Groundwater Hydrology of a Population of Lindera melissifolia in Arkansas

Groundwater hydrology was monitored from October through August in and around a bottomland forest pond containing Lindera melissifolia, pondberry. The study site exhibited a series of low ancient dunes and depressions, with seasonal ponds in the depressions. Ponds showed no surface inlets or outlets. Shallow wells were made and soil cores removed along a transect from the top of one dune across the pond to a lower dune. Piezometers were installed in the wells and groundwater levels monitored. Soil core samples were analyzed to determine particle size distribution at soil profile positions selected during field analysis. It was shown that a subsurface hydrologic gradient exists between surrounding dune slopes and the pond bottom, delivering groundwater to the pond during the season when precipitation exceeds evapotranspiration. The hydrologic gradient was shown to be substrate-dependent

Evidence for a singularity in ideal magnetohydrodynamics: implications for fast reconnection

Numerical evidence for a finite-time singularity in ideal 3D magnetohydrodynamics (MHD) is presented. The simulations start from two interlocking magnetic flux rings with no initial velocity. The magnetic curvature force causes the flux rings to shrink until they come into contact. This produces a current sheet between them. In the ideal compressible calculations, the evidence for a singularity in a finite time $t_c$ is that the peak current density behaves like $|J|_\infty \sim 1/(t_c-t)$ for a range of sound speeds (or plasma betas). For the incompressible calculations consistency with the compressible calculations is noted and evidence is presented that there is convergence to a self-similar state. In the resistive reconnection calculations the magnetic helicity is nearly conserved and energy is dissipated.Comment: 4 pages, 4 figure

Quark-Gluon Plasma as a Condensate of Z(3) Wilson Lines

Effective theories for the thermal Wilson line are constructed in an SU(N) gauge theory at nonzero temperature. I propose that the order of the deconfining phase transition for Z(N) Wilson lines is governed by the behavior of SU(N) Wilson lines. In a mean field theory, the free energy in the deconfined phase is controlled by the condensate for Z(N) Wilson lines. Numerical simulations on the lattice, and the mean field theory for Z(3) Wilson lines, suggest that about any finite temperature transition in QCD, the dominant correlation length increases by a large, uniform factor, of order five.Comment: 5 pages, LaTe

Lecture, écriture et croyance dans la France du xixe siècle : la réception de la Vie de Jésus de Renan auprès du grand public

La Vie de Jésus d’Ernest Renan, publiée le 24 juin 1863, fut, dans l’Europe du xixe siècle, l’une des sensations éditoriales dans le domaine non fictionnel. Produite dans un contexte d’alphabétisation croissante et de baisse des coûts d’impression, la biographie historique du fondateur du christianisme par Renan s’est vendue bien mieux que les travaux académiques de ses collègues, mais aussi que les œuvres de nombreux romanciers célèbres. Cet article examine sous un angle nouveau la controverse touchant à la Vie de Jésus, en adoptant le point de vue des lecteurs. Après une analyse des origines, du contenu intellectuel et de la réception imprimée du livre, on prend en compte un matériel d’archives largement négligé, issu de la correspondance personnelle de Renan. L’analyse qui en résulte fournit une nouvelle grille de lecture du succès de la Vie de Jésus, qui met l’accent sur son attrait pour ceux qui sont, au sein de la société française, s’efforçaient de concilier les revendications de la foi et celles de la raison. En même temps, l’article suggère que l’opposition à l’égard de Renan était enracinée dans des facteurs qui allaient bien au-delà de ses positions sur le christianisme, en particulier dans la forme romanesque de son écriture. Cette critique avait également une dimension genrée, dans le contexte d’une inquiétude généralisée des élites concernant l’absence de médiation des lectures féminines.Ernest Renan’s Vie de Jésus, published on 24 June 1863, was one of the nonfiction sensations of nineteenth-century Europe. Produced in a context of expanding literacy and declining print costs, Renan’s historical biography of the founder of Christianity outsold not only the author’s academic colleagues, but also many famous novelists. This article re-examines the controversy around Vie de Jésus from the perspective of its readers. After an analysis of the origins, intellectual content, and print reception of the book, it moves on to largely neglected archival material from Renan’s personal correspondence. The resulting analysis provides a new account of the success of Vie de Jésus that focuses on its appeal to those a seam of French society who wanted to reconcile the claims of faith and reason. At the same time, the article suggests that opposition to Renan was rooted in factors that extended beyond his conclusions about Christianity, most notably the novelistic form of his writing; this critique also had a gendered dimension in the context of widespread elite anxieties about unmediated female reading

Magnetohydrodynamic Waves in an Asymmetric Magnetic Slab

Analytical models of solar atmospheric magnetic structures have been crucial for our understanding of magnetohydrodynamic (MHD) wave behaviour and in the development of the field of solar magneto-seismology. Here, an analytical approach is used to derive the dispersion relation for MHD waves in a magnetic slab of homogeneous plasma enclosed on its two sides by non-magnetic, semi-infinite plasma with different densities and temperatures. This generalises the classic magnetic slab model, which is symmetric about the slab. The dispersion relation, unlike that governing a symmetric slab, cannot be decoupled into the well-known sausage and kink modes, i.e. the modes have mixed properties. The eigenmodes of an asymmetric magnetic slab are better labelled as quasi-sausage and quasi-kink modes. Given that the solar atmosphere is highly inhomogeneous, this has implications for MHD mode identification in a range of solar structures. A parametric analysis of how the mode properties (in particular the phase speed, eigenfrequencies, and amplitudes) vary in terms of the introduced asymmetry is conducted. In particular, avoided crossings occur between quasi-sausage and quasi-kink surface modes, allowing modes to adopt different properties for different parameters in the external region

Racism as a determinant of health: a systematic review and meta-analysis

Despite a growing body of epidemiological evidence in recent years documenting the health impacts of racism, the cumulative evidence base has yet to be synthesized in a comprehensive meta-analysis focused specifically on racism as a determinant of health. This meta-analysis reviewed the literature focusing on the relationship between reported racism and mental and physical health outcomes. Data from 293 studies reported in 333 articles published between 1983 and 2013, and conducted predominately in the U.S., were analysed using random effects models and mean weighted effect sizes. Racism was associated with poorer mental health (negative mental health: r = -.23, 95% CI [-.24,-.21], k = 227; positive mental health: r = -.13, 95% CI [-.16,-.10], k = 113), including depression, anxiety, psychological stress and various other outcomes. Racism was also associated with poorer general health (r = -.13 (95% CI [-.18,-.09], k = 30), and poorer physical health (r = -.09, 95% CI [-.12,-.06], k = 50). Moderation effects were found for some outcomes with regard to study and exposure characteristics. Effect sizes of racism on mental health were stronger in cross-sectional compared with longitudinal data and in non-representative samples compared with representative samples. Age, sex, birthplace and education level did not moderate the effects of racism on health. Ethnicity significantly moderated the effect of racism on negative mental health and physical health: the association between racism and negative mental health was significantly stronger for Asian American and Latino(a) American participants compared with African American participants, and the association between racism and physical health was significantly stronger for Latino(a) American participants compared with African American participants.<br /