5,315 research outputs found
Socioeconomic Differences in the Impact of Smoking Tobacco and Alcohol Prices on Smoking in India
The threat posed by smoking to health in India is severe. Already 1 in 5 of all adult male deaths and 1 in 20 of all adult female deaths at ages 30-69 are due to smoking and India will soon have 1 million smoking deaths a year. Increasing tobacco prices has been found to be the single most effective method to reduce smoking. Yet, bidis, the most common form of smoked tobacco in India, are largely untaxed, while cigarettes are taxed at about 40% of retail price, well below the 65–80% rate noted by the World Bank in countries with effective tobacco control policies. Moreover, low and stagnant tax rates have occurred in a period in which all tobacco products have become more affordable with income growth. First, we use data from the most recent three consecutive quinquennial National Sample Survey (NSS) rounds (NSS 50, 55 and 61 conducted in 1993/94, 1999/00 and 200/05) and a two-equation system of budget shares and unit values that attempts to correct for quality and measurement error. Second, we pool data from the most recent nine rounds of NSS (NSS 55-57, 59-64, conducted between 1999/00 to 2007/08). Our analyses of single and repeated cross-sections yield own-price elasticity for bidis that are roughly in keeping with existing evidence. We find that a 10% increase in bidi prices would reduce the demand for bidis by about 6 to 9.5%. We find, however, that own-price elasticity for cigarettes in India is substantially larger than previously thought. Our estimates suggest that cigarette users are at least as responsive as bidi users to price changes. On the whole, our analyses suggest that low SES households are likely more responsive to price changes than high SES households. Our analyses also uncovers important and policy-relevant cross-prices effects. Findings from this study provide additional evidence of the effectiveness of tobacco prices at reducing tobacco use.
On the Slope-Aspect Correction of Multispectral Scanner Data
The effects of topography on the radiometric properties of multispectral scanner (MSS) data are examined in the context of the remote sensing of forests in mountainous regions. The two test areas considered for this study are located in the coastal mountains of British Columbia, one at the Anderson River near Boston Bar and the other at Gun Lake near Bralorne. The predominant forest type at the former site is Douglas fir, whereas forest types at the latter site are primarily lodgepole pine and ponderosa pine. Both regions have rugged topography, with elevations ranging from 275 to 1500 metres above sea level at Anderson River and from 670 to 1990 metres above sea level at Gun Lake.
Lambertian and non-Lambertian illumination corrections are formulated, taking into account atmospheric effects as well as topographic variations. Terrain slope and aspect values are determined from a digital elevation model and atmospheric parameters are obtained from a model atmosphere computation for the solar angles and spectral bands of interest. In the Lambertian approximation, if sky irradiance and atmospheric path radiance are neglected, one is left with a cosine correction analogous to the one which has been used extensively to carry out illumination transformations of images of horizontal terrain. However, this extension of the simple cosine correction to the case of sloped terrain is shown to be inadequate, especially for larger angles of incidence.
Attempts are also made to remove the effect of topography by means of semi-empirical functions primarily based on cosines of the incident and reflected illumination angles. In this vein, correlations and linear regressions between topographic parameters (such as elevation, slope, aspect, incidence angle, reflection angle) and MSS radiance values are investigated for the different forest types under consideration at each site.
The analysis encompasses multitemporal Landsat MSS data at a resolution of 50 metres and 11 channel airborne MSS at resolutions of 20 and 50 metres. Slope aspect correction algorithms for both of these types of data are implemented in software on the image analysis system at the Canada Centre for Remote Sensing. Geometric rectification is also a prerequisite in order to relate image geometry to the map coordinates on which the digital terrain data are based. A special technique involving flight line modelling is used to accomplish this in the case of aircraft data since prior knowledge of the terrain elevation is needed for each image pixel in order to establish an undistorted transformation.
Feature selection based on divergence criteria indicates that terrain parameters compare favourably with the MSS data in terms of ability to distinguish between forest classes. However, maximum likelihood classification results for MSS data, corrected for slope-aspect effects using a variety of functions, show little or no significant improvement over results obtained using uncorrected data. This outcome is discussed with a view to achieving a better understanding of both the physical principles and the image processing methodologies involved
CCRS proposal for evaluating LANDSAT-4 MSS and TM data
The measurement of registration errors in LANDSAT MSS data is discussed as well as the development of a revised algorithm for the radiometric calibration of TM data and the production of a geocoded TM image
Parvovirus-derived endogenous viral elements in two South American rodent genomes
We describe endogenous viral elements (EVEs) derived from parvoviruses (family
<i>Parvoviridae</i>) in the long-tailed chinchilla (<i>Chinchilla lanigera</i>) and degu (<i>Octodon degus</i>)
genomes. The novel EVEs include Dependovirus-related elements, and representatives of a
clearly distinct parvovirus lineage that also has endogenous representatives in marsupial
genomes. In the degu, one dependovirus-derived EVEs was found to encode an intact reading
frame, and was differentially expressed <i>in vivo</i>, with increased expression in the liver
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Cigarette packaging, warnings, prices, and contraband: A discrete choice experiment among smokers in Ontario, Canada
In Canada, despite substantial decline, tobacco use remains the leading risk factor responsible for mortality and morbidity. There is overwhelming evidence that higher tobacco taxes reduce tobacco use, even if high taxes create an incentive to avoid or evade tobacco taxes. Recently, in addition to taxes, plain and standardized packaging and printing a warning on each cigarette have been lauded to reduce tobacco use. In November 2019, Canada became the country with the most comprehensive cigarette packaging regulations; and in June 2022, Canada proposed to print health warnings on individual cigarettes, the first jurisdiction to ever do so. The regulations came into force on August 1, 2023, and are being implemented through a stepwise approach. Our objective was to examine the effects of plain and standardized packaging, warning on cigarettes, price, and the availability of illicit cigarettes on intention to purchase and risk perceptions. We conducted a discrete choice experiment, and examined heterogeneity in preferences using latent class models among smokers in Ontario, Canada. We found that using latent class analyses was essential in quantifying preferences for attributes of cigarettes and cigarette packs. First, nearly half of smokers stated a preference for cheaper illicit cigarettes in a branded pack without any health warnings, regardless of the licit cigarette alternatives. For about 20% of respondents, plain packaging and especially warning on cigarette sticks decreased the probability of stating a purchasing preference for these alternatives. Third, about a third of respondents chose competing alternatives with mostly one attribute in mind, price. Lastly, none of the products and attributes seem to have significantly influenced risk perception. Our findings attest to the importance of prices and taxes, to the potential of warnings on cigarette sticks to control tobacco use, and indicate that efforts to restrict the availability of illicit cigarettes may yield substantial benefits
Bridging the gaps among research, policy and practice in ten low- and middle-income countries: Development and testing of a questionnaire for researchers
<p>Abstract</p> <p>Background</p> <p>A questionnaire could assist researchers, policymakers, and healthcare providers to describe and monitor changes in efforts to bridge the gaps among research, policy and practice. No questionnaire focused on researchers' engagement in bridging activities related to high-priority topics (or the potential correlates of their engagement) has been developed and tested in a range of low- and middle-income countries (LMICs).</p> <p>Methods</p> <p>Country teams from ten LMICs (China, Ghana, India, Iran, Kazakhstan, Laos, Mexico, Pakistan, Senegal, and Tanzania) participated in the development and testing of a questionnaire. To assess reliability we calculated the internal consistency of items within each of the ten conceptual domains related to bridging activities (specifically Cronbach's alpha). To assess face and content validity we convened several teleconferences and a workshop. To assess construct validity we calculated the correlation between scales and counts (i.e., criterion measures) for the three countries that employed both and we calculated the correlation between different but theoretically related (i.e., convergent) measures for all countries.</p> <p>Results</p> <p>Internal consistency (Cronbach's alpha) for sets of related items was very high, ranging from 0.89 (0.86-0.91) to 0.96 (0.95-0.97), suggesting some item redundancy. Both face and content validity were determined to be high. Assessments of construct validity using criterion-related measures showed statistically significant associations for related measures (with gammas ranging from 0.36 to 0.73). Assessments using convergent measures also showed significant associations (with gammas ranging from 0.30 to 0.50).</p> <p>Conclusions</p> <p>While no direct comparison can be made to a comparable questionnaire, our findings do suggest a number of strengths of the questionnaire but also the need to reduce item redundancy and to test its capacity to monitor changes over time.</p
Assessing healthcare providers' knowledge and practices relating to insecticide-treated nets and the prevention of malaria in Ghana, Laos, Senegal and Tanzania
Abstract
Background
Research evidence is not always being disseminated to healthcare providers who need it to inform their clinical practice. This can result in the provision of ineffective services and an inefficient use of resources, the implications of which might be felt particularly acutely in low- and middle-income countries. Malaria prevention is a particularly compelling domain to study evidence/practice gaps given the proven efficacy, cost-effectiveness and disappointing utilization of insecticide-treated nets (ITNs).
Methods
This study compares what is known about ITNs to the related knowledge and practices of healthcare providers in four low- and middle-income countries. A new questionnaire was developed, pilot tested, translated and administered to 497 healthcare providers in Ghana (140), Laos (136), Senegal (100) and Tanzania (121). Ten questions tested participants' knowledge and clinical practice related to malaria prevention. Additional questions addressed their individual characteristics, working context and research-related activities. Ordinal logistic regressions with knowledge and practices as the dependent variable were conducted in addition to descriptive statistics.
Results
The survey achieved a 75% response rate (372/497) across Ghana (107/140), Laos (136/136), Senegal (51/100) and Tanzania (78/121). Few participating healthcare providers correctly answered all five knowledge questions about ITNs (13%) or self-reported performing all five clinical practices according to established evidence (2%). Statistically significant factors associated with higher knowledge within each country included: 1) training in acquiring systematic reviews through the Cochrane Library (OR 2.48, 95% CI 1.30-4.73); and 2) ability to read and write English well or very well (OR 1.69, 95% CI 1.05-2.70). Statistically significant factors associated with better clinical practices within each country include: 1) reading scientific journals from their own country (OR 1.67, 95% CI 1.10-2.54); 2) working with researchers to improve their clinical practice or quality of working life (OR 1.44, 95% CI 1.04-1.98); 3) training on malaria prevention since their last degree (OR 1.68, 95% CI 1.17-2.39); and 4) easy access to the internet (OR 1.52, 95% CI 1.08-2.14).
Conclusions
Improving healthcare providers' knowledge and practices is an untapped opportunity for expanding ITN utilization and preventing malaria. This study points to several strategies that may help bridge the gap between what is known from research evidence and the knowledge and practices of healthcare providers. Training on acquiring systematic reviews and facilitating internet access may be particularly helpful
Association of tobacco control policies with youth smoking onset in Chile
South American countries, and Chile in particular, endure some of the highest cigarette smoking prevalence rates globally. Despite the lack of any meaningful increases in cigarette taxes (the most effective tobacco control measure), between 1999 and 2014 cigarette prices in Chile increased sharply almost entirely driven by British American Tobacco (BAT). Findings suggest that higher prices initiated by BAT and the tobacco control policies enacted by the Ministry of Health (2006) were associated with lower hazards of starting smoking in Chilean youth. A large cigarette tax increase can be used strategically to reduce smoking among youth in Chile
Phylogeny.fr: robust phylogenetic analysis for the non-specialist
Phylogenetic analyses are central to many research areas in biology and typically involve the identification of homologous sequences, their multiple alignment, the phylogenetic reconstruction and the graphical representation of the inferred tree. The Phylogeny.fr platform transparently chains programs to automatically perform these tasks. It is primarily designed for biologists with no experience in phylogeny, but can also meet the needs of specialists; the first ones will find up-to-date tools chained in a phylogeny pipeline to analyze their data in a simple and robust way, while the specialists will be able to easily build and run sophisticated analyses. Phylogeny.fr offers three main modes. The ‘One Click’ mode targets non-specialists and provides a ready-to-use pipeline chaining programs with recognized accuracy and speed: MUSCLE for multiple alignment, PhyML for tree building, and TreeDyn for tree rendering. All parameters are set up to suit most studies, and users only have to provide their input sequences to obtain a ready-to-print tree. The ‘Advanced’ mode uses the same pipeline but allows the parameters of each program to be customized by users. The ‘A la Carte’ mode offers more flexibility and sophistication, as users can build their own pipeline by selecting and setting up the required steps from a large choice of tools to suit their specific needs. Prior to phylogenetic analysis, users can also collect neighbors of a query sequence by running BLAST on general or specialized databases. A guide tree then helps to select neighbor sequences to be used as input for the phylogeny pipeline. Phylogeny.fr is available at: http://www.phylogeny.fr
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