672 research outputs found
Population studies on Phytophthora infestans on potatoes and tomatoes in southern Germany
Fifty-seven isolates of Phytophthora infestans from blighted potato foliage were collected in 1995 in southern Germany and analysed for mating type and sensitivity to metalaxyl. Fifty-six of them were characterised as A1 and one as A2 mating types. Resistance to metalaxyl was observed frequently: 53 isolates were resistant, three were partially sensitive, and one was sensitive. In a subsequent field study in 1999, 84 isolates collected from blighted potato and tomato foliage were analysed for mating type. Seventy-two were characterised as A1 and twelve as A2 mating types. The response of 76 isolates to metalaxyl and to propamocarb was tested. The majority (42) of the 76 isolates was classified as resistant to metalaxyl; 31 were partially sensitive and only three isolates were sensitive. The results with propamocarb were less discrete; 10 isolates were classified as resistant and three were clearly sensitive. AFLP fingerprinting was used to examine the genetic structure of the southern German P. infestans population collected in 1999 and indicated that the tested population can be sub-divided into a tomato group, a potato group and a mixed group containing isolates collected from both crops. The presence of Ia and IIa mitochondrial DNA haplotypes indicates that the German P. infestans isolates belong to the new pathogen population that has also been reported in neighbouring regions of Europe. The present study indicates that at the beginning of the season only a few genotypes were present, and the population became genetically more variable at the end of the growing season
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Small Business Administration Microloan Program
This report describes the Microloan program's eligibility standards and operating requirements for lenders and borrowers and examines the arguments presented by the program's critics and advocates. It also examines changes to the program authorized by P.L. 111-240, the Small Business Jobs Act of 2010
Chiral Symmetry Restoration in the Schwinger Model with Domain Wall Fermions
Domain Wall Fermions utilize an extra space time dimension to provide a
method for restoring the regularization induced chiral symmetry breaking in
lattice vector gauge theories even at finite lattice spacing. The breaking is
restored at an exponential rate as the size of the extra dimension increases.
Before this method can be used in dynamical simulations of lattice QCD, the
dependence of the restoration rate to the other parameters of the theory and,
in particular, the lattice spacing must be investigated. In this paper such an
investigation is carried out in the context of the two flavor lattice Schwinger
model.Comment: LaTeX, 37 pages including 18 figures. Added comments regarding power
law fitting in sect 7. Also, few changes were made to elucidate the content
in sect. 5.1 and 5.3. To appear in Phys. Rev.
The Effectiveness of Co-Determination Laws in Cooperative and Adversarial Employment Relations: When Does Regulation Have Bite?
The German Codetermination Law grants workers of establishments with 200 or more employees the right to have a works councillor who is fully exempted from his or her regular job duties while still paid a regular salary. This article analyses theoretically and empirically how this de jure right to exemption translates into de facto practice, and explicitly takes into account the nature of the employment relations participation regime. It is found that the right of exemption has no effect in cooperative employment relations because exemptions are granted even in the absence of legal rights, but does make a difference in adversarial relations when exemptions are only granted above the threshold where legal rights force employers to do so, i.e. legal rights do make a decisive difference in exactly those situations where the legislators’ intent would not be realized without the right to legal enforcemen
Modelling Sand Fly Lutzomyia longipalpis Attraction to Host Odour: Synthetic Sex-Aggregation Pheromone Dominates the Response.
Zoontic visceral leishmaniasis (ZVL) due to Leishmania infantum is a potentially fatal protozoan parasitic disease of humans and dogs. In the Americas, dogs are the reservoir and the sand fly, Lutzomyia longipalpis, the principal vector. A synthetic version of the male sand fly produced sex-aggregation pheromone attracts both female and male conspecifics to co-located insecticide, reducing both reservoir infection and vector abundance. However the effect of the synthetic pheromone on the vector's "choice" of host (human, animal reservoir, or dead-end host) for blood feeding in the presence of the pheromone is less well understood. In this study, we developed a modelling framework to allow us to predict the relative attractiveness of the synthetic pheromone and potential alterations in host choice. Our analysis indicates that the synthetic pheromone can attract 53% (95% CIs: 39%-86%) of host-seeking female Lu. longipalpis and thus it out-competes competing host odours. Importantly, the results suggest that the synthetic pheromone can lure vectors away from humans and dogs, such that when co-located with insecticide, it provides protection against transmission leading to human and canine ZVL
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Unfunded Mandates Reform Act: History, Impact, and Issues
This report examines debates over what constitutes an unfunded federal mandate and the implementation of the Unfunded Mandates Reform Act of 1995 (UMRA). It includes an overview of UMRA, its origins, and provisions; definitions for unfunded federal mandates; how UMRA relates to Congressional procedure (Title I) and to federal rulemaking (Title II); and concluding observations on the issues
Recommended from our members
Unfunded Mandates Reform Act: History, Impact, and Issues
This report examines debates over what constitutes an unfunded federal mandate and the implementation of the Unfunded Mandates Reform Act of 1995 (UMRA). It includes an overview of UMRA, its origins, and provisions; definitions for unfunded federal mandates; how UMRA relates to Congressional procedure (Title I) and to federal rulemaking (Title II); and concluding observations on the issues
Exact solution (by algebraic methods) of the lattice Schwinger model in the strong-coupling regime
Using the monomer--dimer representation of the lattice Schwinger model, with
Wilson fermions in the strong--coupling regime (), we
evaluate its partition function, , exactly on finite lattices. By studying
the zeroes of in the complex plane for a large number of
small lattices, we find the zeroes closest to the real axis for infinite
stripes in temporal direction and spatial extent and 3. We find evidence
for the existence of a critical value for the hopping parameter in the
thermodynamic limit on the real axis at about . By looking at the behaviour of quantities, such as the chiral
condensate, the chiral susceptibility and the third derivative of with
respect to , close to the critical point , we find some indications
for a continuous phase transition.Comment: 22 pages (6 figures
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