Foraging behaviour of Helicoverpa armigera first instar larvae on crop plants of different developmental stages

Understanding how insect pests forage on their food plants can help optimize management strategies. Helicoverpa armigera (Hubner) (Lep., Noctuidae) is a major polyphagous pest of agricultural crops worldwide. The immature stages feed and forage on crops at all stages of plant development, damaging fruiting and non-fruiting structures, yet very little is known about the influence of host type or stage on the location and behaviour of larvae. Through semi-continuous observation, we evaluated the foraging (movement and feeding) behaviours of H. armigera first instar larvae as well as the proportion of time spent at key locations on mungbean [Vigna radiata (L.) Wilczek] and pigeon pea [Cajanus cajan (L.) Millspaugh] of differing developmental stages: seedling- and mature (flowering/pod fill)-stage plants. Both host type and age affected the behaviour of larvae. Larvae spent more time in the upper parts of mature plants than on seedlings and tended to stay at the top of mature plants if they moved there. This difference was greater in pigeon pea than in mungbean. The proportion of time allocated to feeding on different parts of a plant differed with host and age. More feeding occurred in the top of mature pigeon pea plants but did not differ between mature and seedling mungbean plants. The duration of key behaviours did not differ between plant ages in either crop type and was similar between hosts although resting bouts were substantially longer on mungbeans. Thus a polyphagous species such as H. armigera does not forage in equivalent ways on different hosts in the first instar stage.

Information literacy for the humanities researcher: A syllabus based on information habits research

This paper reviews the existing literature on the information behavior of researchers in the humanities, in order to develop a set of learning objectives which can be used in the planning of information literacy training programs for this group of library users.

Gender differentials in the evolution of cigarette smoking habits in a general European adult population from 1993-2003

Background: Describe the recent evolution of cigarette smoking habits by gender in Geneva, where incidence rates of lung cancer have been declining in men but increasing in women. Methods: Continuous cross-sectional surveillance of the general adult ( 35 - 74 yrs) population of Geneva, Switzerland for 11 years ( 1993 - 2003) using a locally-validated smoking questionnaire, yielding a representative random sample of 12,271 individuals ( 6,164 men, 6,107 women). Results: In both genders, prevalence of current cigarette smoking was stable over the 11-year period, at about one third of men and one quarter of women, even though smoking began at an earlier age in more recent years. Older men were more likely to be former smokers than older women. Younger men, but not women, tended to quit smoking at an earlier age. Conclusion: This continuous ( 1993 - 2003) risk factor surveillance system, unique in Europe, shows stable prevalence of smoking in both genders. However, sharp contrasts in age-specific prevalence of never and former smoking and of ages at smoking initiation indicate that smoking continues a long-term decline in men but has still not reached its peak in women.

Dietary habits are major determinants of the plasma antioxidant status in healthy elderly subjects

Previous studies indicate that regular consumption of a diet rich in fruits and vegetables is associated with a lower risk for age-related diseases. The aim of the present study was to evaluate whether the often-reported age-related decrease of plasma antioxidants in man depends on differences in dietary intake or on other age- and gender-related factors. In this observational case-control study, thirty-nine community-dwelling healthy subjects aged 65 years and older consuming high intakes of fruits and vegetables daily (HI) and forty-eight healthy subjects aged 65 and older consuming low intakes of fruit and vegetables daily (LI) were enrolled. Plasma levels of retinol, tocopherols, carotenoids and malondialdehyde (MDA) as well as content of protein carbonyls in Ig G were measured. Plasma levels of retinol, tocopherols and carotenoids were significantly higher in group HI than in group LI subjects independent of age and gender. MDA levels were inversely correlated with vitamin A and α-carotene. Protein carbonyls were inversely correlated with γ-tocopherol. In the elderly, a higher daily intake of fruits and vegetables is associated with an improved antioxidant status in comparison to subjects consuming diets poor in fruits and vegetables. Modification of nutritional habits among other lifestyle changes should be encouraged to lower prevalence of disease risk factors in later life. © The Authors 2005.

How habits, social ties, and economic switching barriers affect customer loyalty in contractual service settings

While existing literature acknowledges positive effects of satisfaction and economic switching barriers for building customer loyalty, studies analyzing interactions of these antecedents reveal mixed findings. Prior research does not consider, as antecedents of switching barriers, either habits or social ties that result from shared service-usage within a family or community. This paper contributes to the literature, first, by replicating the effects of satisfaction, economic switching barriers, and their interaction with customer loyalty and word-of-mouth of subscribers to a contractual service. Second, the study empirically tests the role of social ties as a social switching barrier. Third, the study introduces and tests the effects of habits as a precursor of economic and social switching barriers. Results reveal significant positive effects of satisfaction, economic switching barriers, and social ties on customer loyalty and word-of-mouth. Additionally, economic switching barriers and social ties interact significantly with satisfaction and habits act as a precursor of economic switching barriers and social ties.

Survey of habits and attitudes to retinoscopy by optometrists in the UK

This research suggests that although retinoscopy is considered to be an important part of the eye examination by the majority, it is being carried out less by optometrists working in multiple practices. This less frequent use of retinoscopy may be due to the greater use of non-optometric staff in prescreening and that the more 'difficult' patients (young children or adults with poor communication) may be more likely to attend independent practices or an eye clinic.

An information foraging theory based user study of an adaptive user interaction framework for content-based image retrieval

This paper presents the design and results of a task-based user study, based on Information Foraging Theory, on a novel user interaction framework - uInteract - for content-based image retrieval (CBIR). The framework includes a four-factor user interaction model and an interactive interface. The user study involves three focused evaluations, 12 simulated real life search tasks with different complexity levels, 12 comparative systems and 50 subjects. Information Foraging Theory is applied to the user study design and the quantitative data analysis. The systematic findings have not only shown how effective and easy to use the uInteract framework is, but also illustrate the value of Information Foraging Theory for interpreting user interaction with CBIR. © 2011 Springer-Verlag Berlin Heidelberg.

Applying Information Foraging Theory to understand user interaction with content-based image retrieval

The paper proposes an ISE (Information goal, Search strategy, Evaluation threshold) user classification model based on Information Foraging Theory for understanding user interaction with content-based image retrieval (CBIR). The proposed model is verified by a multiple linear regression analysis based on 50 users' interaction features collected from a task-based user study of interactive CBIR systems. To our best knowledge, this is the first principled user classification model in CBIR verified by a formal and systematic qualitative analysis of extensive user interaction data. Copyright 2010 ACM.