Supporting the manufacturing sector in the Toronto commuter area (TCA)

Local levels of government can play a vital role in supporting the competitiveness of their regional economy by targeting the needs of manufacturers. This paper explored the question: What services, incentives and programs could Canada’s largest economic region, the Toronto Commuter Area (TCA), deliver to support a competitive manufacturing economy? Using a survey to assess the local issues facing manufacturing, this research advances the current thinking of the role local and regional economic developers play in ensuring a competitive marketplace for this key base industry. In general, manufacturers prefer less government intervention.   Keywords: manufacturing, Toronto Commuter Area (TCA), local economic developmen

Magic angle spinning (MAS) NMR linewidths in the presence of solid-state dynamics

In solid-state NMR, the magic angle spinning (MAS) technique fails to suppress anisotropic spin interactions fully if reorientational dynamics are present, resulting in a decay of the rotational-echo train in the time-domain signal. We show that a simple analytical model can be used to quantify this linebroadening effect as a function of the MAS frequency, reorientational rate constant, and magnitude of the inhomogeneous anisotropic broadening. We compare this model with other theoretical approaches and with exact computer simulations, and show how it may be used to estimate rate constants from experimental NMR data

A concurrent engineering approach to develop BioMEMS employed in a deep brain stimulator integrated with a drug delivery system

This paper presents an Integrated Product Development (IPD) based model to specifically develop bio-medical micro-electro-mechanical-systems (BioMEMS). The concurrent engineering model is based on the IPD model phases, which are presented and formulated by the Integration DEFinition (IDEF) model- ling language. To evaluate the IPD model, a case study concerning the development of a BioMEMS device for a deep brain stimulation (DBS) system was investigated. By following the relevant mechanisms and controls in the model, a design concept of a wireless head-mounted DBS implant integrated with a drug delivery system (DDS) was conceived. The contribution of this paper is the IDEF model, which provides a road map to the product development team members in order to take a concurrent engineering approach to develop Bio-MEMS. The qualitative feedback received from the identified stakeholders, together with the quality of the case study employed, namely, an integrated DBS and DDS solution, indicate a degree of evidence that the model provides a sound basis in this direction.peer-reviewe

BrachyView, a novel in-body imaging system for HDR prostate brachytherapy: Experimental evaluation

© 2015 American Association of Physicists in Medicine. Purpose: This paper presents initial experimental results from a prototype of high dose rate (HDR) BrachyView, a novel in-body source tracking system for HDR brachytherapy based on a multipinhole tungsten collimator and a high resolution pixellated silicon detector array. The probe and its associated position estimation algorithms are validated and a comprehensive evaluation of the accuracy of its position estimation capabilities is presented. Methods: The HDR brachytherapy source is moved through a sequence of positions in a prostate phantom, for various displacements in x, y, and z. For each position, multiple image acquisitions are performed, and source positions are reconstructed. Error estimates in each dimension are calculated at each source position and combined to calculate overall positioning errors. Gafchromic film is used to validate the accuracy of source placement within the phantom. Results: More than 90% of evaluated source positions were estimated with an error of less than one millimeter, with the worst-case error being 1.3 mm. Experimental results were in close agreement with previously published Monte Carlo simulation results. Conclusions: The prototype of HDR BrachyView demonstrates a satisfactory level of accuracy in its source position estimation, and additional improvements are achievable with further refinement of HDR BrachyView's image processing algorithms

BrachyView, A novel inbody imaging system for HDR prostate brachytherapy: Design and Monte Carlo feasibility study

Purpose: High dose rate (HDR) brachytherapy is a form of radiation therapy for treating prostate cancer whereby a high activity radiation source is moved between predefined positions inside applicators inserted within the treatment volume. Accurate positioning of the source is essential in delivering the desired dose to the target area while avoiding radiation injury to the surrounding tissue. In this paper, HDR BrachyView, a novel inbody dosimetric imaging system for real time monitoring and verification of the radioactive seed position in HDR prostate brachytherapy treatment is introduced. The current prototype consists of a 15 × 60 mm2 silicon pixel detector with a multipinhole tungsten collimator placed 6.5 mm above the detector. Seven identical pinholes allow full imaging coverage of the entire treatment volume. The combined pinhole and pixel sensor arrangement is geometrically designed to be able to resolve the three-dimensional location of the source. The probe may be rotated to keep the whole prostate within the transverse plane. The purpose of this paper is to demonstrate the efficacy of the design through computer simulation, and to estimate the accuracy in resolving the source position (in detector plane and in 3D space) as part of the feasibility study for the BrachyView project. Methods: Monte Carlo simulations were performed using the GEANT4 radiation transport model, with a 192Ir source placed in different locations within a prostate phantom. A geometrically accurate model of the detector and collimator were constructed. Simulations were conducted with a single pinhole to evaluate the pinhole design and the signal to background ratio obtained. Second, a pair of adjacent pinholes were simulated to evaluate the error in calculated source location. Results: Simulation results show that accurate determination of the true source position is easily obtainable within the typical one second source dwell time. The maximum error in the estimated projection position was found to be 0.95 mm in the imaging (detector) plane, resulting in a maximum source positioning estimation error of 1.48 mm. Conclusions: HDR BrachyView is a feasible design for real-time source tracking in HDR prostate brachytherapy. It is capable of resolving the source position within a subsecond dwell time. In combination with anatomical information obtained from transrectal ultrasound imaging, HDR BrachyView adds a significant quality assurance capability to HDR brachytherapy treatment systems. © 2013 American Association of Physicists in Medicine

Radiation dose enhancement at tissue-tungsten interfaces in HDR brachytherapy

© 2014 Institute of Physics and Engineering in Medicine. HDR BrachyView is a novel in-body dosimetric imaging system for real-time monitoring and verification of the source position in high dose rate (HDR) prostate brachytherapy treatment. It is based on a high-resolution pixelated detector array with a semi-cylindrical multi-pinhole tungsten collimator and is designed to fit inside a compact rectal probe, and is able to resolve the 3D position of the source with a maximum error of 1.5 mm. This paper presents an evaluation of the additional dose that will be delivered to the patient as a result of backscatter radiation from the collimator. Monte Carlo simulations of planar and cylindrical collimators embedded in a tissue-equivalent phantom were performed using Geant4, with an 192Ir source placed at two different source-collimator distances. The planar configuration was replicated experimentally to validate the simulations, with a MOSkin dosimetry probe used to measure dose at three distances from the collimator. For the cylindrical collimator simulation, backscatter dose enhancement was calculated as a function of axial and azimuthal displacement, and dose distribution maps were generated at three distances from the collimator surface. Although significant backscatter dose enhancement was observed for both geometries immediately adjacent to the collimator, simulations and experiments indicate that backscatter dose is negligible at distances beyond 1 mm from the collimator. Since HDR BrachyView is enclosed within a 1 mm thick tissue-equivalent plastic shell, all backscatter radiation resulting from its use will therefore be absorbed before reaching the rectal wall or other tissues. dosimetry, brachytherapy, HD

Distribution, abundance and colony size of the invasive coral Oculina patagonica de Angelis, 1908 (Cnidaria, Scleractinia) in Malta

The zooxanthellate, scleractinian coral Oculina patagonica is known from various locations in both west and east basins of the Mediterranean Sea, but there are only three casual records of this cryptogenic species from the Central-Ionian area, all from Malta in 2017. Surveys at 28 sites around the Maltese coasts undertaken during the present work revealed 43 colonies spread across ten sites. The coral occurred primarily on artificial substrata in harbour areas at depths shallower than 6 m, but a few colonies occurred on natural rocky bottoms and in non-harbour sites. The largest colonies reached a mean diameter of up to 95 cm and occurred on artificial structures that are only a few decades old, while the majority of the colonies were much smaller (< 40 cm diameter). This, together with the clustering of records in harbour areas, suggests that O. patagonica was likely introduced in Maltese waters in recent decades via maritime transport. The present results also confirm that this species is established in the Central Mediterranean area.peer-reviewe

The participation of the small shareholder in the annual general meeting : a reflection of good corporate governance?

This paper analyses the level of small shareholder (SS) participation in the Annual General Meeting (AGM), assessing how this reflects upon the corporate governance of listed entities. It focuses on SS attendance, voting and proposals (excluding those of institutional and majority shareholders), improving SS participation and the significance of such AGM proceedings to listed company corporate governance. Empirical mixed methodology research is carried out in a Maltese listed company (LC) setting by means of semi-structured interviews with seventeen LC secretaries, five stockbrokers, an online questionnaire responded by fifty-four shareholders in different LCs, as well as the analysis of company notices and documentation relating to the AGM. Results indicate that SS participation is weak. Attendance is poor, and is often spurred both by legitimate factors such as information on current financial performance and by questionable ones such as refreshments served and venue. Shareholders seem uncomfortable in asking management formal questions and even in voting by show of hands, and therefore opt for informal interaction with management and for voting by poll, the latter often rendering attendance fruitless and even unnecessary by permitting proxies. As for proposals, they could induce management’s later action despite seldom, if ever, being approved, but their submission is rare and mostly frivolous, commonly hampered by a lack of financial knowledge. The study concludes that the current level of SS participation does not render the AGM a tool reflecting good corporate governance, as it does not keep in balance the interests of this shareholder with those of other stakeholders. For the sake of better direction and control, and, in particular, for more transparency and accountability, the AGM has to be less stage-managed, as well as more interactive and engaging towards such shareholder. This calls for increased management commitment, particularly towards more investor education and guidance.peer-reviewe

Apparent absence of the amphibian chytrid fungus (Batrachochytrium dendrobatidis) in frogs in Malaita Province, Solomon Islands

A major driver of global biodiversity loss is disease. One of the most devastating wildlife diseases known is chytridiomycosis, which is caused by the amphibian chytrid fungus Batrachochytrium dendrobatidis, and is implicated in population declines in over 500 frog species. Thought to originate in Asia, B. dendrobatidis now has a global distribution, likely due to human movement and trade. The pathogen has yet to be detected in Melanesia, but there have been few surveys for B. dendrobatidis in the region, and none in the Solomon Islands archipelago, a biogeographic region with a unique and culturally important frog fauna. We swabbed 200 frogs of eight species in three genera in lowland and highland sites in East Kwaio on the island of Malaita in the Solomon Islands. All frogs tested negative for the pathogen but it is possible that the pathogen is present despite non-detection, so further surveys for the pathogen are needed throughout the country. Despite this, it is safest to take a precautionary approach and assume that B. dendrobatidis has not yet been introduced to the Solomon Islands, and that naïve native amphibian populations may be at risk of decline if the pathogen is introduced. Protocols are needed to prevent the accidental import of infected frogs via tourism or in logging or mining equipment. Monitoring of frog populations near areas of high risk such as ports is also recommended. The frogs of the Solomon Islands archipelago are biologically unique and culturally significant, and protecting them from the potentially devastating impacts of B. dendrobatidis is vital