University of Manitoba

About: University of Manitoba is a education organization based out in Winnipeg, Manitoba, Canada. It is known for research contribution in the topics: Population & Health care. The organization has 31888 authors who have published 66592 publications receiving 2095493 citations.

Battle of the network models: Epilogue

Abstract: Several models that can be used to optimally size water distribution pipes were applied to a hypothetical system. The results are summarized in this paper. The models produced solutions with costs that were within 10% of one another, although the solutions were quite different. While the models were helpful in sizing pipes, some manual calculations and a good deal of engineering judgment were required to apply them.

Defining biocultural approaches to conservation

Abstract: We contend that biocultural approaches to conservation can achieve effective and just conservation outcomes while addressing erosion of both cultural and biological diversity. Here, we propose a set of guidelines for the adoption of biocultural approaches to conservation. First, we draw lessons from work on biocultural diversity and heritage, social-ecological systems theory, integrated conservation and development, co-management, and community-based conservation to define biocultural approaches to conservation. Second, we describe eight principles that characterize such approaches. Third, we discuss reasons for adopting biocultural approaches and challenges. If used well, biocultural approaches to conservation can be a powerful tool for reducing the global loss of both biological and cultural diversity.

Treatment of allergic rhinitis with intranasal corticosteroids in patients with mild asthma: Effect on lower airway responsiveness

Abstract: The effect of treatment of allergic rhinitis with intranasal corticosteroids on lower airway responsiveness was assessed in a randomized, double-blind, placebo-controlled, crossover study. Twenty-one young patients with perennial allergic rhinitis and asthma, with documented lower airway hyperresponsiveness (PC 20 methacholine 20 methacholine was performed at baseline and at the end of each treatment period. Intranasal beclomethasone dipropionate significantly reduced global rhinitis symptom scores ( p = 0.05) after 4 weeks of treatment. Global asthma scores did not change significantly ( p = 0.2). Geometric mean PC 20 methacholine improved significantly after 4 weeks of intranasal beclomethasone, but not after placebo ( p = 0.04). Daily morning and evening rhinitis symptom scores were lower in patients treated with intranasal corticosteroids over the first 4 weeks of treatment, but carryover effect of steroids precluded comparative analysis of the second 4-week block (morning p = 0.06, evening p = 0.03). Morning asthma scores tended to decrease ( p = 0.07). Evening asthma scores were significantly decreased at weeks 2 and 3 ( p = 0.001, p = 0.02, respectively). No change in peak expiratory flow rate was seen. This study confirms that treatment of inflammation in the upper airways indirectly improves asthma symptoms and decreases bronchial hyperreactivity. Ignoring inflammation in the upper airway may lead to suboptimal results in asthma treatment.

The Pharmacology and Use of H1-Receptor-Antagonist Drugs

Abstract: The second-generation H1-antagonist drugs are supplanting their predecessors in the treatment of allergic rhinoconjunctivitis and chronic urticaria. Their use can be justified mainly on the basis of a more favorable risk-benefit ratio, because they are less toxic to the central nervous system. Future research into H1 antagonists should include additional dose-response studies in patients with allergic disorders, especially children and the elderly; objective studies of adverse effects; studies of topical mucosal application of H1 antagonists; and studies of H1-antagonist enantiomers and active metabolites. With the cloning of the gene encoding the H1 receptor and increased understanding of the precise structural requirements for H1-receptor activity, H1 antagonists with an even more favorable therapeutic index may be developed.

Circularly Polarized Antennas

Abstract: This chapter is focused on circularly polarized antennas. Key definitions and governing equations of circular polarization are given. Infinitesimal dipole sources are considered to establish circularly polarized radiation. First, radiation patterns of cross dipoles are mathematically reviewed, from which the condition of circularly polarized waves is concluded. Later, the idea is extended to four displaced sequentially rotated dipole antennas, resulting in circularly polarized waves within a wide angular range in space. The extension of the concept to the magnetic source counterparts and Huygens sources is briefly discussed. Other than point sources, also known as one-dimensional current sources, sources of circularly polarized radiation are further investigated for two-dimensional cases, such as microstrip patch antennas, and threedimensional structures, such as volumetric current sources existing in dielectric resonator antennas. For these cases, the creation of circularly polarized radiation using single-feed and dual-feed, perturbed structures and sequentially rotated method is described. As a design example, numerical andmeasurement results of circularly polarized square patch ring antennas are extensively discussed and presented in this chapter. The square-ring microstrip antenna is selected as it closely approximates the sequentially rotated currents, and also it has not been widely studied in the literature.