Publications by authors named "Downer R"

A Skinner mercury vapor light trap was operated from 2001 through 2009 in a residential backyard to document biodiversity within the moth families Thyatiridae, Drepanidae, Geometridae, Mimallonidae, Apatelodidae, Lasiocampidae, Saturniidae, Sphingidae, Erebidae (including Lymantriinae and Arctiinae), Euteliidae, Nolidae, and Noctuidae. When making comparisons to older literature, we recalculated our results to conform to the older classification of the Noctuoidea. Moths were released after identification.

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Purpose: To identify inflammatory cytokines significantly elevated and independent of VEGF levels in the vitreous of proliferative diabetic retinopathy (PDR) patients that may serve as novel diagnostic factors or therapeutic targets.

Methods: Thirty-nine cytokines and chemokines were measured from the vitreous of 72 patients undergoing vitrectomy (29 controls and 43 PDR) via a magnetic bead-based immunoassay. Patient information, including sex, age, history of smoking, cancer diagnosis and treatment, and presence of diabetes and hypertension were also collected.

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Populations in previously glaciated regions are often genetically depauperate in comparison with populations at lower latitudes, due either to bottlenecks experienced in post-glacial colonization or to contemporary genetic drift in small, peripheral populations. Populations of the rare self-fertilizing North American orchid Isotria medeoloides are largest in the previously glaciated region near the northern range limit, allowing us to examine the role of historical versus contemporary processes in determining population genetic diversity and structure. If contemporary processes predominate, genetic diversity should increase with increasing census size.

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The effects of clay dose and mixing energy on the efficiency of vegetable oil sedimentation by clay are investigated. The sedimentation efficiency increased with increasing clay dose to a maximum of about 80% of added oil. The maximum sedimentation efficiency was achieved at a lower clay dose, and the sedimentation efficiency was greater for a given clay dose when the oil was present as a thick oil film rather than as a thinner film.

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The development of resistance to an insecticide under various types of application method has yet to be reported in the literature. Five fall armyworm Spodoptera armigera (JE Smith) colonies were reared in a chamber for ten generations before starting topical application bioassays. From each colony, 200-500 third-fourth-instar larvae were fed for 72 h on corn plants sprayed with cypermethrin or spinosad at minimum application rate (20 g ha(-1)) using a small droplet size nozzle XR8001VS (volume median diameter D(v0.

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Staphylococcus aureus is an important cause of infective endocarditis (IE) in patients without a history of prior heart valve damage. The ability to stimulate the activation of resting platelets and their subsequent aggregation is regarded as an important virulence factor of bacteria that cause IE. Clumping factor A is the dominant surface protein responsible for platelet activation by S.

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The ability of Staphylococcus aureus to adhere to components of the extracellular matrix is an important mechanism for colonization of host tissues during infection. We have previously shown that S. aureus binds elastin, a major component of the extracellular matrix.

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Article Synopsis
  • Three different sprayers were tested to see how well they retained and applied two pesticides (spinosad and azadirachtin) on a soybean plant canopy in a greenhouse setting.
  • Results were evaluated based on the pests treated, including thrips, mites, and aphids, and effectiveness was measured by their abundance on the plants.
  • The study highlighted that while all sprayers influenced the retention of the pesticides, only those using the manufacturer's recommended volumes significantly affected pest populations, indicating that application volume is crucial to treatment efficacy.
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The elastin-binding proteins EbpS of Staphylococcus aureus strains Cowan and 8325-4 were predicted from sequence analysis to comprise 486 residues. Specific antibodies were raised against an N-terminal domain (residues 1-267) and a C-terminal domain (residues 343-486) expressed as recombinant proteins in Escherichia coli. Western blotting of lysates of wild-type 8325-4 and Newman and the corresponding ebpS mutants showed that EbpS migrated with an apparent molecular mass of 83 kDa.

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A method of testing for elevated disease rates using smoothed estimates is introduced for counts aggregated to a specific administrative level. A test statistic is developed based on an approximation to the smoothed estimate from a penalized multinomial likelihood and an approximate critical value is derived. Empirical investigation reveals that smoothing can increase the ability to detect elevated rates.

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Objective: To test the interrater reliability of the Clinical Dementia Rating (CDR) in a multicenter clinical trial.

Design: Observational study.

Setting: Training session for a multicenter trial of milameline, a direct muscarinic agonist, in the treatment of Alzheimer's disease.

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Abstract Phytoplankton and bacterial biomass and productivities were investigated at four depths in the upper 500 m of the water column in the Gerlache Strait, Antarctica, during the prebloom period of early austral spring, from October 13 to November 4, 1995. The concentrations of all carbon pools were low, with the total particulate organic carbon (POC) concentration averaging 1.9 +/- 0.

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The occupational exposure resulting from the application of crop protection agents continues to be of great interest for the purposes of identifying hazards or determining safer chemical handling methods. The purpose of the present study was to identify the potential respirator exposure of a mixer/loader to chlorothalonil, with the mixing and loading operation as the only source of aerosols (particles <13 microm diameter). Three worst-case mixing/loading scenarios were simulated in the lab: (1) a spill of undiluted chlorothalonil formulation onto a dry, horizontal metal surface; (2) a spill of undiluted chlorothalonil formulation onto a rapidly rotating shaft; and (3) pouring undiluted chlorothalonil formulation into a container of water.

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The invertebrate immune system produces melanotic nodules in response to bacterial infections and this has previously been shown to be mediated by eicosanoids. Nodulation occurs in two phases: the first involves hemocyte degranulation and activation of the prophenoloxidase cascade; the second involves formation of a cellular capsule by attachment and spreading of hemocytes. We demonstrate that inhibitors of eicosanoid biosynthesis affect both of these phases of nodulation in Galleria mellonella.

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Most recent developments in the smoothing of disease incidence rates have involved empirical Bayes procedures. Through the introduction of an intersite distance penalty, the pooling of information by directly penalizing the maximum likelihood estimates is proposed. A distance type statistic tests a null hypothesis of homogeneity among the rates and is applied to gastric cancer incidence of Nova Scotia municipalities.

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Nonsedimentable lipid-protein particles have been isolated from intestinal tissue of the American cockroach, Periplaneta americana. Most of the particles were within the range 30-50 nm in diameter and appear to originate from larger structures. Lipid analysis of the particles showed them to be enriched in neutral lipid components relative to microsomal membranes.

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The kinetic and pharmacological properties of [3H]tyramine and [3H]octopamine binding to membrane preparations of locust (Locusta migratoria migratorioides) brain were studied to characterize the tyramine and octopamine receptors. [3H]Tyramine and [3H]octopamine bind specifically and reversibly to the locust brain membrane with equilibrium achieved after 20 min. The dissociation of [3H]tyramine is monophasic while that of the [3H]octopamine shows a biphasic tendency.

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Octopamine and 5-hydroxytryptamine (5-HT) were previously shown to affect phagocytosis in cockroach hemocytes through unidentified receptor-mediated events. In the present study, we examined the ability of 5-HT and octopamine to enhance inositol trisphosphate (IP3) production using hemocyte membranes of the American cockroach, Periplaneta americana. Octopamine enhanced IP3 production with a maximal peak at 100 nM.

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The characteristics of protein kinase C (EC 2.7.1.

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Tyramine occurs in the central nervous system (CNS) of the migratory locust, Locusta migratoria migratoides. The distribution of tyramine within the CNS does not parallel that of octopamine. Tyramine is synthesised from tyrosine in the presence of tyrosine decarboxylase.

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Phosphatidylinositol kinase (PI kinase) and phosphatidylinositol 4-phosphate kinase (PIP kinase) activities in an insect cell line (Md 66) were studied by measuring the incorporation of 32P from [gamma-32P] ATP into phosphatidylinositol 4-phosphate (PIP) and phosphatidylinositol 4,5-bisphosphate (PIP2) respectively. The apparent Km values of phosphatidylinositol kinase and phosphatidylinositol 4-phosphate kinase for ATP were 78.5 microM and 71.

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A field experiment to investigate the formation of nitrate as an airstream passes through a hill cap cloud has been performed at the UMIST field station on Great Dun Fell. It has been shown that the aerosol nitrate concentration increased by about 0.5 microg m(-3) as the airstream passed through the cloud during the night.

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The role of proctolin has been further investigated in the locust (Locusta migratoria) mandibular closer muscles. Radioactive calcium uptake measurements were made using protease-dissociated muscle cells. Both the phorbol ester, phorbol-12,13-dibutyrate, and proctolin produce tonic contractions which are associated with the influx of extracellular calcium.

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An octopamine-sensitive adenylate cyclase that is insensitive to stimulation by dopamine (DA) and 5-hydroxytryptamine (5-HT), was studied in a homogenized nerve cord preparation of the migratory locust, Locusta migratoria. The enzyme complex is similar to catecholamine-sensitive cyclases from mammals with respect to pH-optimum, requirement for Mg++ and GTP, and sensitivity to forskolin. The octopamine-mediated elevation of adenylate cyclase activity is antagonized by a variety of drugs with the following order of potency: mianserin greater than phentolamine greater than promethazine greater than gramine greater than cyproheptadine greater than cis-flupenthixol greater than chlorpromazine greater than metoclopramide.

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