac tissue remodeling and immune activation. Significantly elevated levels of GM-CSF, endothelin-1, proBNP and CRP and decreased levels of TGF- were measured in PPCM subjects relative to controls. Yet despite these findings, in vitro maturation of normal human cord blood derived progenitor dendritic cells (CBDCs) was significantly reduced (p < 0.001) in the presence of plasma from PPCM patients relative to plasma from post-partum control subjects as determined by expression of CD80, CD86, CD83, CCR7, MHC class II and the ability of these matured CBDCs to induce allo-responses in PBMCs. These results represent the first findings linking inhibition of DC maturation to the dysregulation of normal physiologic cardiac tissue remodeling during pregnancy and the pathogenesis of PPCM

Lessons Learned From Efforts To Restore Oyster Populations In Maryland And Virginia, 1990 To 2007

A century-long decline of the fishery for the Eastern oyster Crassostrea virginica (Gmelin, 1791) in Maryland and Virginia stimulated numerous efforts by federal, state, and nongovernmental agencies to restore oyster populations, with limited success. To learn from recent efforts, we analyzed records of restoration and monitoring activities undertaken between 1990 and 2007 by 12 such agencies. Of the 1,037 oyster bars (reefs, beds, or grounds) for which we obtained data, 43% experienced both restoration and monitoring, with the remaining experiencing either restoration or monitoring only. Restoration activities involved adding substrate (shell), transplanting hatchery or wild seed (juvenile oysters), bar cleaning, and bagless dredging. Of these, substrate addition and transplanting seed were common actions, with bar cleaning and bagless dredging relatively uncommon. Limited monitoring efforts, a lack of replicated postrestoration sampling, and the effects of harvest on some restored bars hinders evaluations of the effectiveness of restoration activities. Future restoration activities should have clearly articulated objectives and be coordinated among agencies and across bars, which should also be off limits to fishing. To evaluate restoration efforts, experimental designs should include replication, quantitative sampling, and robust sample sizes, supplemented by pre- and postrestoration monitoring

Suicide ideation of individuals in online social networks

Suicide explains the largest number of death tolls among Japanese adolescents in their twenties and thirties. Suicide is also a major cause of death for adolescents in many other countries. Although social isolation has been implicated to influence the tendency to suicidal behavior, the impact of social isolation on suicide in the context of explicit social networks of individuals is scarcely explored. To address this question, we examined a large data set obtained from a social networking service dominant in Japan. The social network is composed of a set of friendship ties between pairs of users created by mutual endorsement. We carried out the logistic regression to identify users' characteristics, both related and unrelated to social networks, which contribute to suicide ideation. We defined suicide ideation of a user as the membership to at least one active user-defined community related to suicide. We found that the number of communities to which a user belongs to, the intransitivity (i.e., paucity of triangles including the user), and the fraction of suicidal neighbors in the social network, contributed the most to suicide ideation in this order. Other characteristics including the age and gender contributed little to suicide ideation. We also found qualitatively the same results for depressive symptoms.Comment: 4 figures, 9 table