In vitro degradation studies of devices fabricated from polylactic acid (PLA) and polyglycolic acid (PGA) are usually performed at the physiologic 37°C and often take long periods of time to complete. The objective of the present study was to examine the degradation of a 50:50 PLA-PGA copolymer over a wide temperature range (25°C to 80°C) and compare the degradation characteristics at temperatures below and above the polymer's glass transition temperature (T g ). Samples were fabricated using a solvent-casting technique and subjected to degradation in phosphate-buffered saline at the different test temperatures (T) for different periods of time. At the end of each test period, the samples were examined for changes in mass and molecular weight. The pH of the degradation media was also measured. Using the Arrhenius equation, activation energies were calculated for the degradation reaction. The results indicated that the rates of change of mass and molecular weight increased with increasing test temperatures. Activation energies for the degradation reaction at temperatures below and above the T g were distinctly different. Thus, it is recommended that tests performed at T > T g should not be used to predict degradation behavior at T < T g .

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This study describes the degradation behavior of biodegradable scaffolds fabricated from a copolymer of polylactic acid and polyglycolic acid using a new technique that eliminates some of the problematic issues with the salt-leaching technique. Two variations of this technique were used and the in vitro degradation characteristics of the resulting scaffolds were compared. The properties monitored included mass, molecular weight, porosity, permeability, mechanical stiffness, and polydispersity. The results indicated that the vibrating particle technique, results in scaffolds that are at least 90% porous and highly permeable. During degradation the porosity of the scaffolds initially decreased up to two weeks and then inceased. On the other hand, their stiffness first increased followed by a decrease. It was also determined that the permeability of the scaffolds can vary considerably without significant changes in the porosity.

Distracted driving caused by cellphone use is a significant source of needless injuries. These injuries place unnecessary financial burden, emotional stress and health care resource misuse on society. This paper states the Canadian Association of Emergency Physician's (CAEP's) position on cellphone use while driving. In recent years, numerous studies were conducted on the danger of cellphone use while driving. Research has shown that cellphone use while driving negatively impacts cognitive functions, visual fields, reaction time and overall driving performances. Some studies found that cellphone use is as dangerous as driving under the influence of alcohol. Moreover, vehicle crash rates were shown to be significantly higher when drivers used cellphones. Countermeasures have been implemented in recent years. Over 50 countries worldwide have laws limiting the use of cellphones while driving. Six Canadian provinces, Newfoundland and Labrador, Nova Scotia, Quebec, Ontario, British Columbia and Saskatchewan, currently have legislation prohibiting cellphone use. Other provinces are considering implementing similar bans. As emergency physicians, we must advocate for injury prevention. Cell phone related road traumas are avoidable. CAEP supports all measures to ban cellphone use while driving. CAEP POSITION The Canadian Association of Emergency Physicians recommends the following measures: 1. CAEP advocates for a total ban on hand-held and handsfree cellphone use while driving. 2. CAEP supports public awareness campaigns to inform people about the dangers of using cellphones and other hands-free electronic devices while driving. 3. CAEP supports discussions and seminars on the dangers of cellphone use while driving at future national conferences to raise awareness within the medical community. 4. CAEP supports continuing research into the danger of distracted driving. 5. CAEP supports legislations and policies banning all use of cellphones while driving.

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