The Role of Final State Interactions in Quasielastic 56^{56}Fe(e,e′)(e,e') Reactions at large ∣q⃗∣|\vec q|

A relativistic finite nucleus calculation using a Dirac optical potential is used to investigate the importance of final state interactions [FSI] at large momentum transfers in inclusive quasielastic electronuclear reactions. The optical potential is derived from first-order multiple scattering theory and then is used to calculate the FSI in a nonspectral Green's function doorway approach. At intermediate momentum transfers excellent predictions of the quasielastic $^{56}$Fe$(e,e')$ experimental data for the longitudinal response function are obtained. In comparisons with recent measurements at $|{\vec q|}=1.14$~GeV/c the theoretical calculations of $R_L$ give good agreement for the quasielastic peak shape and amplitude, but place the position of the peak at an energy transfer of about $40$~MeV higher than the data.Comment: 13 pages typeset using revtex 3.0 with 6 postscript figures in accompanying uuencoded file; submitted to Phys. Rev.

Doing Epistemic (In)justice to Semenya

In August 2009, Caster Semenya won the women’s 800m event at the International Association of Athletics Federations World Championships in Berlin. This victory became a global news story not because Semenya was a newcomer to athletics who had outperformed an established field – but because of the fact that before the race she had been asked to undergo tests to determine whether or not she was a woman. This article uses a hermeneutics of suspicion to argue that the controversy surrounding Semenya was based on a set of assumptions that, although incorrect, drew on hegemonic understandings of sex and gender that dominate the discourse of sport, and were adopted by the media without question. As a consequence, Semenya became the victim of what Miranda Fricker has termed epistemic injustice – a condition that arises when individuals or experiences are marginalized as a result of the absence of concepts and language that would enable us to articulate reality differently

Racial Disparities in Functional Limitations Among Hispanic Women in the United States

This paper assesses whether there are race differences in functional health among Hispanic women in the United States; ascertains whether the race differences in functional health vary by age; and examines the extent to which race differences in functional health are attributable to key dimensions of demographic, geographic, and socioeconomic heterogeneity. The analysis is based on 15 years of aggregated data from the National Health Interview Survey. Both U.S.- and foreign-born black and other race Hispanic women display a higher level of functional limitations than their white Hispanic counterparts. There is little evidence that such health differences widen with age. U.S.-born black Hispanic women, however, suffer from a high burden of functional limitations across the adult age range. This research speaks to the need for greater attention to racial differences in health among Hispanics, and particularly so within the U.S.-born segment of this rapidly aging population

Full-Folding Optical Potentials for Elastic Nucleon-Nucleus Scattering based on Realistic Densities

Optical model potentials for elastic nucleon nucleus scattering are calculated for a number of target nuclides from a full-folding integral of two different realistic target density matrices together with full off-shell nucleon-nucleon t-matrices derived from two different Bonn meson exchange models. Elastic proton and neutron scattering observables calculated from these full-folding optical potentials are compared to those obtained from `optimum factorized' approximations in the energy regime between 65 and 400 MeV projectile energy. The optimum factorized form is found to provide a good approximation to elastic scattering observables obtained from the full-folding optical potentials, although the potentials differ somewhat in the structure of their nonlocality.Comment: 21 pages, LaTeX, 17 postscript figure

An improved error assessment for the GEM-T1 gravitational model

Several tests were designed to determine the correct error variances for the GEM-T1 gravitational solution which was derived exclusively from satellite tracking data. The basic method employs both wholly independent and dependent subset data solutions and produces a full field coefficient by coefficient estimate of the model uncertainties. The GEM-T1 errors were further analyzed using a method based upon eigenvalue-eigenvector analysis which calibrates the entire covariance matrix. Dependent satellite and independent altimetric and surface gravity data sets, as well as independent satellite deep resonance information, confirm essentially the same error assessment

Energy Dependence of the NN t-matrix in the Optical Potential for Elastic Nucleon-Nucleus Scattering

The influence of the energy dependence of the free NN t-matrix on the optical potential of nucleon-nucleus elastic scattering is investigated within the context of a full-folding model based on the impulse approximation. The treatment of the pole structure of the NN t-matrix, which has to be taken into account when integrating to negative energies is described in detail. We calculate proton-nucleus elastic scattering observables for $^{16}$O, $^{40}$Ca, and $^{208}$Pb between 65 and 200 MeV laboratory energy and study the effect of the energy dependence of the NN t-matrix. We compare this result with experiment and with calculations where the center-of-mass energy of the NN t-matrix is fixed at half the projectile energy. It is found that around 200 MeV the fixed energy approximation is a very good representation of the full calculation, however deviations occur when going to lower energies (65 MeV).Comment: 11 pages (revtex), 6 postscript figure

Country characteristics and the incidence of capital income taxation on wages: an empirical assessment

This paper examines the incidence of corporate income taxes on wages using data from the US Bureau of Labor Statistics for 13 OECD countries. Within a wage-bargaining framework, our econometric analysis shows that a substantial share of the corporate tax burden is shifted from capital to labour. However, the magnitude of this shift is influenced importantly by country characteristics affecting the process of wage determination, such as the degree of capital mobility, a country's relative influence over the world price of output and trade unions’ strength

Sensitivities of the Proton-Nucleus Elastical Scattering Observables of 6He and 8He at Intermediate Energies

We investigate the use of proton-nucleus elastic scattering experiments using secondary beams of 6He and 8He to determine the physical structure of these nuclei. The sensitivity of these experiments to nuclear structure is examined by using four different nuclear structure models with different spatial features using a full-folding optical potential model. The results show that elastic scattering at intermediate energies (<100 MeV per nucleon) is not a good constraint to be used to determine features of structure. Therefore researchers should look elsewhere to put constraints on the ground state wave function of the 6He and 8He nuclei.Comment: To be published in Phys. Rev.

Ultra-broadband wavelength-swept Tm-doped fiber laser using wavelength-combined gain stages

A wavelength-swept thulium-doped fiber laser system employing two parallel cavities with two different fiber gain stages is reported. The fiber gain stages were tailored to provide emission in complementary bands with external wavelength-dependent feedback cavities sharing a common rotating polygon mirror for wavelength scanning. The wavelength-swept laser outputs from the fiber gain elements were spectrally combined by means of a dichroic mirror and yielded over 500 mW of output with a scanning range from ~1740 nm to ~2070 nm for a scanning frequency of ~340 Hz

The diagnosis of scientific reasoning skills: how teachers' professional knowledge predicts their diagnostic accuracy

Diagnostic competences of teachers are an essential prerequisite for the individual support of students and, therefore, highly important. There is a substantial amount of research on teachers’ diagnostic competences, mostly operationalized as diagnostic accuracy, and on how diagnostic competences may be influenced by teachers’ professional knowledge base. While this line of research already includes studies on the influence of teachers’ content knowledge (CK), pedagogical content knowledge (PCK), and pedagogical-psychological knowledge (PK) on the diagnosis of subject-specific knowledge or skills, research on the diagnosis of cross-domain skills (i.e., skills relevant for more than one subject), such as scientific reasoning, is lacking although students’ scientific reasoning skills are regarded as important for multiple school subjects (e.g., biology or physics). This study investigates how the accuracy of pre-service teachers’ diagnosis of scientific reasoning is influenced by teachers’ own scientific reasoning skills (one kind of CK), their topic-specific knowledge (i.e., knowledge about a topic that constitutes the thematic background for teaching scientific reasoning; which is another kind of CK), and their knowledge about the diagnosis of scientific reasoning (one kind of PCK) and whether the relationships between professional knowledge and diagnostic accuracy are similar across subjects. The design of the study was correlational. The participants completed several tests for the kinds of professional knowledge mentioned and questionnaires for several control variables. To ensure sufficient variation in pre-service teachers’ PCK, half of the participants additionally read a text about the diagnosis of scientific reasoning. Afterwards, the participants completed one of two parallel video-based simulations (depicting a biology or physics lesson) measuring diagnostic accuracy. The pre-service teachers’ own scientific reasoning skills (CK) were a statistically significant predictor of diagnostic accuracy, whereas topic-specific knowledge (CK) or knowledge about the diagnosis of scientific reasoning (PCK), as manipulated by the text, were not. Additionally, no statistically significant interactions between subject (biology or physics) and the different kinds of professional knowledge were found. These findings emphasize that not all facets of professional knowledge seem to be equally important for the diagnosis of scientific reasoning skills, but more research is needed to clarify the generality of these findings