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Health Canada’s Wind Turbine Noise and Health Study—A Review Exploring Research Challenges, Methods, Limitations and Uncertainties of Some of the Findings  [PDF]
Carmen M. Krogh, Anne Dumbrille, Robert Y. McMurtry, Richard James, Robert W. Rand, Michael A. Nissenbaum, Jeffery J. Aramini, Stephen E. Ambrose
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1105046
Abstract: Background: Risk of harm associated with wind turbines is debated globally. Some people living or working in proximity to wind turbines report adverse health effects such as sleep disturbance, noise annoyance, and diminished quality of life. Due to public concern, Health Canada announced its wind turbine noise and health study which included subjective and objective measurements. Findings were published between 2014 and 2016. In 2018, Health Canada published clarifications regarding the design and interpretation of study conclusions. Methods: Methods and subjective/objective findings were reviewed. Peer reviewed publications, conference presentations, judicial proceedings, government documents, and other sources were evaluated and considered in context with advanced methods for investigating reports of adverse health effects. Objectives: To review and explore some of the research challenges, methods, strengths and limitations of findings and conclusions. To participate in scientific dialogue and contribute towards an understanding of reported health risks associated with wind turbine noise. Results: Wind turbine human health research is challenged by numerous variables. Knowledge gaps and individual human and wind turbine variables are identified. Strengths and advisories of limitations are considered and acknowledged. Health Canada’s advisories that its study design does not permit any conclusions about causality and results may not be generalized beyond the sample taken in Canada are supported. Enhanced methods for investigating health outcomes are proposed including establishing referral resources within medical facilities for physicians. It is proposed staffing of the resource center include multidisciplinary teams of physicians, epidemiologists, acousticians and other specialists to investigate suspected wind turbine adverse health effects. Discussion: A review and appraisal of some of the research challenges associated with wind turbine human health research are presented. Given the identified methods, research/knowledge gaps, and limitations and cautionary advisories, Health Canada’s results should be carefully considered when predicting or protecting from health risks of wind turbine noise.
Place Cells, Grid Cells, Attractors, and Remapping
Kathryn J. Jeffery
Neural Plasticity , 2011, DOI: 10.1155/2011/182602
Abstract: Place and grid cells are thought to use a mixture of external sensory information and internal attractor dynamics to organize their activity. Attractor dynamics may explain both why neurons react coherently following sufficiently large changes to the environment (discrete attractors) and how firing patterns move smoothly from one representation to the next as an animal moves through space (continuous attractors). However, some features of place cell behavior, such as the sometimes independent responsiveness of place cells to environmental change (called “remapping”), seem hard to reconcile with attractor dynamics. This paper suggests that the explanation may be found in an anatomical separation of the two attractor systems coupled with a dynamic contextual modulation of the connection matrix between the two systems, with new learning being back-propagated into the matrix. Such a scheme could explain how place cells sometimes behave coherently and sometimes independently. 1. Introduction The hippocampal place cells are thought to collectively form a representation of space, known as a “cognitive map” [1], because of their spatially localized firing, which occurs in patches known as place fields (Figure 1(a)). One source of spatial inputs to place cells is the entorhinal grid cells, one synapse upstream, whose activity forms a regular array of firing fields [2] suggestive of an intrinsic odometric (distance-measuring) process, which may convey metric information to place cells and allow them to position their place fields accurately in space [3]. The place and grid cells are an excellent model system with which to study the formation and architecture of cognitive knowledge structures. Figure 1: (a) Activity of a CA1 place cell, recorded as a rat foraged for rice grains in a 60?cm-square box for four min. The top plot shows the raw spikes (black squares) superimposed on the path of the rat as it (grey line), and the bottom plot shows a contour plot of firing rate, shown in 20% gradations (black = the peak 20% region). (b) Examples of remapping from two cells in CA1, as a box was changed from black to white. Cell 1 remapped by changing the location of its firing field, while Cell 2 remapped by switching its field off. (c) Evidence for discrete attractors in CA1, adapted from [ 9]. As an environment was incrementally “morphed” between more circle-like and more square-like (visible as the slightly lengthening corners as the diagrams go from left to right), the cells abruptly and coherently (all together) changed their activity. (d) Cross-sectional attractor
Danish Team wins First BIOMOD International Undergraduate Nanobiology Design Competition
Constance J. Jeffery
Nano Reviews , 2012, DOI: 10.3402/nano.v3i0.17201
Abstract:
Engineering periplasmic ligand binding proteins as glucose nanosensors
Constance J. Jeffery
Nano Reviews , 2011, DOI: 10.3402/nano.v2i0.5743
Abstract: Diabetes affects over 100 million people worldwide. Better methods for monitoring blood glucose levels are needed for improving disease management. Several labs have previously made glucose nanosensors by modifying members of the periplasmic ligand binding protein superfamily. This minireview summarizes recent developments in constructing new versions of these proteins that are responsive within the physiological range of blood glucose levels, employ new reporter groups, and/or are more robust. These experiments are important steps in the development of novel proteins that have the characteristics needed for an implantable glucose nanosensor for diabetes management: specificity for glucose, rapid response, sensitivity within the physiological range of glucose concentrations, reproducibility, and robustness.
The computation of stationary distributions of Markov chains through perturbations
Jeffery J. Hunter
International Journal of Stochastic Analysis , 1991, DOI: 10.1155/s1048953391000023
Abstract: An algorithmic procedure for the determination of the stationary distribution of a finite, m-state, irreducible Markov chain, that does not require the use of methods for solving systems of linear equations, is presented. The technique is based upon a succession of m, rank one, perturbations of the trivial doubly stochastic matrix whose known steady state vector is updated at each stage to yield the required stationary probability vector.
Radioactive Decay Energy Deposition in Supernovae and the Exponential/Quasi-Exponential Behavior of Late-Time Supernova Light Curves
David J. Jeffery
Physics , 1999,
Abstract: The radioactive decay energy (RDE) deposition in supernovae from the decay chain Ni56-Co56-Fe56 usually directly powers the UV/optical/IR (UVOIR) bolometric luminosity of supernovae in their quasi-steady state phase until very late times. The result for this phase is exponential/quasi-exponential UVOIR bolometric light curves and often exponential/quasi-exponential broad band light curves. A presentation is given of a simple, approximate, analytic treatment of RDE deposition that provides a straightforward understanding of the exponential/quasi-exponential behavior of the UVOIR bolometric luminosity and a partial understanding of the exponential/quasi-exponential behavior of the broad band light curves. The treatment reduces to using a normalized deposition function N_{Ni}^{*}(t) as an analysis tool. The one free parameter of N_{Ni}^{*}(t) is a fiducial time t_{0} which governs time-varying gamma-ray optical depth behavior of a supernova. The N_{Ni}^{*}(t) function is used to analyze the preliminary UVOIR bolometric light curve of SN Ic 1998bw (the possible cause of gamma-ray burst GRB980425). The SN 1998bw t_{0} is found to be 134.42 days and a prediction is made for the evolution of the SN 1998bw RDE deposition curve and quasi-steady state UVOIR bolometric light curve out to day 1000 after the explosion. A very crude estimate of the SN 1998bw mass obtained from the light curve analysis is 4.26 M_{Sun}. As further examples of the simple analytic treatment, the RDE deposition and luminosity evolution of SN Ia 1992A and SN II 1987A have also been examined. The simple analytic treatment of RDE deposition has actually existed for 20 years at least without, apparently, being discussed at length. The main value of this paper is the explicit, detailed, general presentation of this analytic treatment.
A Grey Radiative Transfer Procedure For Gamma-ray Transfer in Supernovae
David J. Jeffery
Physics , 1998,
Abstract: The gamma-ray transfer in supernovae for the purposes of energy deposition in the ejecta can be approximated fairly accurately as frequency-integrated (grey) radiative transfer using a mean opacity as shown by Swartz, Sutherland, & Harkness (SSH). In SSH's grey radiative transfer procedure (unoptimized) the mean opacity is a pure absorption opacity and it is a constant aside from a usually weak composition dependence. In this paper, we present a variation on the SSH procedure which uses multiple mean opacities which have both absorption and scattering components. There is a mean opacity for each order of Compton scattering. A local-state (LS) approximation permits an analytic solution for the gamma-ray transfer of scattered gamma-ray fields. The LS approximation is admittedly crude, but the scattered fields are always of lesser importance to the energy deposition. We call our procedure the LS grey radiative transfer procedure or LS procedure for short. For a standard Type Ia supernova (SN Ia) model the uncertainty in gamma-ray energy deposition is estimated to be of order 10 % or less. The LS procedure code used for this paper can be obtained by request from the author. For completeness and easy reference, we include in this paper a review of the gamma-ray opacities important in supernovae, a discussion of the appropriate mean opacity prescription, and a discussion of the errors arising from neglecting time-dependent and non-static radiative transfer effects.
A grey gamma-ray transfer procedure for supernovae
David J Jeffery
Physics , 1998,
Abstract: The gamma-ray transfer in supernovae for the purposes of energy deposition in the ejecta can be approximated as grey radiative transfer using mean opacities. In past work there is a single pure absorption mean opacity which is a free parameter. Accurate results can be obtained by varying this mean opacity to fit the results of more accurate procedures. In this paper, we present a grey gamma-ray transfer procedure for energy deposition in which there are multiple mean opacities that are not free parameters and that have both absorption and scattering components. This procedure is based on a local-state (LS) approximation, and so we call it the LS grey gamma-ray transfer procedure or LS procedure for short.
Right Hemisphere Cerebral Infarction Due to Air Embolism from Percutaneous Lung Biopsy: A Case Report  [PDF]
Chaitanya Ahuja, Yama Kharoti, Jeffery J. Critchfield, Meghna Chadha
Open Journal of Radiology (OJRad) , 2013, DOI: 10.4236/ojrad.2013.33021
Abstract:

Percutaneous transthoracic needle biopsy is a common procedure in interventional radiology. Systemic arterial air embolism causing cerebral infarction is a rare but much feared complication of percutaneous lung biopsy. We present a comprehensive review of iatrogenic air embolism post-lung biopsy, a complication that is often sub optimally managed. Patho-physiology, clinical features, and risk factors and management are reviewed.

Recombinant Expression Screening of P. aeruginosa Bacterial Inner Membrane Proteins
Vidya Madhavan, Forum Bhatt, Constance J Jeffery
BMC Biotechnology , 2010, DOI: 10.1186/1472-6750-10-83
Abstract: Plasmid clones were obtained that encode eighty-seven transmembrane proteins with varying physical characteristics, for example, the number of predicted transmembrane helices, molecular weight, and grand average hydrophobicity (GRAVY). All the target proteins were from P. aeruginosa, a gram negative bacterial opportunistic pathogen that causes serious lung infections in people with cystic fibrosis. The relative expression levels of the transmembrane proteins were measured under several culture growth conditions. The use of E. coli strains, a T7 promoter, and a 6-histidine C-terminal affinity tag resulted in the expression of 61 out of 87 test proteins (70%). In this study, proteins with a higher grand average hydrophobicity and more transmembrane helices were expressed less well than less hydrophobic proteins with fewer transmembrane helices.In this study, factors related to overall hydrophobicity and the number of predicted transmembrane helices correlated with the relative expression levels of the target proteins. Identifying physical characteristics that correlate with protein expression might aid in selecting the "low hanging fruit", or proteins that can be expressed to sufficient levels using an E. coli expression system. The use of other expression strategies or host species might be needed for sufficient levels of expression of transmembrane proteins with other physical characteristics. Surveys like this one could aid in overcoming the technical bottlenecks in working with TM proteins and could potentially aid in increasing the rate of structure determination.Ion transport, cell-cell communication, vesicle transport, maintenance of cellular structure, drug resistance, host-pathogen interactions and many other vital cellular activities involve proteins that are embedded in the cell membrane. Transmembrane [TM] proteins make up over 25% of an organism's proteins [1-3] and are the targets for the majority of pharmaceuticals in use today [4]. The improper folding
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