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Continual Improvement in Laboratory Quality Management System of a Regulatory Laboratory in West Africa
Get PDFMedicines quality monitoring and quality control are essential components required to deliver health value to the people. These will also improve access to quality assured medical products that are safe for intended use. Quality Control Laboratories play an essential role in strengthening health systems in West Africa. Their role in providing excellent testing services that ensures correctness, trust, and consistency of laboratory test results is key in assuring product quality. Improving the laboratory Quality Management System (QMS) will require concerted and coordinated efforts by all interested parties in establishing relevant, continual improvement plans/strategies that will sustain and improve all components of the laboratory QMS
Book Review of Drawn Together by Minh Lê and Dan Santat
No full textDrawn Together, written by Minh Lê and illustrated by Dan Santat, depicts the story of a grandson and grandfather spending time in the afternoon together. Lê and Santat’s shared experiences and cultures influence the picturebook’s construction. The greatest strength in Drawn Together is the inclusion of family in the creation process. Lê’s meaningful words and phrases complement Santat’s colorful and energetic illustrations. The setting is in the grandfather’s house and away from the site of Thai restaurants and Thai Buddhist temples, to which most of the existing research on Thai Americans hones it on (Bao, 2015; Padoongpatt, 2017). Drawn Together is a humanizing experience for readers to witness the developing relationship between the grandfather and grandson. The two have nothing in common, speak different languages, and find a connection through drawing. This book review discusses the cultural and lingual ties that make reading Drawn Together worthy of critique
Characterization of perceptual spaces from triadic similarity judgments
Get PDFPerceptual spaces are mental workspaces that organize a sensory or cognitive domain into a format that supports functions such as comparison, grouping, learning, and generalization. Determining the geometry of a perceptual space – i.e., the properties of the perceptual distances within the space -- is thus crucial not only to understand these intermediate levels of processing at an algorithmic level, but also as a starting point for comparison with neural measures of similarity. While perceptual spaces are often taken to be Euclidean or nearly so (the classic example is trichromatic color space), this assumption, when tested, is often violated. Moreover, entirely different geometries, such as distances on trees, may be more appropriate models for perceptual spaces with semantic content.
Here, rather than starting with a Euclidean model and asking whether adjustments need to be made, I take a complementary approach of identifying inferences that can be made directly from triadic judgments (is X or Y more similar to Z?). Each such judgment yields a ranking of distances but not a numerical relationship between them. Nevertheless, the set of rankings constrains models of the perceptual space. In particular, it yields indices of three geometrical characteristics: (i) consistency with symmetry; (ii) consistency with an “ultrametric” model (i.e., a strict hierarchy); and (iii) consistency with an “addtree” model (a graph-distance model, proposed by Tversky et al.). I provide examples from texture- and face-comparison experiments and outline some directions for further progress
A Foveated Model Of Visual Discrimination Based On Windowed Texture Statistics
Get PDFMost information from visual scenes is discarded by the human nervous system and thus cannot influence visual behavior. Here, we investigated the loss of spatial pattern information. This loss increases dramatically with eccentricity. Recently, models have been developed that average image features in pooling windows whose diameters scale with eccentricity. These models can be used to synthesize “metamers” of natural scenes, images which are physically different but perceptually indistinguishable. Psychophysical experiments have identified the maximum window scaling for which model discrimination abilities match human performance (“critical scaling”). If images are synthesized with pooling windows that exceed critical scaling (“supercritical scaling”), the models make no prediction about performance. The models therefore do not account for the observation that, at supercritical scaling, performance is far better when discriminating between a synthesized image and a natural image, rather than between two synthesized images. We hypothesized that this performance difference arises from differential information loss in downstream processing. To test this, we implemented an observer model that pools image features (high-order texture statistics), followed by divisive normalization and additive noise. We then compared model performance to human performance on images synthesized with pooling models of earlier stage image features (local luminance or local spectral energy) at supercritical scaling. The observer model qualitatively accounted for the primary psychophysical effects, including a performance advantage for discriminating synthesized from natural images. Accurately predicting discriminability of stimuli whose early visual representations do not match requires accounting for information loss in later stages of processin
Feature Integration and Spatial Localization for Attention across the Visual Hierarchy
Get PDFThe featural and spatial specificity of visual representations broadly decrease along the ventral visual stream. The selection of behaviorally relevant information, or attention, must therefore establish spatial correspondence across the visual hierarchy while maintaining behavioral guidance to relevant visual features. Moreover, selection is often accompanied by an inhibitory surround as well as selective inhibition of distractor items. Considering these key functions, we describe a biologically realistic computational theory of visual selection and inhibition through feedforward and feedback signals along the ventral visual stream, complemented by feature-agnostic spatial competition in the pulvinar nuclei. Our model simulates signature visual search behaviors and the N2pc and Pd, which are EEG correlates of attention
Librarians as faculty developers: Shaping disciplinary classroom experiences through information literacy
Get PDFInvolvement in faculty development is a promising approach to realizing academic libraries’ goals for information literacy. This study examines an inter-institutional program where librarians partnered with classroom instructors to create projects where students learned to use information in disciplinary ways. Using thematic analysis to examine participant materials, the findings suggest that the informed learning design model underpinning the program supported the creation of information-rich projects and fostered a sense of empowerment in librarians serving as faculty developers. Librarians can advance their role as educators by partnering with classroom instructors and presenting information literacy as a way to foster disciplinary learning
U.S. Government Agency Podcasts
No full textPresents podcasts from U.S. Government agencies which can be discovered through the U.S. Government Publishing Office\u27s Catalog of Government Publications. Agencies whose podcasts are presented include the National Institutes of Health, U.S. Peace Corps, U.S. Department of Agriculture, Government Accountability Office (GAO), National Park Service, Department of Justice, Federal Reserve System, and U.S. Naval War College
