948 resultados para Parasitoids - Treatments
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The overall goal of the project is the study of effects of conservation treatments applied on stone material from archaeological sites, i n terms of superficial changes, effectiveness and durability. In this sense, one of the first premises is characterize the surface of the treated and untreated material in order to determine changes in physical and chemical properties.
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Petrophysical properties, such as porosity, permeability, density or anisotropy de-termine the alterability of stone surfaces from archaeological sites, and therefore, the future preservation of the material. Others, like superficial roughness or color, may point out changes due to alteration processes, natural or man-induced, for ex-ample, by conservation treatments. The application of conservation treatments may vary some of these properties forcing the stone surface to a re-adaptation to the new conditions, which could generate new processes of deterioration. In this study changes resulting from the application of consolidating and hydrophobic treatments on stone materials from the Roman Theatre (marble and granite) and the Mitreo’s House (mural painting and mosaics), both archaeological sites from Merida (Spain), are analyzed. The use of portable field devices allows us to perform analyses both on site and in la-boratory, comparing treated and untreated samples. Treatments consisted of syn-thetic resins, consolidating (such as tetraethoxysilane TEOS) and hydrophobic products. Results confirm that undesirable changes may occur, with consequences ranging from purely aesthetic variations to physical, chemical and mechanical damages. This also permits us to check limitations in the use of these techniques for the evaluation of conservation treatments.
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Different treatments (consolidation and water-repellent) were applied on samples of marble and granite from the Front stage of the Roman Theatre of Merida (Spain). The main goal is to study the effects of these treatments on archaeological stone material, by analyzing the surface changes. X-Ray Fluorescence and Laser-Induced Breakdown Spectroscopy techniques, as well as Nuclear Magnetic Resonance have been used in order to study changes in the surface properties of the material, comparing treated and untreated specimens. The results confirm that silicon (Si) marker tracking allows the detection of applied treatments, increasing the peak signal in treated specimens. Furthermore, it is also possible to prove changes both within the pore system of the materialand in the distribution of surface water, resulting from the application of these products
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The effects of solutions of malic or orthophosphoric acids (0.752 Eqg/kg of feed) and heat to protect proteins of sunflower meal (SFM) and spring pea (SP) against ruminal degradation were studied using particle transit, 15N infusion, in situ and electrophoretic techniques. Three wethers fitted with rumen and duodenum cannulae were successively fed three isoproteic diets including SFM and SP, untreated or treated with malic or orthophosphoric acids. Incubations of tested meals were only performed while feeding the respective diet. Estimates of the ruminally undegraded fraction (RU) and its intestinal digestibility of dry matter, organic matter (only for RU), crude protein and starch (only in SP) were obtained considering ruminal microbial contamination and particle comminution and outflow rates. When corrected for microbial contamination, estimates of RU and intestinal digestibility decreased in all tested fractions for both feeds. All RU estimates increased with the protective treatments, whereas intestinal digestibility-dry matter also increased in SFM. Low intestinal digestibility-crude protein values suggested the presence of antitrypsin factors in SP. Protective treatments of both feeds led to consistent increases in the intestinal digested fraction of dry matter and crude protein, being only numerically different for SP-starch (60.5% as average). However, treatments also reduced the organic matter fermentation, which may decrease ruminal microbial protein synthesis. Electrophoretic studies showed albumin disappearance in both SFM and SP, whereas changes in other RU proteins were more pronounced in SP than SFM.
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Objective: To evaluate the effectiveness of diets, drug treatment, and behavioural interventions on infantile colic in trials with crying or the presence of colic as the primary outcome measure.
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Objective: To evaluate an experimental heroin maintenance programme.
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Objective: To identify and synthesise the findings from all randomised controlled trials that have examined the effectiveness of treatments of patients who have deliberately harmed themselves.
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Cross-sectional positron emission tomography (PET) studies find that cognitively normal carriers of the apolipoprotein E (APOE) ɛ4 allele, a common Alzheimer's susceptibility gene, have abnormally low measurements of the cerebral metabolic rate for glucose (CMRgl) in the same regions as patients with Alzheimer's dementia. In this article, we characterize longitudinal CMRgl declines in cognitively normal ɛ4 heterozygotes, estimate the power of PET to test the efficacy of treatments to attenuate these declines in 2 years, and consider how this paradigm could be used to efficiently test the potential of candidate therapies for the prevention of Alzheimer's disease. We studied 10 cognitively normal ɛ4 heterozygotes and 15 ɛ4 noncarriers 50–63 years of age with a reported family history of Alzheimer's dementia before and after an interval of approximately 2 years. The ɛ4 heterozygotes had significant CMRgl declines in the vicinity of temporal, posterior cingulate, and prefrontal cortex, basal forebrain, parahippocampal gyrus, and thalamus, and these declines were significantly greater than those in the ɛ4 noncarriers. In testing candidate primary prevention therapies, we estimate that between 50 and 115 cognitively normal ɛ4 heterozygotes are needed per active and placebo treatment group to detect a 25% attenuation in these CMRgl declines with 80% power and P = 0.005 in 2 years. Assuming these CMRgl declines are related to the predisposition to Alzheimer's dementia, this study provides a paradigm for testing the potential of treatments to prevent the disorder without having to study thousands of research subjects or wait many years to determine whether or when treated individuals develop symptoms.
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Previously, we developed a rat model of persistent mitochondrial dysfunction based upon the chronic partial inhibition of the mitochondrial enzyme cytochrome oxidase (EC 1.9.3.1). Continuous systemic infusion of sodium azide at approximately 1 mg/kg per hr inhibited cytochrome oxidase activity and produced a spatial learning deficit. In other laboratories, glucocorticoids have been reported to exacerbate neuronal damage from various acute metabolic insults. Therefore, we tested the hypothesis that corticosterone, the primary glucocorticoid in the rat, would potentiate the sodium azide-induced learning deficit. To this end, we first identified nonimpairing doses of sodium azide (approximately 0.75 mg/kg per hr) and corticosterone (100-mg pellet, 3-week sustained-release). We now report that chronic co-administration of these individually nonimpairing treatments produced a severe learning deficit. Moreover, the low dose of corticosterone, which did not elevate serum corticosterone, acted synergistically with sodium azide to inhibit cytochrome oxidase activity. The latter result represents a previously unidentified effect of glucocorticoids that provides a candidate mechanism for glucocorticoid potentiation of neurotoxicity induced by metabolic insult. These results may have the clinical implication of expanding the definition of hypercortisolism in patient populations with compromised oxidative metabolism. Furthermore, they suggest that glucocorticoid treatment may contribute to pathology in disease or trauma conditions that involve metabolic insult.
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Tomatoes are among the most cultivated and used vegetables in the world. They are very succeptible to post harvest losses due to high perishability, therefore the use of postharvest treatments may contribute to conservation of this fruit, however the treatments might affect significantly physico-chemical, sensory and nutritional characteristics of tomatoes. Given the perishability of tomato and the economic importance of small tomato fruits, the purpose of the present study was to determine the effect of gamma radiation, carnauba coating and 1-MCP treatments on tomato fruit quality during storage. The study may be divided into two parts. In the first, mini tomatoes cv. Sweet Grape were harvested at breaker stage, divided into 4 grous and treated with gamma radiation (0.6 kGy), carnauba coating (1 L 1000 kg-1) and 1-MCP (500 nL L-1) and then stored at 25±2°C for 30 days with a control group of tomatoes. In the seconnd part, tomatoes harvested at light-red stage were submitted to the same treatments and storage period. Every 6 days tomatoes were evaluated for color modifications, fruit firmness, souble and total pectin (only for light-red tomatoes), mass loss, titratable acidity (TA), soluble solids (SS), SS/TA ratio, carotenoids profile, formation of lycopene isomers, total phenolic compounds, ascorbic acid and antioxidant capacity. For tomatoes harvested at breaker stage and submitted to the treatments the results showed mass loss was delaying mainly by carnauba wax, and to a lesser extend by 1-MCP. Fruit firmness were better retained for 1-MCP treated fruits and carnauba treatment showed a transient effect in preserving fruit firmness. SS/TA of tomatoes treated with gamma radiation and carnauba presented no differences from control values, and were lower with the application of 1-MCP. Color was negatively affected by 1-MCP and earlier changed (6th day) when gamma radiation was applied. In relation to bioactive compounds of tomatoes harvest at breaker stage, results indicated gamma radiation and 1-MCP decreased the final content of lycopene and produced more (Z)-isomers of lycopene. Gamma radiation also induced a decreased in ?-carotene and an increased in phenolic compounds by the end of storage period. 1-MCP treatment promoted a slow down increase in ascorbic acid content during storage. Antioxidant capacity of the hydrophilic fraction was not dramatically affected by treatments and the lipophilic fraction was lower, especially for 1-MCP fruits. In addition, contents of ?-carotene, lycopene, (Z)-isomers of lycopene, ascorbic acid and antioxidant capacity increased during the period of storage while contents of lutein and phenolic compounds tended to decrease. Regarding tomatoes harvest at light-red stage, the most effective treatments for delaying fruit firmness and mass loss was carnauba and 1-MCP, while gamma radiation was the treatment with higher mass loss and the less fruit firmness, which could be associated with the higher solubilization of pectins promoted by radiation treatment. Color (L* and Hue) was mainly affected by 1-MCP treatment which delayed color development, however, by the end of storage, the values were not different from the other treatments. SS/TA ratio was lower for fruits treated with 1-MCP and TA was not so dramatically affected by treatments. Furthermore, mini tomatoes harvested at light-red stage, demonstrated irradiation induced changes in the final content of lycopene, increasing it, and formed less (13Z)-lycopene, while 1-MCP and carnauba coating slow down the increase in lycopene and slown down the decrease of ascorbic acid and phenolic compounds. Antioxidant capacity of lipophilic fraction was not affected by treatments and the hydrophilic fraction was lower for irradiated fruits only on day 0 as well as phenolic compounds. In the other days, no differences among treatments were observed for hydrophilic antioxidant capacity. Considering the results, the best combination of SS and TA and fruit preservation for mini tomatoes harvest at breaker stage was promoted by carnauba coating, which seems to be the treatment that causes fewer changes in bioactive compounds of breaker tomatoes. However, when mini tomatoes were harvested at light-red stage, SS/TA ratio and color were better and, to preserve the quality of these fruits, besides carnauba coating, 1-MCP also could be indicated