281 research outputs found

    APEX: A Prime EXperiment at Jefferson Lab

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    APEX is an experiment at Thomas Jefferson National Accelerator Facility (JLab) in Virginia, USA, that searches for a new gauge boson (AA^\prime) with sub-GeV mass and coupling to ordinary matter of g(106102)eg^\prime \sim (10^{-6} - 10^{-2}) e. Electrons impinge upon a fixed target of high-Z material. An AA^\prime is produced via a process analogous to photon bremsstrahlung, decaying to an e+ee^+ e^- pair. A test run was held in July of 2010, covering mAm_{A^\prime} = 175 to 250 MeV and couplings g^\prime/e \; \textgreater \; 10^{-3}. A full run is approved and will cover mAm_{A^\prime} \sim 65 to 525 MeV and g^\prime/e \; \textgreater \; 2.3 \times10^{-4}.Comment: Contributed to the 8th Patras Workshop on Axions, WIMPs and WISPs, Chicago, July 18-22, 2012. 4 pages, 4 figure

    Search for a New Gauge Boson in Electron-Nucleus Fixed-Target Scattering by the APEX Experiment

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    We present a search at the Jefferson Laboratory for new forces mediated by sub-GeV vector bosons with weak coupling α′ to electrons. Such a particle A′ can be produced in electron-nucleus fixed-target scattering and then decay to an e+e- pair, producing a narrow resonance in the QED trident spectrum. Using APEX test run data, we searched in the mass range 175–250 MeV, found no evidence for an A′→e+e- reaction, and set an upper limit of α′/α≃10-6. Our findings demonstrate that fixed-target searches can explore a new, wide, and important range of masses and couplings for sub-GeV forces

    Measurement of the Neutron Radius of (208)Pb through Parity Violation in Electron Scattering

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    We report the first measurement of the parity-violating asymmetry APV in the elastic scattering of polarized electrons from 208Pb. APV is sensitive to the radius of the neutron distribution (Rn). The result APV=0.656±0.060(stat)±0.014(syst)  ppm corresponds to a difference between the radii of the neutron and proton distributions Rn-Rp=0.33-0.18+0.16  fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus

    Search for a new gauge boson in the AA' Experiment (APEX)

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    We present a search at Jefferson Laboratory for new forces mediated by sub-GeV vector bosons with weak coupling α\alpha' to electrons. Such a particle AA' can be produced in electron-nucleus fixed-target scattering and then decay to an e+ee^+e^- pair, producing a narrow resonance in the QED trident spectrum. Using APEX test run data, we searched in the mass range 175--250 MeV, found no evidence for an Ae+eA'\to e^+e^- reaction, and set an upper limit of α/α106\alpha'/\alpha \simeq 10^{-6}. Our findings demonstrate that fixed-target searches can explore a new, wide, and important range of masses and couplings for sub-GeV forces.Comment: 5 pages, 5 figures, references adde

    Prevalence of Adverse Childhood Experiences in the First Decade of Life: A Study in the Portuguese Cohort, Generation XXI

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    Adverse childhood experiences (ACEs) are a modifiable risk factor for diseases throughout life. This study estimates the prevalence of ACEs in children, addressing associated sociodemographic characteristics and examining the relationship of ACEs with the child’s health and behaviors. We used information on 5295 participants at 10 years old, of the birth cohort Generation XXI, established in Porto, Portugal. Children answered a self-administered questionnaire on ACEs, based on the original ACEs study. Principal component analysis was used to group correlated ACEs, and a score was computed to assess their cumulative effect. Overall, 96.2% of children reported having been exposed to at least one ACE. The most prevalent ACE was a household member shouting, yelling, or screaming at the child (57.7%). Boys were more likely than girls to report “abuse”, “school problems”, and “death/severe disease”. Low parental education, income, and unemployment were associated with an increased risk of “school problems”, “death/severe disease”, and “household dysfunction”. We observed that the dimensions of ACEs could be identified at 10 years of age. A disadvantaged socioeconomic environment was associated with dimensions of ACEs. These data illustrate the natural history of dimensions of ACEs and their potential social patterning.This work was supported by the European Regional Development Fund (ERDF) through the Operational Programme Competitiveness and Internationalization and national funding from the Foundation for Science and Technology (FCT), Portuguese Ministry of Science, Technology and Higher Education under the projects “BioAdversity: How childhood social adversity shapes health: The biology of social adversity” (POCI-01-0145-FEDER-016838; PTDC/DTP-EPI/1687/2014), “HIneC: When do health inequalities start? Understanding the impact of childhood social adversity on health trajectories from birth to early adolescence” (POCI-01-0145-FEDER-029567; PTDC/SAU-PUB/29567/2017) and “STEPACHE: The pediatric roots of amplified pain: from contextual influences to risk stratification” (POCI-01-0145-FEDER-029087; PTDC/SAU-EPI/29087/2017). It is also supported by the Unidade de Investigação em Epidemiologia—Instituto de Saúde Pública da Universidade do Porto (EPIUnit) (UIDB/04750/2020) and Laboratório para a Investigação Integrativa e Translacional em Saúde Populacional (ITR) (LA/P/0064/2020), Administração Regional de Saúde Norte (Regional Department of Ministry of Health) and Fundação Calouste Gulbenkian; PhD Grant SFRH/BD/144503/2019 (to AA) funded by FCT through Fundo Social Europeu (FSE) and CEECIND/01516/2017 (to SF)

    Measurement of the Neutron Radius of 208Pb Through Parity-Violation in Electron Scattering

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    We report the first measurement of the parity-violating asymmetry A_PV in the elastic scattering of polarized electrons from 208Pb. A_PV is sensitive to the radius of the neutron distribution (Rn). The result A_PV = 0.656 \pm 0.060 (stat) \pm 0.014 (syst) ppm corresponds to a difference between the radii of the neutron and proton distributions Rn - Rp = 0.33 +0.16 -0.18 fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus.Comment: 6 pages, 1 figur

    Adverse childhood experiences and bodily pain at 10 years of age: Findings from the Generation XXI cohort

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    Background: Youth and young adults with pain conditions report having a history of adverse childhood experiences (ACEs) more frequently than their healthy peers. The relationship between ACEs and pain before adolescence in population-based settings is not extensively researched. Objective: To examine the association between the history of ACEs and bodily pain at 10 years of age. Participants and setting: Cross-sectional analysis of 4738 participants of Generation XXI population-based birth cohort, recruited in 2005–06 in Porto, Portugal. Methods: Study includes self-reported data on ACEs exposures and bodily pain (pain presence, sites, and intensity a week prior to the interview). Adjusted odds ratios (AOR) and 95% confidence intervals (CI) were obtained from binary and multinomial logistic regression analyses to estimate the likelihood of various pain features according to the extent of exposure to ACEs (i.e., 0 ACEs, 1–3 ACEs, 4–5 ACEs, and ≥ 6 ACEs). Results: Prevalence of pain, multisite, and high-intensity pain a week prior to the interview increased with increasing exposure to ACEs. After controlling for sociodemographic characteristics, children who had experienced ≥6 ACEs were more likely to report pain [AOR 3.18 (95% CI 2.19, 4.74)], multisite pain [AOR 2.45 (95% CI 1.37, 4.40)], and high-intensity pain [AOR 4.27 (95% CI 2.56, 7.12)] compared with children with no ACEs. Conclusions: A dose-response association was observed between the cumulative number of ACEs and reports of pain in 10-year-old children, suggesting that embodiment of ACEs starts as early as childhood and that pain related to ACEs begins earlier than previously reported. © 2022 Elsevier LtdFunding text 1: This work was supported by the European Regional Development Fund (ERDF) through the Operational Programme Competitiveness and Internationalization and national funding from the Foundation for Science and Technology (FCT), Portuguese Ministry of Science, Technology and Higher Education under the projects “HIneC: When do health inequalities start? Understanding the impact of childhood social adversity on health trajectories from birth to early adolescence” ( POCI-01-0145-FEDER-029567 ; PTDC/SAU-PUB/29567/2017 ) and “STEPACHE: The pediatric roots of amplified pain: from contextual influences to risk stratification” ( POCI-01-0145-FEDER-029087 ; PTDC/SAU-EPI/29087/2017 ). It is also supported by Unidade de Investigação em Epidemiologia - Instituto de Saúde Pública da Universidade do Porto (EPIUnit) ( UIDB/04750/2020 ), Laboratório para a Investigação Integrativa e Translacional (ITR), Porto, Portugal ( LA/P/0064/2020 ), PhD Grant SFRH/BD/144503/2019 (to AA) funded by FCT through Fundo Social Europeu (FSE) and FCT Investigator contract CEECIND/01516/2017 (to SF). ; Funding text 2: This work was supported by the European Regional Development Fund (ERDF) through the Operational Programme Competitiveness and Internationalization and national funding from the Foundation for Science and Technology (FCT), Portuguese Ministry of Science, Technology and Higher Education under the projects “HIneC: When do health inequalities start? Understanding the impact of childhood social adversity on health trajectories from birth to early adolescence” (POCI-01-0145-FEDER-029567; PTDC/SAU-PUB/29567/2017) and “STEPACHE: The pediatric roots of amplified pain: from contextual influences to risk stratification” (POCI-01-0145-FEDER-029087; PTDC/SAU-EPI/29087/2017). It is also supported by Unidade de Investigação em Epidemiologia - Instituto de Saúde Pública da Universidade do Porto (EPIUnit) (UIDB/04750/2020), Laboratório para a Investigação Integrativa e Translacional (ITR), Porto, Portugal (LA/P/0064/2020), PhD Grant SFRH/BD/144503/2019 (to AA) funded by FCT through Fundo Social Europeu (FSE) and FCT Investigator contract CEECIND/01516/2017 (to SF)

    The Interaction Effect of Adverse Childhood Experiences and Socioeconomic Circumstances in Adolescent Depressive Symptomatology

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    "Purpose Limited research has examined the combined effects of psychosocial and material adversities experienced in childhood during adolescence, a sensitive period of rapid social, emotional, and cognitive development. We investigated the interaction effect of adverse childhood experiences (ACEs) and socioeconomic circumstances (SECs) during childhood on emerging self-reported depressive symptomatology among 13-year-old Portuguese adolescents. Methods We utilized data from 4,280 participants in the Generation XXI birth cohort, collected during the baseline (2005–2006), third (2016–2017), and fourth waves (2018–2020). Adjusted odds ratios and 95% confidence intervals (CIs) were obtained from binary logistic regression analyses to estimate the likelihood of depressive symptoms based on exposure to ACEs and adverse family SECs. The interaction effect of ACEs and SECs was evaluated in terms of departure from additive and multiplicative models. Results Adolescents who reported experiences of abuse, school-related problems, and household dysfunction, as well as those from less advantaged family SECs at age 10, were more likely to report moderate to severe depressive symptoms at age 13, compared to their more affluent counterparts. We observed a significant additive interaction between low household income and abuse in the development of moderate to severe depressive symptoms [relative excess risk due to interaction, 0.69, 95% CI: 0.11, 1.26]. This interaction remained statistically significant on a multiplicative scale [OR = 1.61, 95% CI: 0.99, 2.69]. Discussion ACEs and low family SECs during the first decade of life are associated with an elevated risk of moderate to severe depressive symptoms in adolescence."This study is financed by national funds through the Foundation for Science and Technology (FCT) I.P., within the scope of project “UNFOLD - In the shadow of violence: a life-course approach to unfold the scars on the body and mind over childhood and adolescence” (Ref. 2022.06837.PTDC; DOI:10.54499/2022.06837.PTDC), Epidemiology Research Unit (EPIUnit) [UIDB/04750/2020; DOI:10.54499/UIDB/04750/2020] and Laboratory for Integrative and Translational Research in Population Health (ITR) [LA/P/0064/2020; DOI:10.54499/LA/P/0064/2020]. Additionally, it is supported by the PhD grant SFRH/BD/144503/2019 (to AA) funded by FCT through the European Social Fund and the FCT Investigator contract DOI :10.54499/CEECIND/01516/2017/CP1406/CT0001 (to SF)

    Childhood social adversity and clustering of health risk behaviours during early adolescence in a population-based birth cohort

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    Objectives: This study aimed to prospectively explore the association between early lifetime exposure to psychosocial adversity and engagement in health risk behaviours (HRBs) during early adolescence. Study design: This was a prospective study. Methods: This study used data from the baseline (2005-2006), third (2016-2017) and fourth waves (2018-2020) of the Generation XXI birth cohort. Socio-economic circumstances (SECs) at baseline, adverse childhood experiences (ACEs; e.g. abuse, neglect, household dysfunction) at age 10 years and HRBs (i.e. alcohol consumption, smoking, physical exercise level, sedentary behaviours, sleep duration and eating behaviours) at age 13 years were measured. Patterns of HRBs were obtained using latent class analysis. Latent class regression analysis was used to estimate the likelihood of being engaged in HRBs according to the extent of exposure to ACEs (i.e. 0 ACEs, 1-3 ACEs, 4-5 ACEs and & GE;6 ACEs) and negative family SECs. Results: Adolescents whose mothers had a low level of education (adjusted odds ratio [aOR] = 2.72 [95% confidence interval {CI}, 2.33-3.18]), low occupational status (aOR = 3.21 [95% CI, 2.68-3.85]) and low income (aOR = 2.70 [95% CI, 2.23-3.28]) were more likely to be engaged in HRBs than their peers with higher SECs. Adolescents who experienced more ACEs were at a significantly increased risk of involve-ment in HRBs (aOR = 1.86 [95% CI, 1.33-2.63] for 4-5 ACEs vs aOR 2.41 [95% CI, 1.72-3.43] for & GE;6 ACEs). No significant gender differences were observed. Conclusions: Adolescents from families with low SECs were more likely than their more affluent coun-terparts to be engaged in HRBs. Furthermore, more ACEs contributed to widening health inequalities. & COPY; 2023 The Author(s). Published by Elsevier Ltd on behalf of The Royal Society for Public Health. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).This work was supported by the European Regional Development Fund through the Operational Programme Competitiveness and Internationalization and national funding from the Foundation for Science and Technology (FCT) , Portuguese Ministry of Science, Technology, and Higher Education under the projects HIneC: When do health inequalities start? Understanding the impact of childhood social adversity on health trajectories from birth to early adolescence (POCI-01-0145-FEDER-029567; reference: PTDC/SAU-PUB/29567/2017) . It is also supported by Unidade de Investigacao em Epidemiologia-Instituto de Saude Publica da Universidade do Porto (EPIUnit) (UIDB/04750/2020) , Laboratorio para a Investigacao Integrativa e Translacional (ITR) , Porto, Portugal (LA/P/0064/2020) , PhD grant SFRH/BD/144503/2019 (to A.A.) funded by FCT through Fundo Social Europeu, and FCT Investigator contract CEECIND/01516/2017 (to S.F.)
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