4,951 research outputs found
DNA repair: Knockouts still mutating after first round
AbstractRecent studies have investigated whether particular DNA repair pathways are involved in the somatic hypermutation mechanism that increases antibody diversity. The primary mutation mechanism still functions in mice carrying knockouts of all repair genes examined, but mismatch repair defects affect the final outcome
Internet Gambling: An Overview of Psychosocial Impacts
Technological innovation has always played a role in the development of gambling behaviour, primarily through providing new market opportunities. Early prevalence studies of Internet gambling in the UK, Canada and the US have shown that Internet gambling is not a cause for concern at present However, this seems likely to change as more people start to use the Internet for leisure activities. After a brief overview of gambling technologies and deregulation issues, this paper examines the impact of technology on gambling by highlighting salient factors in the rise of Internet gambling (i.e., accessibility, affordability, anonymity, convenience, escape immersion/dissociation, disinhibition, event frequency, asociability, interactivity, and simulation). The paper also overviews some of the main social impacts surrounding Internet gambling, such as protection of the vulnerable, Internet gambling in the workplace, electronic cash, and unscrupulous operators. Recommendations for Internet gambling operators are also provided
Marginal states of the resistive tearing mode with flow in cylindrical geometry
The linear stability of tearing modes in a cylindrical plasma subject to a sub-Alfvénic equilibrium shear flow along the equilibrium magnetic field is considered. The equations in the resistive boundary layer at the rational surface are solved numerically using a Fourier transform combined with a finite-element approach. The behaviour of the growth rate as a function of the flow and the various parameters (including a perpendicular fluid viscosity) is obtained. Marginal stability curves showing the dependence of the familiar matching parameter Δ' with flow and shear are also given
Updating predictive accident models of modern rural single carriageway A-roads
Reliable predictive accident models (PAMs) are essential to design and maintain safe road networks and yet the models most commonly used in the UK were derived using data collected 20 to 30 years ago. Given that the national personal injury accident total fell by some 30% in the last 25 years, while road traffic increased by over 60%, significant errors in scheme appraisal and evaluation based on the models currently in use seem inevitable. In this paper the temporal transferability of PAMs for modern rural single carriageway A-roads is investigated and their predictive performance is evaluated against a recent data set. Despite the age of these models, the PAMs for predicting the total accidents provide a remarkably good fit to recent data and these are more accurate than models where accidents are disaggregated by type. The performance of the models can be improved by calibrating them against recent data
U.S. District Court Directs FDA to Reevaluate Previous Plan B Decision
Judge Edward R. Korman of the U.S. District Court, Eastern District of New York, issued a decision today (Mar. 23, 2009) in the case of Annie Tummino et al v. Frank M. Torti, Acting Commissioner of the Food and Drug Administration. The case involved plaintiffs\u27 claims that the FDA, in deciding that Plan B, known as emergency contraception or the morning-after pill, be made available over-the-counter (OTC) only with age restrictions, was unduly and inappropriately influenced by pressures from the White House among other factors
Aerodynamic and propeller performance characteristics of a propfan-powered, semispan model
A semispan wing/body model with a powered propeller was tested to provide data on a total powerplant installation drag penalty of advanced propfan-powered aircraft. The test objectives were to determine the total power plant installation drag penalty on a representative propfan aircraft; to study the effect of configuration modifications on the installed powerplant drag; and to determine performance characteristics of an advanced design propeller which was mounted on a representative nacelle in the presence of a wing
- …