943 resultados para vattenfri offset


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Background: In the British Isles, control of cattle tuberculosis (TB) is hindered by persistent infection of wild badger (Meles meles) populations. A large-scale field trial—the Randomised Badger Culling Trial (RBCT)—previously showed that widespread badger culling produced modest reductions in cattle TB incidence during culling, which were offset by elevated TB risks for cattle on adjoining lands. Once culling was halted, beneficial effects inside culling areas increased, while detrimental effects on adjoining lands disappeared. However, a full assessment of the utility of badger culling requires information on the duration of culling effects. Methodology/Principal Findings: We monitored cattle TB incidence in and around RBCT areas after culling ended. We found that benefits inside culled areas declined over time, and were no longer detectable by three years post-culling. On adjoining lands, a trend suggesting beneficial effects immediately after the end of culling was insignificant, and disappeared after 18 months post-culling. From completion of the first cull to the loss of detectable effects (an average five-year culling period plus 2.5 years post-culling), cattle TB incidence was 28.7% lower (95% confidence interval [CI] 20.7 to 35.8% lower) inside ten 100 km2 culled areas than inside ten matched no-culling areas, and comparable (11.7% higher, 95% CI: 13.0% lower to 43.4% higher, p = 0.39) on lands #2 km outside culled and no-culling areas. The financial costs of culling an idealized 150 km2 area would exceed the savings achieved through reduced cattle TB, by factors of 2 to 3.5. Conclusions/Significance: Our findings show that the reductions in cattle TB incidence achieved by repeated badger culling were not sustained in the long term after culling ended and did not offset the financial costs of culling. These results, combined with evaluation of alternative culling methods, suggest that badger culling is unlikely to contribute effectively to the control of cattle TB in Britain.

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Heterochrony, the change in timing of developmental processes, is thought to be a key process shaping the numerous limb morphologies of tetrapods. Through a delayed offset in digit development, all cetaceans (i.e., whales, dolphins, and porpoises) have evolved supernumary phalanges (hyperphalangy). Moreover, some toothed cetaceans further alter digital morphologies by delayed endochondral and perichondral ossification of individual elements. In the harbor porpoise (Phocoena phocoena), these paedomorphic patterns have created poorly ossified phalangeal elements. However, no studies have addressed this morphology in other porpoise taxa. This study documents the timing of carpal and digital epiphyseal ossification in the poorly studied vaquita (Phocoena sinus) based on radiographs (n = 18) of known-age specimens. Patterns of vaquita manus ossification were compared between other porpoise and delphinid taxa. Adult vaquitas are paedomorphic in carpal, metacarpal, and digital development as they maintain a juvenile ossification pattern relative to that of other porpoise species of equivalent ages. Vaquitas also ossify fewer carpal elements as compared to other porpoise and some delphinid cetaceans, and ossification arrests relative to that of the harbor porpoise. Vaquitas also display sexual dimorphism as females reach a greater body size and display more ossified elements in the manus relative to their paedomorphic male cohorts.

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A recent book (The Bourgeois Virtues: Ethics for an Age of Commerce, D. N. McCloskey), raises the matter of the role of the virtues in business and economic choice, arguing that capitalism can indeed, be virtuous or at least better than the alternative(s). This argument is especially timely in light of the apparent excesses on Wall Street and in some banking/financial institutions. Excessive greed and often the lack of business ethics contributed in substantive ways to the financial crisis and near economic meltdown we have been experiencing. As McCloskey, (2006, pp. 1-2) argues (in setting the stage for the complex argument made in this 616-page book!): “The book … is directed toward you who are suspicious of the phrase ‘bourgeois virtues,’ pretty sure that it is a contradiction in terms. And the book is directed, with less optimism about changing their minds, toward you who think the phrase is worse: a lie. ‘Bourgeois virtues’ is neither. The claim here is that modern capitalism does not need to be offset to be good. Capitalism can on the contrary be virtuous. In a fallen world bourgeois life is not perfect. But it’s better than any available alternative. American capitalism needs to be inspirited, moralized, completed. Two and a half cheers for the Midwestern bourgeoisie (middle-class, small business owners…. yet)… Many a businessman is an ethical shell or worse. Even the virtues of the bourgeoisie, … do not lead straight to heaven.”

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

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We present a new method to quantify substructures in clusters of galaxies, based on the analysis of the intensity of structures. This analysis is done in a residual image that is the result of the subtraction of a surface brightness model, obtained by fitting a two-dimensional analytical model (beta-model or Sersic profile) with elliptical symmetry, from the X-ray image. Our method is applied to 34 clusters observed by the Chandra Space Telescope that are in the redshift range z is an element of [0.02, 0.2] and have a signal-to-noise ratio (S/N) greater than 100. We present the calibration of the method and the relations between the substructure level with physical quantities, such as the mass, X-ray luminosity, temperature, and cluster redshift. We use our method to separate the clusters in two sub-samples of high-and low-substructure levels. We conclude, using Monte Carlo simulations, that the method recuperates very well the true amount of substructure for small angular core radii clusters (with respect to the whole image size) and good S/N observations. We find no evidence of correlation between the substructure level and physical properties of the clusters such as gas temperature, X-ray luminosity, and redshift; however, analysis suggest a trend between the substructure level and cluster mass. The scaling relations for the two sub-samples (high-and low-substructure level clusters) are different (they present an offset, i. e., given a fixed mass or temperature, low-substructure clusters tend to be more X-ray luminous), which is an important result for cosmological tests using the mass-luminosity relation to obtain the cluster mass function, since they rely on the assumption that clusters do not present different scaling relations according to their dynamical state.

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Communities in fragmented landscapes are often assumed to be structured by species extinction due to habitat loss, which has led to extensive use of the species-area relationship (SAR) in fragmentation studies. However, the use of the SAR presupposes that habitat loss leads species to extinction but does not allow for extinction to be offset by colonization of disturbed-habitat specialists. Moreover, the use of SAR assumes that species richness is a good proxy of community changes in fragmented landscapes. Here, we assessed how communities dwelling in fragmented landscapes are influenced by habitat loss at multiple scales; then we estimated the ability of models ruled by SAR and by species turnover in successfully predicting changes in community composition, and asked whether species richness is indeed an informative community metric. To address these issues, we used a data set consisting of 140 bird species sampled in 65 patches, from six landscapes with different proportions of forest cover in the Atlantic Forest of Brazil. We compared empirical patterns against simulations of over 8 million communities structured by different magnitudes of the power-law SAR and with species-specific rules to assign species to sites. Empirical results showed that, while bird community composition was strongly influenced by habitat loss at the patch and landscape scale, species richness remained largely unaffected. Modeling results revealed that the compositional changes observed in the Atlantic Forest bird metacommunity were only matched by models with either unrealistic magnitudes of the SAR or by models ruled by species turnover, akin to what would be observed along natural gradients. We show that, in the presence of such compositional turnover, species richness is poorly correlated with species extinction, and z values of the SAR strongly underestimate the effects of habitat loss. We suggest that the observed compositional changes are driven by each species reaching its individual extinction threshold: either a threshold of forest cover for species that disappear with habitat loss, or of matrix cover for species that benefit from habitat loss.

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The purpose of this study was to correlate the trochlear shape and patellar tilt angle and lateral patellar displacement at rest and maximal voluntary isometric contraction (MVIC) exercises during open (OKC) and closed kinetic chain (CKC) in subjects with and without anterior knee pain. Subjects were all women, 20 who were clinically healthy and 19 diagnosed with anterior knee pain. All subjects were evaluated and subjected to magnetic resonance exams during OKC and CKC exercise with the knee placed at 15, 30, and 45 degrees of flexion. The parameters evaluated were sulcus angle, patellar tilt angle and patellar displacement using bisect offset. Pearson's r coefficient was used, with p < .05. Our results revealed in knee pain group during CKC and OKC at 15 degrees that the increase in the sulcus angle is associated with a tilt increase and patellar lateral displacement. Comparing sulcus angle, patellar tilt angle and bisect offset values between MVIC in OKC and CKC in the knee pain group, it was observed that patellar tilt angle increased in OKC only with the knee flexed at 30 degrees. Based on our results, we conclude that reduced trochlear depth is correlated with increased lateral patellar tilt and displacement during OKC and CKC at 15 degrees of flexion in people with anterior knee pain. By contrast, 30 degrees of knee flexion in CKC is more recommended in rehabilitation protocols because the patella was more stable than in other positions.

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We performed ab initio calculations of the electronic structures of bulk CdSe and CdTe, and their interface band alignments on the CdSe in-plane lattice parameters. For this, we employed the LDA-1/2 self-energy correction scheme [L.G. Ferreira, M. Marques, L.K. Teles, Phys. Rev. B 78 (2008) 125116] to obtain corrected band gaps and band offsets. Our calculations include the spin-orbit effects for the bulk cases, which have shown to be of importance for the equilibrium systems and are possibly degraded in these strained semiconductors. Therefore, the SO showed reduced importance for the band alignment of this particular system. Moreover, the electronic structure calculated along the transition region across the CdSe/CdTe interface shows an interesting non-monotonic variation of the band gap in the range 0.8-1.8 eV, which may enhance the absorption of light for corresponding frequencies at the interface between these two materials in photovoltaic applications. (C) 2012 Elsevier B.V. All rights reserved.

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The industrial wastewater from resin production plants contains as major components phenol and formaldehyde, which are traditionally treated by biological methods. As a possible alternative method, electrochemical treatment was tested using solutions containing a mixture of phenol and formaldehyde simulating an industrial effluent. The anode used was a dimensionally stable anode (DSAA (R)) of nominal composition Ti/Ru0.3Ti0.7O2, and the solution composition during the degradation process was analyzed by liquid chromatography and the removal of total organic carbon. From cyclic voltammetry, it is observed that for formaldehyde, a small offset of the beginning of the oxygen evolution reaction occurs, but for phenol, the reaction is inhibited and the current density decreases. From the electrochemical degradations, it was determined that 40 mA cm(-2) is the most efficient current density and the comparison of different supporting electrolytes (Na2SO4, NaNO3, and NaCl) indicated a higher removal of total organic carbon in NaCl medium.

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A semi-autonomous unmanned underwater vehicle (UUV), named LAURS, is being developed at the Laboratory of Sensors and Actuators at the University of Sao Paulo. The vehicle has been designed to provide inspection and intervention capabilities in specific missions of deep water oil fields. In this work, a method of modeling and identification of yaw motion dynamic system model of an open-frame underwater vehicle is presented. Using an on-board low cost magnetic compass sensor the method is based on the utilization of an uncoupled 1-DOF (degree of freedom) dynamic system equation and the application of the integral method which is the classical least squares algorithm applied to the integral form of the dynamic system equations. Experimental trials with the actual vehicle have been performed in a test tank and diving pool. During these experiments, thrusters responsible for yaw motion are driven by sinusoidal voltage signal profiles. An assessment of the feasibility of the method reveals that estimated dynamic system models are more reliable when considering slow and small sinusoidal voltage signal profiles, i.e. with larger periods and with relatively small amplitude and offset.

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Stable carbon isotopic fractionation during calcium carbonate precipitation induced by urease-catalysed hydrolysis of urea was experimentally investigated in artificial water at a constant temperature of 30 degrees C. Carbon isotope fractionation during urea hydrolysis follows a Rayleigh distillation trend characterized by a C-13-enrichment factor of -20 to -22 parts per thousand. CaCO3 precipitate is up to 17.9 parts per thousand C-13-depleted relative to the urea substrate (-48.9 +/- 0.07 parts per thousand). Initial CaCO3 precipitate forms close to isotopic equilibrium with dissolved inorganic carbon. Subsequent precipitation occurs at -2 to -3 parts per thousand offset from isotopic equilibrium, suggesting that the initial delta C-13 value of CaCO3 is reset through dissolution followed by reprecipitation with urease molecules playing a role in offsetting the delta C-13 value of CaCO3 from isotopic equilibrium. Potentially, this isotopic systematics may provide a tool for the diagnosis of ureolytically-formed carbonate cements used as sealing agent. Moreover, it may serve as a basis to develop a carbon isotope tool for the quantification of ureolytically-induced CO2 sequestration. Finally, it suggests carbon isotope disequilibrium as a hallmark of past enzymatic activity in ancient microbial carbonate formation. (C) 2012 Elsevier B.V. All rights reserved.

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Chlortalidone (CTD) is an antihypertensive drug for which only two solid state phases have been structurally elucidated thus far. Here, we have prepared a chloroform solvate thereof, namely, CTD Form IV, and its structure was compared to those of Form I and Form III. Its two conformers exhibit a dual structural feature in relation to the antecedent polymorphs. Both CTD molecules of Form IV adopt a Form III-like conformation, which is featured, if the conformation of CTD Form I is used as a reference, by a rotation of about 90 degrees on the axis of the C-C bond bridging the substituted benzene and isoindolinyl rings. However, CTD Form IV assembles as in the Form I crystal packing despite the different stacking fashion of their centrosymmetric dimers. In contrast to Form I, there is no offset stacking in Form IV, which forces a bend of ca. 24 degrees between the planes passing through the isoindolinyl moieties of two [100]-stacked dimers. Chloroform molecules at a maximum stoichiometry of 0.25 mol per mol of the drug play a stabilizing role in the assembly of Form IV by filling the channels formed on the crystals.

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Solar infrared colors provide powerful constraints on the stellar effective temperature scale, but they must be measured with both accuracy and precision in order to do so. We fulfill this requirement by using line-depth ratios to derive in a model-independent way the infrared colors of the Sun, and we use the latter to test the zero point of the Casagrande et al. effective temperature scale, confirming its accuracy. Solar colors in the widely used Two Micron All Sky Survey (2MASS) JHK(s) and WISE W1-4 systems are provided: (V - J)(circle dot) = 1.198, (V - H)(circle dot) = 1.484, (V - K-s)(circle dot) = 1.560, (J - H)(circle dot) = 0.286, (J - K-s)(circle dot) = 0.362, (H - K-s)(circle dot) = 0.076, (V - W1)(circle dot) = 1.608, (V - W2)(circle dot) = 1.563, (V - W3)(circle dot) = 1.552, and (V - W4)(circle dot) = 1.604. A cross-check of the effective temperatures derived implementing 2MASS or WISE magnitudes in the infrared flux method confirms that the absolute calibration of the two systems agrees within the errors, possibly suggesting a 1% offset between the two, thus validating extant near-and mid-infrared absolute calibrations. While 2MASS magnitudes are usually well suited to derive T-eff, we find that a number of bright, solar-like stars exhibit anomalous WISE colors. In most cases, this effect is spurious and can be attributed to lower-quality measurements, although for a couple of objects (3%+/- 2% of the total sample) it might be real, and may hint at the presence of warm/hot debris disks.

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Access to electricity, granting relative independence of human activity on the dark phase of the day, has been pointed out as an important cause for the absence of seasonal changes in the daily rhythms of humans living in urban areas. Featuring a population of adult Guarani natives living without access to electricity, the present naturalistic study was designed to explore possible effects of different natural photoperiods and temperature on human circadian rhythms. We compared time series of wrist temperature (WT) and motor activity in winter and summer, respectively, 01 24 individuals aged 18 to 80. Twenty-four-hour rhythms of WT showed lower amplitudes and higher mean levels in summer, with no significant seasonal differences in acrophase. In contrast, rest-activity (RA) rhythms exhibited a significantly later rest on-and offset in summer, but no seasonal changes in duration, amplitude and mean level. We furthermore identified a phase advance of both the WT acrophase and rest onset with increasing age of the individuals. We concluded that in our study the effect of different seasons was reflected in the amplitude and mean level of the WT rhythm, as well the onset of nighttime rest, which was delayed in summer. (C) 2011 Elsevier Inc. All rights reserved.

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Preformed structural reinforcements have shown good performance in crash tests, where the great advantage is their weight. These reinforcements are designed with the aim of increasing the rigidity of regions with large deformations, thus stabilising sections of the vehicle that work as load path during impact. The objective of this work is to show the application of structural reinforcements made of polymeric material PA66 in the field of vehicle safety, through finite element simulations. Simulations of frontal impact at 50 km/h and in ODB (offset deformable barrier) at 57 km/h configurations (standards such as ECE R-94 and ECE R-12) were performed in the software LS-DYNA R (R) and MADYMO (R). The simulations showed that the use of polymeric reinforcements leads to a 70% reduction in A-pillar intrusion, a 65% reduction in the displacement of the steering column and a 59% reduction in the deformation in the region of the occupant legs and feet. The level of occupant injuries was analysed by MADYMO (R) software, and a reduction of 23.5% in the chest compression and 80% in the tibia compression were verified. According to the standard, such conditions lead to an improvement in the occupant safety in a vehicle collision event.