918 resultados para Persistence of Profits


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We employ a numerical model of cusp ion precipitation and proton aurora emission to fit variations of the peak Doppler-shifted Lyman-a intensity observed on 26 November 2000 by the SI-12 channel of the FUV instrument on the IMAGE satellite. The major features of this event appeared in response to two brief swings of the interplanetary magnetic field (IMF) toward a southward orientation. We reproduce the observed spatial distributions of this emission on newly opened field lines by combining the proton emission model with a model of the response of ionospheric convection. The simulations are based on the observed variations of the solar wind proton temperature and concentration and the interplanetary magnetic field clock angle. They also allow for the efficiency, sampling rate, integration time and spatial resolution of the FUV instrument. The good match (correlation coefficient 0.91, significant at the 98% level) between observed and modeled variations confirms the time constant (about 4 min) for the rise and decay of the proton emissions predicted by the model for southward IMF conditions. The implications for the detection of pulsed magnetopause reconnection using proton aurora are discussed for a range of interplanetary conditions.

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Purpose – This paper aims to investigate the scale and drivers of cross-border real estate development in Western Europe and Central and Eastern Europe. Design/methodology/approach – Placing cross-border real estate development within the framework of foreign direct investment (FDI), conceptual complexities in characterizing the notional real estate developer are emphasized. Drawing upon a transaction database, this paper proxies cross-border real estate development flows with asset sales by developers. Findings – Much higher levels of market penetration by international real estate developers are found in the less mature markets of Central and Eastern Europe. Analysis suggests a complex range of determinants with physical distance remaining a consistent barrier to cross-border development flows. Originality/value – This analysis adds significant value in terms of understanding cross-border real estate development flows. In this study, a detailed examination of the issues based on a rigorous empirical analysis through gravity modelling is offered. The gravity framework is one of the most confirmed empirical regularities in international economics and commonly applied to trade, FDI, migration, foreign portfolio investment inter alia. This paper assesses the extent to which it provides useful insights into the pattern of cross-border real estate development flows.

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This paper presents evidence of the discovery of a new Middle Pleistocene site in central southern England, with undisturbed evidence of hominin occupation well-dated to an interstadial towards the end of Marine Isotope Stage 8, c. 250,000 BP. The site consists of a preserved remnant of a river terrace and its alluvial floodplain overlain by chalk-rich bankside deposits, all abutting a Chalk bedrock riverbank. It preserves an area of occupation with activity focused on the riverbank, complemented by occasional activity on a palaeo-landsurface developed on the surface of the alluvial floodplain. Lithic technology at the site consists almost entirely of handaxe manufacture, allowing attribution to an Acheulian industrial tradition. Mammalian and other palaeo-environmental remains are present and associated with the occupation horizons, including large mammal bones showing signs of hominin interference. Dating was based on OSL determinations on the sediments and amino acid racemisation of molluscan remains, supported by biostratigraphic indications. Besides being a rare instance of an undisturbed Palaeolithic palaeo-landscape covering several hectares, the site contributes to wider Quaternary research concerns over the ability of Middle Pleistocene hominins to tolerate colder climatic episodes in higher latitudes, and over settlement history and changing lithic industrial traditions of northwest Europe in relation to climate change and British peninsularity. It is suggested that the Harnham evidence may represent an insular population that had persisted in southern Britain since MIS 10/9, which became locally extinct during the glacial maximum 8.2 marking the end of MIS 8.

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The mechanisms responsible for the generation and maintenance of immunological memory to Plasmodium are poorly understood and the reasons why protective immunity in humans is so difficult to achieve and rapidly lost remain a matter for debate. A possible explanation for the difficulty in building up an efficient immune response against this parasite is the massive T cell apoptosis resulting from exposure to high-dose parasite Ag. To determine the immunological mechanisms required for long-term protection against P. chabaudi malaria and the consequences of high and low acute phase parasite loads for acquisition of protective immunity, we performed a detailed analysis of T and B cell compartments over a period of 200 days following untreated and drug-treated infections in female C57BL/6 mice. By comparing several immunological parameters with the capacity to control a secondary parasite challenge, we concluded that loss of full protective immunity is not determined by acute phase parasite load nor by serum levels of specific IgG2a and IgG1. Abs, but appears to be a consequence of the progressive decline in memory T cell response to parasites, which occurs similarly in untreated and drug-treated mice with time after infection. Furthermore, by analyzing adoptive transfer experiments, we confirmed the major role of CD4(+) T cells for guaranteeing long-term full protection against P. chabaudi malaria. The Journal of Immunology, 2008, 181: 8344-8355.

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We estimate the effect of firms' profitability on wage determination for the American economy. Two standard bargaining models are used to illustrate the problems caused by the endogeneity of profits-per-worker in a real wage equation. The profit-sharing parameter can be identified with instruments which shift demando Using information from the input-output table, we create demand-shift variables for 63 4-digit sectors of the US manufacturing sector. The LV. estimates show that profit-sharing is a relevant and widespread phenomenon. The elasticity of wages with respect to profits-per-worker is seven times as large as OLS estimates here and in previous papers. Sensitivity analysis of the profit-sharing parameter controlling for the extent of unionization and product market concentration reinforces our results.

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We use the Ramsey model of g,Towth elaborated by Bliss [1995] and Ventlira [1997] to show how international integration results in long-nm persistellce Df GNPs distribution, while allowing, under certain conditions on parameters, for convergellce during the transition. First, we pi·ovide relationships which explicitly relate, in the neighborhood of the steady-state, the magnitude of conditional convergence or divergence to the fundamentaIs of the economies. Second, we present ali analysis of the Cobb Douglas case with a broad dass of utility functions and show that there is always transitional convergenee with this technology. Third, directions for testing the Illodel against the traditional dosed-ecollomy setting are proposed. These lead to adding specific and world-wide regTessors to traditional growth regressions.

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The aim of this study was to evaluate the persistence of methacrylate-based cement residues on the dentin, after dentin surface cleaning with ethanol or acetone, with or without previous application of a dentin adhesive. Forty bovine crown fragments were obtained and the dentin surface was washed with 1.0 mL of 2.5% sodium hypochlorite (NaOCl), followed by 0.1 mL of 17% ethylenediaminetetraacetic acid application for 3 min, and final irrigation with 2.5% NaOCl. The specimens were air dried and resin-based cement was rubbed onto the dentine surface with a microbrush applicator. In 20 specimens, previously to cement, a dentin adhesive was applied in all surfaces. After 15 min, the surface was scrubbed with a cotton pellet and moistened with ethanol or acetone, compounding the following groups: G199.5% ethanol and G2acetone, without previous use of dentin adhesive; G399.5% ethanol and G4acetone, with previous use of dentin adhesive. The dentin surface was scrubbed until the cement residues could not be visually detected. Sections were then processed for scanning electron microscopy and evaluated at 500x magnification and scores were attributed to each image according to the area covered by residual sealer, and data were subjected to KruskalWallis at 5% significance. The lower residue presence was observed in G3 (P = 0.005). All surface presented cement residues when acetone was used as cleaning solution (P = 0.0005). The cleaning solutions were unable to completely remove the cement residues from both surfaces. The ethanol used after previous application of the dentin adhesive promoted the lower presence of residues.

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The aim of this study was to evaluate the persistence of resin cement residues after dentin surface cleaning with different alcohol-based solutions or an essential oil (eucalyptol). Forty bovine teeth were sectioned in order to expose pulp chamber dentin to be washed with 1.0 mL of 2.5% sodium hypochlorite (NaOCl), followed by 0.1 mL of 17% EDTA application for 3 min, and final irrigation with 2.5% NaOCl. The specimens were air dried and resin-based cement was rubbed onto the dentine surface with a microbrush applicator. After 15 min, the surface was scrubbed with a cotton pellet and moistened with different dentin cleaning solutions, compounding the following groups: G195% ethanol, G270% ethanol, G370% isopropyl alcohol, or G4eucalyptol. The dentin was scrubbed until the cement residues could not be visually detected. Sections were then processed for SEM and evaluated at x 500 magnification. Scores were attributed to each image according to the area covered by residual sealer, and data were subjected to KruskalWallis at 5% significance. Eucalyptol promoted the most adequate dentin cleaning, although no statistical difference was detected amongst the groups (P > 0.05), except between the eucalyptol and 70% ethanol groups (P < 0.05). All the evaluated dentin cleaning solutions were unable to completely remove the cement residues from the dentin surface. Microsc. Res. Tech., 2012. (C) 2012 Wiley Periodicals, Inc.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The persistence of five pesticides (acephate, azinphos methyl, carbendazim, diazinon and dimethoate) in peach fruit was studied in real operating conditions. Pesticides showed different degradation rates. Diazinon was degraded with a half-life (t(1/2)) of 5.2 days, acephate, azinphos methyl and dimethoate with t(1/2) of ca 12 days and carbendazim with t(1/2) of 15.5 days. After the pre-harvest interval (PHI) all pesticide residues were within the limits established by Italian law.

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In this paper, the effect of age, humidity, and temperature on the conidial survival of Entomophthora muscae was evaluated. E. muscae was obtained from Musca domestica in a dairy in Itatiba (São Paulo, Brazil) and maintained in the laboratory by continuous passage through flies. Furthermore, the ability of conidia to infect flies at three temperatures (17, 21, and 27 degrees C), four ages of conidia (12, 72, 96, and 154 hours) and two humidities (100 and 60% RH) was evaluated. The temperature of 21 degrees C was the most favorable for the infection of house flies. Humidity was a cause of variation at 27 degrees C when the conidia were up to 12 hours old, but had no effect at lower temperatures. Conidia held at 100% RH and aged 72 hours caused no infection at 17 degrees C, but were infective at 21 degrees C. In the present study, conidia retained viability much longer than previously observed. Finally, the effect of humidity, temperature, and conidial age is discussed.

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The decay rate of six insecticides (azinphos methyl, diazinon, dimethoate, methidathion, parathion methyl, and quinalphos) used to control Dacus oleae was studied. Degradation of pesticides showed pseudo-first-order kinetics with correlation coefficients ranging between -0.936 and -0.998 and half-lives between 4.3 days for dimethoate and 10.5 days for methidathion. Residues in olive oil were greater than on olives, with a maximum concentration factor of 7. Dimethoate was the only pesticide with lower residues in the oil than on the fruits. Olive washing affects pesticide residues ranging from no reduction to a 45% decrease. During 8 months of storage of the olive oil, diazinon, dimethoate, parathion methyl, and quinalphos did not show any remarkable difference, while methidathion and azinphos methyl showed a moderate decrease.