982 resultados para Fís Adomnáin


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Se pretende definir el tipo de clara mas conveniente en las masas de latizal de Pinus nigra Arn. subsp. laricio (Poir) del Pais Vasco, a partir de la caracterizacion obtenida a traves de ciertos atributos individuales de los arboles y de su estratificacion vertical. Se desprende que los individuos no ofrecen rasgos distintivos destacables y suficientes sobre los que sustentar los criterios de eleccion de los arboles a apear en las claras, asi como que tampoco muestran tendencia hacia la estratificacion vertical. Desde este analisis, se apunta como necesario primar aspectos de sencillez y operatividad practica en la fase de senalamiento de la intervencion selvicola, optandose, en consecuencia, por las claras por lo bajo y posponiendose para mas adelante las selectivas.

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O objetivo do presente trabalho foi correlacionar a atividade da redutase do nitrato e a eficiência fotoquímica máxima do fotossistema II (FSII), expressa pela razão F V/F M (F V = fluorescência variável e F M = fluorescência máxima), em mamoeiro (Carica papaya L.) cv. Tainung 01 e Sunrise Solo 72/12 em condições de campo. O potencial fotoquímico do FSII foi medido in situ em folhas adaptadas ao escuro. Depois, nas mesmas folhas, foi medida a atividade da enzima. Não houve diferença significativa entre a eficiência fotoquímica máxima do FSII entre as cultivares Tainung 01 e Sunrise Solo 72/12, porém a atividade da redutase do nitrato foi notoriamente maior na primeira. A atividade da redutase do nitrato foi altamente correlacionada à eficiência fotoquímica máxima do FS II tanto na cv. Tainung 01 (coeficiente de correlação r= 0,740 e coeficiente de determinação r²= 0,706) quanto na Sunrise Solo 72/12 (coeficiente de correlação r= 0,960 e coeficiente de determinação r²= 0,945). Esses resultados sugerem que há uma correlação entre a fluorescência da clorofila a e a atividade da redutase do nitrato nessas plantas.

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OBJECTIVES: Many nanomaterials (materials with structures smaller than 100 nm) have chemical, physical and bioactive characteristics of interest for novel applications. Considerable research efforts have been launched in this field. This study aimed to study exposure scenarios commonly encountered in research settings. METHODS: We studied one of the leading Swiss universities and first identified all research units dealing with nanomaterials. After a preliminary evaluation of quantities and process types used, a detailed analysis was conducted in units where more than a few micrograms were used per week. RESULTS: In the investigated laboratories, background levels were usually low and in the range of a few thousand particles per cubic centimeter. Powder applications resulted in concentrations of 10,000 to 100,000 particles/cm(3) when measured inside fume hoods, but there were no or mostly minimal increases in the breathing zone of researchers. Mostly low exposures were observed for activities involving liquid applications. However, centrifugation and lyophilization of nanoparticle-containing solutions resulted in high particle number levels (up to 300,000 particles/cm(3)) in work spaces where researchers did not always wear respiratory protection. No significant increases were found for processes involving nanoparticles bound to surfaces, nor were they found in laboratories that were visualizing properties and structure of small amounts of nanomaterials. CONCLUSIONS: Research activities in modern laboratories equipped with control techniques were associated with minimal releases of nanomaterials into the working space. However, the focus should not only be on processes involving nanopowders but should also be on processes involving nanoparticle-containing liquids, especially if the work involves physical agitation, aerosolization or drying of the liquids.

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Aim of study: To identify species of wood samples based on common names and anatomical analyses of their transversal surfaces (without microscopic preparations). Area of study: Spain and South America Material and methods: The test was carried out on a batch of 15 lumber samples deposited in the Royal Botanical Garden in Madrid, from the expedition by Ruiz and Pavon (1777-1811). The first stage of the methodology is to search and to make a critical analysis of the databases which list common nomenclature along with scientific nomenclature. A geographic filter was then applied to the information resulting from the samples with a more restricted distribution. Finally an anatomical verification was carried out with a pocket microscope with a magnification of x40, equipped with a 50 micrometers resolution scale. Main results: The identification of the wood based exclusively on the common name is not useful due to the high number of alternative possibilities (14 for “naranjo”, 10 for “ébano”, etc.). The common name of one of the samples (“huachapelí mulato”) enabled the geographic origin of the samples to be accurately located to the shipyard area in Guayaquil (Ecuador). Given that Ruiz y Pavon did not travel to Ecuador, the specimens must have been obtained by Tafalla. It was possible to determine correctly 67% of the lumber samples from the batch. In 17% of the cases the methodology did not provide a reliable identification. Research highlights: It was possible to determine correctly 67% of the lumber samples from the batch and their geographic provenance. The identification of the wood based exclusively on the common name is not useful.

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ZnO nanorods grown by both high temperature vapour phase transport and low temperature chemical bath deposition are very promising sources for UV third harmonic generation. Material grown by both methods show comparable efficiencies, in both cases an order of magnitude higher than surface third harmonic generation at the quartz-air interface of a bare quartz substrate. This result is in stark contrast to the linear optical properties of ZnO nanorods grown by these two methods, which show vastly different PL efficiencies. The third harmonic generated signal is analysed using intensity dependent measurements and interferometric frequency resolved optical gating, allowing extraction of the laser pulse parameters. The comparable levels of efficiency of ZnO grown by these very different methods as sources for third harmonic UV generation provides a broad suite of possible growth methods to suit various substrates, coverage and scalability requirements. Potential application areas range from interferometric frequency resolved optical gating characterization of few cycle fs pulses to single cell UV irradiation for biophysical studies.

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This study evaluated the tolerance of mango cultivars 'Haden', 'Palmer', 'Tommy Atkins' and 'Uba' grafted on rootstock 'Imbú' to salt stress using chlorophyll fluorescence. Plants were grown in modified Hoagland solution containing 0, 15, 30, and 45 mmol L-1 NaCl. At 97 days the parameters of the chlorophyll fluorescence (F0, Fm, Fv, F0/Fm, Fv/Fm, Fv'/Fm', ΦPSII = [(Fm'-Fs)/(Fm')], D = (1- Fv'/Fm') and ETR = (ΦPSII×PPF×0,84×0,5) were determined. At 100 days, the leaf emission and leaf area, toxicity and leaf abscission indexes were determined. In all cultivars evaluated, in different degree, there were decreases in photochemical efficiency of photosystem II, enhanced concentrations from 15 mmol L-1 NaCl. The decreases in the potential quantum yield of photosystem II (Fv/Fm) were 27.9, 18.7, 20.5, and 27.4%, for cultivars 'Haden', 'Palmer', 'Tommy Atkins', and 'Uba', respectively, when grown in 45 mmol L-1 NaCl. It was found decreases in leaf emission and mean leaf area in all cultivars from 15 mmol L-1 NaCl. There were increases in leaf toxicity of 33.0, 67.5, 41.6 and 80.8% and in leaf abscission of 71.8, 29.2, 32.5, and 67.9% for the cultivars 'Haden', 'Palmer', 'Tommy Atkins', and 'Uba' respectively, when grown in 45 mmol L-1 NaCl. Leaf toxicity and leaf abscission were not observed in 15 mmol L-1 NaCl. The decrease in Fv/Fm ratio were accompanied by decreasing in leaf emission and increased leaf toxicity index, showing, therefore, the potential of chlorophyll fluorescence in the early detection of salt stress in mango tree.

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Whether or not to consolidate financial statements is dealt with in IPSAS#6. This standard is by and large based on IAS#27. It deals with the criterion according to which an entity's financial statements should be considered and which consolidation technique should be used. However, it remains silent when it comes to exposing the reason why a public sector entity should consolidate its financial statements. The literature is almost as silent as IPSAS on this issue. Which means that there is a lack of both theoretical and empirical knowledge on this subject. This paper explores the usefulness of the consolidation of financial statements (CFS) for different categories of users. It aims at investigating for which purposes consolidation is most useful and whether enlarging the scope of the consolidate group serves these purposes. Five purposes are considered: information, decision- making, accountability, risk-assessment, statistics improvement. The paper also aims at investigating if some categories of users consider CFS more useful than others. The issue is essentially empirical. Therefore it is examined in light of the results of an in-person interviews. We surveyed 25members of parliament, officials, creditors, and consultants of the Swiss central government. The results show that consolidating FS is considered especially important and useful for risk- assessment, information and accountability and to a somewhat lesser extent for decision-making and statistics improvement. Extending the scope of CFS may improve the situation when it comes to statistics but it would only marginally make CFS more relevant for decision making. Consultants and, to a lesser extent, members of the finance ministry are those respondents who deem the scope enlargement to be the most useful.

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Dioxins and furans, PCDD/Fs, are highly toxic substances formed in post combustion zones in furnaces. PCDD/F emissions are regulated by a waste incineration directive which relates also to co-incineration plants. Several observations of dioxin and furan enhancements in wet scrub- bers have been reported previously. This is thought to be due to the so-called "memory effect" which occurs when dioxins and furans absorb into plastic material in scrubbers and desorb when ambient circumstances alter significantly. At the co-incineration plant involved, dioxins and furans are controlled with a wet scrubber, the tower packing of which is made of plastic in which activated carbon particles are dispersed. This should avoid the memory effect and act as a dioxin and furan sink since dioxins and furans are absorbed irreversibly into the packing ma- terial. In this case, the tower packing in the scrubber is covered with a white layer that has been found to be mainly aluminium. The aim of this thesis was to determine the aluminium balance and the dioxin and furan behaviour in the scrubber and, thus, the impacts that the foul- ing has on dioxin and furan removal. The source of aluminium, reasons for fouling and further actions to minimize its impacts on dioxin and furan removal were also to be discovered. Measurements in various media around the scrubber and in fuels were made and a profile analysis of PCDD/F and mass balance calculations were carried out. PCDD/F content de- creased in the scrubber. The reduced PCDD/F was not discharged into scrubbing water. The removal mechanism seems to work in spite of the fouling, at least with low PCDD/F loads. Most of the PCDD/F in excess water originates from the Kymijoki River which is used as feeding water in the scrubber. Fouling turned out to consist mainly of aluminium hydroxides. Sludge combusted in the furnace was found to be a significant source of aluminium. Ways to minimize the fouling would be adjustment of pH to a proper lever, installation of a mechanical filter to catch the loose material from the scrubbing water and affecting the aluminium content of the sludge.

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A search for charmless three-body decays of B 0 and B0s mesons with a K0S meson in the final state is performed using the pp collision data, corresponding to an integrated luminosity of 1.0 fb−1, collected at a centre-of-mass energy of 7 TeV recorded by the LHCb experiment. Branching fractions of the B0(s)→K0Sh+h′− decay modes (h (′) = π, K), relative to the well measured B0→K0Sπ+π− decay, are obtained. First observation of the decay modes B0s→K0SK±π∓ and B0s→K0Sπ+π− and confirmation of the decay B0→K0SK±π∓ are reported. The following relative branching fraction measurements or limits are obtained $ B(B0→K0SK±π∓)B(B0→K0Sπ+π−)=0.128±0.017(stat.)±0.009(syst.),B(B0→K0SK+K−)B(B0→K0Sπ+π−)=0.385±0.031(stat.)±0.023(syst.),B(B0s→K0Sπ+π−)B(B0→K0Sπ+π−)=0.29±0.06(stat.)±0.03(syst.)±0.02(fs/fd),B(B0s→K0SK±π∓)B(B0→K0Sπ+π−)=1.48±0.12(stat.)±0.08(syst.)±0.12(fs/fd)B(B0s→K0SK+K−)B(B0→K0Sπ+π−)∈[0.004;0.068]at90%CL.

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Objetivo: Evaluar el impacto de un protocolo de acogida destinado a familiares de pacientes en nuestra unidad de cuidados intensivos (UCI) sobre el nivel de satisfacción familiar, al alta del paciente. Métodos: Estudio prospectivo cuasi-experimental. Sujetos del estudio: cuidadores principales y pacientes ingresados >24 h en la UCI. Durante dos meses, el grupo control (n=50) recibió la información y la orientación usuales del personal médico y de enfermería. Durante los dos meses siguientes, al grupo intervención (n=65) se le aplicó un protocolo de acogida estructurado y multidisciplinar, proveído en las primeras 24 h tras el ingreso. A ambos grupos (n=115) se les ofreció la Encuesta de Satisfacción Familiar en la UCI (FS-ICU©) en castellano. Resultados: El índice de respuesta del grupo control fue del 90%, frente al 70,7% del grupo intervención. Un total de 87 encuestas se consideraron válidas (>70% de ítems contestados). Observamos que el nivel de satisfacción general (FS-Total), y los niveles de satisfacción con los cuidados (FS-Cuidados) y con la toma de decisiones (FS-TD), en nuestra UCI, parecen muy altos. La mayoría de las puntuaciones de los distintos ítems de la encuesta en ambos grupos (83,3% frente al 79,1%) superaron el 75% en la escala 0-100%. La comparación de niveles de satisfacción entre grupos no muestra diferencias estadísticamente significativas. Conclusiones: Este estudio no demostró que esta intervención haya contribuido a una mejora significativa de la calidad percibida por los familiares en nuestra UCI, medidos con la encuesta FS-ICU© en castellano. Sin embargo, destaca cuestiones metodológicas para considerar en futuros estudios sobre este tema.

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La incursión de nuevas disciplinas en la lingüística, tales como la sociología, el cognitivismo, la antropología, etc., han permitido encontrar diversos puntos de unión entre las investigaciones realizadas desde cada una de estas disciplinas. Ello resulta de gran interés para los estudios de variación y contacto de lenguas en los que, aparte de los factores lingüísticos tradicionales, intervienen significativamente otros de índole cognitiva, sociocultural y pragmático-discursiva.Partiendo de este marco teórico plural, y desde la perspectiva del contacto de lenguas, en las siguientes páginas se analizan las expresiones prospectivas del español. Concretamente, se pretende aseverar la hipótesis de la influencia del catalán sobre el español en la expresión formal del futuro,1 pues parece que en las zonas catalanohablantes la frecuencia de uso del futuro sintético (FS) y del futuro analítico (FA) para hablar de eventos venideros es opuesta al empleo que de estas mismas formas suele hacerse en el resto de zonas hispanohablantes.2 La idea parte del hecho de que, pese a que en catalán también alternan las dos estructuras —el FS y la perífrasis prospectiva «ANAR A+Infinitivo»—, el menor rendimiento de la perífrasis en catalán y, por tanto, su menor grado de gramaticalización, parece incidir en la frecuencia de uso de la perífrasis en español «IR A+Infinitivo».

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High-resolution mass spectrometry (HRMS) has been associated with qualitative and research analysis and QQQ-MS with quantitative and routine analysis. This view is now challenged and for this reason, we have evaluated the quantitative LC-MS performance of a new high-resolution mass spectrometer (HRMS), a Q-orbitrap-MS, and compared the results obtained with a recent triple-quadrupole MS (QQQ-MS). High-resolution full-scan (HR-FS) and MS/MS acquisitions have been tested with real plasma extracts or pure standards. Limits of detection, dynamic range, mass accuracy and false positive or false negative detections have been determined or investigated with protease inhibitors, tyrosine kinase inhibitors, steroids and metanephrines. Our quantitative results show that today's available HRMS are reliable and sensitive quantitative instruments and comparable to QQQ-MS quantitative performance. Taking into account their versatility, user-friendliness and robustness, we believe that HRMS should be seen more and more as key instruments in quantitative LC-MS analyses. In this scenario, most targeted LC-HRMS analyses should be performed by HR-FS recording virtually "all" ions. In addition to absolute quantifications, HR-FS will allow the relative quantifications of hundreds of metabolites in plasma revealing individual's metabolome and exposome. This phenotyping of known metabolites should promote HRMS in clinical environment. A few other LC-HRMS analyses should be performed in single-ion-monitoring or MS/MS mode when increased sensitivity and/or detection selectivity will be necessary.

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Aim of the study: Mycorrhizal fungi in Mediterranean forests play a key role in the complex process of recovery after wildfires. A broader understanding of an important pyrophytic species as Pinus pinaster and its fungal symbionts is thus necessary for forest restoration purposes. This study aims to assess the effects of ectomycorrhizal symbiosis on maritime pine seedlings and how fire severity affects fungal colonization ability. Area of study: Central Spain, in a Mediterranean region typically affected by wildfires dominated by Pinus pinaster, a species adapted to fire disturbance. Material and Methods: We studied P. pinaster root apexes from seedlings grown in soils collected one year after fire in undisturbed sites, sites moderately affected by fire and sites highly affected by fire. Natural ectomycorrhization was observed at the whole root system level as well as at two root vertical sections (0-10 cm and 10-20 cm). We also measured several morphometric traits ( tap root length, shoot length, dry biomass of shoots and root/shoot ratio), which were used to test the influence of fire severity and soil chemistry upon them. Main results: Ectomycorrhizal colonization in undisturbed soils for total and separated root vertical sections was higher than in soils that had been affected by fire to some degree. Inversely, seedling vegetative size increased according to fire severity. Research highlights: Fire severity affected soil properties and mycorrhizal colonization one year after occurrence, thus affecting plant development. These findings can contribute to a better knowledge of the factors mediating successful establishment of P. pinaster in Mediterranean forests after wildfires.

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Samlingen med signum HB Sv.diss finns vid huvudbiblioteket och innehåller svenska doktorsavhandlingar. Den lista över avhandlingar som fåtts i april 2008 med sökfunktionen Signum och söktermen HB Sv.diss. kommer att ändra då den retroaktiva inmatningen i Alma ur bibliotekets alfabetiska kortkatalog genomförts. Period Antalet titlar - 1899 10 1900-49 214 1950-59 293 1960-69 616 1970-79 2952 Listan antyder att det skulle finns väldigt få svenska avhandlingar före år 1900 vid akademibiblioteket, vilket inte är med verkligheten överensstämmande. Dels ingår en del äldre avhandlingar i övriga samlingar, dels finns det en ansenlig separat samling svenska doktorsavhandlingar från äldre tid som inte i detta skede är katalogiserade, men finns förprickade i ett exemplar av Catalogus disputationum in Academiis Scandinaviae et Finlandiae Lidenianus (Lidén-Marklin) Med sökfunktionen Avancerad sökning och söktermen diss kombinerad med Sveriges ISBN 91 fås alla svenska doktorsavhandlingar vid hela akademibiblioteket fr.o.m. 1980.

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Filosofisk litteratur vid hela akademibiblioteket från och med år 2000 fås vid sökning i Alma med funktionen ämnesordssökning och söktermen filosofi.