Secondary prevention of excessive alcohol use: assessing the prospects of implementation

BACKGROUND: Alcohol risk and harm reduction is a public health approach that goes beyond specialized treatments for alcoholism. The greatest potential for reducing alcohol risk and harm in a population depends on the extent to which health care practitioners use secondary prevention programmes. OBJECTIVE: We aim to assess the factors that affect the prospects of disseminating comprehensive, secondary prevention programmes into mainstream practice. METHOD: A decision balance was used to assess the prospects of practitioners implementing comprehensive programmes systematically. The stages-of-change model provides perspectives about behaviour change with regard to patients, practitioners and practice settings. RESULTS AND CONCLUSIONS: Programme implementation is extremely unlikely given the current organization of health care settings. To maintain the use of such programmes, we need to change the "unit of leverage" in the system: from the clinical encounter--that is, practitioners working with individual patients in a case-finding manner--to an organizational level--that is, the appropriate use of managerial and information systems supporting health care settings to identify at-risk patients systematically as they enter primary care and hospital settings. With appropriate infrastructure support, practitioners will be able to fulfil the potential for as well as maintain the use of comprehensive, secondary prevention programmes to reduce alcohol risk and harm in the population.     

Associations between family cohesion and adolescent siblings' externalizing behavior.

This study asked whether family cohesion, a measure of whole family functioning, was associated with adolescent siblings' externalizing problems, controlling for the quality of each sibling's relationship with his or her parents. The sample included 93 families (mothers, fathers, and 2 adolescent siblings). Family cohesion was measured from videotaped observations of parents and 2 of their adolescent children discussing family conflict and limit setting. Adolescents reported on hostility in their relationships with mothers and fathers, and parents rated adolescents' externalizing problems. Results from multilevel modeling showed that family cohesion was negatively associated with adolescents' externalizing problems, independent of variance explained by hostility in dyadic parent-child relationships. Results support family systems theory, suggesting that whole family functioning has implications for adolescents' behavioral problems beyond those accounted for by dyadic family relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of nicotine on negative affect among more impulsive smokers.

In the present study, the authors tested the hypothesis that nicotine would provide greater relief from negative affect for more impulsive smokers than for less impulsive smokers. Euthymic adult smokers (N=70) participated in 2 laboratory sessions, during which they underwent a negative mood induction (music + autobiographical memory), then smoked either a nicotinized or de-nicotinized cigarette. Mixed-effects regression yielded a significant Impulsivity × Condition (nicotinized vs. de-nicotinized) × Time interaction. Simple effects analyses showed that heightened impulsivity predicted greater negative affect relief after smoking a nicotinized cigarette but not after smoking a de-nicotinized cigarette. These data suggest that nicotine may be a disproportionately powerful negative reinforcer for highly impulsive smokers, promoting higher levels of nicotine dependence and inhibiting smoking cessation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recruitment properties of intramuscular and nerve-trunk stimulating electrodes.

Functionally useful reanimation of paralyzed limbs generally requires reliable, finely graded control of muscle recruitment and force with minimal fatigue. We used force and electromyographic (EMG) recordings in combination with myofibrillar adenosine triphosphatase activity and glycogen depletion analysis to investigate the recruitment properties of intramuscular (IM) and nerve cuff (NC) stimulating electrodes implanted acutely or chronically in cat hindlimbs. Overall, 32 muscles were submaximally stimulated with current intensities producing approximately 20% of maximal twitch force using 330 ms trains of pulses at 20 and 40 pps. Both the glycogen-depletion and fatigue-test results were found to be difficult to interpret because NC stimulation resulted in surprisingly unstable recruitment during such trains. Fluctuations of force and M-waves within trains of identical stimuli were significantly greater for NC than for IM stimulation. NC stimulation produced much steeper recruitment curves and a reduced tetanus/twitch ratio compared to IM stimulation. IM stimulation produced more reliable and less fatigable recruitment of a mix of motor unit types that tended to be localized in neuromuscular compartments containing, or adjacent to, the IM electrode. We hypothesize that trains of submaximal stimulation applied through NC electrodes resulted in fluctuating recruitment because this electrode configuration magnifies the effects of refractoriness and small changes in axonal excitability during pulse trains.     

Modelling batch bioreactions with continuous process simulators

Process models are increasingly becoming necessary for process understanding and optimizing. However, in the field of bioprocessing, modelling using a generic process simulator suffers from shortcomings given that many simulators cannot model batch mode bioreactors with varying reaction rates based on microbial metabolism. Bioprocesses, mostly batch, are difficult to model because most of the available unit operations in process simulators operate continuously. Our aim is to provide a general simulation platform to model these batch bioprocesses in commercial process simulators and explain how to transform batch processes with varying reaction rate into continuous unit operations for simulation purposes. Two typical fermentation processes, lactose fermentation and glucose/xylose co-fermentation, were simulated in steady state as case studies. The results are discussed as examples using the proposed approach. The potential of how to extend the simulation platform is also explained in detail.     

Exploring the impact of a dedicated streetcar right-of-way on pedestrian motor vehicle collisions: A quasi experimental design

Background and Objectives

The frequency of pedestrian collisions is strongly influenced by the built environment, including road width, street connectivity and public transit design. In 2010, 2159 pedestrian collisions were reported in the City of Toronto, Canada with 20 fatalities. Previous studies have reported that streetcars operating in mixed traffic pose safety risks to pedestrians; however, few studies evaluate the effects on pedestrian-motor vehicle collisions (PMVC). The objective of this study was to examine changes in the rate and spatial patterning of PMVC, pre to post right-of-way (ROW) installation of the St. Clair Avenue West streetcar in the City of Toronto, Canada.

Methods

A quasi-experimental design was used to evaluate changes in PMVC rate, following implementation of a streetcar ROW. Collision data were extracted from all police-reported PMVC, complied and verified by the City of Toronto, from January 1, 2000 to December 31, 2011. A zero-inflated Poisson regression analysis estimated the change in PMVC, pre to post ROW. Age and injury severity were also examined. Changes in the spatial pattern of collisions were examined by applying the G function to describe the proportion of collision events that shared a nearest neighbor distance less than or equal to a threshold distance.

Results

A total of 23,607 PMVC occurred on roadways during the study period; 441 occurring on St. Clair Ave, 153 during the period of analysis. There was a 48% decrease in the rate of collisions on St. Clair [Incidence rate ratio (IRR) = 0.52, 95% CI: 0.37–0.74], post ROW installation. There were also decreases noted for children (IRR = 0.13, 95% CI: 0.04–0.44), adults (IRR = 0.61, 95% CI: 0.38–0.97), and minor injuries (IRR = 0.56, 95% CI: 0.40–0.80). Spatial analyses indicated increased dispersion of collision events across each redeveloped route segment following the changes in ROW design.

Conclusions/Implications

Construction of a raised ROW operating on St. Clair Ave. was associated with a reduction in the rate of collisions. Differences in pre- and post collision spatial structure indicated changes in collision locations. Results from this study suggest that a streetcar ROW may be a safer alternative for pedestrians compared to a mixed traffic streetcar route and should be considered by city planners where appropriate to the street environment.