eli parra - Academia.edu (original) (raw)

Papers by eli parra

Cognitive Affective & Behavioral Neuroscience, 2011

Recognition memory was examined for visual affective stimuli using behavioral and event-related b... more Recognition memory was examined for visual affective stimuli using behavioral and event-related brain potential (ERP) measures. Images from the International Affective Picture System (IAPS) that varied systematically in arousal level (low, high) and valence direction (unpleasant, pleasant) were first viewed passively. Then, during a response phase, the original images were intermixed with an equal number of new images and presented, and participants were instructed to press a button to indicate whether each stimulus picture was previously viewed (target) or new (foil). Participants were more sensitive to unpleasant- than to pleasant-valence stimuli and were biased to respond to high-arousal unpleasant stimuli as targets, whether the stimuli were previously viewed or new. Response times (RTs) to target stimuli were systematically affected by valence, whereas RTs to foil stimuli were influenced by arousal level. ERP component amplitudes were generally larger for high than for low arousal levels. The P300 (late positive component) amplitude was largest for high-arousal unpleasant target images. These and other amplitude effects suggest that high-arousal unpleasant stimuli engage a privileged memory-processing route during stimulus processing. Theoretical relationships between affective and memory processes are discussed.

A search is presented for production of a heavy up-type quark (t ′ ) together with its antipartic... more A search is presented for production of a heavy up-type quark (t ′ ) together with its antiparticle, assuming subsequent decay to a W boson and a b quark, t ′t ′ → W + bW −b . The search is based on 1.04 fb −1 of proton-proton collisions at √ s = 7 TeV collected by the ATLAS detector at the CERN Large Hadron Collider. Data are analyzed in the lepton+jets final state, characterized by a high transverse momentum isolated electron or muon, high missing transverse momentum and at least three jets. No significant excess of events above the background expectation is observed. A 95% C.L. lower limit of 404 GeV is set for the mass of the t ′ quark.

PLOS Medicine, 2009

The Policy Forum allows health policy makers around the world to discuss challenges and opportuni... more The Policy Forum allows health policy makers around the world to discuss challenges and opportunities for improving health care in their societies.

Bulletin of Spanish Studies, 2011

Journal of Human Genetics, 2008

A sample of central Argentina (Córdoba) was genotyped for the first hypervariable region (HVS-I) ... more A sample of central Argentina (Córdoba) was genotyped for the first hypervariable region (HVS-I) plus a set of coding region mitochondrial DNA (mtDNA) single nucleotide polymorphisms (SNPs) (N = 102) and compared with a data set of Y-chromosome short tandem repeats (Y-STRs; N = 100) previously genotyped in the same individuals. We additionally compiled a database containing more than 4,000, 6,800, and 12,000 HVS-I sequences of Native American, sub-Saharan African, and European origin, respectively. The Y-Chromosome Haplotype Reference Database (YHRD) was used as a reference for the Y-STR profiles from Córdoba. The Native American component is highly prevalent on the maternal side (~41%) in contrast to the Y-chromosome paternal contribution (~2%), indicating a strong gender bias in the colonization and admixture processes that occurred in the recent history of Argentina, in agreement with historical records. The demographic input of African slaves in Córdoba was very high in the eighteenth century (~40% of the total population) but decreased dramatically after a few decades; therefore, the minor traces of sub-Saharan Y-chromosome and mtDNA lineages observed in our sample fit well with these historical records. The European Y-chromosome component of Córdoba (~97%; in contrast to the 57% observed in the mtDNA side) also mirrors the substantial immigration experienced by Argentina during the beginning of the last century, predominantly from Italy and Spain.

Proceedings of The National Academy of Sciences, 2011

The science and management of infectious disease are entering a new stage. Increasingly public po... more The science and management of infectious disease are entering a new stage. Increasingly public policy to manage epidemics focuses on motivating people, through social distancing policies, to alter their behavior to reduce contacts and reduce public disease risk. Person-to-person contacts drive human disease dynamics. People value such contacts and are willing to accept some disease risk to gain contact-related benefits. The cost-benefit trade-offs that shape contact behavior, and hence the course of epidemics, are often only implicitly incorporated in epidemiological models. This approach creates difficulty in parsing out the effects of adaptive behavior. We use an epidemiological-economic model of disease dynamics to explicitly model the trade-offs that drive person-toperson contact decisions. Results indicate that including adaptive human behavior significantly changes the predicted course of epidemics and that this inclusion has implications for parameter estimation and interpretation and for the development of social distancing policies. Acknowledging adaptive behavior requires a shift in thinking about epidemiological processes and parameters.

This Letter presents the results of a direct search with the ATLAS detector at the LHC for a Stan... more This Letter presents the results of a direct search with the ATLAS detector at the LHC for a Standard Model Higgs boson of mass 110 ≤ m H ≤ 130 GeV produced in association with a W or Z boson and decaying to bb. Three decay channels are considered: ZH → ℓ + ℓ − bb, W H → ℓνbb and ZH → ννbb, where ℓ corresponds to an electron or a muon. No evidence for Higgs boson production is observed in a dataset of 7 TeV pp collisions corresponding to 4.7 fb −1 of integrated luminosity collected by ATLAS in 2011. Exclusion limits on Higgs boson production, at the 95% confidence level, of 2.5 to 5.5 times the Standard Model cross section are obtained in the mass range 110-130 GeV. The expected exclusion limits range between 2.5 and 4.9 for the same mass interval.

√ s = 7 TeV using final states with an electron or a muon and a hadronically decaying τ lepton

This paper is dedicated to the memory of our ATLAS colleagues who did not live to see the full im... more This paper is dedicated to the memory of our ATLAS colleagues who did not live to see the full impact and significance of their contributions to the experiment.

A search for direct pair production of supersymmetric top squarks (t 1 ) is presented, assuming t... more A search for direct pair production of supersymmetric top squarks (t 1 ) is presented, assuming thet 1 decays into a top quark and the lightest supersymmetric particle,χ 0 1, and that both top quarks decay to purely hadronic final states. A total of 16 (4) events are observed compared to a predicted Standard Model background of 13.5 + 3.7 − 3.6 (4.4 + 1.7 − 1.3 ) events in two signal regions based on L dt = 4.7 fb −1 of pp collision data taken at √ s = 7 TeV with the ATLAS detector at the LHC. An exclusion region in thet 1 versusχ 0 1 mass plane is evaluated: 370 < mt 1 < 465 GeV is excluded for mχ0 1 ∼ 0 GeV while mt 1 = 445 GeV is excluded for mχ0 1 ≤ 50 GeV. Technology, Ankara; (e)

Physics Letters B, 2012

A search for diphoton events with large missing transverse momentum has been performed using prot... more A search for diphoton events with large missing transverse momentum has been performed using proton-proton collision data at √ s = 7 TeV recorded with the ATLAS detector, corresponding to an integrated luminosity of 4.8 fb −1 . No excess of events was observed above the Standard Model prediction and model-dependent 95 % confidence level exclusion limits are set. In the context of a generalised model of gauge-mediated supersymmetry breaking with a bino-like lightest neutralino of mass above 50 GeV, gluinos (squarks) below 1.07 TeV (0.87 TeV) are excluded, while a breaking scale Λ below 196 TeV is excluded for a minimal model of gauge-mediated supersymmetry breaking. For a specific model with one universal extra dimension, compactification scales 1/R < 1.40 TeV are excluded. These limits provide the most stringent tests of these models to date.

Cognitive Affective & Behavioral Neuroscience, 2011

Recognition memory was examined for visual affective stimuli using behavioral and event-related b... more Recognition memory was examined for visual affective stimuli using behavioral and event-related brain potential (ERP) measures. Images from the International Affective Picture System (IAPS) that varied systematically in arousal level (low, high) and valence direction (unpleasant, pleasant) were first viewed passively. Then, during a response phase, the original images were intermixed with an equal number of new images and presented, and participants were instructed to press a button to indicate whether each stimulus picture was previously viewed (target) or new (foil). Participants were more sensitive to unpleasant- than to pleasant-valence stimuli and were biased to respond to high-arousal unpleasant stimuli as targets, whether the stimuli were previously viewed or new. Response times (RTs) to target stimuli were systematically affected by valence, whereas RTs to foil stimuli were influenced by arousal level. ERP component amplitudes were generally larger for high than for low arousal levels. The P300 (late positive component) amplitude was largest for high-arousal unpleasant target images. These and other amplitude effects suggest that high-arousal unpleasant stimuli engage a privileged memory-processing route during stimulus processing. Theoretical relationships between affective and memory processes are discussed.

A search is presented for production of a heavy up-type quark (t ′ ) together with its antipartic... more A search is presented for production of a heavy up-type quark (t ′ ) together with its antiparticle, assuming subsequent decay to a W boson and a b quark, t ′t ′ → W + bW −b . The search is based on 1.04 fb −1 of proton-proton collisions at √ s = 7 TeV collected by the ATLAS detector at the CERN Large Hadron Collider. Data are analyzed in the lepton+jets final state, characterized by a high transverse momentum isolated electron or muon, high missing transverse momentum and at least three jets. No significant excess of events above the background expectation is observed. A 95% C.L. lower limit of 404 GeV is set for the mass of the t ′ quark.

PLOS Medicine, 2009

The Policy Forum allows health policy makers around the world to discuss challenges and opportuni... more The Policy Forum allows health policy makers around the world to discuss challenges and opportunities for improving health care in their societies.

Bulletin of Spanish Studies, 2011

Journal of Human Genetics, 2008

A sample of central Argentina (Córdoba) was genotyped for the first hypervariable region (HVS-I) ... more A sample of central Argentina (Córdoba) was genotyped for the first hypervariable region (HVS-I) plus a set of coding region mitochondrial DNA (mtDNA) single nucleotide polymorphisms (SNPs) (N = 102) and compared with a data set of Y-chromosome short tandem repeats (Y-STRs; N = 100) previously genotyped in the same individuals. We additionally compiled a database containing more than 4,000, 6,800, and 12,000 HVS-I sequences of Native American, sub-Saharan African, and European origin, respectively. The Y-Chromosome Haplotype Reference Database (YHRD) was used as a reference for the Y-STR profiles from Córdoba. The Native American component is highly prevalent on the maternal side (~41%) in contrast to the Y-chromosome paternal contribution (~2%), indicating a strong gender bias in the colonization and admixture processes that occurred in the recent history of Argentina, in agreement with historical records. The demographic input of African slaves in Córdoba was very high in the eighteenth century (~40% of the total population) but decreased dramatically after a few decades; therefore, the minor traces of sub-Saharan Y-chromosome and mtDNA lineages observed in our sample fit well with these historical records. The European Y-chromosome component of Córdoba (~97%; in contrast to the 57% observed in the mtDNA side) also mirrors the substantial immigration experienced by Argentina during the beginning of the last century, predominantly from Italy and Spain.

Proceedings of The National Academy of Sciences, 2011

The science and management of infectious disease are entering a new stage. Increasingly public po... more The science and management of infectious disease are entering a new stage. Increasingly public policy to manage epidemics focuses on motivating people, through social distancing policies, to alter their behavior to reduce contacts and reduce public disease risk. Person-to-person contacts drive human disease dynamics. People value such contacts and are willing to accept some disease risk to gain contact-related benefits. The cost-benefit trade-offs that shape contact behavior, and hence the course of epidemics, are often only implicitly incorporated in epidemiological models. This approach creates difficulty in parsing out the effects of adaptive behavior. We use an epidemiological-economic model of disease dynamics to explicitly model the trade-offs that drive person-toperson contact decisions. Results indicate that including adaptive human behavior significantly changes the predicted course of epidemics and that this inclusion has implications for parameter estimation and interpretation and for the development of social distancing policies. Acknowledging adaptive behavior requires a shift in thinking about epidemiological processes and parameters.

This Letter presents the results of a direct search with the ATLAS detector at the LHC for a Stan... more This Letter presents the results of a direct search with the ATLAS detector at the LHC for a Standard Model Higgs boson of mass 110 ≤ m H ≤ 130 GeV produced in association with a W or Z boson and decaying to bb. Three decay channels are considered: ZH → ℓ + ℓ − bb, W H → ℓνbb and ZH → ννbb, where ℓ corresponds to an electron or a muon. No evidence for Higgs boson production is observed in a dataset of 7 TeV pp collisions corresponding to 4.7 fb −1 of integrated luminosity collected by ATLAS in 2011. Exclusion limits on Higgs boson production, at the 95% confidence level, of 2.5 to 5.5 times the Standard Model cross section are obtained in the mass range 110-130 GeV. The expected exclusion limits range between 2.5 and 4.9 for the same mass interval.

√ s = 7 TeV using final states with an electron or a muon and a hadronically decaying τ lepton

This paper is dedicated to the memory of our ATLAS colleagues who did not live to see the full im... more This paper is dedicated to the memory of our ATLAS colleagues who did not live to see the full impact and significance of their contributions to the experiment.

A search for direct pair production of supersymmetric top squarks (t 1 ) is presented, assuming t... more A search for direct pair production of supersymmetric top squarks (t 1 ) is presented, assuming thet 1 decays into a top quark and the lightest supersymmetric particle,χ 0 1, and that both top quarks decay to purely hadronic final states. A total of 16 (4) events are observed compared to a predicted Standard Model background of 13.5 + 3.7 − 3.6 (4.4 + 1.7 − 1.3 ) events in two signal regions based on L dt = 4.7 fb −1 of pp collision data taken at √ s = 7 TeV with the ATLAS detector at the LHC. An exclusion region in thet 1 versusχ 0 1 mass plane is evaluated: 370 < mt 1 < 465 GeV is excluded for mχ0 1 ∼ 0 GeV while mt 1 = 445 GeV is excluded for mχ0 1 ≤ 50 GeV. Technology, Ankara; (e)

Physics Letters B, 2012

A search for diphoton events with large missing transverse momentum has been performed using prot... more A search for diphoton events with large missing transverse momentum has been performed using proton-proton collision data at √ s = 7 TeV recorded with the ATLAS detector, corresponding to an integrated luminosity of 4.8 fb −1 . No excess of events was observed above the Standard Model prediction and model-dependent 95 % confidence level exclusion limits are set. In the context of a generalised model of gauge-mediated supersymmetry breaking with a bino-like lightest neutralino of mass above 50 GeV, gluinos (squarks) below 1.07 TeV (0.87 TeV) are excluded, while a breaking scale Λ below 196 TeV is excluded for a minimal model of gauge-mediated supersymmetry breaking. For a specific model with one universal extra dimension, compactification scales 1/R < 1.40 TeV are excluded. These limits provide the most stringent tests of these models to date.