Development of a Phytochemical-Based Lure for the Dried Bean Beetle Acanthoscelides obtectus Say (Coleoptera: Chrysomelidae)

The dried bean beetle, Acanthoscelides obtectus, is an economically important, worldwide pest of legume crops including dry beans, Phaseolus vulgaris. Assessment of A. obtectus infestation levels in pre-harvest field crops and post-harvest granaries is difficult to achieve because there is no effective monitoring tool for early detection so that interventions can be deployed as needed. Because A. obtectus is a generic pollen and nectar feeder, we adopted an electrophysiological (EAG) screening approach, using the antennae of female A. obtectus to identify physiologically active, volatile phytochemicals, which could then be investigated for their attractiveness to A. obtectus in laboratory behavioral assays and preliminary field tests. Of the 27 compounds tested in EAG screening, 5 compounds, i.e., methyl anthranilate, methyl eugenol, benzyl alcohol, (RS)-lavandulol, and 2-phenylethanol, elicited stronger EAG responses than the standard (1-phenylethanol). In 4-arm olfactometer bioassays, female A. obtectus preferred the olfactometer arm containing the odor of either methyl anthranilate or benzyl alcohol compared to the solvent control. In preliminary field tests using these 2 compounds as a binary mixture, at least 5 times as many beetles were caught on baited traps compared to non-baited traps. The field data also suggested that benzyl alcohol was primarily responsible for the field activity of the blend. We hypothesize that the attraction of A. obtectus to the combined benzyl alcohol/methyl anthranilate and the single benzyl alcohol baits is connected to the species` nectar- and pollen-feeding behaviour and not to its intraspecific communication. To our knowledge, this is the first evidence that A. obtectus behavior in the field can be modified by the deployment of plant-derived semiochemicals.

     

Knowledge base support for dynamic information system management

Enterprise activities are governed by regulations and laws that are multiple, heterogeneous and not always easy to understand. The arising and/or the modification of these regulations and laws can cause a significant impact in the business context, especially in terms of enterprise information systems adaptation. Currently, there are many methodological and technological tools that facilitate the application of regulations and procedures, but they are not integrated enough to ensure a complete problem management. Therefore, they are not sufficient to support organizations and companies in the management of their business processes. In this paper we propose a methodological and technological solution, able to model, manage, execute and monitor business processes of complex domains. The system allows both the design of an information system and its prototyping as a web application, by the extension of an appropriately selected Business Process Management suite. During both the design and the usage phases of the prototyped information system, it is possible to interface with a knowledge base that contains information about regulations and aspects that characterize the enterprise (organizational chart, tasks, etc.).     

Note: flowing ion population from a resonance cavity source

The experimental low energy plasma for hemispherical analyzers nominal testing thermal plasma facility of Dartmouth College uses a microwave plasma source which generates an ionosphere-like plasma through a two-step process. The plasma is initially generated inside a cylindrical, insulated, resonance cavity. This initial plasma must pass through a sheath in order to enter the main experimental region. This process imparts a significant flow velocity to the ions which has been neglected in previous analysis of this plasma source. We predict the flow energy of the ions to be between 12-15 eV depending on conservation laws and show agreement with experimental results.     

Discipline-based instruction to promote interdisciplinary design of wearable and pervasive computing products

This paper reports on a design experience for undergraduates in computer engineering, industrial design, and marketing that focuses on pervasive computing devices. Across a broad range of targeted application areas and user groups, many of the student designs have been wearable computers. Consequently, our course will be of interest to the wearable computing community, particularly in terms of our aim of bridging the gap between design and engineering. For the two most recent offerings of the course, we have utilized external observers and surveyed the students in order to validate the impact of aspects of our process and changes to it. This paper is based upon 5 years of experience and 2 years of analysis of our course, and it presents an overview of our process with both qualitative and quantitative results from these two most recent offerings.     

Effect of curing characteristics on residual stress generation in polymethyl methacrylate bone cements

Residual stresses resulting from the shrinkage of polymethyl methacrylate (PMMA) bone cement have been implicated in the formation of cracks in cement mantles following total hip arthroplasty. This study investigates whether two such cements, with differentiated solidification characteristics (i.e. working and setting times), display significant differences in their residual stress characteristics in an experiment designed to replicate the physical conditions of total hip arthroplasty. Experiments were performed using a representative femoral construct to measure and compare the temperatures and residual strains developed for standard PMMA cement mantles (CMW 1 Gentamicin) and slow curing cement mantles (SmartSet HV Gentamicin) during and following polymerization. These experimental results revealed no statistically significant difference (t-test, p > 0.05) for peak exotherm temperature and residual strain levels between the cements (measured after 3 h). The tailored polymerization characteristics of the slow-curing cement do not significantly affect residual stress generation, compared with the standard cement. It is often considered that residual stresses significantly relax following polymerization and before biomechanical loads are first applied during rehabilitation (up to 3 days later). This was examined for durations of 18 h to 3 days. Axial strains in the model femur and stem reduced by averages of 5.5 and 7.9 per cent respectively, while hoop strains in the stem exhibited larger reductions. An axisymmetric transient thermoelastic finite element model of the experiment was developed, allowing residual stresses to be predicted based on differential scanning calorimetry (DSC) measurements of the heat released throughout the exothermic curing reaction. The model predictions closely replicated the experimental measurements of both temperature and residual strain at 3 h, suggesting that residual strains can be fully accounted for by the thermal contraction mechanism associated with cooling after solidification.     

Oral medication delivery in impaired swallowing: thickening liquid medications for safe swallowing alters dissolution characteristics

Acetaminophen (paracetamol) is available in a wide range of oral formulations designed to meet the needs of the population across the age-spectrum, but for people with impaired swallowing, i.e. dysphagia, both solid and liquid medications can be difficult to swallow without modification. The effect of a commercial polysaccharide thickener, designed to be added to fluids to promote safe swallowing by dysphagic patients, on rheology and acetaminophen dissolution was tested using crushed immediate-release tablets in water, effervescent tablets in water, elixir and suspension. The inclusion of the thickener, comprised of xanthan gum and maltodextrin, had a considerable impact on dissolution; acetaminophen release from modified medications reached 12–50% in 30?min, which did not reflect the pharmacopeia specification for immediate release preparations. Flow curves reflect the high zero-shear viscosity and the apparent yield stress of the thickened products. The weak gel nature, in combination with high G' values compared to G'' (viscoelasticity) and high apparent yield stress, impact drug release. The restriction on drug release from these formulations is not influenced by the theoretical state of the drug (dissolved or dispersed), and the approach typically used in clinical practice (mixing crushed tablets into pre-prepared thickened fluid) cannot be improved by altering the order of incorporation or mixing method.