12,188 research outputs found

    Mother, researcher, feminist, woman: reflections on maternal status as researcher identity

    Get PDF
    Purpose – The purpose of this paper is to discuss the ways in which a researcher's maternal status as “mother” or “non-mother/child-free” is implicated in the research process. Design/methodology/approach – This paper draws on the experiences as two feminist researchers who each independently researched experiences of motherhood: one as a “mother” and one as a “non-mother/child-free”. The paper draws on extracts from the original interview data and research diaries to reflect on how research topic, methodology and interview practice are shaped by a researcher's maternal status. Findings – The paper found that the own maternal identities shaped the research process in a number of ways: it directed the research topic and access to research participants; it drove the method of data collection and analysis and it shaped how the authors interacted with the participants in the interview setting, notably through the performance of maternal identity. The paper concludes by examining how pervasive discourses of “good motherhood” are both challenged and reproduced by a researcher's maternal status and question the implications of this for feminist research. Originality/value – While much has been written about researcher “positionality” and the impact of researcher identity on the research process, the ways in which a researcher's “maternal status” is implicated in the research process has been left largely unexamined. Yet, as this paper highlights, the interaction of the often-conflicting identities of “mother”, “researcher”, “feminist” and “woman” may shape the research process in subtle yet profound ways, raising important questions about the limits of what feminist social research about “motherhood” can achieve

    Microscopic optical potential from chiral nuclear forces

    Full text link
    The energy- and density-dependent single-particle potential for nucleons is constructed in a medium of infinite isospin-symmetric nuclear matter starting from realistic nuclear interactions derived within the framework of chiral effective field theory. The leading-order terms from both two- and three-nucleon forces give rise to real, energy-independent contributions to the nucleon self-energy. The Hartree-Fock contribution from the two-nucleon force is attractive and strongly momentum dependent, in contrast to the contribution from the three-nucleon force which provides a nearly constant repulsive mean field that grows approximately linearly with the nuclear density. Together, the leading-order perturbative contributions yield an attractive single-particle potential that is however too weak compared to phenomenology. Second-order contributions from two- and three-body forces then provide the additional attraction required to reach the phenomenological depth. The imaginary part of the optical potential, which is positive (negative) for momenta below (above) the Fermi momentum, arises at second-order and is nearly inversion-symmetric about the Fermi surface when two-nucleon interactions alone are present. The imaginary part is strongly absorptive and requires the inclusion of an effective mass correction as well as self-consistent single-particle energies to attain qualitative agreement with phenomenology.Comment: 12 pages, 7 figures, added references, corrected typo

    Viking '75 spacecraft design and test summary. Volume 3: Engineering test summary

    Get PDF
    The engineering test program for the lander and the orbiter are presented. The engineering program was developed to achieve confidence that the design was adequate to survive the expected mission environments and to accomplish the mission objective

    Model-independent constraints on contact interactions from LEP2 data analysis

    Get PDF
    We derive model-independent constraints on four-fermion contact interaction-type dynamics from the published preliminary LEP2 experimental data on e^+e^- annihilation into \mu^+\mu^- and \tau^+\tau^- pairs, measured at different energies between 130 and 207 GeV. The basic observables are chosen to be the total cross section and the forward-backward asymmetry, and the analysis realistically takes into account data uncertainties and correlations among measurements at the various energies. The combination of data from different energy points plays an important role in the determination of regions allowed for the contact interaction coupling constants. In contrast to the more common one-parameter analyses, we only obtain constraints on pairs of parameters rather than limits on individual ones.Comment: 13 pages, LaTeX, including figures. v2: Included discussion of tau data, version to appear in EPJ

    Viking '75 spacecraft design and test summary. Volume 1: Lander design

    Get PDF
    The Viking Mars program is summarized. The design of the Viking lander spacecraft is described

    A data driven nonlinear stochastic model for blood glucose dynamics

    Get PDF
    The development of adequate mathematical models for blood glucose dynamics may improve early diagnosis and control of diabetes mellitus (DM). We have developed a stochastic nonlinear second order differential equation to describe the response of blood glucose concentration to food intake using continuous glucose monitoring (CGM) data. A variational Bayesian learning scheme was applied to define the number and values of the system's parameters by iterative optimisation of free energy. The model has the minimal order and number of parameters to successfully describe blood glucose dynamics in people with and without DM. The model accounts for the nonlinearity and stochasticity of the underlying glucose–insulin dynamic process. Being data-driven, it takes full advantage of available CGM data and, at the same time, reflects the intrinsic characteristics of the glucose–insulin system without detailed knowledge of the physiological mechanisms. We have shown that the dynamics of some postprandial blood glucose excursions can be described by a reduced (linear) model, previously seen in the literature. A comprehensive analysis demonstrates that deterministic system parameters belong to different ranges for diabetes and controls. Implications for clinical practice are discussed. This is the first study introducing a continuous data-driven nonlinear stochastic model capable of describing both DM and non-DM profiles

    Chiral nucleon-nucleon forces in nuclear structure calculations

    Get PDF
    Realistic nuclear potentials, derived within chiral perturbation theory, are a major breakthrough in modern nuclear structure theory, since they provide a direct link between nuclear physics and its underlying theory, namely the QCD. As a matter of fact, chiral potentials are tailored on the low-energy regime of nuclear structure physics, and chiral perturbation theory provides on the same footing two-nucleon forces as well as many-body ones. This feature fits well with modern advances in ab-initio methods and realistic shell-model. Here, we will review recent nuclear structure calculations, based on realistic chiral potentials, for both finite nuclei and infinite nuclear matter.Comment: 10 pages, 8 figures, plenary talk presented at "Nucleus-Nucleus 2015" Conference, 21-26 June 2015, Catania, to be published in the "Conference Proceedings" Series of the Italian Physical Societ

    X-ray observations of Algol

    Get PDF
    Observations of Algol using a solid state spectrometer onboard the Einstein Observatory are discussed. Two observations six months apart were made, both during a primary optical eclipse. No corresponding X-ray eclipses were seen. During the second observation the source was flaring and was on average a factor three brighter. The spectrum on both occasions was consistent with a two-component thermal equilibrium model with temperatures of approximately 7.5 and 40 million degrees. Attempts to insert a third component indicate the temperature distribution to be bimodal. Models for the X-ray emission are discussed and it is suggested that the emission most likely originates from an active corona surrounding the K star
    • …
    corecore