203 research outputs found

    Road Safety Valuation under a Stated Choice Framework

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    The value of fatal risk reductions is a vital input for road safety cost-benefit analysis. It has been traditionally estimated by means of contingent valuation in spite of growing criticism surrounding this approach. Furthermore, many believe that risk-money trade-offs are not well understood due to the difficulty in internalizing tiny risks. We have succeeded in applying the Stated Choice (SC) approach to tackle this problem, using as one of the attributes the number of accidents with fatal victims (i.e. a proxy for risk). To assess the robustness of SC, we conducted an external validity test based on results for three different studies. We investigated if preferences were well defined according to economic theory (i.e. as initial risk increases, the marginal willingness-to-pay should be higher). We also addressed the generally ignored issue of whether there should be a unique value of fatal risk reductions. We found that people can internalize risk consistently from an economic viewpoint, and that although each sample yields different values of risk reductions, there was a relationship between the risk level and the value of risk reductions in each context examined; this evidence could be most helpful within the context of developing countries. Finally, we offer an hypothesis to explain the differences between our values with those obtained in industrialised countries, highlighting the importance of doing local studies rather than transferring imported values

    Influence of survey engagement and multiple-choice heuristics in the estimation of the value of a statistical life

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    Estimating the value of non-market goods, such as reductions in mortality risks due to traffic accidents or air pollution, is typically done using stated choice (SC) data. However, issues with potential estimation biases due to the hypothetical nature of SC experiments arise, as protest choices are common and survey engagement is not constant across respondents. Further, if respondents choose to use different choice mechanisms and this is not considered, the results may also be biased. We designed an SC experiment to estimate the willingness to pay (WTP) for mortality risk reductions, that allowed us to simultaneously estimate the WTP to reduce the risk of traffic accident deaths and cardiorespiratory deaths due to air pollution. We formulated and estimated a multiple heuristic latent class model that also considered two latent constructs: Institutional Belief, to consider protest responses, and survey Engagement as a class membership covariate. We found, first, that individuals with lower institutional belief gave a higher probability of choice to the status-quo alternative, shying away from programs involving governmental action. Second, that not identifying respondents who do not appropriately engage in the experiment, biased the WTP estimators. In our case WTP decreased up to 26% when two different choice heuristics were allowed for in the model. © 202

    Estimating the willingness-to-pay and value of risk reduction for car occupants in the road environment

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    In recent years there has been a re-focus on the valuation of a statistical life (VSL) from the ex post or human capital method to an ex ante willingness to pay approach. This is in part a recognition that we may have been undervaluing the cost of fatalities and injuries to society associated with crashes, but also a strong belief in the need to focus on establishing the amount, ex ante, that individuals are willing to pay to reduce the risk of exposure to circumstances that might lead to death or degree of injury on the road network. This study has developed a framework in which to identify the heterogeneity in willingness to pay (WTP) by individuals who are drivers or passengers in cars to avoid being killed or injured. A stated choice experiment approach is developed. The empirical setting is a choice of route for a particular trip that a sample of individuals periodically undertakes in Australia. The particular trip is described in enough detail to provide the respondent with a familiar market environment, providing all the relevant background information required for making a decision. Mixed logit models are estimated to obtain the marginal (dis)utilities associated with each influence on the choice amongst the attribute packages offered in the stated choice scenarios. These estimates are used to obtain the WTP distributions for fatality and injury avoidance, which are then aggregated to obtain estimates of the value of risk reduction (VRR), often referred to generically as the value of a statistical life

    Epigenetic Transcriptional Regulation of the Growth Arrest-Specific gene 1 (Gas1) in Hepatic Cell Proliferation at Mononucleosomal Resolution

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    BACKGROUND: Gas1 (growth arrest-specific 1) gene is known to inhibit cell proliferation in a variety of models, but its possible implication in regulating quiescence in adult tissues has not been examined to date. The knowledge of how Gas1 is regulated in quiescence may contribute to understand the deregulation occurring in neoplastic diseases. METHODOLOGY/PRINCIPAL FINDINGS: Gas1 expression has been studied in quiescent murine liver and during the naturally synchronized cell proliferation after partial hepatectomy. Chromatin immunoprecipitation at nucleosomal resolution (Nuc-ChIP) has been used to carry out the study preserving the in vivo conditions. Transcription has been assessed at real time by quantifying the presence of RNA polymerase II in coding regions (RNApol-ChIP). It has been found that Gas1 is expressed not only in quiescent liver but also at the cell cycle G(1)/S transition. The latter expression peak had not been previously reported. Two nucleosomes, flanking a nucleosome-free region, are positioned close to the transcription start site. Both nucleosomes slide in going from the active to the inactive state and vice versa. Nuc-ChIP analysis of the acquisition of histone epigenetic marks show distinctive features in both active states: H3K9ac and H3K4me2 are characteristic of transcription in G(0) and H4R3me2 in G(1)/S transition. Sequential-ChIP analysis revealed that the "repressing" mark H3K9me2 colocalize with several "activating" marks at nucleosome N-1 when Gas1 is actively transcribed suggesting a greater plasticity of epigenetic marks than proposed until now. The recruitment of chromatin-remodeling or modifying complexes also displayed distinct characteristics in quiescence and the G(1)/S transition. CONCLUSIONS/SIGNIFICANCE: The finding that Gas1 is transcribed at the G(1)/S transition suggests that the gene may exert a novel function during cell proliferation. Transcription of this gene is modulated by specific "activating" and "repressing" epigenetic marks, and by chromatin remodeling and histone modifying complexes recruitment, at specific nucleosomes in Gas1 promoter

    Enfermedad Mínima Residual (EMR) en Leucemia Linfoblåstica Aguda pediåtrica (LLA). Estudio multicéntrico

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    En las Ășltimas 4 dĂ©cadas se profundizĂł el conocimiento en la cinĂ©tica de la respuesta temprana al tratamiento en pacientes con Leucemia LinfoblĂĄstica Aguda (LLA) para predecir riesgo de recaĂ­da1. Sin embargo, 20% de los pacientes que inicialmente responden al tratamiento y morfolĂłgicamente no presentan blastos en mĂ©dula Ăłsea, recidivan durante el tratamiento o luego de la finalizar el mismo.Fil: Soria, Rose Mari. Hospital de Niños Dr. Ricardo GutiĂ©rrez; Argentina.Fil: Agriello, Evangelina. Laboratorio de Especialidades BioquĂ­micas; Argentina.Fil: Agriello, Evangelina. Hospital Interzonal General Dr. JosĂ© Penna; Argentina.Fil: Agriello, Evangelina. Grupo Argentino de Tratamiento de la Leucemia Aguda; Argentina.Fil: Gutierrez, MarĂ­a. Hospital de Niños Dr. Ricardo GutiĂ©rrez; Argentina.Fil: Gil, Gimena. Hospital de Niños Dr. Ricardo GutiĂ©rrez; Argentina.Fil: Iommi, MarĂ­a Paula. Laboratorio de Especialidades BioquĂ­micas; Argentina.Fil: Torreguitart, Federico AndrĂ©s. Laboratorio de Especialidades BioquĂ­micas; Argentina.Fil: Caferri, Horacio. Hospital Interzonal General Dr. JosĂ© Penna; Argentina.Fil: CĂ©dola, Alejandra. Sanatorio San Lucas; Argentina.Fil: Majek, Elena. Hospital de Niños Dr. HĂ©ctor Quintana; Argentina.Fil: Hiramatsu, Elizabeth. Hospital PediĂĄtrico del Niño JesĂșs; Argentina.Fil: Morell, Daniela. Hospital PediĂĄtrico del Niño JesĂșs; Argentina.Fil: Rizzi, MarĂ­a Laura. Sanatorio Allende; Argentina.Fil: RodrĂ­guez Cuimbra, Silvia. Hospital PediĂĄtrico Juan Pablo II; Argentina.Fil: Gomel De Baraja, MarĂ­a E. Hospital PediĂĄtrico Juan Pablo II; Argentina.Fil: Cabral Castella, Antonia C. Hospital PediĂĄtrico Juan Pablo II; Argentina.Fil: Pistaccio, Luis. Hospital Interzonal de Agudos Especializado en PediatrĂ­a Sor MarĂ­a Ludovica; Argentina.Fil: Schuttemberg, Virginia. Hospital Interzonal de Agudos Especializado en PediatrĂ­a Sor MarĂ­a Ludovica; Argentina.Fil: Riccieri, Cecilia.Fil: Solari, Liliana. Hospital Nacional Profesor Alejandro Posadas; Argentina.Fil: Solari, Liliana. Grupo Argentino de Tratamiento de la Leucemia Aguda; Argentina.Fil: Riccieri, Cecilia. Hospital Nacional Profesor Alejandro Posadas; Argentina.Fil: Gaillard, MarĂ­a I. Hospital de Niños Dr. Ricardo GutiĂ©rrez; Argentina.Fil: Gaillard, MarĂ­a I. Grupo Argentino de Tratamiento de la Leucemia Aguda; Argentina.Fil: Ferraro, C. Hospital de Niños Dr. Ricardo GutiĂ©rrez; Argentina.Fil: HernĂĄndez, M. ClĂ­nica Dr. Matera; Argentina.Fil: Drosovsky, C. Sanatorio San Lucas; Argentina.HematologĂ­

    The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

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    AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

    MUSiC : a model-unspecific search for new physics in proton-proton collisions at root s=13TeV

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    Results of the Model Unspecific Search in CMS (MUSiC), using proton-proton collision data recorded at the LHC at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1), are presented. The MUSiC analysis searches for anomalies that could be signatures of physics beyond the standard model. The analysis is based on the comparison of observed data with the standard model prediction, as determined from simulation, in several hundred final states and multiple kinematic distributions. Events containing at least one electron or muon are classified based on their final state topology, and an automated search algorithm surveys the observed data for deviations from the prediction. The sensitivity of the search is validated using multiple methods. No significant deviations from the predictions have been observed. For a wide range of final state topologies, agreement is found between the data and the standard model simulation. This analysis complements dedicated search analyses by significantly expanding the range of final states covered using a model independent approach with the largest data set to date to probe phase space regions beyond the reach of previous general searches.Peer reviewe

    Measurement of prompt open-charm production cross sections in proton-proton collisions at root s=13 TeV

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    The production cross sections for prompt open-charm mesons in proton-proton collisions at a center-of-mass energy of 13TeV are reported. The measurement is performed using a data sample collected by the CMS experiment corresponding to an integrated luminosity of 29 nb(-1). The differential production cross sections of the D*(+/-), D-+/-, and D-0 ((D) over bar (0)) mesons are presented in ranges of transverse momentum and pseudorapidity 4 < p(T) < 100 GeV and vertical bar eta vertical bar < 2.1, respectively. The results are compared to several theoretical calculations and to previous measurements.Peer reviewe

    Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at root s=13 TeV

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    A search is presented for new particles produced at the LHC in proton-proton collisions at root s = 13 TeV, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb(-1), collected in 2017-2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb(-1), collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.Peer reviewe

    Development and validation of HERWIG 7 tunes from CMS underlying-event measurements

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    This paper presents new sets of parameters (“tunes”) for the underlying-event model of the HERWIG7 event generator. These parameters control the description of multiple-parton interactions (MPI) and colour reconnection in HERWIG7, and are obtained from a fit to minimum-bias data collected by the CMS experiment at s=0.9, 7, and 13Te. The tunes are based on the NNPDF 3.1 next-to-next-to-leading-order parton distribution function (PDF) set for the parton shower, and either a leading-order or next-to-next-to-leading-order PDF set for the simulation of MPI and the beam remnants. Predictions utilizing the tunes are produced for event shape observables in electron-positron collisions, and for minimum-bias, inclusive jet, top quark pair, and Z and W boson events in proton-proton collisions, and are compared with data. Each of the new tunes describes the data at a reasonable level, and the tunes using a leading-order PDF for the simulation of MPI provide the best description of the dat
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