898 resultados para Plants, Effect of insecticides on
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An effect of drift is investigated on the segregation pattern in diffusion-limited aggregation (DLA) with two components (A and B species). The sticking probability PAB (=PBA) between the different species is introduced into the DLA model with drift, where the sticking probability PAA (=PBB) between the same species equals 1. By using computer simulation it is found that the drift has an important effect on not only the morphology but also the segregation pattern. Under the drift and the small sticking probability, a characteristic pattern appears where elongated clusters of A species and of B species are periodically dispersed. The period decreases with increasing drift. The periodic structure of the deposits is characterized by an autocorrelation function. The shape of the cluster consisting of only A species (or B species) shows a vertically elongated filamentlike structure. Each cluster becomes vertically longer with decreasing sticking probability PAB. The segregation pattern is distinctly different from that with no drift and a small sticking probability PAA. The effect of the concentration on the segregation pattern is also shown.
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Behavioral and nutritional effect of rutin (quercetin 3-O-rutinosídeo) on Anticarsia gemmatalis Hübner (Lep.: Noctuidae), a major soybean defoliator in Brazil, was evaluated from the third instar to pupation. Rutin is one of the flavonol glycosides identified in the leaves of the wild soybean PI 227687. Larval weight and amount of ingested food decreased as rutin concentration in the diet increase. An interactive effect between feeding time and diet (treatment) was observed on insect growth; when larvae fed on pure-diet, feeding time elongation resulted in heavier pupae. Differently, the weight of larvae fed on rutin-diet remained almost stable, in spite of eating for longer. A. gemmatalis growth was negatively influenced by rutin-diet not only by feeding deterrence but also by post-ingestive effect on insect growth, since after adjustment of pupal weight by the amount of ingested food (covariate), the effect of diet remained significant. Rutin negatively influenced A. gemmatalis growth as result of pre-ingestive effect, indicated by reduction in food consumption, and post-ingestive effect, indicated by lower conversion of ingested food into body mass and food assimilation.
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Little is known of the relations between psychosis, religion and suicide. One hundred and fifteen outpatients with schizophrenia or schizo-affective disorder and 30 inpatients without psychotic symptoms were studied using a semi-structured interview assessing religiousness/spirituality. Their past suicide attempts were examined. Additionally, they were asked about the role (protective or incentive) of religion in their decision to commit suicide. Forty-three percent of the patients with psychosis had previously attempted suicide. Religiousness was not associated with the rate of patients who attempted suicide. Twenty-five percent of all subjects acknowledged a protective role of religion, mostly through ethical condemnation of suicide and religious coping. One out of ten patients reported an incentive role of religion, not only due to negatively connotated issues but also to the hope for something better after death. There were no differences between groups (i.e. psychotic vs. non-psychotic patients). Religion may play a specific role in the decisions patients make about suicide, both in psychotic and non-psychotic patients. This role may be protective, a finding particularly important for patients with psychosis who are known to be at high risk of severe suicide attempts. Interventions aiming to lower the number of suicide attempts in patients with schizophrenia should take these data into account.
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The Iowa D.O.T. specifications do not require 100 percent of 50 blow Marshall density (generally 94%) for field compaction. However, stabilities are determined in the Laboratory on specimens compacted to 100 percent of Marshall density. The purpose of this study is to determine the stabilities of specimens compacted to various densities which are below 100 percent of the 50 blow Marshall density.
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Other states have elected not to adopt the 75 Blow Marshall Mix Design for their heavy traffic roads. Their reasons are that the 75 blow design cracks the larger aggregates. Therefore, a limited study was done during December, 1985, to try to determine what amount of cracking took place, and in what condition the cracks are in the mix.
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The purpose of this work was to develop and optimize a simple and suitable method to detect the potential inhibitory effect of drugs and medicines on alcohol dehydrogenase (ADH) activity in order to evaluate the possible interactions between medicines and alcohol metabolism. Commonly used medicines that are often involved in court litigations related with driving under the influence of alcohol were selected. Alprazolam, flunitrazepam and tramadol were tested as drugs with no known effect on ADH activity. Cimetidine, reported previously as having inhibitory effect on ADH, and 4-methylpyrazole (4-MP), a well known ADH inhibitor, were tested as positive controls. Apart from 4-MP, tramadol was identified as having the higher inhibitory effect with an IC50 of 44.7×10(-3)mM, followed by cimetidine (IC50 of 122.9×10(-3)mM). Alprazolam and flunitrazepam also reduced liver ADH activity but to a smaller extent (inhibition of 11.8±5.0% for alprazolam 1.0mM and 34.5±7.1% for flunitrazepam 0.04mM). Apart from cimetidine, this is the first report describing the inhibitory effect of these drugs on ethanol metabolism. The results also show the suitability of the method to screen for inhibitory effect of drugs on ethanol metabolism helping to identify drugs for which further study is justified.
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We simulate freely jointed chains to investigate how knotting affects the overall shapes of freely fluctuating circular polymeric chains. To characterize the shapes of knotted polygons, we construct enveloping ellipsoids that minimize volume while containing the entire polygon. The lengths of the three principal axes of the enveloping ellipsoids are used to define universal size and shape descriptors analogous to the squared radius of gyration and the inertial asphericity and prolateness. We observe that polymeric chains forming more complex knots are more spherical and also more prolate than chains forming less complex knots with the same number of edges. We compare the shape measures, determined by the enveloping ellipsoids, with those based on constructing inertial ellipsoids and explain the differences between these two measures of polymer shape.
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Selostus: Kalkituksen vaikutus piparmintun ja Sachalinin mintun satoon Pohjois-Suomessa
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[Abstract]
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Large numbers and functionally competent T cells are required to protect from diseases for which antibody-based vaccines have consistently failed (1), which is the case for many chronic viral infections and solid tumors. Therefore, therapeutic vaccines aim at the induction of strong antigen-specific T-cell responses. Novel adjuvants have considerably improved the capacity of synthetic vaccines to activate T cells, but more research is necessary to identify optimal compositions of potent vaccine formulations. Consequently, there is a great need to develop accurate methods for the efficient identification of antigen-specific T cells and the assessment of their functional characteristics directly ex vivo. In this regard, hundreds of clinical vaccination trials have been implemented during the last 15 years, and monitoring techniques become more and more standardized.