971 resultados para Dry and rainy seasons
Resumo:
The Quaternary climate of southern Europe (south Italy and Greece) is investigated by pollen analysis of the sapropels which were deposited in the deep eastern Mediterranean Sea during the last 1 million year (Ma). The time-scale of core KC01b in the Ionian Sea has been established by tuning its oxygen isotopic record to the ice volume model of Imbrie and Imbrie (1980, doi:10.1126/science.207.4434.943). For the last 250,000 year (250 ka), the previous pollen studies and astronomical tuning have been confirmed. Sapropels were deposited under a large range of Mediterranean climates: fully interglacial, fully glacial, and intermediary, as revealed mainly by the balance between the respective pollen abundances of oak (Quercus) and sage-brush (Artemisia). The high value of the oak reveals the warm and wet climate of an Interglacial, and the high value of the sage-brush, the dry and cold climate of a Glacial. Whereas the Mediterranean climate is directly related to the variation of the high-latitude ice sheets, the deposition of sapropels is not so. In contrast with the wide climatic range, sapropels were deposited only when summer insolation in the low latitudes reached its highest peaks. However, between 250 ka and 1 Ma, that stable pattern is not yet established. Only six sapropels are observed, many expected ones do not appear, even as ghosts signalled by peaks of barium abundance, that remain after the post-deposition oxidation of organic matter. The pattern of sapropel formation in stable and direct relationship to highest insolation does not seem to apply. For five of those sapropels, neither climate extremes are observed; they mainly formed during intermediary types of Mediterranean climate. In contrast, one sapropel (and one ghost) relates to a relatively low peak of insolation, and its climate is of a unique, composite type not seen later. This might suggest an unsuspected, more complex pattern linking the formation of Mediterranean sapropels to the astronomical configuration.
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La serie Penny Dreadful (2014-presente) recupera personajes y tramas de novelas de terror y/o fantásticas ampliamente conocidas. La propuesta narrativa de esta serie creada por John Logan sitúa dichos elementos en la convulsionada Londres decimonónica y los fusiona, configurando así un discurso propio acerca de la "monstruosidad" de los personajes que presenta. En esta refundición, la serie ejercita una serie de reflexiones sobre la condición humana y la del monstruo. Como se plantea en la segunda temporada, al retomar el mito de Pandora y reformularlo, la distinción entre el hombre y el monstruo parece quedar en suspenso, dando lugar a una concepción de la monstruosidad diferente a la que encontramos en otras producciones televisivas contemporáneas. En este artículo analizamos las representaciones de la monstruosidad y las identidades en Penny Dreadful para ello prestaremos especial atención a los personajes y sus interacciones a lo largo de la primera y segunda temporada de la serie, así como a la relación entre la serie y sus fuentes literarias
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Previous research has reported both agreements and serious anomalies in relationships between production attributes of sugarcane varieties in variety trials (VTs) and commercial production (CP). This paper examines VT and CP data for tonnes of cane per hectare (TCH) and sugar content (CCS). Data, analysed by REML, included 107 VTs and 54 CP mill years for 9 varieties from the mill districts of Mulgrave, Babinda, and Tully for harvest years 1982-99. Important consistencies included high TCH of Q152, high CCS of Q117 and Q120, and low CCS of H56-752. Significant anomalies existed with respect to TCH for Q113, Q117, Q120, Q122, Q138, and H56-752 and to CCS for Q113 and Q124. Investigation of these anomalies was assisted by access to independent REML analyses of CP data for 65692 individual Tully cane blocks from 1988 to 1999 and by the knowledge of persons familiar with the preferential uses of varieties by farmers. Minor anomalies were due to limited year or mill area data. Q124 TCH was deemed to be decreased and its CCS increased by severe disease in Babinda CP in the extremely wet 1998 and 1999 seasons. Other serious anomalies have credible but unsubstantiated explanations. The most convincing, for Q113, Q117, Q138, and H56-752, are that these varieties were deployed unevenly with regard to late season harvesting, predominant use or avoidance on high fertility soils, or use confined to low fertility sandy soils, respectively. Uneven deployment results in confounding of these effects in the varietal CP statistics at mill area level. It is concluded that VTs cannot be enhanced to anticipate or evaluate most effects of uneven deployment. They give adequate predictions of relative CP performance for varieties deployed evenly across confounding influences. Routine analyses of individual block CP data would be useful and enhanced by addition of relevant information to the block records.
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Objective: To demonstrate the utility of a practical measure of lean mass for monitoring changes in the body composition of athletes. Methods: Between 1999 and 2003 body mass and sum of seven skinfolds were recorded for 40 forwards and 32 backs from one Super 12 rugby union franchise. Players were assessed on 13 (7) occasions ( mean (SD)) over 1.9 (1.3) years. Mixed modelling of log transformed variables provided a lean mass index (LMI) of the form mass/skinfolds(x), for monitoring changes in mass controlled for changes in skinfold thickness. Mean effects of phase of season and time in programme were modelled as percentage changes. Effects were standardised for interpretation of magnitudes. Results: The exponent x was 0.13 for forwards and 0.14 for backs ( 90% confidence limits +/- 0.03). The forwards had a small decrease in skinfolds ( 5.3%, 90% confidence limits +/- 2.2%) between preseason and competition phases, and a small increase ( 7.8%, 90% confidence limits +/- 3.1%) during the club season. A small decrease in LMI (similar to 1.5%) occurred after one year in the programme for forwards and backs, whereas increases in skinfolds for forwards became substantial (4.3%, 90% confidence limits +/- 2.2%) after three years. Individual variation in body composition was small within a season (within subject SD: body mass, 1.6%; skinfolds, 6.8%; LMI, 1.1%) and somewhat greater for body mass (2.1%) and LMI (1.7%) between seasons. Conclusions: Despite a lack of substantial mean changes, there was substantial individual variation in lean mass within and between seasons. An index of lean mass based
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Secondary fibre paper mills are significant users of both heat and electricity which is mainly derived from the combustion of fossil fuels. The cost of producing this energy is increasing year upon year. These mills are also significant producers of fibrous sludge and reject waste material which can contain high amounts of useful energy. Currently the majority of these waste fractions are disposed of by landfill, land-spread or incineration using natural gas. These disposal methods not only present environmental problems but are also very costly. The focus of this work was to utilise the waste fractions produced at secondary fibre paper mills for the on-site production of combined heat and power (CHP) using advanced thermal conversion methods (gasification and pyrolysis), well suited to relatively small scales of throughput. The heat and power can either be used on-site or exported. The first stage of the work was the development of methods to condition selected paper industry wastes to enable thermal conversion. This stage required detailed characterisation of the waste streams in terms of proximate and ultimate analysis and heat content. Suitable methods to dry and condition the wastes in preparation for thermal conversion were also explored. Through trials at pilot scale with both fixed bed downdraft gasification and intermediate pyrolysis systems, the energy recovered from selected wastes and waste blends in the form of product gas and pyrolysis products was quantified. The optimal process routes were selected based on the experimental results, and implementation studies were carried out at the selected candidate mills. The studies consider the pre-processing of the wastes, thermal conversion, and full integration of the energy products. The final stage of work was an economic analysis to quantify economic gain, return on investment and environmental benefits from the proposed processes.
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We report on the development of an ultraviolet curable hydrogel, based on combinations of poly(ethylene glycol) dimethacrylate (PEGMA), acrylic acid (AA) and N-Isopropylacrylamide (NIPPAm) for imprint lithography processes. The hydrogel was successfully imprinted to form dynamic microlens arrays. The response rate of the microlenses by volume change to water absorption was studied optically showing tunable focalisation of the light. Important optical refractive index change was measured between the dry and wet state of the microlenses. Our work suggests the use of this newly developed printable hydrogel for various imprinted components for sensing and imaging systems. © 2013 Elsevier B.V. All rights reserved.
Resumo:
The detailed organic composition of atmospheric fine particles with an aerodynamic diameter smaller than or equal to 2.5 micrometers (PM2.5) is an integral part of the knowledge needed in order to fully characterize its sources and transformation in the environment. For the study presented here, samples were collected at 3-hour intervals. This high time resolution allows gaining unique insights on the influence of short- and long-range transport phenomena, and dynamic atmospheric processes. A specially designed sequential sampler was deployed at the 2002-2003 Baltimore PM-Supersite to collect PM2.5 samples at a 3-hourly resolution for extended periods of consecutive days, during both summer and winter seasons. Established solvent-extraction and GC-MS techniques were used to extract and analyze the organic compounds in 119 samples from each season. Over 100 individual compounds were quantified in each sample. For primary organics, averaging the diurnal ambient concentrations over the sampled periods revealed ambient patterns that relate to diurnal emission patterns of major source classes. Several short-term releases of pollutants from local sources were detected, and local meteorological data was used to pinpoint possible source regions. Biogenic secondary organic compounds were detected as well, and possible mechanisms of formation were evaluated. The relationships between the observed continuous variations of the concentrations of selected organic markers and both the on-site meteorological measurements conducted parallel to the PM2.5 sampling, and the synoptic patterns of weather and wind conditions were also examined. Several one-to-two days episodes were identified from the sequential variation of the concentration observed for specific marker compounds and markers ratios. The influence of the meteorological events on the concentrations of the organic compounds during selected episodes was discussed. It was observed that during the summer, under conditions of pervasive influence of air masses originated from the west/northwest, some organic species displayed characteristics consistent with the measured PM2.5 being strongly influenced by the aged nature of these long-traveling background parcels. During the winter, intrusions from more regional air masses originating from the south and the southwest were more important.
Resumo:
The detailed organic composition of atmospheric fine particles with an aerodynamic diameter smaller than or equal to 2.5 micrometers (PM 2.5) is an integral part of the knowledge needed in order to fully characterize its sources and transformation in the environment. For the study presented here, samples were collected at 3-hour intervals. This high time resolution allows gaining unique insights on the influence of short- and long-range transport phenomena, and dynamic atmospheric processes. A specially designed sequential sampler was deployed at the 2002-2003 Baltimore PM Supersite to collect PM2.5 samples at a 3-hourly resolution for extended periods of consecutive days, during both summer and winter seasons. Established solvent-extraction and GC-MS techniques were used to extract and analyze the organic compounds in 119 samples from each season. Over 100 individual compounds were quantified in each sample. For primary organics, averaging the diurnal ambient concentrations over the sampled periods revealed ambient patterns that relate to diurnal emission patterns of major source classes. Several short-term releases of pollutants from local sources were detected, and local meteorological data was used to pinpoint possible source regions. Biogenic secondary organic compounds were detected as well, and possible mechanisms of formation were evaluated. The relationships between the observed continuous variations of the concentrations of selected organic markers and both the on-site meteorological measurements conducted parallel to the PM2.5 sampling, and the synoptic patterns of weather and wind conditions were also examined. Several one-to-two days episodes were identified from the sequential variation of the concentration observed for specific marker compounds and markers ratios. The influence of the meteorological events on the concentrations of the organic compounds during selected episodes was discussed. It was observed that during the summer, under conditions of pervasive influence of air masses originated from the west/northwest, some organic species displayed characteristics consistent with the measured PM2.5 being strongly influenced by the aged nature of these long-traveling background parcels. During the winter, intrusions from more regional air masses originating from the south and the southwest were more important.
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The longshore sediment transport (LST) is determinant for the occurrence of morphological changes in coastal environments. Understanding their movement mechanisms and transport is an essential source of information for the project design and coastal management plans. This study aims to characterize, initially, the active hydrodynamic circulation in the study area, comprised of four beach sectors from the south coast of Natal, assessing the average annual LST obtained through three proven equations (CERC, Kamphuis and Bayram et al.), defining the best formulation for the study area in question, and analyze the seasonal variability and the decadal transport evolution. The coastal area selected for this work constitutes one of the main tourist corridors in the city, but has suffered serious damage resulting from associated effects of hydrodynamic forcings and their disorderly occupation. As a tool was used the Coastal Modelling System of Brazil (SMC-Brazil), which presents integrated a series of numerical models and a database, properly calibrated and validated for use in developing projects along the Brazilian coastline. The LST rates were obtained for 15 beach profiles distributed throughout the study area. Their extensions take into account the depth of closure calculated by Harllermeier equation, and regarding the physical properties of the sediment, typical values of sandy beaches were adopted, except for the average diameter, which was calculated through an optimization algorithm based on equilibrium profile formulation proposed by Dean. Overall, the results showed an intensification of hydrodynamic forcings under extreme sea wave conditions, especially along the headlands exist in the region. Among the analyzed equations, Bayram et al. was the most suitable for this type of application, with a predominant transport in the south-north direction and the highest rates within the order of 700.000 m3 /year to 2.000.000 m3 /year. The seasonal analysis also indicated a longitudinal transport predominance in the south to north, with the highest rates associated with the fall and winter seasons. In these periods are observed erosive beach states, which indicate a direct relationship between the sediment dynamics and the occurrence of more energetic sea states. Regarding the decadal evolution of transportation, it was found a decrease in transport rate from the 50’s to the 70’s, followed by an increase until the 2000’s, coinciding with the beginning of urbanization process in some stretches of the studied coastline.
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This work aims to manufacture and characterize a hybrid plastic composite with the matrix isophthalic polyester resin base and having as reinforcing glass fiber and the dry endocarp of coconut (Coco nucifera Linn) in the form of particles as filler. The composite was made industrially in Tecniplas Industry and Trade LTDA. in the form of plate, and was manufactured process made by the manual lamination (Hand Lay Up). From the plate they were prepared test specimens for testing density, water absorption, uniaxial traction in dry and wet states, and testing of bending, as well as studies on the behavior of the generated fractures, macroscopic and microscopic, in mechanical tests through. All tests were performed in order to find the most viable applications the hybrid composite manufactured. The tensile and bending tests were analyzed last tensile properties, elasticity and deformation module. After the studies, it is observed that the percentage moisture absorbed was 3.03%. The presence of moisture in the tensile test meant a decrease of 19.77% from last stand, and 5.26% in the elastic modulus. For bending tests gave an average value of 69.13 MPa flexural strength. The results show the application of hybrid composite studied in lightweight structures, indoors, which require low / medium performance traction demands, and which involve flexural requests.
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The micro-deformations caused by cyclic loading origins the variation of the distances between atoms of the crystal lattice producing the irreversible component. In order to study and understand the microstructural behavior of the material this paper investigated the influence suffered by residual stresses in thrust rolling bearing races fabricated in AISI 52100 steel, after tests by cyclic rolling contact in a tribometer at 1m/s under two contact pressures (500 MPa and 1400 MPa) in dry and boundary lubrication conditions. Procedures of tests thermo-acustically isolated were developed for monitoring the contact temperature and sound pressure level signals to establish a comparison between the residual stress measurements, micro-hardness Vickers and micrographic registers searching an indication of wear evolution. The sin²ψ method by X-ray diffraction technique was used to quantify the residual stresses. Three raceway zones were selected for the evaluation of wear and surface morphology after predetermined cycling, comparing with their new condition ("as received"). Micro-hardness and residual stress measurements showed significant changes after the tests and it was possible to observe the relationship between the increase of sound pressure level and the residual stress for dry and lubricated conditions.
Resumo:
The micro-deformations caused by cyclic loading origins the variation of the distances between atoms of the crystal lattice producing the irreversible component. In order to study and understand the microstructural behavior of the material this paper investigated the influence suffered by residual stresses in thrust rolling bearing races fabricated in AISI 52100 steel, after tests by cyclic rolling contact in a tribometer at 1m/s under two contact pressures (500 MPa and 1400 MPa) in dry and boundary lubrication conditions. Procedures of tests thermo-acustically isolated were developed for monitoring the contact temperature and sound pressure level signals to establish a comparison between the residual stress measurements, micro-hardness Vickers and micrographic registers searching an indication of wear evolution. The sin²ψ method by X-ray diffraction technique was used to quantify the residual stresses. Three raceway zones were selected for the evaluation of wear and surface morphology after predetermined cycling, comparing with their new condition ("as received"). Micro-hardness and residual stress measurements showed significant changes after the tests and it was possible to observe the relationship between the increase of sound pressure level and the residual stress for dry and lubricated conditions.
Resumo:
The consumption of a product is directly linked to its quality, and are required to comply with quality standard regulations. In chicken "griller" which comes from industrial strains, selected for best growth performance, shot with up to 35 days old and weighing 1,400kg, they have not been reported in the literature a number of quality aspects This study aimed determine the muscle transformation time in the flesh in chickens "griller" incidence of meat defects, "PSE" (pale, soft and exdudative) and "DFD" (dark, firm and dry) and their correlation between different window times slaughter (total time between beginning of the fasting and the time of slaughter) and pH curve, four different times post mortem. The base data for the study was composed of information of 208 chickens, collected between August and September 2014, in a slaughterhouse slaughtering chickens in the middle region of Triangulo Mineiro and Alto Paranaíba. We used the Minitab 17.1.0 program for the development of descriptive statistical analysis and Pareto charts. The Pearson correlation was used to evaluate the linear relationship between two variables and Excel 2013, Microsoft Office®, to produce tables and graphs. The analysis consisted of 11 chickens cities and the distance to the poultry slaughterhouse ranged from 24.5 km to 123 km. It was observed that the pH curve decays gradually until time 5horas after slaughter, and its increase was 24, indicating the transformation of the muscle meat. The incidence of regular meat was 39.9%, "DFD" 30.3% and "PSE" 29.8%. For "DFD" meat, it was observed that factors: low ambient temperature, longer transportation and fast window and mileage at dirt road, contributed to its occurrence (p <0.05). For "PSE" meat, it was observed that lower body weight factors, longer transport favored frequency (p <0.05) of the meat defect. There was no significant correlation in variance analysis between distance, waiting time at rest shed and humidity related to meat defects (p> 0.05). This high incidence of defects meat may be due to pre-slaughter stress factors.
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In this thesis it is shown that the cosmogenic radionuclide 10Be proved to be a sensitive stratigraphic tool for sediment cores from the Arctic Ocean with low or negligible content of biogenic carbonate, impeding a reliable 0180 stratigraphy. 10Be enables a stratigraphy of Arctic sediments comparable to the d18O stratigraphy Imbrie et al. [1984] in that high concentration of 10Be are related to interglacial stages in contrast to lower values during glacial periods. To use the °Be profile as dating tool it is necessary to investigate the sources and sinks as well as the pathways of this radiotracer. 10Be is produced in the upper atmosphere and transfered to the earth's surface by dry and wet deposition. Besides the atmospheric component there is an important input of 10Be with the rivers to the Arctic Ocean. I determined depositional 10Be fluxes in the shelf area of the Laptev Sea, which is characterized by a huge input of river water, the continental slope of the Laptev Sea, the central Arctic Ocean and the Norwegian- and Greenland Sea. The depositional 10Be fluxes of (20 ± 5) x 10**6 atoms/cm**2/a in the shelf area of the Laptev Sea are by two orders of magnitude higher than the recent atmospheric input (0.2 - 0.5) x 10**6 atoms/cm**2/a in Greenland. while the fluxes in the central Arctic Ocean are in the same range. Further I developed a model to reconstruct the pathways of radionuclides 230Th, 231Pa and 10Be in high northern latitudes. The modelling results were compared with the measured concentrations in the water column and the recent depositional fluxes. These results show that the recent pathways of these nuclides can be rebuild by this model. Thus we can apply this model to earlier oxygen isotope stages to find out which predominate conditions lead to the determined depositional fluxes.
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Lake Meerfelder Maar (Germany) provides a varved record from the Last Glacial/Interglacial transition back to ca 1500 years BP. This study shows results for the Holocene sequence from new cores collected in 2009 based on varve counting, microfacies and micro-XRF analyses. The main goal of combining those analyses is to provide a new approach for interpreting long-term palaeolimnological proxy data and testing the climate-proxy stationarity throughout the current interglacial period. Varve counting provides a new independent Holocene chronology (MFM2012) with an estimated counting error of 1-0.5% and supported by 14C dating. Varve structure and thickness and geochemical composition of the varves give information about the main environmental processes that affect the lake and its catchment as well as the possible climate variability behind. Varves are couplets of i) a spring/summer laminae composed of monospecific diatom blooms and ii) an autumn/winter sub-layer made of minerogenic material and re-worked sediments. Thickness of the varves and sub-layers reflect lake variability and allow seasons to be distinguished as well as seasonal proxies. Changes in the winter minerogenic influx into the lake are reflected by Ti intensities and the Si/Ti ratio as a indicator for diatom concentration, which can be used as a proxy for water circulation during the early spring. Long-term variability of geochemical composition shows a reduction of the detrital material input (Ti) at 5,000 varve yrs BP and a visible sensitivity to water mixing (Si/Ti) during the Late Holocene. Variations of Ti intensities during the early and mid-Holocene do not show a clear relationship with climate. In contrast, higher values of the Si/Ti ratio together with thicker varves have been interpreted as wind-stress phases, which coincide with centennial variability of European cold/wet episodes during the Late Holocene. Our findings show that a long-term change in the lake and/or variability of the climate system can influence proxy sensitivity of a lacustrine record.