Population parameters of Drosophila larval cooperative foraging.

Cooperative foraging behavior can be advantageous when there is a common exploitable resource. By cooperating, members of the group can take advantage of the potential of increased efficiency of working together as well as equitable distribution of the product. An experimental signature of cooperative foraging is an Allee effect where at a certain number of individuals, there is a peak of fitness. What happens when there are intruders especially ones that do not contribute to any work required for foraging? Drosophila larvae secrete digestive enzymes and exodigest food. Under crowded conditions in liquid food these larvae form synchronized feeding clusters which provides a fitness benefit. A key for this synchronized feeding behavior is the visually guided alignment between adjacent larvae in a feeding cluster. Larvae who do not align their movements are excluded from the groups and subsequently lose the benefit. This may be a way of editing the group to include only known members. To test the model, the fitness benefit from cooperative behavior was further investigated to establish an Allee effect for a number of strains including those who cannot exodigest or cluster. In a standard lab vial, about 40 larvae is the optimal number for fitness. Combinations of these larvae were also examined. The expectation was that larvae who do not contribute to exodigestion are obligate cheaters and would be expelled. Indeed, obligate cheaters gain greatly from the hosts but paradoxically, so do the hosts. Clusters that include cheaters are more stable. Therefore, clustering and the benefits from it are dependent on more than just the contribution to exodigestion. This experimental system should provide a rich future model to understand the metrics of cooperative behavior.

A decade of tobacco control efforts: Implications for tobacco smoking prevalence in Eastern Mediterranean countries.

BACKGROUND AND OBJECTIVES: This study aimed to assess the association between the 10-year implementation of tobacco control policies, cigarette affordability index and changes in tobacco smoking prevalence across Eastern Mediterranean (EMR) countries. MATERIALS AND METHODS: An ecologic study was conducted using EMR countries as the analytical unit. Data from three sources were utilized: the MPOWER scale to measure tobacco control policy implementation (2010-2020), the tobacco affordability index (expressed as a percentage of GDP per capita required to purchase 2000 cigarettes, from 2010 to 2020), and national tobacco smoking prevalence data for EMR countries (2010-2023). Linear Fixed-effect regression was employed to investigate associations between changes in MPOWER scores, the cigarette affordability index, and alterations in tobacco prevalence over a decade. RESULTS: Statistically significant inverse associations were observed between changes in MPOWER scores and tobacco smoking prevalence among both men and women in EMR countries (P-value<0.05). Each unit increase in MPOWER score corresponded to a 0.26% reduction in tobacco prevalence among men and a 0.12% reduction among women. The regression model revealed that each unit increase in the cigarette affordability index was linked to a 0.9% decrease in tobacco smoking prevalence across EMR countries (P-value<0.05). Furthermore, even after adjusting for multiple confounders, significant inverse associations were noted between tobacco monitoring (ß = -0.41), health warning (ß = -0.45), and changes in tobacco smoking prevalence (P-value<0.05). CONCLUSION: This study underscored the effectiveness of enhancing the implementation of tobacco control policies and increasing the cigarette affordability index as preventive measures to reduce tobacco smoking prevalence in EMR countries over the past decade.

A comparative study of tobacco control scale score in the Eastern Mediterranean Region countries.

Background: The tobacco control scale (TCS) score is used widely in European countries to evaluate the adoption of anti-tobacco policies by countries, however, data on the adoption of tobacco control programmes in the Eastern Mediterranean Region (EMR) are limited to a 2009 survey. Aim: To compare the TCS score for measuring national tobacco control programmes in the EMR countries in 2009 and 2021. Methods: This cross-sectional survey compared data from 21 EMR countries on 6 major indicators, including the price of cigarettes, tobacco smoke-free public places, national budget for tobacco control activities, ban on tobacco advertising, health warning labels on tobacco packets, and support for treatment of tobacco dependence. The TCS scores at the country level in 2009 were extracted from a previous study. We then calculated the TCS score in 2021 for the same countries using the WHO report on the global tobacco epidemic 2021 and the World Bank data for 2020. Results: The average TCS score (standard deviation) for EMR countries increased from 29.7 (16.8) in 2009 to 40.7 (17.3) in 2021. The highest TCS score (83.0) was reported in Islamic Republic of Iran, followed by Yemen (72.8) and Lebanon (62.0). Five countries (Djibouti, Syrian Arab Republic, Tunisia, Bahrain, and Oman) scored less than 30. Health warning labels, smoke-free public places, and tobacco control budgets as a percentage of Gross Domestic Product per capita had all increased, but tobacco prices and cessation treatments did not improve over the past decade. Conclusion: Tobacco control policies have been implemented and improved in most EMR countries, but there is room for further improvement. Tobacco pricing and taxation, national tobacco control program budgets, and cessation treatments require more attention.