Biocompatibility, SiH lenses and the impact of hydration on comfort

Silicone hydrogel (SiH) contact lenses have been available for over a decade. During that time, these highly innovative materials and designs have continually improved and now represent a major percentage of fits within the global contact lens market.1 Their high oxygen transmissibility has drastically reduced the incidence of hypoxia-related conditions such as corneal edema, limbal hyperaemia, and corneal vascularisation.2,3 However, there remain significant challenges in the quest for the ideal contact lens. The silicone material used in SiH contact lenses is inherently more hydrophobic than the non-silicone hydrogel materials. SiH lens manufacturers must find ways to overcome lens surface hydrophobicity since it can create issues in terms of lens wettability and surface deposition. Achieving ideal lens water content presents yet another challenge since increasing water content in a silicone hydrogel lens can reduce oxygen transmissibility. This is because increasing water content results in decreased silicone content in the lens and silicone is a better transmitter of oxygen than water.

Contact lens prescribing : USA vs the world

Along with other facets of commericialization, the contact lens market has become globalized during the past 30 years. The major international companies have worldwide distribution networks and supply lenses of the same product names and replacement frequencies to all nations, with a few minor adjustments for marketing and regulatory reasons. Small and medium-sized companies, often producing more specialized lenses, are also active in markets across the world.

Contact lens prescribing in Canada 2011

For the past 12 years, the International Contact Lens Prescribing Survey Consortium has sent surveys to a selection of Canadian optometrists in order to collect information on the contact lenses they fit and basic demographic data of the patients. Canada is one of about 40 countries that contributes to the global study and while annual reviews of the study data are presented, information published for any one market is limited due to the size of the dataset.1 This manuscript presents a more detailed analysis on the Canadian market for 2011.

Trends in contact lens prescribing 2012

The 13th annual survey of Australian contact lens prescribing was conducted between January and April 2012. The same format as in previous years was employed. About 3,000 members of Optometrists Association Australia were sent an e-mail message with a link to a downloadable questionnaire, and a request that this be accessed, printed and completed to provide details of the first 10 patients fitted with contact lenses after receipt of the questionnaire.

Contact Lens Complications [Third Edition]

"Contact Lens Complications has become established as the definitive guide to the ocular response to contact lens wear. In this highly anticipated third edition, award-winning contact lens author, clinician and researcher, Professor Nathan Efron, presents a thoroughly revised and expanded, clinician-friendly account of how to identify, understand and manage contact lens complications in modern-day practice. Professor Efron is renowned for his ability to distil often complex principles of ocular physiology and pathology into an easy-to-read, highly structured format. The subject matter is systematically laid out, with various complications arranged logically by tissue structure - which is the way practitioners naturally approach clinical problems. Beautifully presented and lavishly illustrated with full-colour schematic diagrams and clinical pictures, this book can serve as both a practical chair-side manual and authoritative reference."--publisher website

Criminal Laws : Materials and Commentary on Criminal Law and Process in NSW [Fifth Edition]

"The success of Criminal Laws lies both in its distinctive features and in its appeal to a range of readerships. As one review put it, it is simultaneously a "textbook, casebook, handbook and reference work". As such it is ideal for criminal law and criminal justice courses as a teaching text, combining as it does primary sources with extensive critical commentary and a contextual perspective. It is likewise indispensable to practitioners for its detailed coverage of substantive law and its extensive references and inter-disciplinary approach make it a first point of call for researchers from all disciplines. This fifth edition strengthens these distinctive features. All chapters have been systematically updated to incorporate the plethora of legislative, case law, statistical and research material which has emerged since the previous edition. The critical, thematic, contextual and interdisciplinary perspectives have been continued."--Publisher's website. Table of Contents: 1. Some themes -- 2. Criminalisation -- 3. The criminal process -- 4. Components of criminal offences -- 5. Homicide: murder and involuntary manslaughter -- 6. Defences -- 7. Assault and sexual assault -- 8. Public order offences -- 9. Drugs offences -- 10. Dishonest acquisition -- 11. Extending criminal liability: complicity, conspiracy and association -- 12. Sentencing and penality.

Experimental evaluation of an autonomous surface vehicle for water quality and greenhouse gas emission monitoring

This paper describes the experimental evaluation of a novel Autonomous Surface Vehicle capable of navigating complex inland water reservoirs and measuring a range of water quality properties and greenhouse gas emissions. The 16 ft long solar powered catamaran is capable of collecting water column profiles whilst in motion. It is also directly integrated with a reservoir scale floating sensor network to allow remote mission uploads, data download and adaptive sampling strategies. This paper describes the onboard vehicle navigation and control algorithms as well as obstacle avoidance strategies. Experimental results are shown demonstrating its ability to maintain track and avoid obstacles on a variety of large-scale missions and under differing weather conditions, as well as its ability to continuously collect various water quality parameters complimenting traditional manual monitoring campaigns.