988 resultados para central depressant agent


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El proyecto que se presenta a continuación recoge la adaptación de una Central Térmica de carbón al cumplimiento de la DIRECTIVA 2010/75/UE DEL PARLAMENTO EUROPEO Y DEL CONSEJO de 24 de noviembre de 2010 sobre las emisiones industriales. La Central sobre la que se realiza el proyecto tiene un grupo térmico de carbón suscritico refrigerado por agua, con una potencia a plena carga de 350 MWe y de 190 MWe a mínimo técnico. Genera 1 090 t/h de vapor a 540 °C y 168 kg/cm2 funcionando a plena carga. Actualmente las emisiones de NOx son de 650 mg/m3, (condiciones normales, seco, 6 % O2). El objeto del proyecto es reducir estas emisiones a un valor máximo de 200 mg/m3 en las mismas condiciones. El proyecto analiza detalladamente las condiciones actuales de operación de la instalación en cuanto a combustible utilizado, horas de funcionamiento, condiciones climáticas y producción. Se analiza así mismo, todas las técnicas disponibles en mercado para la reducción del NOx, diferenciando entre medidas primarias (actúan sobre los efectos de formación) y secundarias (limpieza de gases). Las medidas primarias ya están implementadas en la central, por tanto, el proyecto plantea la reducción con medidas secundarias. De las medidas secundarias analizadas se ha seleccionado la instalación de un Reactor de Reducción Selectiva Catalítica (Reactor SCR). Tras un análisis de los diferentes reactores y catalizadores disponibles se ha seleccionado un reactor de configuración High-dust, una disposición de catalizador en 3 capas más 1, cuyos componentes están basados en óxidos metálicos (TiO2, V2O5, WO3) y estructura laminar. Se ha buscado la instalación del reactor para operar a una temperatura inferior a 450 °C. Como agente reductor se ha seleccionado NH3 a una dilución del 24,5 %. El proyecto recoge también el diseño de todo el sistema de almacenamiento, evaporación, dilución e inyección de amoniaco. El resultado del proyecto garantiza una concentración en los gases de salida por la chimenea inferior 180 mg/m3(n) de NOx. La reducción del NOx a los límites establecidos, tienen un coste por MWh neto generado para la central, trabajando 60 % a plena carga y 40 % a mínimo técnico y una amortización de 10 años, de 4,10 €/MWh. ABSTRACT The following project shows the compliance adjustment of a coal-fired power station to the 2010/75/EU Directive of the European Parliament and Council 24th November 2010 on industrial emissions. The project is based on a power station with a subcritical thermal coal unit, cooled with water, with a maximum power of 350 MWe and a technical minimum of 190 MWe. It produces 1 090 t/h of steam at 540 ° C and 168 kg/cm2 operating under full load. Currently, NOx emissions are 650 mg / m3 (normal conditions, dry, 6% O2). The project aims to reduce these emissions to a maximum value of 200 mg / m3 under the same conditions. The project analyses in detail the current operating conditions of the system in terms of fuel used, hours of operation, climatic conditions and production. In addition, it also analyses every available technique of NOx reduction on the market, distinguishing between primary (acting on the effects of formation) and secondary measures (gas cleaning). Primary measures are already implemented in the plant, thus proposing reduction with secondary measures. Among the secondary measures analyzed, it has been selected to install a Selective Catalytic Reduction Reactor (SCR Reactor). Having researched the different reactors and catalysts available, for the reactor has been selected High-dust configuration, an arrangement of catalyst in 3 layers plus 1, whose components are based on metal oxides (TiO2, V2O5, WO3) and laminar structure. The reactor has been sought facility to operate at a temperature below 450 ° C. NH3 diluted to 24,5 % has been selected as reducing agent. The project also includes the design of the entire storage system, evaporation, dilution and ammonia injection. The results of the project ensure a gas concentration in the lower chimney exit below 180 mg / m3(n) NOx. The reduction of NOx to the established limits has a cost per net MWh generated in the plant, working at 60% of full load and at 40% of technical minimum, with an amortization of 10 years, 4,10 € / MWh.

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Experimental autoimmune encephalomyelitis (EAE) is a T cell autoimmune disorder that is a widely used animal model for multiple sclerosis (MS) and, as in MS, clinical signs of EAE are associated with blood–brain barrier (BBB) disruption. SR 57746A, a nonpeptide drug without classical immunosuppressive properties, efficiently protected the BBB and impaired intrathecal IgG synthesis (two conventional markers of MS exacerbation) and consequently suppressed EAE clinical signs. This compound inhibited EAE-induced spinal cord mononuclear cell invasion and normalized tumor necrosis factor α and IFN-γ mRNA expression within the spinal cord. These data suggested that pharmacological intervention aimed at inhibiting proinflammatory cytokine expression within the central nervous system provided protection against BBB disruption, the first clinical sign of EAE and probably the key point of acute MS attacks. This finding could lead to the development of a new class of compounds for oral therapy of MS, as a supplement to immunosuppressive agents.

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A novel fungal metabolite, apicidin [cyclo(N-O-methyl-l-tryptophanyl-l-isoleucinyl-d-pipecolinyl-l-2-amino-8-oxodecanoyl)], that exhibits potent, broad spectrum antiprotozoal activity in vitro against Apicomplexan parasites has been identified. It is also orally and parenterally active in vivo against Plasmodium berghei malaria in mice. Many Apicomplexan parasites cause serious, life-threatening human and animal diseases, such as malaria, cryptosporidiosis, toxoplasmosis, and coccidiosis, and new therapeutic agents are urgently needed. Apicidin’s antiparasitic activity appears to be due to low nanomolar inhibition of Apicomplexan histone deacetylase (HDA), which induces hyperacetylation of histones in treated parasites. The acetylation–deacetylation of histones is a thought to play a central role in transcriptional control in eukaryotic cells. Other known HDA inhibitors were also evaluated and found to possess antiparasitic activity, suggesting that HDA is an attractive target for the development of novel antiparasitic agents.

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Mice devoid of PrPC (Prnpo/o) are resistant to scrapie and do not allow propagation of the infectious agent (prion). PrPC-expressing neuroectodermal tissue grafted into Prnpo/o brains but not the surrounding tissue consistently exhibits scrapie-specific pathology and allows prion replication after inoculation. Scrapie prions administered intraocularly into wild-type mice spread efficiently to the central nervous system within 16 weeks. To determine whether PrPC is required for scrapie spread, we inoculated prions intraocularly into Prnpo/o mice containing a PrP-overexpressing neurograft. Neither encephalopathy nor protease-resistant PrP (PrPSc) were detected in the grafts for up to 66 weeks. Because grafted PrP-expressing cells elicited an immune response that might have interfered with prion spread, we generated Prnpo/o mice immunotolerant to PrP and engrafted them with PrP-producing neuroectodermal tissue. Again, intraocular inoculation did not lead to disease in the PrP-producing graft. These results demonstrate that PrP is necessary for prion spread along neural pathways.

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Transmissible spongiform encephalopathies, or prion diseases, are fatal degenerative disorders of the central nervous system that affect humans and animals. Prions are nonconventional infectious agents whose replication depends on the host prion protein (PrP). Transmission of prions to cultured cells has proved to be a particularly difficult task, and with a few exceptions, their experimental propagation relies on inoculation to laboratory animals. Here, we report on the development of a permanent cell line supporting propagation of natural sheep scrapie. This model was obtained by stable expression of a tetracycline-regulatable ovine PrP gene in a rabbit epithelial cell line. After exposure to scrapie agent, cultures were repeatedly found to accumulate high levels of abnormal PrP (PrPres). Cell extracts induced a scrapie-like disease in transgenic mice overexpressing ovine PrP. These cultures remained healthy and stably infected upon subpassaging. Such data show that (i) cultivated cells from a nonneuronal origin can efficiently replicate prions; and (ii) species barrier can be crossed ex vivo through the expression of a relevant PrP gene. This approach led to the ex vivo propagation of a natural transmissible spongiform encephalopathy agent (i.e., without previous experimental adaptation to rodents) and might be applied to human or bovine prions.

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There is substantial scientific evidence to support the notion that bovine spongiform encephalopathy (BSE) has contaminated human beings, causing variant Creutzfeldt–Jakob disease (vCJD). This disease has raised concerns about the possibility of an iatrogenic secondary transmission to humans, because the biological properties of the primate-adapted BSE agent are unknown. We show that (i) BSE can be transmitted from primate to primate by intravenous route in 25 months, and (ii) an iatrogenic transmission of vCJD to humans could be readily recognized pathologically, whether it occurs by the central or peripheral route. Strain typing in mice demonstrates that the BSE agent adapts to macaques in the same way as it does to humans and confirms that the BSE agent is responsible for vCJD not only in the United Kingdom but also in France. The agent responsible for French iatrogenic growth hormone-linked CJD taken as a control is very different from vCJD but is similar to that found in one case of sporadic CJD and one sheep scrapie isolate. These data will be key in identifying the origin of human cases of prion disease, including accidental vCJD transmission, and could provide bases for vCJD risk assessment.

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Between 2003 and 2014 the European Union’s (EU) Border Management Programme in Central Asia was implemented by the United Nations Development Programme (UNDP). However, the latter’s implementing responsibilities have just come to an end, with the next phase of the programme to be implemented by an EU member state consortium. This paper seeks to explain why the EU chose the UNDP to implement the programme in the first place; why the programme was redelegated to the UNDP over successive phases; and why, in the end, the EU has opted for a member state consortium to implement the next phase of the programme. The paper will draw on two alternative accounts of delegation: the principal-agent approach and normative institutionalism. Ultimately, it will be argued that both the EU’s decision(s) to delegate (and redelegate) implementing responsibilities to the UNDP, and its subsequent decision to drop the organisation in favour of an EU member state consortium, were driven for the most part by a rationalist ‘logic of consequentiality’. At the same time, a potential secondary role of a normative institutionalist ‘logic of appropriateness’ – as a supplementary approach – will not be discounted.

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Although there is considerable evidence to support the hypothesis that the chytrid fungus Batrachochytrium dendrobatidis is the primary agent responsible for widespread declines in amphibian populations, particularly rainforest frog populations in Australia and Central America, I argue the case has not yet been made conclusively. Few specimens were collected at the time of population declines, so it may never be possible to conclusively determine their cause. It remains unclear whether the pathogen is novel where declines have occurred. Although it is not necessary that the infection be novel for it to be implicated in declines, if a preexisting pathogen has only recently caused extinctions, cofactors must be important. Whether the pattern of outbreaks represents a wave of extinctions is unclear, but if it does, the rate of spread in Australia is implausibly high for a waterborne pathogen, given the most likely estimates of epidemiological parameters. Although B. dendrobatidis is an amphibian pathogen according to Koch's postulates, the postulates are neither necessary nor sufficient criteria to identify a pathogen. The following key pieces of information are necessary to better understand the impact of this fungus on frog communities: better knowledge of the means and rate of transmission under field conditions, prevalence of infection among frog populations, as distinct from morbid individuals, and the effect of the fungus on frogs in the wild. It is crucial to determine whether there are strains of the fungus with differing pathogenicity to particular frog species and whether host-pathogen coevolution has occurred or is occurring. Recently developed diagnostic tools bring into reach the possibility of addressing these questions and thus developing appropriate strategies to manage frog communities that may be affected by this fungus.

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The thrust of the argument presented in this chapter is that inter-municipal cooperation (IMC) in the United Kingdom reflects local government's constitutional position and its exposure to the exigencies of Westminster (elected central government) and Whitehall (centre of the professional civil service that services central government). For the most part councils are without general powers of competence and are restricted in what they can do by Parliament. This suggests that the capacity for locally driven IMC is restricted and operates principally within a framework constructed by central government's policy objectives and legislation and the political expediencies of the governing political party. In practice, however, recent examples of IMC demonstrate that the practices are more complex than this initial analysis suggests. Central government may exert top-down pressures and impose hierarchical directives, but there are important countervailing forces. Constitutional changes in Scotland and Wales have shifted the locus of central- local relations away from Westminster and Whitehall. In England, the seeding of English government regional offices in 1994 has evolved into an important structural arrangement that encourages councils to work together. Within the local government community there is now widespread acknowledgement that to achieve the ambitious targets set by central government, councils are, by necessity, bound to cooperate and work with other agencies. In recent years, the fragmentation of public service delivery has affected the scope of IMC. Elected local government in the UK is now only one piece of a complex jigsaw of agencies that provides services to the public; whether it is with non-elected bodies, such as health authorities, public protection authorities (police and fire), voluntary nonprofit organisations or for-profit bodies, councils are expected to cooperate widely with agencies in their localities. Indeed, for projects such as regeneration and community renewal, councils may act as the coordinating agency but the success of such projects is measured by collaboration and partnership working (Davies 2002). To place these developments in context, IMC is an example of how, in spite of the fragmentation of traditional forms of government, councils work with other public service agencies and other councils through the medium of interagency partnerships, collaboration between organisations and a mixed economy of service providers. Such an analysis suggests that, following changes to the system of local government, contemporary forms of IMC are less dependent on vertical arrangements (top-down direction from central government) as they are replaced by horizontal modes (expansion of networks and partnership arrangements). Evidence suggests, however that central government continues to steer local authorities through the agency of inspectorates and regulatory bodies, and through policy initiatives, such as local strategic partnerships and local area agreements (Kelly 2006), thus questioning whether, in the case of UK local government, the shift from hierarchy to network and market solutions is less differentiated and transformation less complete than some literature suggests. Vertical or horizontal pressures may promote IMC, yet similar drivers may deter collaboration between local authorities. An example of negative vertical pressure was central government's change of the systems of local taxation during the 1980s. The new taxation regime replaced a tax on property with a tax on individual residency. Although the community charge lasted only a few years, it was a highpoint of the then Conservative government policy that encouraged councils to compete with each other on the basis of the level of local taxation. In practice, however, the complexity of local government funding in the UK rendered worthless any meaningful ambition of councils competing with each other, especially as central government granting to local authorities is predicated (however imperfectly) on at least notional equalisation between those areas with lower tax yields and the more prosperous locations. Horizontal pressures comprise factors such as planning decisions. Over the last quarter century, councils have competed on the granting of permission to out-of-town retail and leisure complexes, now recognised as detrimental to neighbouring authorities because economic forces prevail and local, independent shops are unable to compete with multiple companies. These examples illustrate tensions at the core of the UK polity of whether IMC is feasible when competition between local authorities heightened by local differences reduces opportunities for collaboration. An alternative perspective on IMC is to explore whether specific purposes or functions promote or restrict it. Whether in the principle areas of local government responsibilities relating to social welfare, development and maintenance of the local infrastructure or environmental matters, there are examples of IMC. But opportunities have diminished considerably as councils lost responsibility for services provision as a result of privatisation and transfer of powers to new government agencies or to central government. Over the last twenty years councils have lost their role in the provision of further-or higher-education, public transport and water/sewage. Councils have commissioning power but only a limited presence in providing housing needs, social care and waste management. In other words, as a result of central government policy, there are, in practice, currently far fewer opportunities for councils to cooperate. Since 1997, the New Labour government has promoted IMC through vertical drivers and the development; the operation of these policy initiatives is discussed following the framework of the editors. Current examples of IMC are notable for being driven by higher tiers of government, working with subordinate authorities in principal-agent relations. Collaboration between local authorities and intra-interand cross-sectoral partnerships are initiated by central government. In other words, IMC is shaped by hierarchical drivers from higher levels of government but, in practice, is locally varied and determined less by formula than by necessity and function. © 2007 Springer.

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This thesis challenges the consensual scholarly expectation of low EU impact in Central Asia. In particular, it claims that by focusing predominantly on narrow, micro-level factors, the prevailing theoretical perspectives risk overlooking less obvious aspects of the EU?s power, including structural aspects, and thus tend to underestimate the EU?s leverage in the region. Therefore, the thesis argues that a more structurally integrative and holistic approach is needed to understand the EU?s power in the region. In responding to this need, the thesis introduces a conceptual tool, which it terms „transnational power over? (TNPO). Inspired by debates in IPE, in particular new realist and critical IPE perspectives, and combining these views with insights from neorealist, neo-institutionalist and constructivist approaches to EU external relations, the concept of TNPO is an analytically eclectic notion, which helps to assess the degree to which, in today?s globalised and interdependent world, the EU?s power over third countries derives from its control over a combination of material, institutional and ideational structures, making it difficult for the EU?s partners to resist the EU?s initiatives or to reject its offers. In order to trace and assess the mechanisms of EU impact across these three structures, the thesis constructs a toolbox, which centres on four analytical distinctions: (i) EU-driven versus domestically driven mechanisms, (ii) mechanisms based on rationalist logics of action versus mechanisms following constructivist logics of action, (iii) agent-based versus purely structural mechanisms of TNPO, and (iv) transnational and intergovernmental mechanisms of EU impact. Using qualitative research methodology, the thesis then applies the conceptual model to the case of EU-Central Asia. It finds that the EU?s power over Central Asia effectively derives from its control over a combination of material, institutional and ideational structures, including its position as a leader in trade and investment in the region, its (geo)strategic and security-related capabilities vis-à-vis Central Asia, as well as the relatively dense level of institutionalisation of its relations with the five countries and the positive image of the EU in Central Asia as a more neutral actor.

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Brain abscesses can cause an incapacitating neurological deicit in up to 50% of patients, thus the reduction of these sequelae becomes the main goal of its timely and speciic surgical and medical treatment. With technological advances in bacteriological identiication and diagnostic imaging, the clinical suspicion can be conirmed, and the speciic etiological agent can be identiied in a larger number of cases. New pathogens have emerged through this process, such as Streptococcus porcinus, in which the ability to affect the central nervous system has not been documented. A clinical case is presented of a brain abscess in an immunocompetent patient, and its favorable response to surgical drainage t hrough a skull burr h ole and nee dle aspiration with antibiotic therapy (ceftriaxone, metronidazole and vancomycin) is discussed.

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BACKGROUND: Midazolam is used for sedation before diagnostic and therapeutic medical procedures. It is an imidazole benzodiazepine that has depressant effects on the central nervous system (CNS) with rapid onset of action and few adverse effects. The drug can be administered by several routes including oral, intravenous, intranasal and intramuscular. OBJECTIVES: To determine the evidence on the effectiveness of midazolam for sedation when administered before a procedure (diagnostic or therapeutic). SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL to January 2016), MEDLINE in Ovid (1966 to January 2016) and Ovid EMBASE (1980 to January 2016). We imposed no language restrictions. SELECTION CRITERIA: Randomized controlled trials in which midazolam, administered to participants of any age, by any route, at any dose or any time before any procedure (apart from dental procedures), was compared with placebo or other medications including sedatives and analgesics. DATA COLLECTION AND ANALYSIS: Two authors extracted data and assessed risk of bias for each included study. We performed a separate analysis for each different drug comparison. MAIN RESULTS: We included 30 trials (2319 participants) of midazolam for gastrointestinal endoscopy (16 trials), bronchoscopy (3), diagnostic imaging (5), cardioversion (1), minor plastic surgery (1), lumbar puncture (1), suturing (2) and Kirschner wire removal (1). Comparisons were: intravenous diazepam (14), placebo (5) etomidate (1) fentanyl (1), flunitrazepam (1) and propofol (1); oral chloral hydrate (4), diazepam (2), diazepam and clonidine (1); ketamine (1) and placebo (3); and intranasal placebo (2). There was a high risk of bias due to inadequate reporting about randomization (75% of trials). Effect estimates were imprecise due to small sample sizes. None of the trials reported on allergic or anaphylactoid reactions. Intravenous midazolam versus diazepam (14 trials; 1069 participants)There was no difference in anxiety (risk ratio (RR) 0.80, 95% confidence interval (CI) 0.39 to 1.62; 175 participants; 2 trials) or discomfort/pain (RR 0.60, 95% CI 0.24 to 1.49; 415 participants; 5 trials; I² = 67%). Midazolam produced greater anterograde amnesia (RR 0.45; 95% CI 0.30 to 0.66; 587 participants; 9 trials; low-quality evidence). Intravenous midazolam versus placebo (5 trials; 493 participants)One trial reported that fewer participants who received midazolam were anxious (3/47 versus 15/35; low-quality evidence). There was no difference in discomfort/pain identified in a further trial (3/85 in midazolam group; 4/82 in placebo group; P = 0.876; very low-quality evidence). Oral midazolam versus chloral hydrate (4 trials; 268 participants)Midazolam increased the risk of incomplete procedures (RR 4.01; 95% CI 1.92 to 8.40; moderate-quality evidence). Oral midazolam versus placebo (3 trials; 176 participants)Midazolam reduced pain (midazolam mean 2.56 (standard deviation (SD) 0.49); placebo mean 4.62 (SD 1.49); P < 0.005) and anxiety (midazolam mean 1.52 (SD 0.3); placebo mean 3.97 (SD 0.44); P < 0.0001) in one trial with 99 participants. Two other trials did not find a difference in numerical rating of anxiety (mean 1.7 (SD 2.4) for 20 participants randomized to midazolam; mean 2.6 (SD 2.9) for 22 participants randomized to placebo; P = 0.216; mean Spielberger's Trait Anxiety Inventory score 47.56 (SD 11.68) in the midazolam group; mean 52.78 (SD 9.61) in placebo group; P > 0.05). Intranasal midazolam versus placebo (2 trials; 149 participants)Midazolam induced sedation (midazolam mean 3.15 (SD 0.36); placebo mean 2.56 (SD 0.64); P < 0.001) and reduced the numerical rating of anxiety in one trial with 54 participants (midazolam mean 17.3 (SD 18.58); placebo mean 49.3 (SD 29.46); P < 0.001). There was no difference in meta-analysis of results from both trials for risk of incomplete procedures (RR 0.14, 95% CI 0.02 to 1.12; downgraded to low-quality evidence). AUTHORS' CONCLUSIONS: We found no high-quality evidence to determine if midazolam, when administered as the sole sedative agent prior to a procedure, produces more or less effective sedation than placebo or other medications. There is low-quality evidence that intravenous midazolam reduced anxiety when compared with placebo. There is inconsistent evidence that oral midazolam decreased anxiety during procedures compared with placebo. Intranasal midazolam did not reduce the risk of incomplete procedures, although anxiolysis and sedation were observed. There is moderate-quality evidence suggesting that oral midazolam produces less effective sedation than chloral hydrate for completion of procedures for children undergoing non-invasive diagnostic procedures.