Quantitative assessment of intrinsic noise for visually guided behaviour in zebrafish

Supported by Royal Society of London (University Research Fellowship), Medical Research Council (New Investigator Research Grant) and CNRS.Peer reviewedPostprin

Visual Detection Under Uncertainty Operates Via an Early Static, Not Late Dynamic, Non-Linearity

Signals in the environment are rarely specified exactly: our visual system may know what to look for (e.g., a specific face), but not its exact configuration (e.g., where in the room, or in what orientation). Uncertainty, and the ability to deal with it, is a fundamental aspect of visual processing. The MAX model is the current gold standard for describing how human vision handles uncertainty: of all possible configurations for the signal, the observer chooses the one corresponding to the template associated with the largest response. We propose an alternative model in which the MAX operation, which is a dynamic non-linearity (depends on multiple inputs from several stimulus locations) and happens after the input stimulus has been matched to the possible templates, is replaced by an early static non-linearity (depends only on one input corresponding to one stimulus location) which is applied before template matching. By exploiting an integrated set of analytical and experimental tools, we show that this model is able to account for a number of empirical observations otherwise unaccounted for by the MAX model, and is more robust with respect to the realistic limitations imposed by the available neural hardware. We then discuss how these results, currently restricted to a simple visual detection task, may extend to a wider range of problems in sensory processing

Global Properties of Natural Scenes Shape Local Properties of Human Edge Detectors

Visual cortex analyzes images by first extracting relevant details (e.g., edges) via a large array of specialized detectors. The resulting edge map is then relayed to a processing pipeline, the final goal of which is to attribute meaning to the scene. As this process unfolds, does the global interpretation of the image affect how local feature detectors operate? We characterized the local properties of human edge detectors while we manipulated the extent to which the statistical properties of the surrounding image conformed to those encountered in natural vision. Although some aspects of local processing were unaffected by contextual manipulations, we observed significant alterations in the operating characteristics of the detector which were solely attributable to a higher-level semantic interpretation of the scene, unrelated to lower-level aspects of image statistics. Our results suggest that it may be inaccurate to regard early feature detectors as operating outside the domain of higher-level vision; although there is validity in this approach, a full understanding of their properties requires the inclusion of knowledge-based effects specific to the statistical regularities found in the natural environment

Action perception is intact in autism spectrum disorder

Date of Acceptance:10/11/2014. Copyright © 2015 the authors 0270-6474/15/351849-09$15.00/0. Copyright of all material published in The Journal of Neuroscience remains with the authors. The authors grant the Society for Neuroscience an exclusive license to publish their work for the first 6 months. After 6 months the work becomes available to the public to copy, distribute, or display under a Creative Commons Attribution 4.0 International (CC BY 4.0) license.Peer reviewedPublisher PD

A new poverty profile for Brazil using PPV, PNAD and census data

This paper contains a poverty profile for Brazil, based on 1996 data. Poverty measures and shares are presented for a wide range of population subgroups, based on household level data from the PNAD 1996, adjusted for imputed rents and spatial differences in cost of living. Robustness of the profile is verified with respect to different poverty lines, different spatial price deflators, and different equivalence scales. Overall poverty incidence ranges from 23% with respect to an indigence line (15% for urban areas) to 45% with respect to a more generous poverty line (37% for urban areas). More importantly however, poverty is found to vary significantly across regions and city sizes, with rural areas, small and medium towns and the metropolitan peripheries of the North and Northeast regions being poorest. In addition, education, race and the labor status of the household head are important correlates of vulnerability. The marginal impact of each of these attributes, controlling for all others, is investigated through probit regressions run on PPV data. These confirm the importance of spatial variables, but suggest that education remains the central personal attribute determining the likelihood that a household experiences poverty. Some tentative recommendations to improve the quality of the available data sets are also made.

Drug Targeting Mini-Symposium of the Division for Medicinal Chemistry (DMC) of the Swiss Chemical Society (SCS), at the Department of Chemistry, University of Basel, May 29, 2008: Conference Report

Specific targeting of drugs to their respective target organs or tissues is challenging. Substantial research efforts have been undertaken in the recent past to develop target specific drugs or drug conjugates. Such concepts are most relevant in rather severe diseases like cancer since it helps to reduce the concentration of frequently rather toxic drugs outside the tumor tissue. Various techniques can be used to specifically direct a drug or a drug conjugate to a specific tumor tissue such as using antibodies directed against tumor specific proteins, as nanoparticles or nano-sized polymer conjugates carrying tumor-specific recognition elements or by applying the active drug principle in a prodrug form designed to be liberated specifically in tumor tissue. Three speakers from the academia and one speaker from industry described different approaches and their respective potentials from various perspectives in the lectures entitled: 'Polymer Therapeutics and other Nanomedicines as Targetable Cancer Therapies', 'Design, Application, and Chemical Biology of Tumor-Targeting Drug Conjugates', 'Antibody-Based Vascular Tumor Targeting: From the Bench to the Clinic', and 'Discovery of Capecitabine, a Rationally Designed and Tumor-Activated Oral Prodrug of 5-FU, and Beyond'

Methods and apparatus for additive manufacturing of glass

In illustrative implementations of this invention, a crucible kiln heats glass such that the glass becomes or remains molten. A nozzle extrudes the molten glass while one or more actuators actuate movements of the nozzle, a build platform or both. A computer controls these movements such that the extruded molten glass is selectively deposited to form a 3D glass object. The selective deposition of molten glass occurs inside an annealing kiln. The annealing kiln anneals the glass after it is extruded. In some cases, the actuators actuate the crucible kiln and nozzle to move in horizontal x, y directions and actuate the build platform to move in a z-direction. In some cases, fluid flows through a cavity or tubes adjacent to the nozzle tip, in order to cool the nozzle tip and thereby reduce the amount of glass that sticks to the nozzle tip

Passenger's satisfaction toward service quality at Melaka International Airport (MIA) / Siti Nurfatin Mohammad Fadzilah , Nor Faezah Mohd Radzi and Margret Neri Peter

This chapter illustrates the general description of this study. It started with the background of the study which expressed the SERQUAL dimensions towards passenger satisfaction. Next, the identification of research issues was organized in the problem statement. From there, the research objectives, research questions and theoretical framework were developed and presented accordingly. Lastly, the researcher discussed about the significance of the study and its contribution towards management of Malacca International Airport, academician as well as the passengers