804 resultados para Secondary amines


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Aromatic amines are widely used industrial chemicals as their major sources in the environment include several chemical industry sectors such as oil refining, synthetic polymers, dyes, adhesives, rubbers, perfume, pharmaceuticals, pesticides and explosives. They result also from diesel exhaust, combustion of wood chips and rubber and tobacco smoke. Some types of aromatic amines are generated during cooking, special grilled meat and fish, as well. The intensive use and production of these compounds explains its occurrence in the environment such as in air, water and soil, thereby creating a potential for human exposure. Since aromatic amines are potential carcinogenic and toxic agents, they constitute an important class of environmental pollutants of enormous concern, which efficient removal is a crucial task for researchers, so several methods have been investigated and applied. In this chapter the types and general properties of aromatic amine compounds are reviewed. As aromatic amines are continuously entering the environment from various sources and have been designated as high priority pollutants, their presence in the environment must be monitored at concentration levels lower than 30 mg L1, compatible with the limits allowed by the regulations. Consequently, most relevant analytical methods to detect the aromatic amines composition in environmental matrices, and for monitoring their degradation, are essential and will be presented. Those include Spectroscopy, namely UV/visible and Fourier Transform Infrared Spectroscopy (FTIR); Chromatography, in particular Thin Layer (TLC), High Performance Liquid (HPLC) and Gas chromatography (GC); Capillary electrophoresis (CE); Mass spectrometry (MS) and combination of different methods including GC-MS, HPLC-MS and CE-MS. Choosing the best methods depend on their availability, costs, detection limit and sample concentration, which sometimes need to be concentrate or pretreated. However, combined methods may give more complete results based on the complementary information. The environmental impact, toxicity and carcinogenicity of many aromatic amines have been reported and are emphasized in this chapter too. Lately, the conventional aromatic amines degradation and the alternative biodegradation processes are highlighted. Parameters affecting biodegradation, role of different electron acceptors in aerobic and anaerobic biodegradation and kinetics are discussed. Conventional processes including extraction, adsorption onto activated carbon, chemical oxidation, advanced oxidation, electrochemical techniques and irradiation suffer from drawbacks including high costs, formation of hazardous by-products and low efficiency. Biological processes, taking advantage of the naturally processes occurring in environment, have been developed and tested, proved as an economic, energy efficient and environmentally feasible alternative. Aerobic biodegradation is one of the most promising techniques for aromatic amines remediation, but has the drawback of aromatic amines autooxidation once they are exposed to oxygen, instead of their degradation. Higher costs, especially due to power consumption for aeration, can also limit its application. Anaerobic degradation technology is the novel path for treatment of a wide variety of aromatic amines, including industrial wastewater, and will be discussed. However, some are difficult to degrade under anaerobic conditions and, thus, other electron acceptors such as nitrate, iron, sulphate, manganese and carbonate have, alternatively, been tested.

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OBJECTIVE: To assess the occurrence of late thromboembolism after surgical repair of chronic atrial fibrillation (AF) simultaneously with repair of mitral valve using the Cox-Maze procedure. METHODS: 69 patients underwent Cox 3 procedure, with no cryoablation simultaneously with mitral valvuloplasty or prosthesis. Mean age was 49.9±13.2 years. Mean follow-up was of 31.7±19 months. Types of lesion were as follows: 33 (48%) stenoses, 23 (33%) insufficiencies, and 13 (19%) double lesions. Procedures were: 64 (93%) valvuloplasties, 3 (4%) biological and 2 (3%) mechanical prosthesis placement. There were 9 (13%) patients with previous systemic embolism and 2 (3%) had left atrial thrombi. RESULTS: Early mortality was 7% and late 1%. 2 patients (3%) were reoperated for mitral placement. At last evaluation, 10 patients (15%), were in AF. The remaining 59 (85%) were either in sinus / atrial rythm (74%) or under pacing (12%). There were no occurrence of early or late, systemic or pulmonary embolism. Permanent anticoagulation was employed in 16 cases, 10 in regular rythm and 6 in AF. The remaining 47 (75%), 2 in AF and 45 in regular rythm, did not receive anticoagulants. CONCLUSIONS: These results are in accordance with others series, where the occurrence of embolism was rare after maze procedure. Permanent systemic anticoagulation seems to be unnecessary in those cases.

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El uso de microorganismos como inoculantes para incrementar la disponibilidad y toma de nutrientes por parte de los cultivos, es una nueva tecnología que ha dado buenos resultados, observándose un incremento en la emergencia, vigor, mayor desarrollo en la parte aérea y de raíces, registrándose aumentos considerables de los rendimientos en cultivos de interés comercial. Esto es debido a que los microorganismos PGPR (Plant Growth promoting rhizobacteria) sintetizan ciertas sustancias reguladoras del crecimiento como giberelinas, citoquininas y auxinas; las cuales estimulan la densidad y longitud de los pelos radicales, aumentando así la cantidad y longitud de las raíces de los vegetales. Así, se incrementa la capacidad de absorción de agua y nutrientes, haciendo que las plantas sean más vigorosas, productivas y tolerantes a condiciones climáticas adversas, como sequías o heladas. Otro factor benéfico es que ciertos microorganismos solubilizan nutrientes poco móviles en el suelo como el caso del fósforo, segundo nutriente, después del nitrógeno en importancia para el crecimiento de los cultivos. Estos microorganismos también tienen una función muy importante en el control natural de agentes patógenos, a través de la inducción del sistema de defensa en las plantas, aumentando su resistencia a enfermedades, a través de la producción de compuestos bacterianos como antibióticos y sideróforos. Los variados mecanismos mediante los cuales la acción PGPR se lleva a cabo no son plenamente conocidos y, por lo tanto, es necesario determinar con precisión su efecto particular en la biología de la planta beneficiada. Las plantas aromáticas y medicinales inoculadas con microorganismos (rizobacterias) registran un incremento en varios parámetros de crecimiento vegetal (peso fresco parte aérea, peso seco de raíz, número de hojas, etc) y en el rendimiento de aceite esencial (AE). El aumento de la síntesis, y la variación de los porcentajes relativos de los componentes principales de AE en plantas aromáticas, como efecto de la inoculación, podría considerarse como una respuesta defensiva de la planta frente a la colonización de microorganismos dado que varios AE poseen propiedades antimicrobianas. El incremento de estos metabolitos también se ha registrado como respuesta frente a la herbivoría. En el presente proyecto se propone dilucidar la existencia de una relación entre las defensas inducidas por rizobacterias con la producción de metabolitos secundarios en plantas aromaticas y medicinales. The use of microorganisms as inoculants to increase the availability and nutrient uptake by crops, is a new technology that has been successfully applied, with an increase in the emergence, vigor, greater development in the shoot and roots, recording significant increases in yields of crop with commercial interest. This is because microorganisms PGPR (Plant Growth Promoting rhizobacteria) synthesize certain growth regulating substances such as gibberellins, cytokinins and auxins, which stimulate the density and length of root hairs, increasing the number and length of roots. Thus, increase the capacity of absorbing water and nutrients, make the plants more vigorous, productive and tolerant to adverse climatic conditions such as drought or frost.Another beneficial factor is that some microorganisms solubilize nutrients mobile in the soil as the case of phosphorus, second nutrient after nitrogen important for plant growth. These organisms also have an important role in the natural control of pathogens through the induction of the plants defense system, increasing their resistance to disease through the production of compounds such as antibiotics and bacterial siderophores. The various mechanisms by which PGPR action takes place are not fully known and therefore it is necessary to accurately determine its particular effect on the biology of the specific plant benefit. Aromatic and medicinal plants inoculated with microorganisms (rhizobacteria) recorded an increase in several parameters of plant growth (shoot fresh weight, root dry weight, leaf number, etc) and essential oil yield (AE). The increase in the biosynthesis, and changes in the relative percentages of the main components of AE in aromatic plants inoculated with rizobacterias, could be regarded as a plant defense response against microbial colonization, since several AE have antimicrobial properties. The increase of these metabolites have also been recorded as a response to herbivory.

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Abordar la infancia desde el enfoque de derechos (ED) implica una lectura de los derechos de los cuales los niños, niñas y adolescentes (NNA) son titulares y de las acciones estatales que se implementan para viabilizar el ejercicio concreto de ellos. Esta perspectiva exige comprender los contenidos de las políticas púb,el grado de participación que se les asigna y los sentidos que ellas toman en términos de progresividad de los derechos. Los cambios de concepción de la infancia desde la Convención Internacional de los Derechos del Niño (CIDN) y los cambios legislativos interpelan al Estado y la sociedad a modificar la visión hegemónica. Nuestra hipótesis gira alrededor de las siguientes considerac.: se han producido algunas modificaciones en las políticas y acciones estatales, aún no se dan las transformaciones necesarias de las lógicas institucionales y de los operadores que estimulen la participación de NNA en el ámbito escolar. Esto se visualiza en la ausencia de análisis cuali de los contenidos de las acc. y la falta de ftes estadísticas específicas, que muestren la orientac.de los contenidos en los principios de la protecc.integral. Estos presupuestos plantean interrogantes que delimitan el problema de investigación: ¿cómo se construye y reconstruye el ejercicio de la ciudadanía a través de la participación de los NNA, en su paso por la escuela, y cuáles son las lógicas institucionales que habilitan u obstaculizan ese ejercicio? Y ¿cuáles son los recursos institucionales que permitan que los programas y acciones redunden en el ejercicio efectivo de los derechos?.Obj.gral: Describir, analizar e interpretar la progresividad en el ejercicio de los derechos de participación e informacióin que tienen los adolescentes en escuelas secundarias de la cd de Cba, durante 2005 / 2010, para promover espacios públicos de construcción de ciudadanía. Se analizarán tres escuelas de Córdoba, escuela pública provincial, púb. nacional y privada. Obj. Espec.: Analizar las prácticas participativas formales e informales en las escuelas seleccionadas.- Aplicar indicadores cuanti y cualitativos del “Sistema de Indicadores para los derechos de la Infancia” Describir y analizar los recursos materiales y humanos. Elaborar y proponer procedim. para la confec. de registros de datos estadísticos - Elaborar y proponer lineamientos para la elaborac.e implementac.de acciones. Diseñar herramientas de difusión sobre los ds de participación e información.Esta investigac. es de carácter descriptivo e interpretativo, analizará diferentes ftes de informac.con técnicas cuanti y cualitativas, durante período la promulgación de la Ley 26061/05 y la adhesión prov. 9396/07. Se tomarán del Sistema de Indicadores, el derecho a la educación, el tema transversal “Acceso a la información y participación”, y las categorías de análisis “Recepción del Derecho y Capacidades estatales”. Se trabajaran indicadores cuanti y señales de progreso (cualitativos): estructurales, proceso y resultados. Serán analizados los Programas implementados durante el período de estudio. Estrategias cuali observac. participante, entrevistas, grupos focales, talleres de sensibilización, etc .Otras ftes de info: doc. institucionales, registros, evaluac, contenidos de programas y campañas y de difusión, prensa escrita, legislaciones, etc. La info se analizará a través Programa Atlas Ti, y del análisis estadístico. Algunos resultados esperados: Evaluac.y ajuste del Sistema de indicadores, la sensibilizac. desde el EF de autorid. escol. para la formulac. de planes y programas para el monitoreo adecuado de los mismos y para la rendic. de ctas de su gestión. Estimular la participac. de NNA en la escuela. Realizac.de documental. Brindar herramientas al Edo para superv de la aplicación progresiva del ejercicio de los derechos de participación e información de NNA Promov la continua evaluac. de los programas y acc.desde el ED para estimular el reconoc. de la nec.de ajuste de la política. The issue of children from the rights focus implies a reading of the rights in which children and adolescents are the holders and the state actions that are implemented to enable the exercise of them. This perspective requires understanding the contents of the public policies, the participation level that is assigned, and the senses that they take in terms of rights progressivity of. The conception changes about children since the International Convention on the Rights of the Child and legislative changes challenge to the State and society to modify hegemony vision. Our hypothesis revolves around the following considerations: there have been some public policies and state actions changes, but they not turn out, yet, transformations in logical institutional and actors whose are encourages children participation in school. This could be reflects in the absence of qualitative analysis in the actions contents and the lack of sources specific statistics, that will be showing the control of the principal contents of integral protection. These, raise the questions that delimit our problem research: how is built citizenship exercise through children and adolescent’s participation in the school, and what are the institutional logical that empowers or turns difficult that exercise? And What are the institutional resources that make possible the effective exercise of the rights, through different programs and actions?. General Objective: To describe, analyze and interpret exercise progressivity participation and information rights that have the adolescents in secondary schools in Córdoba City during 2005 / 2010, in order to promote public spaces for the construction of citizenship. It will analyze three schools in Cordoba, provincial public school, national public school and private school. . Obj. Specifics: To analyze the formal and informal participative practices in the schools selected. - To apply quantitative and qualitative indicators of the “Indicators System for Infa

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Climate change is a crisis that is going to affect all of our lives in the future. Ireland is expected to have increased storms and rain throughout the country. This will affect our lives greatly unless we do something to change it. In an attempt to try and reduce the impacts of climate change, countries across the world met to address the problem. The meeting became known as the Kyoto Protocol. The Kyoto protocol set out objectives for each developed country to achieve with regards to carbon emissions to the same levels as 1990 levels. Due to the economy in Ireland being at a low point in 1990, Ireland was given a target of 13% carbon emissions above 1990 levels. In order to meet targets Ireland produced two energy papers, the green paper and the white paper. The green paper identified drivers for energy management and control; they were security of energy supply, economic competitiveness and environmental protection. The white paper produced targets in which we should aim to achieve to try and address the green papers drivers. Within the targets was the plan to reduce energy consumption in the public sector by 33% by 2020 through energy conservation measures. Schools are part of the public sector that has targets to reduce its energy consumption. To help to achieve targets in schools initiatives have been developed by the government for schools. Energy audits should be performed in order to identify areas where the schools can improve their current trends and show where they can invest in the future to save money and reduce the schools overall environmental footprint. Grants are available for the schools for insulation through the energy efficiency scheme and for renewable energy technologies through the ReHeat scheme. The promotion of energy efficient programs in schools can have a positive effect for students to have an understanding. The Display Energy Certificate is a legal document that can be used to understand how each school is performing from an energy perspective. It can help schools to understand why they need to change their current energy management structure. By improving the energy management of the schools they then improve the performance on the Display Energy Certificate. Schools should use these tools wisely and take advantage of the grants available which can in the short to long term help them to save money and reduce their carbon footprint.

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Magdeburg, Univ., Fak. für Verfahrens- und Systemtechnik, Diss., 2012

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v.34:no.6(1952)

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v.22:no.2(1936)

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ABSTRACT In forest ecosystems, numerous species of insectivorous birds use certain tree species as feeding and nesting substrates. Between 2009 and 2010, the use of different floristic components as feeding substrate by the Pygarrhichas albogularis King, 1831 was evaluated in a southern Chilean secondary native forest. From a total of 13 trees and bush species, six tree species were used by P. albogularis as a feeding substrate. Tree use was limited to intermediate heights (11-20 m) and, mainly, to the trunk (40% of observations) and secondary branches (26%). Pygarrhichas albogularis showed a disproportionated use of N. dombeyi and an important use of trees with a greater age structure (DBH 81-100 cm). Nothofagus dombeyi presented a significantly greater tree bark crevice depth than E. cordifolia. In turn, covariance between crevice depth and invertebrate supply in tree bark was positive and significant. We consider bark depth and invertebrate supply to be the proximate causes explaining P. albogularis disproportionated use of Nothofagus dombeyi.

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RESUMEN El aumento del CO2 atmosférico debido al cambio global y/o a las prácticas hortícolas promueve efectos directos sobre crecimiento vegetal y el desarrollo. Estas respuestas pueden ocurrir en ecosistemas naturales, pero también se pueden utilizar para aumentar la producción de algunas plantas y de algunos compuestos secundarios. El actual trabajo intenta estudiar los efectos del enriquecimiento atmosférico del CO2 bajo condiciones de invernadero en el crecimiento y la concentración y la composición de metabolitos secundarios de Taxus bacatta, Hypericum perforatum y Echinacea purpurea en condiciones ambientales mediterráneas. La fertilización del CO2 muestra perspectivas interesantes para la mejorara y aplicabilidad de técnicas hortícolas para aumentar productividad de plantas medicinales, a pesar de diferencias claras entre la especie. En general esta técnica promueve aumentos importantes y significativos en producción primaria y, en algunos casos, también en compuestos secundarios. Esto tiene una gran importancia hortícola porque la productividad a nivel de cosecha total aumenta, directamente porque se aumenta la concentración e indirectamente porque se aumenta la biomasa. SUMMARY The increase of atmospheric CO2 due to global change and/or horticultural practices promotes direct effects on plant growth and development. These responses may occur in natural ecosystems, but also can be used to increase the production of some plants and some secondary compounds. Present work tries to study the effects of atmospheric CO2 enrichment under greenhouse conditions on growth and in the concentration and composition of secondary metabolites of Taxus bacatta, Hypericum perforatum and Echinacea purpurea under Mediterranean environmental conditions. CO2 fertilization shows interesting perspectives to increase and improve horticultural techniques in order to increase plant medicinal productivity, in spite of clear differences among the species. In general this technique promotes important and significant increases in primary productivity and, in some cases, also in secondary compounds. This has a great horticultural relevance because the total productivity of this kind of products increase at crop level, directly because concentration is increased and /or indirectly because biomass is increased. RESUM L'augment del CO2 atmosfèric a causa del canvi global i/o a les pràctiques hortícoles promou efectes directes sobre creixement vegetal i el desenvolupament. Aquestes respostes poden ocórrer en ecosistemes naturals, però també es poden utilitzar per a augmentar la producció d'algunes plantes i d'alguns compostos secundaris. L'actual treball intenta estudiar els efectes de l'enriquiment atmosfèric del CO2 sota condicions d'hivernacle en el creixement i la concentració i la composició de metabòlits secundaris de Taxus bacatta, Hypericum perforatum i Echinacea purpurea en condicions ambientals mediterrànies. La fertilització del CO2 mostra perspectives interessants per a la millora i aplicabilitat de tècniques hortícoles per a augmentar productivitat de plantes medicinals, a pesar de diferències clares entre l'espècie. En general aquesta tècnica promou augments importants i significatius en producció primària i, en alguns casos, també en compostos secundaris. Això té una gran importància hortícola perquè la productivitat a nivell de collita total augmenta, directament perquè s'augmenta la concentració i indirectament perquè s'augmenta la biomassa.

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Potential risks of a secondary formation of polychlorinated dibenzodioxins/furans (PCDD/Fs) were assessed for two cordierite-based, wall-through diesel particulate filters (DPFs) for which soot combustion was either catalyzed with an iron- or a copper-based fuel additive. A heavy duty diesel engine was used as test platform, applying the eight-stage ISO 8178/4 C1 cycle. DPF applications neither affected the engine performance, nor did they increase NO, NO2, CO, and CO2 emissions. The latter is a metric for fuel consumption. THC emissions decreased by about 40% when deploying DPFs. PCDD/F emissions, with a focus on tetra- to octachlorinated congeners, were compared under standard and worst case conditions (enhanced chlorine uptake). The iron-catalyzed DPF neither increased PCDD/F emissions, nor did it change the congener pattern, even when traces of chlorine became available. In case of copper, PCDD/F emissions increased by up to 3 orders of magnitude from 22 to 200 to 12 700 pg I-TEQ/L with fuels of < 2, 14, and 110 microg/g chlorine, respectively. Mainly lower chlorinated DD/Fs were formed. Based on these substantial effects on PCDD/F emissions, the copper-catalyzed DPF system was not approved for workplace applications, whereas the iron system fulfilled all the specifications of the Swiss procedures for DPF approval (VERT).