A neural network based spatial light scattering instrument for hazardous airborne fiber detection

This paper was published in Applied Optics and is made available as an electronic reprint with the permission of OSA. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited. Copyright OSA (www.osa.org/pubs/osajournals.org)A laser light scattering instrument has been designed to facilitate the real-time detection of potentially hazardous respirable fibers, such as asbestos, within an ambient environment. The instrument captures data relating to the spatial distribution of light scattered by individual particles in flow using a dedicated multi-element photodiode detector array. These data are subsequently processed using an artificial neural network which has previously been trained to recognise those features or patterns within the light scattering distribution which may be characteristic of the specific particle types being sought, such as for example, crocidolite or chrysotile asbestos fibers. Each particle is thus classified into one of a limited set of classes based upon its light scattering properties, and from the accumulated data a particle concentration figure for each class may be produced and updated at regular intervals. Particle analysis rates in excess of 103 per second within a sample volume flow-rate of 1 litre per minute are achievable, offering the possibility of detecting fiber concentrations at the recommended maximum exposure limit of 0.1 fibers/ml within a sampling period of a few seconds.Peer reviewe

Hierarchical Agglomerative Cluster Analysis Applied to WIBS 5-Dimensional Bioaerosol Data Sets

Peer reviewe

Regular Grids: An Irregular Approach to the 3D Modelling Pipeline

The 3D modelling pipeline covers the process by which a physical object is scanned to create a set of points that lay on its surface. These data are then cleaned to remove outliers or noise, and the points are reconstructed into a digital representation of the original object. The aim of this thesis is to present novel grid-based methods and provide several case studies of areas in the 3D modelling pipeline in which they may be effectively put to use. The first is a demonstration of how using a grid can allow a significant reduction in memory required to perform the reconstruction. The second is the detection of surface features (ridges, peaks, troughs, etc.) during the surface reconstruction process. The third contribution is the alignment of two meshes with zero prior knowledge. This is particularly suited to aligning two related, but not identical, models. The final contribution is the comparison of two similar meshes with support for both qualitative and quantitative outputs

Leishmaniasis: new approaches to disease control.

The leishmaniases afflict the world's poorest populations. Among the two million new cases each year in the 88 countries where the disease is endemic (fig 1), it is estimated that 80% earn less than $2 a day. Human infections with Leishmania protozoan parasites, transmitted via the bite of a sandfly, cause visceral, cutaneous, or mucocutaneous leishmaniasis. The global burden of leishmaniasis has remained stable for some years, causing 2.4 million disability adjusted life years (DALYs) lost and 59 000 deaths in 2001. Neglected by researchers and funding agencies, leishmaniasis control strategies have varied little for decades, but in recent years there have been exciting advances in diagnosis, treatment, and prevention. These include an immunochromatographic dipstick for diagnosing visceral leishmaniasis; the licensing of miltefosine, the first oral drug for visceral leishmaniasis; and evidence that the incidence of zoonotic visceral leishmaniasis in children can be reduced by providing dogs with deltamethrin collars. There is also hope that the first leishmaniasis vaccine will become available within a decade. Here we review these developments and identify priorities for research

Scattering of non-uniform incident fields by long cylinders

Copyright University of BremenWe investigate experimentally far-field scattering from cylinders with illumination non-uniform along the axis of the cylinder. Scattered intensity as a function of angle in two orthogonal directions is examined. Variation along the scattering angle is found to be little affected by the illumination profile. However, variation in the transverse direction follows closely the Fourier transform of the illumination pattern and reproduces the angular distribution of the incident wave. These finding apply to circular as well as hexagonal cross-section cylinders

evaluation of a theory based childhood overweight prevention curriculum

Food Fit, a social cognitive theory based (SCT) nutrition intervention, was implemented to 3rd-5th grade student’s at 5 YMCA after-school programs to impact specific dietary behaviors associated with the prevention of childhood overweight (n = 58). Pre and post tests were administered for each lesson to evaluate changes in behavioral capabilities (BC), self efficacy (SE), and outcome expectancies (OE) for each lesson's key objectives. A child-modified Food Behavior Checklist was administered before and after the program to evaluate dietary behaviors. Results showed significant improvements for SCT psychosocial variables (i.e. outcome expectancies for eating raw vegetables (p<0.01), self efficacy for eating fruit (p<.05)) Significant dietary changes included an increased consumption of fruits and vegetables as snacks (p<.001), citrus fruits and juice (p<0.02), raw vegetables (p<.001), and increased use of the food label to determine food selection (p<0.001). The FF program appears to be successful at favorably impacting children's BC, SE and OE for food selection behaviors thought to contribute to the prevention and treatment of overweight and obesity. FF may be a viable nutrition program for use in multi-component interventions, aimed at impacting behaviors associated with the prevention and treatment of overweight and obesity

Process Evaluations for a Multisite Nutrition Education Program

Process evaluations are an often-overlooked component of evaluating health promotion interventions, but can be essential for interpreting program outcomes. The purpose of this study was to report the results of two types of process evaluations conducted for Food Fit, a nutrition education program implemented to 58 3rd through 5th grade children (67% Caucasian) in 5 YMCA after school programs. To evaluate program fidelity, a trained observer watched each lesson and recorded program adherence using a standardized checklist, outlining essential components of the intervention. Attendance was recorded by asking each child to complete a small task before and after each lesson. Results showed that program adherence was perfect in most cases and attendance rates varied, but were generally high. Attendance rates were not associated with improvement in nutrition behaviors. Implications and recommendations for future use of process evaluations are discussed

Critical Thinking in Teacher Education: A Process-Oriented Research Agenda

In recent years, critical thinking has become a central focus of education, especially in North America. Within this focus, there has been a major debate regarding the generalisability of specificity of critical thinking. The main issue in this connection appears to have been whether critical thinking needs to be closely linked with traditional disciplines. If critical thinking is really as vital as its proponents maintain, then it will also be important in applied fields such as teacher education. It is our intention in this paper to explore the implications, for teacher education, of taking critical thinking seriously