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Legal Aspects of Land Use Regulation of Lake Shorelands by State and Local Governments for the Protection of Lakes
U.S. Department of the Interior Office of Water Research and TechnologyCenter for Water and the Environmen
Distributed Approximation of Minimum Routing Cost Trees
We study the NP-hard problem of approximating a Minimum Routing Cost Spanning
Tree in the message passing model with limited bandwidth (CONGEST model). In
this problem one tries to find a spanning tree of a graph over nodes
that minimizes the sum of distances between all pairs of nodes. In the
considered model every node can transmit a different (but short) message to
each of its neighbors in each synchronous round. We provide a randomized
-approximation with runtime for
unweighted graphs. Here, is the diameter of . This improves over both,
the (expected) approximation factor and the runtime
of the best previously known algorithm.
Due to stating our results in a very general way, we also derive an (optimal)
runtime of when considering -approximations as done by the
best previously known algorithm. In addition we derive a deterministic
-approximation
Changes in Smoking Behaviours Following a Smokefree Legislation in Parks and on Beaches: An Observational Study
OBJECTIVE: To examine the effect of an outdoor smokefree law in parks and on beaches on observed smoking in selected venues.
METHODS: The study involved repeated observations in selected parks and beaches in Vancouver, British Columbia, Canada. The main outcome measure was changes in observed smoking rates in selected venues from prelaw to 12 months postlaw.
RESULTS: No venue was 100% smokefree at the 12-month postlaw observation time point. There was a significant decrease in observed smoking rates in all venues from prelaw to 12-month postlaw (prelaw mean smoking rate=20.5 vs 12-month mean smoking rate=4.7, p=0.04). In stratified analysis by venue, the differences between the prelaw and 12-month smoking rates decreased significantly in parks (prelaw mean smoking rate=37.1 vs 12-month mean smoking rate=6.5, p=0.01) but not in beaches (prelaw mean smoking rate=2.9 vs 12-month mean smoking rate=1.0, p=0.1).
CONCLUSIONS: Smokefree policies in outdoor recreational venues have the potential to decrease smoking in these venues. The effectiveness of such policies may differ by the type and usage of the venue; for instance, compliance may be better in venues that are used more often and have enforcement. Future studies may further explore factors that limit and foster the enforcement of such policies in parks and beaches
Effects of a Smoke-free Law in Parks and Beaches on Smoking Behaviour: Methods to Determine Effectiveness (2011)
As part of a comprehensive approach to tobacco control,smoke free laws have resulted in reductions of indoor air pollution, improvements in respiratory and cardiovascular health, reduction of smoking uptake by youth, and increasing tobacco use cessation in various jurisdictions. Although many studies have demonstrated the beneficial effects of smoke-free policies in indoor spaces (e.g., restaurants, bars, workplaces, hospital settings, etc.), little is known about the effectiveness of such policies in outdoor public spaces. On September 1st, 2010, Vancouver’s smoke-free by-law for the city’s parks, beaches, and facilities came into effect. The aims of this study are two-fold: a) to examine the effect of this smoke-free law on the frequency of smoking in selected parks and beaches, and b) to determine the change in location of smoking, within parks and beaches, following the enactment of the smoke-free law. The hypotheses guiding this study are: 1) There will be a lower frequency of observed smoking behaviour following the introduction of the law and 2) Smoking behaviour will be dispersed to the peripheries (i.e., margins) of the parks and beaches, following the enactment of the smoke-free law
Effects of a Smoke-free Law in Parks and Beaches on Smoking (2012)Behaviour: Methods to Determine Effectiveness
OVERVIEW
As part of a comprehensive approach to tobacco control, smoke free laws have resulted in reductions of indoor air pollution, improvements in respiratory and cardiovascular health, reduction of smoking uptake by youth, and increasing tobacco use cessations in various jurisdictions.
Although many studies have demonstrated the beneficial effects of smoke-free policies in indoor spaces (e.g. restaurants, bars, workplaces, hospital settings, etc.), little is known about the effectiveness of such policies in outdoor public spaces.
On September 1st, 2010, Vancouver’s smoke-free by-law for the city’s parks, beaches, and facilities came into effect.
The aims of this study are two-fold.
a) To examine the effect of this smoke-free law on the frequency of smoking in selected parks and beaches, and
b) To determine the change in location of smoking, within parks and beaches, following the enactment of the smoke-free law.
The hypotheses guiding this study are:
1. There will be a lower frequency of observed smoking behaviour following the introduction of the law and
2. Smoking behaviour will be dispersed to the peripheries (i.e. margins) of the parks and beaches, following the enactment of the smoke-free law
Effects of a Smoke-free Law in Parks and Beaches on Smoking Behaviour: Methods to Determine Effectiveness
OVERVIEW
As part of a comprehensive approach to tobacco control, smoke free laws have resulted in reductions of indoor air pollution, improvements in respiratory and cardiovascular health, reduction of smoking uptake by youth, and increasing tobacco use cessations in various jurisdictions.
Although many studies have demonstrated the beneficial effects of smoke-free policies in indoor spaces (e.g. restaurants, bars, workplaces, hospital settings, etc.), little is known about the effectiveness of such policies in outdoor public spaces.
On September 1st, 2010, Vancouver’s smoke-free by-law for the city’s parks, beaches, and facilities came into effect.
The aims of this study are two-fold.
a) To examine the effect of this smoke-free law on the frequency of smoking in selected parks and beaches, and
b) To determine the change in location of smoking, within parks and beaches, following the enactment of the smoke-free law.
The hypotheses guiding this study are:
1. There will be a lower frequency of observed smoking behaviour following the introduction of the law and
2. Smoking behaviour will be dispersed to the peripheries (i.e. margins) of the parks and beaches, following the enactment of the smoke-free law
Effects of a Smoke-free Law in Parks and Beaches on Smoking Behaviour: Methods to Determine Effectiveness
As part of a comprehensive approach to tobacco control,smoke free laws have resulted in reductions of indoor air pollution, improvements in respiratory and cardiovascular health, reduction of smoking uptake by youth, and increasing tobacco use cessation in various jurisdictions. Although many studies have demonstrated the beneficial effects of smoke-free policies in indoor spaces (e.g., restaurants, bars, workplaces, hospital settings, etc.), little is known about the effectiveness of such policies in outdoor public spaces. On September 1st, 2010, Vancouver’s smoke-free by-law for the city’s parks, beaches, and facilities came into effect. The aims of this study are two-fold: a) to examine the effect of this smoke-free law on the frequency of smoking in selected parks and beaches, and b) to determine the change in location of smoking, within parks and beaches, following the enactment of the smoke-free law. The hypotheses guiding this study are: 1) There will be a lower frequency of observed smoking behaviour following the introduction of the law and 2) Smoking behaviour will be dispersed to the peripheries (i.e., margins) of the parks and beaches, following the enactment of the smoke-free law
Changes in Smoking Behaviours Following a Smokefree Legislation in Parks and on Beaches: An Observational Study
OBJECTIVE: To examine the effect of an outdoor smokefree law in parks and on beaches on observed smoking in selected venues.
METHODS: The study involved repeated observations in selected parks and beaches in Vancouver, British Columbia, Canada. The main outcome measure was changes in observed smoking rates in selected venues from prelaw to 12 months postlaw.
RESULTS: No venue was 100% smokefree at the 12-month postlaw observation time point. There was a significant decrease in observed smoking rates in all venues from prelaw to 12-month postlaw (prelaw mean smoking rate=20.5 vs 12-month mean smoking rate=4.7, p=0.04). In stratified analysis by venue, the differences between the prelaw and 12-month smoking rates decreased significantly in parks (prelaw mean smoking rate=37.1 vs 12-month mean smoking rate=6.5, p=0.01) but not in beaches (prelaw mean smoking rate=2.9 vs 12-month mean smoking rate=1.0, p=0.1).
CONCLUSIONS: Smokefree policies in outdoor recreational venues have the potential to decrease smoking in these venues. The effectiveness of such policies may differ by the type and usage of the venue; for instance, compliance may be better in venues that are used more often and have enforcement. Future studies may further explore factors that limit and foster the enforcement of such policies in parks and beaches
Plasma formation from ultracold Rydberg gases
Recent experiments have demonstrated the spontaneous evolution of a gas of
ultracold Rydberg atoms into an expanding ultracold plasma, as well as the
reverse process of plasma recombination into highly excited atomic states.
Treating the evolution of the plasma on the basis of kinetic equations, while
ionization/excitation and recombination are incorporated using rate equations,
we have investigated theoretically the Rydberg-to-plasma transition. Including
the influence of spatial correlations on the plasma dynamics in an approximate
way we find that ionic correlations change the results only quantitatively but
not qualitatively
Gender Identity, Ethnic Identity, and Smoking among First Nations Adolescents
Smoking rates among Aboriginal adolescents are the highest of any population group in British Columbia, Canada. Recent studies suggest that substance use is affected by gender and ethnic identity among youth. The purpose of our study was to explore the association of gender and ethnic identity with smoking behaviour among First Nations adolescents. This study is based on a convenience sample (i.e., an on-hand, readily available sample) of 124 youth (123 First Nations and 1 Métis) recruited at youth drop-in centres, health fairs, and cultural activities. We obtained information on demographics, smoking history, Bem Sex Role Inventory (BSRI), composite measure of gender and gender identification (GID), and Moran’s Bicultural Ethnic Identity Questionnaire (Bicultural ID). We examined the associations between gender role identification and cultural identification on current smoking status among First Nations youth by using logistic regression analyses stratified by gender. In stratified multivariate regression analysis among girls, current smoking was significantly associated with lower scores on the aggressive masculinity index of the Gender ID scale and the White/Canadian index of the Bicultural ID scale. Among boys, current smoking was significantly associated with higher scores on the affective femininity index of the Gender ID scale and lower scores on the White/Canadian index of the Bicultural ID scale. Reducing smoking among First Nations groups remains an important priority for tobacco control in Canada. Understanding the gendered and cultural aspects of smoking may be instrumental in improving prevention and cessation efforts among First Nations youth
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