2,077 research outputs found

    Sampling Technique for Larvae of the Alfalfa Snout Beetle, \u3ci\u3eOtiorhynchus Ligustici\u3c/i\u3e (Coleoptera: Curculionidae)

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    This paper presents a sampling procedure for estimating larval populations of the alfalfa snout beetle, Otiorhynchus ligustici. The method is based on counts of the larvae taken in 16 x 16 cm quadrats of soil during early fall when the grubs are in their final two instars and feeding just below the crowns of the plant. Analysis of sampling variability showed that 200 quadrats per field are necessary to obtain adequate precision for intensive population studies but that 50 quadrats are sufficient for survey work. The pattern of counts was overdispersed but conformed to the negative binomial distribution

    Two \u3ci\u3eEntomophthora\u3c/i\u3e Species Associated with Disease Epizootics of the Alfalfa Weevil, \u3ci\u3eHypera Postica\u3c/i\u3e (Coleoptera: Curculionidae), in Ontario

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    Recent studies have shown that disease epizootics in Ontario populations of the alfalfa weevil, Hypera postica (Gyllenhal), are caused by a complex of two fungi

    The role of unions in addressing behavioural market failures

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    The traditional view of economists is that unions cause market failures, thereby reducing economic efficiency. Freeman and Medoff challenged this overly negative view, suggesting unions address market failures associated with the ‘public goods’ aspects of terms and conditions in the workplace for members and non-members alike. This paper builds upon their work by arguing workers’ collective voice via unions can also be used to address particular behavioural market failures associated with common defects in individual cognition. Specifically, this paper suggests how unions through membership, expert and organisational learning effects can help address four common behavioural market failures or cognitive mistakes, namely, short-termism, inattention to important but hidden attributes, unrealistic optimism, and poor probability estimation. In order to explore how the three effects help mitigate the four failures, the paper draws upon insights from behavioural economics. Finally, the paper discusses the factors which influence the extent of the application of the three effects

    A union default: a policy to raise union membership, promote the freedom to associate, protect the freedom not to associate and progress union representation

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    Workers are defaulted to being non-union in employment relationships across the world. A non-union default likely has substantial negative effects, consistent with the empirical literature reviewed, on union membership levels, because of switching costs, inertia, social norms, and loss aversion. A union default would likely have positive effects on union membership, and has the additional virtues of partially internalising the public goods externalities of unions, improving the freedom to associate (the right to join a union), and preserving the freedom not to associate (the right not to join a union). A union default would also strengthen the extent and effectiveness of union representation

    Note sur l’aire de distribution et l’importance du Dacnusa dryas, un parasite introduit au Québec pour lutter contre l’agromyze de la lyzerne (Agromyza frontella)

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    De 1978 à 1980, le Dacnusa dryas, un hyménoptère d'origine européenne parasitant les larves et les pupes de l'agromyze de la luzerne, Agromyza frontella, fut relâché successivement dans deux localités du Québec. Une étude détaillée de son aire de distribution effectuée en 1986 démontre que l'insecte s'est dispersé dans les douze régions agricoles du Québec. Suite à sa naturalisation, les populations d'agromyze ont diminué à des niveaux sous-économiques.Dacnusa dryas, a European larval-pupal parasitoid of the alfalfa blotch leafminer, Agromyza frontella, was successively released in two areas of Quebec from 1978 to 1980. A detailed survey in 1986 shows that it has become established in all 12 agricultural regions. Coincident with its successful colonization, populations of the host have declined to subeconomic levels

    Using the endowment effect to explain managerial resistance towards codetermination: implications for employment relations from the German case

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    This article provides an innovative defence of co-determination by way of exploring two of the most significant theorised objections to it from neo-liberal and libertarian perspectives, namely, the defence of the right to manage as freely chosen by employees and employers alike, and the right to manage being the most efficient, lowest transaction cost mode of employee governance. Instead, we focus upon management preference emanating from the endowment effect, and manifested in management style and ideology, as a more credible explanation for management’s support for its prerogative to manage. The endowment effect prompts both strong employer and manager objections to co-determination and weak employee willingness to seek it because humans place more value upon items currently in their possession than upon those they do not possess. We explore this argument by examining the experience of co-determination in Germany. The significance of our argument lies in identifying managerial preference as the key variable to be challenged and changed in order to pacify management opposition to co-determination through political, ideological and institutional means

    Mixing rates across the Gulf Stream, Part 2: Implications for nonlocal parameterization of vertical fluxes in the surface boundary layers

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    The turbulent kinetic energy (TKE) budget of the surface mixed layer is evaluated at wintertime stations occupied in the vicinity of the strong Gulf Stream (GS) jet. The nonlocal K-profile parameterization (KPP) of vertical fluxes is combined with observed hydrography and meteorology to diagnose TKE production. This KPP-based production is averaged over the surface mixed layer and compared with corresponding averages of observed TKE dissipation rate from microstructure measurements, under assumptions of a homogeneous steady-state balance for the layer-averaged TKE budget. The KPP-based TKE production estimates exceed the mean observed boundary layer dissipation rates at occupied stations by up to an order of magnitude. In cases with strong upper ocean shear, the boundary layer depths predicted by the bulk Richardson number criteria of KPP tend to be deeper than indicated by observed dissipation rates, and thereby including strong entrainment zone shear contributes excessively to the KPP-based diagnosis of TKE production. However, even after correcting this diagnosis of mixed layer depth, the layer-averaged production still exceeds observed dissipation rates. These results have several possible implications, including: (1) KPP tends to overestimate vertical momentum flux in cases with strong shear due to geostrophically balanced thermal wind, unbalanced submesoscale dynamics, or entrainment driven by mixed layer inertial oscillations; (2) a mean local TKE balance does not hold in baroclinic mixed layers due to radiation of inertial waves, divergence in horizontal TKE flux or an inverse cascade to larger scales; and (3) both the boundary layer depth and the remaining TKE budget discrepancies indicate the limited validity of mixed layer models in the simulation of submesoscale ocean phenomena

    Long-term follow-up of intratympanic methylprednisolone versus gentamicin in patients with unilateral Menière’s disease

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    Objectives: To determine whether long term (>48 months) symptomatic vertigo control is sustained in patients with Menie`re’s disease from a previous comparative trial of intratympanic methylprednisolone versus gentamicin, and if the two treatments remain nonsignificantly different at longterm follow-up. Study Design: Mail survey recording vertigo frequency in the previous one and six months, further intratympanic treatment received, and validated symptom questionnaires. Setting: Outpatient hospital clinic setting. Patients: Adult patients with definite unilateral refractory Menie`re’s disease, who previously received in tratympanic treatment in a comparative trial. Intervention: A survey of trial participants who received intratympanic gentamicin (40 mg/mL) or methylprednisolone (62.5 mg/mL). Outcome measures: Primary: number of vertigo attacks in the 6 months prior to receiving this survey compared with the 6 months before the first trial injection. Secondary: : Number of vertigo attacks over the previous 1 month; validated symptom questionnaire scores of tinnitus, dizziness, vertigo, aural fullness, and functional disability. Results: Average follow-up was 70.8 months (standard deviation 17.0) from the first treatment injection. Vertigo attacks in the 6 months prior to receiving the current survey reduced by 95% compared to baseline in both drug groups (intention-to-treat analysis, both p<0.001). No significant difference between drugs was found for the primary and secondary outcomes. Eight participants (methylprednisolone ¼ 5 and gentamicin ¼ 3) required further injections for relapse after completing the original trial. Conclusion: Intratympanic methylprednisolone treatment provides effective long-lasting relief of vertigo, without the known inner-ear toxicity associated with gentamicin. There are no significant differences between the two treatments at long term follow-up

    A Cellular Automata Model with Probability Infection and Spatial Dispersion

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    In this article, we have proposed an epidemic model by using probability cellular automata theory. The essential mathematical features are analyzed with the help of stability theory. We have given an alternative modelling approach for the spatiotemporal system which is more realistic and satisfactory from the practical point of view. A discrete and spatiotemporal approach are shown by using cellular automata theory. It is interesting to note that both size of the endemic equilibrium and density of the individual increase with the increasing of the neighborhood size and infection rate, but the infections decrease with the increasing of the recovery rate. The stability of the system around the positive interior equilibrium have been shown by using suitable Lyapunov function. Finally experimental data simulation for SARS disease in China and a brief discussion conclude the paper

    Syndromic surveillance to assess the potential public health impact of the Icelandic volcanic ash plume across the United Kingdom, April 2010

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    The Eyjafjallajökull volcano in Iceland erupted on 14 April 2010 emitting a volcanic ash plume that spread across the United Kingdom and mainland Europe. The Health Protection Agency and Health Protection Scotland used existing syndromic surveillance systems to monitor community health during the incident: there were no particularly unusual increases in any of the monitored conditions. This incident has again demonstrated the use of syndromic surveillance systems for monitoring community health in real time
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