889 resultados para Plants, Protection of
Resumo:
Species belonging to the Culicoides complexes (Diptera, Ceratopogonidae), obsoletus and pulicaris, in Switzerland, are potential vectors of both bluetongue virus (BTV) and African horse sickness virus (AHSV). The epidemic of BTV in 2006 and 2007 in Europe has highlighted the risk of introduction and spread of vector-borne diseases in previously non-endemic areas. As a measure of prevention, as part of an integrated control programme in the event of an outbreak of African horse sickness (AHS), it is of utmost importance to prevent, or substantially reduce, contact between horses and Culicoides. The aim of the present study was to compare the effect of three protection systems, net, fan, repellent, or combinations thereof, with regard to their potential to reduce contact between horses and Culicoides. Three different equine housing systems, including individual boxes (BX), group housing systems (GR), and individual boxes with permanently accessible paddock (BP) were used. The efficacy of the protection systems were evaluated by comparing the total number counts of collected female Culicoides, of non-blood-fed and blood-fed Culicoides, respectively, with UV black light traps. The study was conducted over 3 summer months during 2012 and 2013 each and focused on the efficacy and practicality of the protection systems. The repellent was tested in 2012 only and not further investigated in 2013, as it showed no significant effect in reducing Culicoides collected in the light traps. Net protection system provided the best overall protection for the total number of female Culicoides, non-blood-fed and blood-fed Culicoides in all tested housing systems. The net, with a pore size of 0.1825 mm(2), reduced the total number of Culicoides collected in the housing systems BP, GR and BX by 98%, 85% and 67%, respectively. However, in the GR housing system, no significant difference between the effectiveness of the fan and the net were determined for any of the three Culicoides categories. The results of the present study demonstrated that horse owners can substantially reduce their horses' exposure to Culicoides, by using net protection in the housing systems BX, BP and GR. In GR housing systems, protection against Culicoides using a fan is also recommended.
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The presentation proposed here shall focus on international (and as far as possible some cases of national) legal protection of civilians and refugees between the first Hague Convention of 1899 and the Geneva Convention for the Protection of Refugees in 1951. An analysis of international legal texts as well as, if possible, some exemplary national constitutions will form the core of the presentation, which will try to find out, to what extent not only the civilian population remaining close to front-line fighting, but also under occupation was supposed to be protected by legal norms, but also to what extent the issue of forcing civilian to leave their homes became part of the international legal discourse as well as of international legal norms.
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The enzyme catalysing the reduction of adenosine 5′-phosphosulfate (AdoPS) to sulfite in higher plants, AdoPS reductase, is considered to be the key enzyme of assimilatory sulfate reduction. In order to address its reaction mechanism, the APR2 isoform of this enzyme from Arabidopsis thaliana was overexpressed in Escherichia coli and purified to homogeneity. Incubation of the enzyme with [35S]AdoPS at 4 °C resulted in radioactive labelling of the protein. Analysis of APR2 tryptic peptides revealed 35SO2–3 bound to Cys248, the only Cys conserved between AdoPS and prokaryotic phosphoadenosine 5′-phosphosulfate reductases. Consistent with this result, radioactivity could be released from the protein by incubation with thiols, inorganic sulfide and sulfite. The intermediate remained stable, however, after incubation with sulfate, oxidized glutathione or AdoPS. Because truncated APR2, missing the thioredoxin-like C-terminal part, could be labelled even at 37 °C, and because this intermediate was more stable than the complete protein, we conclude that the thioredoxin-like domain was required to release the bound SO2–3 from the intermediate. Taken together, these results demonstrate for the first time the binding of 35SO2–3 from [35S]AdoPS to AdoPS reductase and its subsequent release, and thus contribute to our understanding of the molecular mechanism of AdoPS reduction in plants.
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This paper offers a principal-agent model of feasible private contracting in mitigation and conservation banking aimed at the protection of natural habitat and bio-diversity of US wetlands and uplands. It is shown that while it is straightforward to design an incentive contract, such a contract may not achieve the federally mandated objective of no net loss of habitat. This is because the minimum payment required as an economic incentive to private agents may be greater than what they should receive for the habitat values that they actually created in the field. This possible problem is shown to derive from nonconvexity in the production possibility set between the biological value of land as natural habitat and in non-habitat uses such as in urban development. The paper concludes with a consideration of several institutional devises that may promote the convergence of private contracting and the attainment of no net loss. These include the payment of subsidies, greater accuracy in the identification of actual quality by the principal, and the use of several incentive alignment devises.
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The practice of dowry is often thought to be the root cause of the unequal treatment of women in India. For women without inheritance rights, however, dowry may function as their only source of protection. Using a nationwide dataset and exploiting a natural experimental situation, this study explores the effects of dowry on women's empowerment in India, a society where women do not have inheritance rights. In such a society, dowry seems to enhance women's status in the marital household. The effects reverse when women have equal inheritance rights as their brothers. Empirical analysis suggests that the outright ban on dowry that ignores the context may not necessarily benefit women.
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The HiPER project, phase 4a, is evolving. In this study we present the progress made in the field of neutronics and radiological protection for an integrated design of the facility. In the current model, we take into account the optical systems inside the target bay, as well as the remote handling requirements and related infrastructure, together with different shields. The last reference irradiation scenario, consisting of 20 MJ of neutron yields, 5 yields per burst, one burst every week and 30 years of expected lifetime is considered for this study. We have performed a characterization of the dose rates behavior in the facility, both during operation and between bursts. The dose rates are computed for workers, regarding to maintenance and handling, and also for optical systems, regarding to damage. Furthermore, we have performed a waste management assessment of all the components inside the target bay. Results indicate that remote maintenance is mandatory in some areas. The small beam penetrations in the shields are responsible for some high doses in some specific locations. With regards to optics, the residual doses are as high as prompt doses. It is found that the whole target bay may be fully managed as a waste in 30 years by recycling and/or clearance, with no need for burial.
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Analysis of the "European Charter on General Principles for Protection of the Environment and Sustainable Development" The Council of Europe Document CO-DBP (2003) 2
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Análisis de la atenuación del oleaje por un carguero funcionando como dique flotante y aplicación a dos casos de protección portuaria y costera. The effectiveness of a bulk carrier working as a detached floating breakwater to protect a stretch of coast and form salients or tombolos is assessed in this paper. Experiments were conducted in the Madrid CEDEX facilities in a 30 m long, 3 m wide, 1/150 scale flume. The bulk carrier ship is 205 m long, 29 m wide and 18 m in height with a draught of 13 m, and has been subjected to irregular waves with significant heights from 2 m to 4 m and peak periods from 6 s to 12 s at a depth of 15 m, all prototype dimensions. Three probes were placed between the wave paddle and the ship to record incident and reflected waves and four probes were placed between the ship and the coastline to measure the transmitted waves. Transmission, reflection and dissipation coefficients (Ct, Cr, Cd) were calculated to determine wave attenuation. Results show good shelter in the lee of the ship with values of Ct under 0.5 for peak periods from 6 s to 11 s. In addition, forces on the mooring chains were measured showing maximum values of about 2000 tons at a 10 speak period. Finally, two analytical models were used to determine the shoreline’s response to the ship’s protection and to assess the possible forming of salients or tombolos. According to the results, salients - but not tombolos - are formed in all tests.
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It is frequently stated that UV light would cause massive destruction of prebiotic organic compounds because of the absence of an ozone layer. The elevated UV flux of the early sun compounds this problem. This applies to organic compounds of both terrestrial and extraterrestrial origin. Attempts to deal with this problem generally involve atmospheric absorbers. We show here that prebiotic organic polymers as well as several inorganic compounds are sufficient to protect oceanic organic molecules from UV degradation. This aqueous protection is in addition to any atmospheric UV absorbers and should be a ubiquitous planetary phenomenon serving to increase the size of planetary habitable zones.
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Limitation of water loss and control of gas exchange is accomplished in plant leaves via stomatal guard cells. Stomata open in response to light when an increase in guard cell turgor is triggered by ions and water influx across the plasma membrane. Recent evidence demonstrating the existence of ATP-binding cassette proteins in plants led us to analyze the effect of compounds known for their ability to modulate ATP-sensitive potassium channels (K-ATP) in animal cells. By using epidermal strip bioassays and whole-cell patch-clamp experiments with Vicia faba guard cell protoplasts, we describe a pharmacological profile that is specific for the outward K+ channel and very similar to the one described for ATP-sensitive potassium channels in mammalian cells. Tolbutamide and glibenclamide induced stomatal opening in bioassays and in patch-clamp experiments, a specific inhibition of the outward K+ channel by these compounds was observed. Conversely, application of potassium channel openers such as cromakalim or RP49356 triggered stomatal closure. An apparent competition between sulfonylureas and potassium channel openers occurred in bioassays, and outward potassium currents, previously inhibited by glibenclamide, were partially recovered after application of cromakalim. By using an expressed sequence tag clone from an Arabidopsis thaliana homologue of the sulfonylurea receptor, a 7-kb transcript was detected by Northern blot analysis in guard cells and other tissues. Beside the molecular evidence recently obtained for the expression of ATP-binding cassette protein transcripts in plants, these results give pharmacological support to the presence of a sulfonylurea-receptor-like protein in the guard-cell plasma membrane tightly involved in the outward potassium channel regulation during stomatal movements.
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Our group recently demonstrated that autoimmune T cells directed against central nervous system-associated myelin antigens protect neurons from secondary degeneration. We further showed that the synthetic peptide copolymer 1 (Cop-1), known to suppress experimental autoimmune encephalomyelitis, can be safely substituted for the natural myelin antigen in both passive and active immunization for neuroprotection of the injured optic nerve. Here we attempted to determine whether similar immunizations are protective from retinal ganglion cell loss resulting from a direct biochemical insult caused, for example, by glutamate (a major mediator of degeneration in acute and chronic optic nerve insults) and in a rat model of ocular hypertension. Passive immunization with T cells reactive to myelin basic protein or active immunization with myelin oligodendrocyte glycoprotein-derived peptide, although neuroprotective after optic nerve injury, was ineffective against glutamate toxicity in mice and rats. In contrast, the number of surviving retinal ganglion cells per square millimeter in glutamate-injected retinas was significantly larger in mice immunized 10 days previously with Cop-1 emulsified in complete Freund's adjuvant than in mice injected with PBS in the same adjuvant (2,133 ± 270 and 1,329 ± 121, respectively, mean ± SEM; P < 0.02). A similar pattern was observed when mice were immunized on the day of glutamate injection (1,777 ± 101 compared with 1,414 ± 36; P < 0.05), but not when they were immunized 48 h later. These findings suggest that protection from glutamate toxicity requires reinforcement of the immune system by antigens that are different from those associated with myelin. The use of Cop-1 apparently circumvents this antigen specificity barrier. In the rat ocular hypertension model, which simulates glaucoma, immunization with Cop-1 significantly reduced the retinal ganglion cell loss from 27.8% ± 6.8% to 4.3% ± 1.6%, without affecting the intraocular pressure. This study may point the way to a therapy for glaucoma, a neurodegenerative disease of the optic nerve often associated with increased intraocular pressure, as well as for acute and chronic degenerative disorders in which glutamate is a prominent participant.