This paper provides an overview of the many different ways that light interacts with surfaces in the natural environment to provide useful information for visual perception. It begins with a discussion of how the concept of light has evolved over the course of human history. It then considers a wide variety of optical phenomena including Lambert's laws of illumination, the effects of microscopic surface structure on patterns of reflection, the bidirectional reflectance distribution function, the refraction of transmitted light, chromatic dispersion, thin film interference, sub-surface scattering, the Fresnel effects, indirect illumination from multiple reflections, caustics, and the structure of the light field.
View Article and Find Full Text PDFIn Western societies, social contingency, or prompt and meaningful back-and-forth exchanges between infant and caregiver, is a powerful feature of the early language environment. Research suggests that infants with better attentional skills engage in more social contingency during interactions with adults and, in turn, social contingency supports infant attention. This reciprocity is theorized to build infant language skills as the adult capitalizes on and extends the infant's attention during socially contingent interactions.
View Article and Find Full Text PDFClin Transl Gastroenterol
March 2024
Introduction: Isolated case reports and case series have linked the use of sevelamer to severe gastrointestinal (GI) inflammation and perforation among patients with end-stage renal disease.
Methods: In this study, we identified 12 cases of biopsy-proven sevelamer-induced gastrointestinal disease from a large urban community hospital over the course of 5 years. We described baseline characteristics, sites and types of injury, histological findings, timing and dosing of sevelamer initiation compared with symptom onset, and in a smaller subset, endoscopic resolution post drug cessation.
Purpose: The COVID-19 pandemic had a profound negative effect on mental health worldwide. The hospital emergency department plays a pivotal role in responding to mental health crises. Understanding data trends relating to hospital emergency department usage is beneficial for service planning, particularly around preparing for future pandemics.
View Article and Find Full Text PDFObjective: To determine whether differences exist for older persons presenting to Emergency Departments (EDs) with lower back pain (LBP) in terms of management, health service resource use and cost when compared to younger patients with LBP.
Methods: Retrospective analysis of routinely collected electronic medical record data from January 2015 to July 2021. Data from 11,098 adults presenting with LBP to two large regional Australian EDs were analysed over a 5-year period.
Socioeconomic status (SES) is a well-established predictor of individual differences in childhood language and cognitive functioning, including executive functions such as working memory. In infancy, intersensory processing-selectively attending to properties of events that are redundantly specified across the senses at the expense of non-redundant, irrelevant properties-also predicts language development. Our recent research demonstrates that individual differences in intersensory processing in infancy predict a variety of language outcomes in childhood, even after controlling for SES.
View Article and Find Full Text PDFResearch demonstrates that contingent and appropriate maternal responsiveness to infant requests and bids for attention leads to better language outcomes. Research also indicates that infants who are less distracted by irrelevant competing stimulation and attend efficiently to audiovisual social events (e.g.
View Article and Find Full Text PDFRecent research has demonstrated that individual differences in infant attention to faces and voices of women speaking predict language outcomes in childhood. These findings have been generated using two new audiovisual attention assessments appropriate for infants and young children, the Multisensory Attention Assessment Protocol (MAAP) and the Intersensory Processing Efficiency Protocol (IPEP). The MAAP and IPEP assess three basic attention skills (sustaining attention, shifting/disengaging, intersensory matching), as well as distractibility, deployed in the context of naturalistic audiovisual social (women speaking English) and nonsocial events (objects impacting a surface).
View Article and Find Full Text PDFA new source of information is proposed for the perception of three-dimensional (3D) shape from shading that identifies surface concavities from the curvature of the luminance field. Two experiments measured the abilities of human observers to identify concavities on smoothly curved shaded surfaces depicted with several different patterns of illumination and several different material properties. Observers were required to identify any apparent concavities along designated cross sections of the depicted objects and to mark each concavity with an adjustable dot.
View Article and Find Full Text PDFIntersensory processing of social events (e.g., matching sights and sounds of audiovisual speech) is a critical foundation for language development.
View Article and Find Full Text PDFChildren with autism spectrum disorders (ASD) show atypical attention, particularly for social events. The new Multisensory Attention Assessment Protocol (MAAP) assesses fine-grained individual differences in attention disengagement, maintenance, and audiovisual matching for social and nonsocial events. We investigated the role of competing stimulation on attention, and relations with language and symptomatology in children with ASD and typical controls.
View Article and Find Full Text PDFInt J Risk Saf Med
December 2022
Background: The Nightingale North West (NNW) was a UK temporary field hospital set up during the COVID-19 pandemic. Policies and standard operating procedures were undeveloped. Visitors were permitted only in exceptional circumstances, resulting in heightened anxiety for patients and next of kin (NOK).
View Article and Find Full Text PDFParent language input is a well-established predictor of child language development. Multisensory attention skills (MASks; intersensory matching, shifting and sustaining attention to audiovisual speech) are also known to be foundations for language development. However, due to a lack of appropriate measures, individual differences in these skills have received little research focus.
View Article and Find Full Text PDFYu, Todd, and Petrov (2021) and Yu, Petrov, and Todd (2021) investigated failures of shape constancy that occur when objects are viewed stereoscopically at different distances. Although this result has been reported previously with simple objects such as pyramids or cylinders, we examined more complex objects with bilateral symmetry to test the claim by Li, Sawada, Shi, Kwon, and Pizlo (2011) that the perception of those objects is veridical. Sawada and Pizlo (2022) offer several criticisms of our experiments, but they seem to suggest that the concept of shape is defined by what is computable by their model.
View Article and Find Full Text PDFIn early 2020, in-person data collection dramatically slowed or was completely halted across the world as many labs were forced to close due to the COVID-19 pandemic. Developmental researchers who assess looking time (especially those who rely heavily on in-lab eye-tracking or live coding techniques) were forced to re-think their methods of data collection. While a variety of remote or online platforms are available for gathering behavioral data outside of the typical lab setting, few are specifically designed for collecting and processing looking time data in infants and young children.
View Article and Find Full Text PDFShape is an interesting property of objects because it is used in ordinary discourse in ways that seem to have little connection to how it is typically defined in mathematics. The present article describes how the concept of shape can be grounded within Euclidean and non-Euclidean geometry and also to human perception. It considers the formal methods that have been proposed for measuring the differences among shapes and how the performance of those methods compares with shape difference thresholds of human observers.
View Article and Find Full Text PDFBackground: Emergency department and urgent care (ED/UC) visits for common conditions can be more expensive with less continuity than office care provided by primary care physicians.
Methods: We used quality-improvement methods to enhance telephone triage for pediatric patients by adding additional "Phone First" services including: 1) enhanced office-hours telephone triage and advice with available same-day appointments, 2) follow-up calls to parents of children self-referred to an ED/UC, and 3) parent education to telephone the office for advice prior to seeking acute care. We hypothesized that enhanced office services would reduce ED/UC utilization and cost.
The total sugarcane (Saccharum L.) production has increased worldwide; however, the rate of growth is lower compared with other major crops, mainly due to a plateauing of genetic gain. Genomic selection (GS) has proven to substantially increase the rate of genetic gain in many crops.
View Article and Find Full Text PDFA single experiment is reported that measured the apparent stereoscopic shapes of symmetric and asymmetric objects at different viewing distances. The symmetric stimuli were specifically designed to satisfy the minimal conditions for computing veridical shape from symmetry. That is to say, they depicted complex, bilaterally symmetric, plane-faced polyhedra whose symmetry planes were oriented at an angle of 45° relative to the line of sight.
View Article and Find Full Text PDFTwo shape matching experiments examined the effects of viewing distance and object size on observers' judgments of 3D metric shape under binocular viewing. Unlike previous studies on this topic, the stimuli were specifically designed to satisfy the minimal conditions for computing veridical shape from symmetry. Concretely, the stimuli were complex, mirror-symmetric polyhedra whose symmetry planes were oriented at an angle of 45o relative to the line of sight in a shape-matching task.
View Article and Find Full Text PDFThe NAMWEZA intervention was implemented, using a ten-session group format, to build skills targeting psychosocial vulnerabilities and enhancing HIV prevention among people living with HIV (PLH) and their social networks. The overall goal of this intervention is to improve psychological wellbeing and reduce HIV risk behaviours. These analyses aim to describe the barriers and facilitators of implementing the NAMWEZA intervention from the perspective of participants and trained peer group facilitators.
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