Development of a Virtual Laboratory for the Study of Complex Human Behavior

The study of human perception has evolved from examining simple tasks executed in reduced laboratory conditions to the examination of complex, real-world behaviors. Virtual environments represent the next evolutionary step by allowing full stimulus control and repeatability for human subjects, and a testbed for evaluating models of human behavior. Visual resolution varies dramatically across the visual field, dropping orders of magnitude from central to peripheral vision. Humans move their gaze about a scene several times every second, projecting taskcritical areas of the scene onto the central retina. These eye movements are made even when the immediate task does not require high spatial resolution. Such “attentionally-driven” eye movements are important because they provide an externally observable marker of the way subjects deploy their attention while performing complex, real-world tasks. Tracking subjects’ eye movements while they perform complex tasks in virtual environments provides a window into perception. In addition to the ability to track subjects’ eyes in virtual environments, concurrent EEG recording provides a further indicator of cognitive state. We have developed a virtual reality laboratory in which head-mounted displays (HMDs) are instrumented with infrared video-based eyetrackers to monitor subjects’ eye movements while they perform a range of complex tasks such as driving, and manual tasks requiring careful eye-hand coordination. A go-kart mounted on a 6DOF motion platform provides kinesthetic feedback to subjects as they drive through a virtual town; a dual-haptic interface consisting of two SensAble Phantom extended range devices allows free motion and realistic force-feedback within a 1^3 m volume (Refer to PDF file for exact formulas)

Patient-initiated second medical consultations: patient characteristics and motivating factors, impact on care and satisfaction: A systematic review

Objectives: To review the characteristics and motivations of patients seeking second opinions, and the impact of such opinions on patient management, satisfaction, and cost-effectiveness. Data sources: Embase, Medline, PsycINFO and HMIC databases. Study design: A systematic literature search was performed for terms related to second opinion and patient characteristics. Study quality was assessed using the National Institutes of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Data collection / Extraction methods: We included articles focused on patient-initiated second opinions, which provided quantitative data on their impact on diagnosis, treatment, prognosis or patient satisfaction, described the characteristics or motivating factors of patients who initiated a second opinion, or the cost-effectiveness of patient-initiated second opinions. Principal findings: Thirty-one articles were included in the review. 27 studies considered patient characteristics, 18 patient motivating factors, 10 patient satisfaction, and 17 clinical agreement between the first and second opinion. Seeking a second opinion was more common in women, middle age patients, more educated patients; and in people having a chronic condition, with higher income or socioeconomic status or living in central urban areas. Patients seeking a second opinion sought to gain more information or reassurance about their diagnosis or treatment. While many second opinions confirm the original diagnosis or treatment, discrepancies in opinions had a potential major impact on patient outcomes in up to 58% of cases. No studies reporting on the cost-effectiveness of patient initiated second opinions. Conclusions: Seeking a second opinion was more common in women, middle-age patients, and more educated patients, and in people having a chronic condition, with higher income or socioeconomic status or living in central urban areas. Patients seeking a second opinion sought to gain more information or reassurance about their diagnosis or treatment

The climate sensitivity of carbon, timber, and species richness covaries with forest age in boreal–temperate North America

Climate change threatens the provisioning of forest ecosystem services and biodiversity (ESB). The climate sensitivity of ESB may vary with forest development from young to old-growth conditions as structure and composition shift over time and space. This study addresses knowledge gaps hindering implementation of adaptive forest management strategies to sustain ESB. We focused on a number of ESB indicators to (a) analyze associations among carbon storage, timber growth rate, and species richness along a forest development gradient; (b) test the sensitivity of these associations to climatic changes; and (c) identify hotspots of climate sensitivity across the boreal–temperate forests of eastern North America. From pre-existing databases and literature, we compiled a unique dataset of 18,507 forest plots. We used a full Bayesian framework to quantify responses of nine ESB indicators. The Bayesian models were used to assess the sensitivity of these indicators and their associations to projected increases in temperature and precipitation. We found the strongest association among the investigated ESB indicators in old forests (\u3e170 years). These forests simultaneously support high levels of carbon storage, timber growth, and species richness. Older forests also exhibit low climate sensitivity of associations among ESB indicators as compared to younger forests. While regions with a currently low combined ESB performance benefitted from climate change, regions with a high ESB performance were particularly vulnerable to climate change. In particular, climate sensitivity was highest east and southeast of the Great Lakes, signaling potential priority areas for adaptive management. Our findings suggest that strategies aimed at enhancing the representation of older forest conditions at landscape scales will help sustain ESB in a changing world

Reassessing China’s Higher Education Development: A Focus on Academic Culture

During the past three and a half decades, China has been progressing in higher education in a surprisingly dramatic manner, evidenced especially by scientific publications and sheer numbers of graduates. Such a fact has national, regional and global implications. China’s higher education development and its future directions are now placed highly on the research agendas of many from various parts of the world. Unlike the general acknowledgment of China’s achievements, assessment of the future development of China’s higher education is wide open to question. To some, Chinese universities are on a trajectory to become “world-class” and China’s high-fliers challenge Western supremacy. To others, China’s notion of “world-class” status has been largely imitative. Pumping resources into universities will only lead to diminishing returns as Chinese culture and practices will act as a brake to the pursuit of academic excellence. An increasing deal of attention has been paid to where China will be located in a global higher education landscape and in what shape. Based on the author’s long-standing professional observation and recent empirical studies, this article assesses China’s higher education development, with a particular focus on the challenges brought forward by academic culture. It interrogates China’s pride of the idea that Chinese universities are not willing to assume that Western models define excellence, and asks how far Chinese universities could move within their current development model.postprin

The programming of sequences of saccades

Saccadic eye movements move the high-resolution fovea to point at regions of interest. Saccades can only be generated serially (i.e., one at a time). However, what remains unclear is the extent to which saccades are programmed in parallel (i.e., a series of such moments can be planned together) and how far ahead such planning occurs. In the current experiment, we investigate this issue with a saccade contingent preview paradigm. Participants were asked to execute saccadic eye movements in response to seven small circles presented on a screen. The extent to which participants were given prior information about target locations was varied on a trial-by-trial basis: participants were aware of the location of the next target only, the next three, five, or all seven targets. The addition of new targets to the display was made during the saccade to the next target in the sequence. The overall time taken to complete the sequence was decreased as more targets were available up to all seven targets. This was a result of a reduction in the number of saccades being executed and a reduction in their saccade latencies. Surprisingly, these results suggest that, when faced with a demand to saccade to a large number of target locations, saccade preparation about all target locations is carried out in paralle

The epistemological model of disability, and its role in understanding passive exclusion in eighteenth and nineteenth century protestant educational asylums

This article examines how the process of constructing knowledge on impairment has affected the institutional construction of an ethic of disability. Its primary finding is that the process of creating knowledge in a number of historical contexts was influenced more by traditions and the biases of philosophers and educators in order to signify moral and intellectual superiority, than by a desire to improve the lives of disabled people through education. The article illustrates this epistemological process in a case study of the development of Protestant asylums in the latter years of the nineteenth century

CMIP5 climate model analyses: Climate extremes in the United States

Given the increases in spatial resolution and other improvements in climate modeling capabilities over the last decade since the CMIP3 simulations were completed, CMIP5 provides a unique opportunity to assess scientific understanding of climate variability and change over a range of historical and future conditions. With participation from over 20 modeling groups and more than 40 global models, CMIP5 represents the latest and most ambitious coordinated international climate model intercomparison exercise to date. Observations dating back to 1900 show that the temperatures in the twenty-first century have the largest spatial extent of record breaking and much above normal mean monthly maximum and minimum temperatures. The 20-yr return value of the annual maximum or minimum daily temperature is one measure of changes in rare temperature extremes

Emissions pathways, climate change, and impacts on California

The magnitude of future climate change depends substantially on the greenhouse gas emission pathways we choose. Here we explore the implications of the highest and lowest Intergovernmental Panel on Climate Change emissions pathways for climate change and associated impacts in California. Based on climate projections from two state-of-the-art climate models with low and medium sensitivity (Parallel Climate Model and Hadley Centre Climate Model, version 3, respectively), we find that annual temperature increases nearly double from the lower B1 to the higher A1fi emissions scenario before 2100. Three of four simulations also show greater increases in summer temperatures as compared with winter. Extreme heat and the associated impacts on a range of temperature-sensitive sectors are substantially greater under the higher emissions scenario, with some interscenario differences apparent before midcentury. By the end of the century under the B1 scenario, heatwaves and extreme heat in Los Angeles quadruple in frequency while heat-related mortality increases two to three times; alpine subalpine forests are reduced by 50–75%; and Sierra snowpack is reduced 30–70%. Under A1fi, heatwaves in Los Angeles are six to eight times more frequent, with heat-related excess mortality increasing five to seven times; alpine subalpine forests are reduced by 75–90%; and snowpack declines 73–90%, with cascading impacts on runoff and streamflow that, combined with projected modest declines in winter precipitation, could fundamentally disrupt California’s water rights system. Although interscenario differences in climate impacts and costs of adaptation emerge mainly in the second half of the century, they are strongly dependent on emissions from preceding decades