952 resultados para inter-ring variation
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Lake surface water temperatures (LSWTs) of 246 globally distributed large lakes were derived from Along-Track Scanning Radiometers (ATSR) for the period 1991–2011. The climatological cycles of mean LSWT derived from these data quantify on a global scale the responses of large lakes' surface temperatures to the annual cycle of forcing by solar radiation and the ambient meteorological conditions. LSWT cycles reflect the twice annual peak in net solar radiation for lakes between 1°S to 12°N. For lakes without a lake-mean seasonal ice cover, LSWT extremes exceed air temperatures by 0.5–1.7 °C for maximum and 0.7–1.9 °C for minimum temperature. The summer maximum LSWTs of lakes from 25°S to 35°N show a linear decrease with increasing altitude; −3.76 ± 0.17 °C km−1 (inline image = 0.95), marginally lower than the corresponding air temperature decrease with altitude −4.15 ± 0.24 °C km−1 (inline image = 0.95). Lake altitude of tropical lakes account for 0.78–0.83 (inline image) of the variation in the March to June LSWT–air temperature differences, with differences decreasing by 1.9 °C as the altitude increases from 500 to 1800 m above sea level (a.s.l.) We define an ‘open water phase’ as the length of time the lake-mean LSWT remains above 4 °C. There is a strong global correlation between the start and end of the lake-mean open water phase and the spring and fall 0 °C air temperature transition days, (inline image = 0.74 and 0.80, respectively), allowing for a good estimation of timing and length of the open water phase of lakes without LSWT observations. Lake depth, lake altitude and distance from coast further explain some of the inter-lake variation in the start and end of the open water phase.
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Establishing metrics to assess machine translation (MT) systems automatically is now crucial owing to the widespread use of MT over the web. In this study we show that such evaluation can be done by modeling text as complex networks. Specifically, we extend our previous work by employing additional metrics of complex networks, whose results were used as input for machine learning methods and allowed MT texts of distinct qualities to be distinguished. Also shown is that the node-to-node mapping between source and target texts (English-Portuguese and Spanish-Portuguese pairs) can be improved by adding further hierarchical levels for the metrics out-degree, in-degree, hierarchical common degree, cluster coefficient, inter-ring degree, intra-ring degree and convergence ratio. The results presented here amount to a proof-of-principle that the possible capturing of a wider context with the hierarchical levels may be combined with machine learning methods to yield an approach for assessing the quality of MT systems. (C) 2010 Elsevier B.V. All rights reserved.
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The aim of this study is to evaluate the variation of solar radiation data between different data sources that will be free and available at the Solar Energy Research Center (SERC). The comparison between data sources will be carried out for two locations: Stockholm, Sweden and Athens, Greece. For the desired locations, data is gathered for different tilt angles: 0°, 30°, 45°, 60° facing south. The full dataset is available in two excel files: “Stockholm annual irradiation” and “Athens annual irradiation”. The World Radiation Data Center (WRDC) is defined as a reference for the comparison with other dtaasets, because it has the highest time span recorded for Stockholm (1964–2010) and Athens (1964–1986), in form of average monthly irradiation, expressed in kWh/m2. The indicator defined for the data comparison is the estimated standard deviation. The mean biased error (MBE) and the root mean square error (RMSE) were also used as statistical indicators for the horizontal solar irradiation data. The variation in solar irradiation data is categorized in two categories: natural or inter-annual variability, due to different data sources and lastly due to different calculation models. The inter-annual variation for Stockholm is 140.4kWh/m2 or 14.4% and 124.3kWh/m2 or 8.0% for Athens. The estimated deviation for horizontal solar irradiation is 3.7% for Stockholm and 4.4% Athens. This estimated deviation is respectively equal to 4.5% and 3.6% for Stockholm and Athens at 30° tilt, 5.2% and 4.5% at 45° tilt, 5.9% and 7.0% at 60°. NASA’s SSE, SAM and RETScreen (respectively Satel-light) exhibited the highest deviation from WRDC’s data for Stockholm (respectively Athens). The essential source for variation is notably the difference in horizontal solar irradiation. The variation increases by 1-2% per degree of tilt, using different calculation models, as used in PVSYST and Meteonorm. The location and altitude of the data source did not directly influence the variation with the WRDC data. Further examination is suggested in order to improve the methodology of selecting the location; Examining the functional dependence of ground reflected radiation with ambient temperature; variation of ambient temperature and its impact on different solar energy systems; Im pact of variation in solar irradiation and ambient temperature on system output.
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The cooperative behavior is no longer a dilemma for the theory of evolution, since there are models that explain the evolution of this behavior by means of natural selection at the individual level. However, there have been few studies on the proximal factors that interfere with cooperative behavior. In the study of the influence of cognition on cooperation, many authors have been interested in situations in which individuals decide whether to act cooperatively and select partners with different qualities to cooperate. Of the factors studied, we highlight the need for understanding the apparatus and communication between partners to the occurrence of cooperation. Recently, highlight is the proposal that the ability to cooperate would be greater in species with cooperative breeding system. Thus, the common marmoset (Callithrix jacchus) is a New World monkey which stands as a valuable species for this type of study because it presents cooperative actions in nature, such as sharing food and protection of the community territory. Our experiment investigated whether common marmosets unrelated females (n = 6) were able to cooperate using an electrical and a mechanical apparatus, if this cooperation is a byproduct of individual actions or involve social attention, if it occurs inter-individual variation in the use of devices and formation of roles (producer / scrounger) in dyads. We use the number of rewards obtained by animals (Ratio of Correct Pulls) as indicators of cooperation and glances for partners (Ratio of Correct Glances) as indicators of social attention and communication. The results indicate that the type of apparatus was not a constraint for the occurrence of cooperation between the marmosets, but still has not been verified formation of roles in the dyads. The performance of animals in the two devices showed a large variation in the learning time, not having relationship with the performance in the tests phase. In both devices the level of social glances at control phases were casually correlated with any other phase, but the data showed that there was not social attention, that is, the monkeys realized that they gave food to the partners, but the partners did
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Toxocariasis is caused by infection of man by Toxocara canis and Toxocara, cati larvae, the common roundworm of dogs and cats. Because larvae are difficult to detect in tissues, diagnosis is mostly based on serology. Non specific reactions are observed mainly due to cross-reactivity with Ascaris sp antigens. This investigation aimed at developing and evaluating an indirect antibody competition ELISA (IACE) employing a specific rabbit IgG anti-Toxocara canis excretory-secretory antigens as the competition antibody. in order to improve indirect ELISA specificity performed for toxocariasis diagnosis. For that, the rabbit IgG was previously absorbed by Ascaris suum adult antigens. Sensitivity and specificity of IACE were first evaluated in 28 serum samples of mice experimentally infected with T. canis embryonated eggs. Adopting cut-off value established in this population before infection, sensitivity and specificity were 100% after 20 days post-inoculation. For human population IACE was evaluated using sera from 440 patients with clinical signs of toxocariasis and the cut-off value was established with 60 serum samples from apparently healthy individuals. Using as reference test the indirect ELISA performed by Adolfo Lutz Institute, sensitivity was 60.2%, specificity was 98% and concordance was 77.3%. Repeatability of IACE was evaluated by the inter-reactions variation coefficient (2.4%).
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Amostras de cabelo foram utilizadas como bioindicador para avaliar os níveis de As, Cd, Pb e Hg na população residente na área "Volta Grande" do rio Xingu, no Norte do Brasil. As concentrações de As e Cd estão de acordo com os valores encontrados na literatura, no entanto, foram encontrados valores anômalos de Pb e Hg , o que pode sugerir uma variação inter-regional. Os elevados valores encontrados de Pb e Hg, em cabelos de moradores da Ilha do Canteiro, podem ser atribuídos à exposição ambiental das famílias, por estarem em uma área ambiental impactada pela mineração de ouro. A aplicação dos métodos de estatística multivariada mostrou que a concentração dos metais, estudados neste trabalho, pode ser classificatória entre pessoas de localidades diferentes do município de Altamira. Os resultados neste trabalho refletem o impacto ambiental destes elementos sobre a saúde dos habitantes desta área de garimpagem de ouro.
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Introduction: The literature about the work with the voice of actors in the theater focuses the research on organic issues involved in the vocal process as “misuse” or “vocal abuse”. To a lesser amount, there are studies that highlight issues of interpretation and expressive resources, as well as others that highlight the linguistic resources of interpretation. This work shows a linguistic feature – the pause – and its collaboration for the theatrical interpretation. Objective: to verify the extent to which similarities and differences occur between the points judged as occurrence of pauses in interpretations of a theatrical text. Method: Subjects of this study were four theater actors, who played individually a same theatrical text. Later, a group of ten judges judged the points where pauses occurred. Based on a criterion of 70% agreement between judges, were searched similarities and differences between the points judged as pause of each recording. Results: the four subjects showed different amounts of pause in the stretch in common that they interpreted: S1= ten occurrences; S2= 14 occurrences; S3= 6 occurrences; and S4= 9 occurrences. In this inter-subject variation, five points of pause in common were detected. Conclusion: we have seen, then, that this variability (featuring subjectivity in interpretation) is built inside given possibilities, with lesser or greater flexibility, by the structure of the theatrical text.
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The aim of this study was to evaluate the response of dopamine in the growth hormone secretion (GH) during Nellore heifer's sexual maturation. The animals were randomly assigned into two experimental groups: Sulpiride group (dopamine D-2 antagonist, 0.59 mg/kg, S. C.) and control group (saline solution S. C.) at 8, 12 and 16 months of age. Blood samples were collected every 15 min for 10h after drug injection. Growth hormone was quantified by RIA, sensitivity (0.25 ng/mL) and intra and inter-assay variation coefficients were 15% and 17%, respectively. GH concentration was higher in sulpiride group than control group at 8 mo (10.1 +/- 0.38 ng/mL vs 4.3 +/- 0.34 ng/mL; P < 0.05) and 12 mo of age (9.46 +/- 0.35 vs 3.74 +/- 0.19 ng/mL; P < 0.05). In sulpiride group GH average concentration was greater at 8 and 12 mo compared to 16 mo of age (10.10 +/- 0.38 ng/mL and 9.46 +/- 0.35 ng/mL vs 4.87 +/- 0.35 ng/mL; P < 0.05) respectively. There was no difference between groups (P > 0.05) in total GH secretion area, total peak area and maximum peak amplitude. These results suggested an inhibitory dopamine effect on GH secretion in pre-pubertal Nellore heifers that decreases according to age.
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The present work aims to update a series of information about the regional fishing production, by presenting and characterizing the contribution of the different sub-systems of the Amazon basin to the catch landed at the main fishing market of Manaus, Brazil, from 1994 to 1996. Collectors specifically hired for this function registered key information on the fisheries. Thirty nine types or groups of fish were found in the fishing production landed. Jaraqui (Semaprochilodus spp.), curimatã (Prochilodus nigricans), pacu (Myleinae), matrinchã (Brycon cephalus), sardine (Triportheus spp.), aracu (Anostomidae) and tambaqui (Colossoma macropomum) were the most important items during three consecutive years. In 1994 these items summed up 91.6% of the total production; in 1995 and 1996 these values were, respectively, 85.3% and 86.4% of the total production. Tambaqui landed decreased remarkably during the period 1976-1996. There was a strong seasonal component in the production of the main species; jaraqui and matrinchã were mostly landed between April and June, while curimatã, pacu, and sardine were mostly landed during the dry season. Other important items showed a strong inter-annual variation in their production. The fishing production landed came mostly from the sub-system of the Purus River (around 30% of the total production). The subsystem of the Medium-Solimões contributed with an average of 15% and the sub-systems of the Madeira, Lower-Solimões, Upper-Amazon and Juruá, together contributed with 11.5% of the total production landed. Finally, the remaining sub-systems contributed with only 7.6% of the production.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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We describe the karyotype of Thalpomys species, from different Brazilian localities of the Cerrado. Thalpomys cerradensis Herskovitz, 1990 showed 2n = 36, FN = 34 and T. lasiotis Thomas, 1916 2n = 38, FN = 38. Comparisons of G-band karyotypes showed evident inter-specific homologies indicating that their chromosome complements could be derived from one another by two presumed rearrangements. Both species showed pericentromeric C-band regions in almost all chromosomes but a comparison with CMA3/DA/DAPI staining indicated that the molecular content of heterochromatic regions was different. T. lasiotis specimens from two different localities differed in the morphology of the X chromosome due to the presence of a short heterochromatic arm. These chromosome types are apparently fixed in each population rather than maintained as a polymorphic variation. Phylogenetic analyses supported the monophyly of the genus Thalpomys but was not capable of elucidating its phylogenetic relationship to other Akodontini rodents. These analyses also showed inter-individual variation in T. lasiotis, even within a given population. Phylogenetic analyses placed T. lasiotis specimens with different karyotypes in different monophyletic branches. Molecular and karyologic data confirmed the identity of the genus Thalpomys.
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The spatial and temporal variation of microphytobenthic biomass in the nearshore zone of Martel Inlet (King George Island, Antarctica) was estimated at several sites and depths (10-60 m), during three summer periods (1996/1997, 1997/1998, 2004/2005). The mean values were inversely related to the bathymetric gradient: higher ones at 10-20 m depth (136.2 +/- A 112.5 mg Chl a m(-2), 261.7 +/- A 455.9 mg Phaeo m(-2)), intermediate at 20-30 m (55.6 +/- A 39.5 mg Chl a m(-2), 108.8 +/- A 73.0 mg Phaeo m(-2)) and lower ones at 40-60 m (22.7 +/- A 23.7 mg Chl a m(-2), 58.3 +/- A 38.9 mg Phaeo m(-2)). There was also a reduction in the Chl a/Phaeo ratio with depth, from 3.2 +/- A 3.2 (10-20 m) to 0.7 +/- A 1.0 (40-60 m), showing a higher contribution of senescent phytoplankton and/or macroalgae debris at the deeper sites and the limited light flux reaching the bottom. Horizontal differences found in the biomass throughout the inlet could not be clearly related to hydrodynamics or proximity to glaciers, but with sediment characteristics. An inter-summer variation was observed: the first summer presented the highest microphytobenthic biomass apparently related to more hydrodynamic conditions, which causes the deposition of allochthonous material.
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Durch geologische Prozesse freigesetzte sowie biogen und anthropogen emittierte Gase werden hauptsächlich von der untersten Atmosphärenschicht, der Troposphäre, aufgenommen und abgebaut. Durch in die Troposphä¬re einfallende solare Strahlung wird ein Abbau des Großteils der emittierten Spurengase durch reaktive Radikale initiiert. Der wichtigste Vertreter dieser reaktiven Radikale in der Troposphäre ist das Hydroxylradikal (OH-Radikal), welches im schnellen Gleichgewicht mit Hydroperoxyradikalen (HO2-Radikal) vorliegt, sodass die Summe aus OH- und HO2-Radikalen oft als HOx zusammengefasst wird. HOx-Radikale bilden tagsüber den Hauptteil der Oxidationskapazität der Troposphäre und sind somit verantwortlich für den oxidativen Abbau vieler, auch chemisch und photolytisch stabiler, Spurengase. Daher wird die Oxidationskapazität als Selbstreinigungskraft der Troposphäre verstanden. rnIm Rahmen meiner Arbeit wurde die wissenschaftliche Fragestellung auf die Oxidationskapazität der Troposphäre über Europa fokussiert. Die Höhen- und Breitenverteilung der OH- und HO2-Mischungsverhältnisse und ihre jahreszeitliche Variation wurde während der flugzeuggestützten HOOVER-Kampagnen (HOOVER 1 & 2) charakterisiert, wobei ein Fokus auf der oberen Troposphäre lag. Es wird gezeigt, welchen Einfluss die einfallende Strahlung, die Variation von HOx-Vorläufersubstanzen (wie z. B. Ozon) und die Variation von Substanzen, die das HOx-Gleichgewicht beeinflussen (z. B. Stickstoffmonoxid), auf das HOx-Budget haben. rnEs wird beispielhaft für den Höhenbereich zwischen 8 und 9.5 km gezeigt, dass die Oxidationskapazität in der oberen Troposphäre des Sommers im Ver¬gleich zu der des Herbstes aufgrund von einer verstärkten HO2-Zyklierung im Mittel deutlich erhöht ist (500 %). rnDurch konvektiven Transport werden im Sommer im Gegensatz zum Herbst regelmäßig Luftmassen aus der planetaren Grenzschicht in die obere Troposphäre eingemischt. Daher wurden der konvektive Luftmassentransport und der Einfluss der eingemischten Spurengase auf die Oxidationskapazität der oberen Troposphäre anhand eines konvektiven Elements über Südostdeutschland untersucht. Wie in dieser Arbeit berichtet wird, wurden in den Luftmassen der Ausströmregion mit bis zu 3.5 pmol/mol (Maximum 10 s-Mittelwert) sehr hohe OH-Mischungsverhältnisse gefunden, die aus der HO2-Konversion mit NO gebildet wurden. Das modellierte HOx-Budget zeigt, dass die HOx-Chemie - unter den beobachteten Bedingungen in der Ausströmregion - durch HOx-Zyklierungsreaktionen beherrscht wird. rnDie gemessenen OH-Mischungsverhältnisse in der Ausströmregion liegen etwa um einen Faktor fünf höher, als die während dieses Fluges in der konvektiv unbeeinflussten oberen Troposphäre gemessenen OH-Mischungsverhältnisse. Am Beispiel der NO2- und CH4-Lebensdauer wird ein schnellerer Abbau von Spurengasen aufgrund der erhöhten Oxidationskapazität nachgewiesen. Aus der NO2-Lebensdauer wird abgeschätzt, wie lange die Oxidationskapazität aufgrund des konvektiven Transports von NOx in den Luftmassen des Ausströmgebietes erhöht ist.rnDie während den Kampagnen durchgeführten Messungen wurden genutzt, um Modellberechnungen des vertikalen HOx-Budgets (über Südschweden) und des meridionalen HOx-Budgets zwischen Nordeuropa und Korsika durchzuführen. Es wurde gezeigt, dass das Modell die OH- und HO2-Mischungsverhältnisse im Allgemeinen gut reproduziert (Modell/Messung: OH im Sommer 94 %, HO2 im Sommer 93 % im Herbst 95 %), wohingegen die vergleichsweise kleinen OH-Mischungsverhältnisse im Herbst aufgrund von einer überschätzten H2O2 abhängigen OH-Produktion stark überschätzt wurden (Modell/Messung: 147 %). rnZur Charakterisierung der Oxidationskapazität innerhalb der planetaren Grenzschicht wurden die DOMINO-Kampagnen durchgeführt. Dabei wurde die Zusammensetzung unterschiedlicher Luftmassen untersucht, die aus verschiedenen Herkunftsorten zum Messort transportiert wurden und aufgrund ihres Ursprungs kaum prozessierte bis prozessierte anthropogen emittierte Spurengase enthielten. Zusätzlich enthielt ein Teil der Luftmassen biogen emittierte Spurengase. Komplementäre Messungen ermöglichen die Berechnung der totalen OH-Produktion und den Vergleich mit den bekannten OH-Quellen. Der Vergleich zeigt, dass offenbar wichtige OH-Produktionskanäle durch die gemessenen Spurengase oder die durchgeführten Berechnungen nicht abgebildet werden. Es wird gezeigt, dass die Stärke der unbekannten OH-Quellen, vor allem unter niedrigen NO-Bedingungen, groß ist und mit den Isopren-, RO2- und HO2-Mischungsverhältnissen korreliert.rn