The Role of Simple Rules in the Conduct of Canadian Monetary Policy

The third strategy employed by the Bank when dealing with uncertainty is the consideration of appropriate simple reaction functions or "rules" for the setting of the policy interest rate. Since John Taylor's presentation of his much-discussed rule, research on simple policy rules has exploded. Simple rules have several advantages. In particular, they are easy to construct and communicate and are believed by some to be robust, in the sense of generating good results in a variety of economic models. This article provides an overview of the recent research regarding the usefulness and robustness of simple monetary policy rules, particularly in models of the Canadian economy. It also describes and explains the role of simple rules in the conduct of monetary policy in Canada.

A case-control study on environmental and familial risk factors for colorectal cancer in Hong Kong: physical activity reduces colorectal cancer risk

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A case-control study on environmental and familial risk factors for colorectal cancer in Hong Kong: dietary determinants of colorectal cancer risk

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Improving an interactive simulator for computer systems with learning objects

In the 21st century, learning is a crucial activity through which people can assimilate or acquire new knowledge. However, many existing e-Iearning systems contain complicated knowledge structure that hinders the reuse or sharing of knowledge. In a previous project awarded by the Microsoft Research Asia, we successfully developed an interactive simulator to facilitate the learning of essential concepts related to computer systems through live animations. Here, we propose to integrate learning objects and relevant technologies into our interactive simulator to illustrate the underlying knowledge structure and, more importantly, facilitate the sharing and reuse of relevant concepts. Through adopting the IEEE learning object metadata (LOM) standard, our simulator can easily exchange relevant learning objects with other e-Iearning systems. The system design and prototype implementation of our LOM-based simulator is considered in this paper to evaluate how general and experienced users can benefit from our LOM-based simulator in various ways. © 2010 IEEE.published_or_final_versionThe 2nd International Conference on Education Technology and Computer (ICETC 2010), Shanghai, China, 22-24 June 2010. In Proceedings of the International Conference on Education Technology and Computer, 2010, v. 3, p. 16-2

A case-control study on environmental and familial risk factors for colorectal cancer in Hong Kong: chronic illnesses, medication and family history

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Toward a complete e-learning system framework for semantic analysis, concept clustering and learning path optimization

Most online e-learning systems often demand the pre-requisite requirements between course modules and/or some relationship measures between involved concepts to be explicitly inputed by the course instructors so that an optimizer can be ultimately used to find an optimal learning sequence of involved concepts or modules for each individual learner after considering his/her past performance, learner's profile, learning style, etc. However, relying solely on the course instructor's input on the relationship among the involved concepts can be imprecise possibly due to the individual biases by human experts. Furthermore, the decision will become more complicated when various instructors hold conflicting views on the relationship among the involved concepts that may hinder any reasonable deduction. Therefore, we propose in this paper a complete system framework that can perform an explicit semantic analysis on the course materials, possibly aided by the relevant Wiki articles for any missing information about the involved concepts, to formulate the individual concepts, and followed by a heuristic-based concept clustering algorithm to group relevant concepts before finding their relationship measures. Lastly, an evolutionary optimizer will be used to return the optimal learning sequence after considering multiple experts' recommended learning sequences possibly containing conflicting views. To demonstrate the feasibility of our prototype, we implemented a prototype of the proposed e-learning system framework. Our empirical evaluation clearly revealed the possible advantages of our proposal with many possible directions for future investigation. © 2012 IEEE.published_or_final_versio

Applying an evolutionary approach for learning path optimization in the next-generation e-learning systems

Learning analytics is targeted to better understand and optimize the process of learning and its environments through the measurement, collection and analysis of learners' data and contexts. To advise people's learning in a specific subject, most intelligent e-learning systems would require course instructors to explicitly input some prior knowledge about the subject such as all the pre-requisite requirements between course modules. Yet human experts may sometimes have conflicting views leading to less desirable learning outcomes. In a previous study, we proposed a complete system framework of learning analytics to perform an explicit semantic analysis on the course materials, followed by a heuristic-based concept clustering algorithm to group relevant concepts before finding their relationship measures, and lastly employing a simple yet efficient evolutionary approach to return the optimal learning sequence. In this paper, we carefully consider to enhance the original evolutionary optimizer with the hill-climbing heuristic, and also critically evaluate the impacts of various experts' recommended learning sequences possibly with conflicting views to optimize the learning paths for the next-generation e-learning systems. More importantly, the integration of heuristics can make our proposed framework more self-adaptive to less structured knowledge domains with conflicting views. To demonstrate the feasibility of our prototype, we implemented a prototype of the proposed e-learning system framework for learning analytics. Our empirical evaluation clearly revealed many possible advantages of our proposal with interesting directions for future investigation. © 2013 IEEE.published_or_final_versio

Inflammatory pseudotumor of the liver in association with a gastrointestinal stromal tumor: A case report

Inflammatory pseudotumor of the liver is a rare benign lesion that can mimic a malignant liver neoplasm. A case of inflammatory pseudotumor of the liver found in association with a malignant gastrointestinal stromal tumor (GIST) of the small bowel was reported. The inflammatory pseudotumor was misdiagnosed as a metastasis from the GIST by frozen section. A correct diagnosis was made only after histopathological examination of the paraffin section of the resected specimen. This case is particularly interesting because of the association of the two rare pathological entities and the diagnostic dilemma that arose 6from the similarity of their histological appearances. To our knowledge, this association has not been reported in the literature. Copyright © 2004 by The WJG Press.published_or_final_versio

Sea lice exposure to non-lethal levels of emamectin benzoate after treatments: a potential risk factor for drug resistance

The avermectin derivative emamectin benzoate (EMB) has been widely used by salmon industries around the world to control sea lice infestations. Resistance to this anti-parasitic drug is also commonly reported in these industries. The objective of this study was to quantify the number of sea lice potentially exposed to sub-lethal concentrations of EMB while fish clear the drug after treatments. We assessed juvenile sea lice abundance after 38 EMB treatments on six Atlantic salmon farms, in a small archipelago in British Colombia, Canada, between 2007 and 2018. We fitted a standard EMB pharmacokinetic curve to determine the time when fish treated with this product would have EMB tissue concentrations below the recommended target therapeutic level. During the study, we estimated that for each sea lice treatment there was, on average, an abundance of 0.12 juvenile sea lice per fish during the time period when the concentrations of EMB would have been lower than 60ppb, the recommended therapeutic treatment level for sea lice. The findings from this study on metaphylactic anti-parasitic treatments identify a potential driver for drug resistance in sea lice that should be further explored

The prevalence of Helicobacter pylori carrier rates among the healthy blood donors in Hong Kong

A serological assay was employed in this study to assess the Helicobacter pylori carrier rates among the healthy blood donors (all Chinese) in Hong Kong. The commercial kit for detecting anti-H. pylori antibody titres was found to have a sensitivity of 84% and a specificity of 85% by using the histochemistry results as the gold standard. Elevated anti-H. pylori antibody titres were observed in 42.4%, 53.2% and 72.2% of the healthy blood donors of age below 20, 21 to 30 and 31 to 40 years respectively. This indicates a steady rise of H. pylori carrier rates with age. The overall H. pylori prevalence rate was 54.9%. The positivity of H. pylori in teenagers appeared to be double that reported in Western countries. Whether this is related to the younger age of peptic ulcer presentation in Hong Kong compared with Western countries is not known. However, there was no significant difference of the H. pylori rates between males and females of each age group although a male predominance has been well established for peptic ulcer in Hong Kong.published_or_final_versio