799 resultados para Skepticism toward advertising
Resumo:
This paper uses a survey experiment to examine differences in public attitudes toward 'direct' and 'indirect' government spending. Federal social welfare spending in the USA has two components: the federal government spends money to directly provide social benefits to citizens, and also indirectly subsidizes the private provision of social benefits through tax expenditures. Though benefits provided through tax expenditures are considered spending for budgetary purposes, they differ from direct spending in several ways: in the mechanisms through which benefits are delivered to citizens, in how they distribute wealth across the income spectrum, and in the visibility of their policy consequences to the mass public. We develop and test a model explaining how these differences will affect public attitudes toward spending conducted through direct and indirect means. We find that support for otherwise identical social programs is generally higher when such programs are portrayed as being delivered through tax expenditures than when they are portrayed as being delivered by direct spending. In addition, support for tax expenditure programs which redistribute wealth upward drops when citizens are provided information about the redistributive effects. Both of these results are conditioned by partisanship, with the opinions of Republicans more sensitive to the mechanism through which benefits are delivered, and the opinions of Democrats more sensitive to information about their redistributive effects.
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This project aimed to evaluate young people's attitudes towards drugs and to draft preventive strategies for use among young people at school and during military service. Three target groups were surveyed: young heroin users in Sofia, drug users undergoing treatment in the Military Medical Academy, and male students between the ages of 16 and 18. The research showed that more than half the respondents had used heroin for the first time before they were 16 and 11% tried it first at the age of 13, the lowest age registered since drug use in Bulgaria has been studied. One in five male students aged 16 to 18 has used hashish or marijuana at least once and amphetamines and non-prescription medications are the second-choice drugs for Bulgarian school pupils. The best predictors of drug use among young people are drug use among friends, early alcohol and tobacco use, perceived availability of drugs, an underrating of the health hazards of drug use and a lack of proper information about these, willingness to take drugs, where and with whom the young people have grown up, and a sensation-seeking attitude.
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[1] The Bern3D model was applied to quantify the mechanisms of carbon cycle changes during the Holocene (last 11,000 years). We rely on scenarios from the literature to prescribe the evolution of shallow water carbonate deposition and of land carbon inventory changes over the glacial termination (18,000 to 11,000 years ago) and the Holocene and modify these scenarios within uncertainties. Model results are consistent with Holocene records of atmospheric CO2 and δ13C as well as the spatiotemporal evolution of δ13C and carbonate ion concentration in the deep sea. Deposition of shallow water carbonate, carbonate compensation of land uptake during the glacial termination, land carbon uptake and release during the Holocene, and the response of the ocean-sediment system to marine changes during the termination contribute roughly equally to the reconstructed late Holocene pCO2 rise of 20 ppmv. The 5 ppmv early Holocene pCO2 decrease reflects terrestrial uptake largely compensated by carbonate deposition and ocean sediment responses. Additional small contributions arise from Holocene changes in sea surface temperature, ocean circulation, and export productivity. The Holocene pCO2 variations result from the subtle balance of forcings and processes acting on different timescales and partly in opposite direction as well as from memory effects associated with changes occurring during the termination. Different interglacial periods with different forcing histories are thus expected to yield different pCO2 evolutions as documented by ice cores.
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Peña, Bensimon, and Colyar (2006) noted: “Not only do African Americans, Hispanics, and Native Americans have lower graduation rates than [do] Whites and Asian Americans, they also experience inequalities in just about every indicator of academic success – from earned grade point average to placement on the dean’s list to graduation rates in competitive majors” (p. 48). While these and other racialized outcomes disparities cannot be attributed to a narrow set of explanatory factors, one thing is known for sure: College students who are actively engaged inside and outside the classroom are considerably more likely than are their disengaged peers to persist through baccalaureate degree attainment. Furthermore, engaged students typically accrue the desired outcomes that are central to liberal education. This is especially true for engagement in what Kuh (2008) refers to as “high-impact” educational experiences – study abroad programs, learning communities, undergraduate research programs, service learning opportunities, and summer internships, to name a few. Unfortunately, racial minority undergraduates are considerably less likely than are their White peers to enjoy the educational benefits associated with these experiences.
Resumo:
A series of Gly-neurotensin(8-13) analogues modified at the N-terminus by acyclic tetraamines (Demotensin 1-4) were obtained by solid-phase peptide synthesis techniques. Strategic replacement of amino acids and/or reduction of sensitive peptide bonds were performed to enhance conjugate resistance against proteolytic enzymes. During 99mTc-labeling, single species radiopeptides, [99mTc]Demotensin 1-4, were easily obtained in high yields and typical specific activities of 1 Ci/micromol. Peptide conjugates displayed a high affinity binding to the human neurotensin subtype 1 receptor (NTS1-R) expressed in colon adenocarcinoma HT-29 or WiDr cells and/or in human tumor sections. [99mTc]Demotensin 1-4 internalized very rapidly in HT-29 or WiDr cells by a NTS1-R-mediated process. [99mTc]Demotensin 3 and 4, which remained stable during 1 h incubation in murine plasma, were selectively studied in nude mice bearing human HT-29 and WiDr xenografts. After injection, [99mTc]Demotensin 3 and 4 effectively and specifically localized in the experimental tumors and were rapidly excreted via the kidneys into the urine, exhibiting overall biodistribution patterns favorable for NTS1-R-targeted tumor imaging in man.
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OBJECTIVE(S): Even though the mechanism is not clearly understood, direct intramyocardial cell transplantation has demonstrated potential to treat patients with severe heart failure. We previously reported on the bioengineering of myoblast-based constructs. We investigate here the functional outcome of infarcted hearts treated by implantation of myoblast-seeded scaffolds. METHODS: Adult Lewis rats with echocardiography-confirmed postinfarction reduced ejection fraction (48.3% +/- 1.1%) were randomized to (1) implantation of myoblast-seeded polyurethane patches at the site of infarction (PU-MyoB, n = 11), (2) implantation of nonseeded polyurethane patches (PU, n = 11), (3) sham operation (Sham, n = 12), and (4) direct intramyocardial myoblast injection (MyoB, n = 11). Four weeks later, the functional assessment by echocardiography was repeated, and we additionally performed left ventricular catheterization plus histologic studies. RESULTS: The ejection fraction significantly decreased in the PU (39.1% +/- 2.3%; P = .02) and Sham (39.9% +/- 3.5%; P = .04) groups, whereas it remained stable in the PU-MyoB (48.4% +/- 3.1%) and MyoB (47.9% +/- 3.0%) groups during the observation time. Similarly, left ventricular contractility was significantly higher in groups PU-MyoB (4960 +/- 266 mm Hg/s) and MyoB (4748 +/- 304 mm Hg/s) than in groups PU (3909 +/- 248 mm Hg/s, P = .01) and Sham (4028 +/- 199 mm Hg/s, P = .01). Immunohistology identified a high density of myoblasts within the seeded scaffolds without any migration toward the host cardiac tissue and no evidence of cardiac cell differentiation. CONCLUSIONS: Myoblast-seeded polyurethane scaffolds prevent post-myocardial infarction progression toward heart failure as efficiently as direct intramyocardial injection. The immunohistologic analysis suggests that an indirect mechanism, potentially a paracrine effect, may be assumed.
Resumo:
BACKGROUND: The Anesthetic Conserving Device (AnaConDa) uncouples delivery of a volatile anesthetic (VA) from fresh gas flow (FGF) using a continuous infusion of liquid volatile into a modified heat-moisture exchanger capable of adsorbing VA during expiration and releasing adsorbed VA during inspiration. It combines the simplicity and responsiveness of high FGF with low agent expenditures. We performed in vitro characterization of the device before developing a population pharmacokinetic model for sevoflurane administration with the AnaConDa, and retrospectively testing its performance (internal validation). MATERIALS AND METHODS: Eighteen females and 20 males, aged 31-87, BMI 20-38, were included. The end-tidal concentrations were varied and recorded together with the VA infusion rates into the device, ventilation and demographic data. The concentration-time course of sevoflurane was described using linear differential equations, and the most suitable structural model and typical parameter values were identified. The individual pharmacokinetic parameters were obtained and tested for covariate relationships. Prediction errors were calculated. RESULTS: In vitro studies assessed the contribution of the device to the pharmacokinetic model. In vivo, the sevoflurane concentration-time courses on the patient side of the AnaConDa were adequately described with a two-compartment model. The population median absolute prediction error was 27% (interquartile range 13-45%). CONCLUSION: The predictive performance of the two-compartment model was similar to that of models accepted for TCI administration of intravenous anesthetics, supporting open-loop administration of sevoflurane with the AnaConDa. Further studies will focus on prospective testing and external validation of the model implemented in a target-controlled infusion device.