Virtual Compton Scattering and Neutral Pion Electroproduction in the Resonance Region up to the Deep Inelastic Region at Backward Angles

We have made the first measurements of the virtual Compton scattering (VCS) process via the H$(e,e'p)\gamma$ exclusive reaction in the nucleon resonance region, at backward angles. Results are presented for the $W$-dependence at fixed $Q^2=1$ GeV$^2$, and for the $Q^2$-dependence at fixed $W$ near 1.5 GeV. The VCS data show resonant structures in the first and second resonance regions. The observed $Q^2$-dependence is smooth. The measured ratio of H$(e,e'p)\gamma$ to H$(e,e'p)\pi^0$ cross sections emphasizes the different sensitivity of these two reactions to the various nucleon resonances. Finally, when compared to Real Compton Scattering (RCS) at high energy and large angles, our VCS data at the highest $W$ (1.8-1.9 GeV) show a striking $Q^2$- independence, which may suggest a transition to a perturbative scattering mechanism at the quark level.Comment: 20 pages, 8 figures. To appear in Phys.Rev.

Virtual Compton Scattering and the Generalized Polarizabilities of the Proton at Q^2=0.92 and 1.76 GeV^2

Virtual Compton Scattering (VCS) on the proton has been studied at Jefferson Lab using the exclusive photon electroproduction reaction (e p --> e p gamma). This paper gives a detailed account of the analysis which has led to the determination of the structure functions P_LL-P_TT/epsilon and P_LT, and the electric and magnetic generalized polarizabilities (GPs) alpha_E(Q^2) and beta_M(Q^2) at values of the four-momentum transfer squared Q^2= 0.92 and 1.76 GeV^2. These data, together with the results of VCS experiments at lower momenta, help building a coherent picture of the electric and magnetic GPs of the proton over the full measured Q^2-range, and point to their non-trivial behavior.Comment: version 2: modified according to PRC Editor's and Referee's recommendations. Archival paper for the E93-050 experiment at JLab Hall A. 28 pages, 23 figures, 5 cross-section tables. To be submitted to Phys.Rev.

Backward electroproduction of pi0 mesons on protons in the region of nucleon resonances at four momentum transfer squared Q**2 = 1.0 GeV**2

Exclusive electroproduction of pi0 mesons on protons in the backward hemisphere has been studied at Q**2 = 1.0 GeV**2 by detecting protons in the forward direction in coincidence with scattered electrons from the 4 GeV electron beam in Jefferson Lab's Hall A. The data span the range of the total (gamma* p) center-of-mass energy W from the pion production threshold to W = 2.0 GeV. The differential cross sections sigma_T+epsilon*sigma_L, sigma_TL, and sigma_TT were separated from the azimuthal distribution and are presented together with the MAID and SAID parametrizations.Comment: 17 pages, 11 figures, information can be found at http://hallaweb.jlab.org/experiment/E93-050/vcs.html updated content about SAID analysis updated MAID results following new reference nucl-th/0310041 updated figure

COSMIC (Cohort Studies of Memory in an International Consortium): An international consortium to identify risk and protective factors and biomarkers of cognitive ageing and dementia in diverse ethnic and sociocultural groups

BACKGROUND: A large number of longitudinal studies of population-based ageing cohorts are in progress internationally, but the insights from these studies into the risk and protective factors for cognitive ageing and conditions like mild cognitive impairment and dementia have been inconsistent. Some of the problems confounding this research can be reduced by harmonising and pooling data across studies. COSMIC (Cohort Studies of Memory in an International Consortium) aims to harmonise data from international cohort studies of cognitive ageing, in order to better understand the determinants of cognitive ageing and neurocognitive disorders. METHODS/DESIGN: Longitudinal studies of cognitive ageing and dementia with at least 500 individuals aged 60 years or over are eligible and invited to be members of COSMIC. There are currently 17 member studies, from regions that include Asia, Australia, Europe, and North America. A Research Steering Committee has been established, two meetings of study leaders held, and a website developed. The initial attempts at harmonising key variables like neuropsychological test scores are in progress. DISCUSSION: The challenges of international consortia like COSMIC include efficient communication among members, extended use of resources, and data harmonisation. Successful harmonisation will facilitate projects investigating rates of cognitive decline, risk and protective factors for mild cognitive impairment, and biomarkers of mild cognitive impairment and dementia. Extended implications of COSMIC could include standardised ways of collecting and reporting data, and a rich cognitive ageing database being made available to other researchers. COSMIC could potentially transform our understanding of the epidemiology of cognitive ageing, and have a world-wide impact on promoting successful ageing

Measurement of the Generalized Polarizabilities of the Proton in Virtual Scattering at Q2=0.92 and 1.76 GeV2: I. Low Energy Expansion Analysis

Virtual Compton Scattering is studied at the Thomas Jefferson National Accelerator Facility at low Center-of-Mass energies, below pion threshold. Following the Low Energy Theorem for the $ep \to ep \gamma$ process, we obtain values for the two structure functions Pll-Ptt/epsilon and Plt at four-momentum transfer squared Q2=0.92 and 1.76 GeV2.Comment: 4 pages, 2 figures, to be submitted to PRL. Figs 1 and 2, lettering enlarge

COSMIC (Cohort Studies of Memory in an International Consortium): An international consortium to identify risk and protective factors and biomarkers of cognitive ageing and dementia...

Background: A large number of longitudinal studies of population-based ageing cohorts are in progress internationally, but the insights from these studies into the risk and protective factors for cognitive ageing and conditions like mild cognitive impairment and dementia have been inconsistent. Some of the problems confounding this research can be reduced by harmonising and pooling data across studies. COSMIC (Cohort Studies of Memory in an International Consortium) aims to harmonise data from international cohort studies of cognitive ageing, in order to better understand the determinants of cognitive ageing and neurocognitive disorders. Methods/Design: Longitudinal studies of cognitive ageing and dementia with at least 500 individuals aged 60 years or over are eligible and invited to be members of COSMIC. There are currently 17 member studies, from regions that include Asia, Australia, Europe, and North America. A Research Steering Committee has been established, two meetings of study leaders held, and a website developed. The initial attempts at harmonising key variables like neuropsychological test scores are in progress. Discussion: The challenges of international consortia like COSMIC include efficient communication among members, extended use of resources, and data harmonisation. Successful harmonisation will facilitate projects investigating rates of cognitive decline, risk and protective factors for mild cognitive impairment, and biomarkers of mild cognitive impairment and dementia. Extended implications of COSMIC could include standardised ways of collecting and reporting data, and a rich cognitive ageing database being made available to other researchers. COSMIC could potentially transform our understanding of the epidemiology of cognitive ageing, and have a world-wide impact on promoting successful ageing

Genital Culture: Exploring the Cultural Importance of Genital Surgery in the West

In “Feminism Versus Multiculturalism”, Leti Volpp argues that Western conceptions of third-world culture as uniquely oppressive to women work to conceal the ways that Western culture itself also promotes patriarchal and normative practices that can be dangerous and degrading to women. In this paper, I will take up this argument by demonstrating how Western discourse vilifies cultures that engage in female genital mutilation (FGM) without realizing how the Western practices of intersex surgery and cosmetic vaginal surgery are also culturally imbued practices that can be seen as forms of genital mutilation. The assumed importance of genital surgery for intersex infants as well as the rising popularity of cosmetic surgery for women’s genitals exemplify the importance placed on gender distinction though genital appearance in our culture. Genital surgeries such as these are tied to the idealized conception of the gender binary that exists in Western culture. Despite the reality that genitals, especially the vagina, vary widely in appearance (size, shape, colour), the belief that there are norms of genital appearance that need to be adhered to for females and males continues to be propagated within Western culture. Suzanne Kessler’s work on intersex surgeries and Virginia Braun’s work on the growing popularity of cosmetic genital surgeries both illustrate how these norms are acted upon through genital surgery. This paper will perform an in-depth examination of these trends to reveal the similarities between Western genital surgeries and FGM by exposing how Western cultural values also regulate the female body

Online Sexual Violence, Child Pornography or Something Else Entirely? Police Responses to Non-Consensual Intimate Image Sharing among Youth

Due to child pornography laws, non-consensual intimate image sharing among youth is subjected to complex legal landscapes in a variety of jurisdictions such as Canada, the United States, the United Kingdom, and Australia. While a growing number of scholars have problematized the use of child pornography charges to respond to these cases, there remains little understanding regarding how the police that enforce these laws conceptualize this issue and how this influences responses to these cases. Drawing from interviews with members of sex crime–related units in police service organizations from across Canada, this article examines how police conceptions of non-consensual intimate image sharing among youth correspond with and/or diverge from legal and critical understandings of this issue. While it is widely understood that online and digitally enabled forms of sexual violence pose unique challenges for police, our research fills a gap in the literature by examining how police themselves understand and respond to these challenges

“I Think It’s Re-Victimizing Victims Almost Every Time”: Police Perceptions of Criminal Justice Responses to Sexual Violence

Criminal justice responses to sexual violence have long been critiqued for either failing or further victimizing complainants. The ways that police can be complicit in these shortcomings is well documented, but less is known about how police officers themselves identify and understand the barriers to justice within the criminal justice system. In this article, we use data from 70 semi-structured interviews and two focus groups with sex crime investigators to explore police interpretations of the obstacles to achieving justice in cases of sexual violence. Our findings demonstrate that the majority of officers are critical of the present criminal justice response to sexual violence and are doubtful of its ability to provide a semblance of justice to the majority of victims