Speckle removal using a maximum-likelihood technique with isoline gray-level regularization

We propose a method based on the maximum-likelihood technique for removing speckle patterns that plague coherent images. The proposed method is designed for images whose gray levels vary continuously in space. The image model is based on a lattice of nodes corresponding to vertices of triangles in which the gray level of each pixel is produced by linear interpolation. A constraint on isoline gray levels is introduced to regularize the solution.     

Biomolecule-compatible support structures for biomolecule coupling to physical measuring principle surfaces

As part of studies on biomolecule-compatible interfacial structures for practice-relevant biosensor and biochip developments, new film-forming aminocelluloses of the 'P-CH2-NH-(X)-NH2' type (P = cellulose) with spacer structures (X = special oligoamine residues) at C6 and solubilising groups (S = tosylate or carbanilate) at C2C3 of the anhydroglucose unit (AGU) were synthesised and their film properties and covalent coupling with enzyme protein examined. Depending on the nature and degree of substitution (DS(S)) of the ester groups (S) at C2C3, the new aminocellulose derivatives are soluble either in DMA and DMSO (with S = carbanilate) or in water (with S = tosylate). The aminocellulose derivatives form transparent films from their solutions. AFM investigations of the film surfaces have either shown very flat (topography <1 nm) films or tubular topographies of nanostructure size, depending on structural and environment-induced factors of influence. Especially in the case of films from water-soluble aminocelluloses with oligoamine residues at C6, inter alia, enzyme-specific pH values and different positive charge distributions can be adjusted by partial protonation of the NH2 end groups. By means of the covalent coupling of the new aminocelluloses with glucose oxidase (GOD) it was shown that the enzyme coupling efficiency can be decisively optimised by the interplay of aminocellulose structure, coupling structure and enzyme protein.     

Development and evaluation of an affordable lift device to reduce musculo-skeletal injuries among home support workers

Home support workers (HSWs) work in clients' homes assisting with rehabilitation and activities of daily living. Like all health-care professionals, HSWs are at an increased risk for developing back injuries. Lift devices have been shown to reduce injuries to the worker. Presently, there are few lifting devices for home use that cost under $4000 CDN. Our study involved designing a safe and affordable lift device (retail cost under $2000 CDN) to be used by HSWs in the home and evaluating it in a typical bathroom. Thirty-eight HSWs and three seniors evaluated the BCIT lift, a commercially available lift (BHM Medical Inc.) and the manual method of transfer and lift. Results indicated that the BCIT lift was an improvement over the manual method of transferring, and approximated the more expensive, automatic lift in terms of perceived exertion, ease of use and safety. Feedback provided to the researchers has been incorporated into a new, ergonomically sound and marketable lift device.     

Consumers' use of written product information

Two studies were conducted to investigate the predictive role of person-specific, product-specific, and situation-specific influences on the use of instruction manuals in the field of electrical consumer products. In a laboratory study, 42 participants were observed while putting a vacuum cleaner into operation. Situational primes (i.e., receiving a verbal cue that the packaging contains an instruction manual) increased the probability of the user manual being read. Additional verbal information that the manual contains information on energy-saving behaviours was especially motivating for persons with high environmental concern. Self-report data, collected on a wide range of products, suggest that product complexity is the best predictor of instruction manual use. In a second study with 30 participants, different positions of product labels were compared, i.e. placing the information on the packaging or directly onto the product. Information placed directly onto the product had a significantly higher influence on participants' actual behaviour than providing the same information on the packaging.     

Cardiovascular and thermal consequences of protective clothing: a comparison of clothed and unclothed states

We have undertaken a laboratory-based examination of the cardiovascular and thermal impact of wearing thermal (heat) protective clothing during fatiguing exercise in the heat. Seven males completed semi-recumbent, intermittent cycling (39.6 degrees C, 45% relative humidity) wearing either protective clothing or shorts (control). Mean core and skin temperatures, cardiac frequency (f(c)), stroke volume (Q), cardiac output (Q), arterial pressure, forearm blood flow (Q(f)), plasma volume change, and sweat rates were measured. In the clothed trials, subjects experienced significantly shorter times to fatigue (52.5 vs. 58.9 min), at lower peak work rates (204.3 vs. 277.4 W), and with higher core (37.9 degrees vs. 37.5 degrees C) and mean skin temperatures (37.3 degrees vs. 36.9 degrees C). There was a significant interaction between time and clothing on f(c), such that, over time, the clothing effect became more powerful. Clothing had a significant main affect on Q, but not Q, indicating the higher Q was chronotropically driven. Despite a greater sweat loss when clothed (923.0 vs. 547.1 g.m(-2) x h(-1); P<0.05), Q(f) and plasma volume change remained equivalent. Protective clothing reduced exercise tolerance, but did not affect overall cardiovascular function, at the point of volitional fatigue. It was concluded that, during moderately heavy, semi-recumbent exercise under hot, dry conditions, the strain on the unclothed body was already high, such that the additional stress imparted by the clothing ensemble represented a negligible, further impact upon cardiovascular stability.     

Physical models for moving shadow and object detection in video

Current moving object detection systems typically detect shadows cast by the moving object as part of the moving object. In this paper, the problem of separating moving cast shadows from the moving objects in an outdoor environment is addressed. Unlike previous work, we present an approach that does not rely on any geometrical assumptions such as camera location and ground surface/object geometry. The approach is based on a new spatio-temporal albedo test and dichromatic reflection model and accounts for both the sun and the sky illuminations. Results are presented for several video sequences representing a variety of ground materials when the shadows are cast on different surface types. These results show that our approach is robust to widely different background and foreground materials, and illuminations.     

A graphical tool for parasite genome annotation

A graphical tool to facilitate rapid primary annotation of genomic sequence has been developed. Within a single interface the user can import sequences or database entries, run feature prediction programs and similarity searches, filter results, add additional manually found features and notes, and finally export annotations for database submission. Integrated rule-based feature corroboration and a novel decision support heuristic using ORF orientation, length and base-composition further enhances the efficiency of the annotation process without compromising flexibility. The program has been explicitly tailored to use in protozoan parasite genome projects, but can constitute a useful tool for prokaryote annotation as well. It is successfully being used by our lab in the Trypanosoma cruzi genome project, and can be obtained from the authors upon request.     

Texture-based approaches for identifying neuro-anatomical structures and electrode tracks

An automated approach to identifying electrode tracks and neuro-anatomical structures (nuclei) was developed using texture attributes of their neuro-anatomical stains. The properties that make up the texture features of the nuclei include size, shape and distribution of elemental structures. The electrode tracks are characterized by elongated darkened formations due to gliosis. Based on a Gabor wavelet transform, a texture feature vector was constructed, consisting of localized texture energies along different orientations at different scales. Stained images of brainstem sections in the vestibular nuclei were segmented using partitional clustering in feature space. A metric that computes the location of the tracks relative to the nuclei centers was then implemented. This methodology should be useful for quantifying and automating the procedure by which tracks are localized in anatomical structures.     

Fair attribution of functional contribution in artificial and biological networks

This letter presents the multi-perturbation Shapley value analysis (MSA), an axiomatic, scalable, and rigorous method for deducing causal function localization from multiple perturbations data. The MSA, based on fundamental concepts from game theory, accurately quantifies the contributions of network elements and their interactions, overcoming several shortcomings of previous function localization approaches. Its successful operation is demonstrated in both the analysis of a neurophysiological model and of reversible deactivation data. The MSA has a wide range of potential applications, including the analysis of reversible deactivation experiments, neuronal laser ablations, and transcranial magnetic stimulation "virtual lesions," as well as in providing insight into the inner workings of computational models of neurophysiological systems.