65 research outputs found

    Characterization of the pheromone communication channel in Mamestra configurata, the bertha armyworm

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    The bertha armyworm (BAW), Mamestra configurata, is one of the major insect pests feeding on a wide range of plant species, including canola, across western Canada. The components of the sex pheromone blend specific to M. configurata were identified in the 1970’s and are currently used in the pheromone trap monitoring system. However, there is evidence that geographic BAW populations develop at different rates and respond differently to the commercially prepared pheromone lures which affects our ability to accurately predict economic infestation levels for this pest. Collection of egg masses and pupae from several western Canada locations during the last BAW outbreak (2011-2014) presented a rare opportunity to investigate the genetics and biology of pheromone communication in M. configurata in field populations as compared to the long-term laboratory reared strain. My research encompassed aspects of both female pheromone production and male response to the female produced signal. I utilized next generation sequencing combined with bioinformatic analysis to identify and characterize genes involved in pheromone biosynthesis in females and chemosensory proteins involved in pheromone reception in males and females. I also used a novel single nucleotide polymorphism identification strategy to characterize genetic variation within pheromone specific chemosensory gene sequences among males from three BAW populations. The female pheromone gland analysis via gas chromatography coupled mass spectroscopy indicated that although, the amount of major and minor pheromone components varied greatly between individuals within a population, the pheromone blend ratios were not found to be significantly different between the two subpopulations investigated. Behavioural assays in the wind tunnel showed a marked difference in the ability of colony reared BAW males to take flight and reach the pheromone source as compared to field population males. Electrophysiological recordings obtained from colony and field population BAW male antenna showed significant loss of sensitivity to the minor pheromone component in the colony reared males. The knowledge gained from these studies will serve as a foundation for future research aimed at developing more effective integrated pest management strategies utilizing the pheromone communication channel for M. configurata

    Prisoners' attitudes towards cigarette smoking and smoking cessation: a questionnaire study in Poland

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    BACKGROUND: In the last decade Poland has successfully carried out effective anti-tobacco campaigns and introduced tobacco control legislation. This comprehensive strategy has focused on the general population and has led to a considerable decrease in tobacco consumption. Prisoners constitute a relatively small part of the entire Polish population and smoking habits in this group have been given little attention. The aim of the study was to assess the prevalence of cigarette smoking in Polish male prisoners, factors determining smoking in this group, prisoners' attitudes towards smoking cessation, and to evaluate prisoners' perception of different anti-tobacco measures. METHODS: An anonymous questionnaire including personal, demographic and smoking data was distributed among 944 male inmates. Of these, 907 men aged between 17 and 62 years (mean 32.3 years) met the inclusion criteria of the study. For the comparison of proportions, a chi-square test was used with continuity correction whenever appropriate. RESULTS: In the entire group, 81% of the subjects were smokers, 12% – ex-smokers, and 7% – never smokers. Current smokers had significantly lower education level than non-smokers (p < 0.0001) and ever-smokers more frequently abused other psychoactive substances than never smokers (p < 0.0001). Stress was reported as an important factor in prompting smoking (77%). Forty-nine percent of daily smokers were aware of the adverse health consequences of smoking. The majority of smokers (75%) had attempted to quit smoking in the past. Forty percent of smoking prisoners considered an award for abstaining from cigarettes as the best means to limit the prevalence of smoking in prisons. CONCLUSION: The prevalence of cigarette smoking among Polish prisoners is high. However, a majority of smokers attempt to quit, and they should be encouraged and supported. Efforts to reduce cigarette smoking in prisons need to take into consideration the specific factors influencing smoking habits in prisons

    Factors affecting commencement and cessation of smoking behaviour in Malaysian adults

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    <p>Abstract</p> <p>Background</p> <p>Tobacco consumption peak in developed countries has passed, however, it is on the increase in many developing countries. Apart from cigarettes, consumption of local hand-rolled cigarettes such as <it>bidi </it>and <it>rokok daun </it>are prevalent in specific communities. Although factors associated with smoking initiation and cessation has been investigated elsewhere, the only available data for Malaysia is on prevalence. This study aims to investigate factors associated with smoking initiation and cessation which is imperative in designing intervention programs.</p> <p>Methods</p> <p>Data were collected from 11,697 adults by trained recording clerks on sociodemographic characteristics, practice of other risk habit and details of smoking such as type, duration and frequency. Smoking commencement and cessation were analyzed using the Kaplan-Meier estimates and log-rank tests. Univariate and multivariate Cox proportional hazard regression models were used to calculate the hazard rate ratios.</p> <p>Results</p> <p>Males had a much higher prevalence of the habit (61.7%) as compared to females (5.8%). Cessation was found to be most common among the Chinese and those regularly consuming alcoholic beverages. Kaplan-Meier plot shows that although males are more likely to start smoking, females are found to be less likely to stop. History of betel quid chewing and alcohol consumption significantly increase the likelihood of commencement (p < 0.0001), while cessation was least likely among Indians, current quid chewers and kretek users (p < 0.01).</p> <p>Conclusions</p> <p>Gender, ethnicity, history of quid chewing and alcohol consumption have been found to be important factors in smoking commencement; while ethnicity, betel quid chewing and type of tobacco smoked influences cessation.</p

    The Dopamine Transporter Gene, a Spectrum of Most Common Risky Behaviors, and the Legal Status of the Behaviors

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    This study tests the specific hypothesis that the 9R/9R genotype in the VNTR of the dopamine transporter gene (DAT1) exerts a general protective effect against a spectrum of risky behaviors in comparison to the 10R/9R and 10R/10R genotypes, drawing on three-time repeated measures of risky behaviors in adolescence and young adulthood on about 822 non-Hispanic white males from the Add Health study. Our data have established two empirical findings. The first is a protective main effect in the DAT1 gene against risky behaviors. The second finding is that the protective effect varies over age, with the effect prominent at ages when a behavior is illegal and the effect largely vanished at ages when the behavior becomes legal or more socially tolerated. Both the protective main effect and the gene-lifecourse interaction effect are replicated across a spectrum of most common risky behaviors: delinquency, variety of sexual partners, binge drinking, drinking quantity, smoking quantity, smoking frequency, marijuana use, cocaine use, other illegal drug use, and seatbelt non-wearing. We also compared individuals with the protective genotype and individuals without it in terms of age, physical maturity, verbal IQ, GPA, received popularity, sent popularity, church attendance, two biological parents, and parental education. These comparisons indicate that the protective effect of DAT1*9R/9R cannot be explained away by these background characteristics. Our work demonstrates how legal/social contexts can enhance or reduce a genetic effect on risky behaviors

    The scope of soil investigation and selection of parameters, required for the preparation of numerical models of deep foundation - experiences and conclusions

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