Use of Soil Surveys in the Identification of Floodplains

Author Institution: State Soil Scientist, Soil Conservation Service, U. S. Dept. of Agriculture, Columbus, Ohio 43215The frequency of flooding and depth of flood waters on alluvial soils and soils on stream terraces, was evaluated in selected sections of the Great Miami River Valley and tributaries in Montgomery and Preble Counties, Ohio. The boundaries of the highest elevations of flood waters during the floods of 1913 and 1959 were compared to the boundaries of alluvial soils and soils on stream terraces. Essentially all of the alluvial soils were inundated in both floods. About forty percent of the area of terrace soils were inundated in 1913, but less than ten percent in 1959. It is estimated that the frequency of flooding of alluvial soils is more frequent than once in forty years, and that only the very lowest portions of the terraces are inundated during floods of that frequency. Analysis of the data indicate soil surveys can be used to delineate those areas where the probability of flooding is greatest, and thus where the need for land use restrictions, such as zoning, to minimize damages due to flooding is most urgent

The Effect of Zonally Asymmetric Ozone Heating on the Northern Hemisphere Winter Polar Stratosphere

[1] Previous modeling studies have found significant differences in winter extratropical stratospheric temperatures depending on the presence or absence of zonally asymmetric ozone heating (ZAOH), yet the physical mechanism causing these differences has not been fully explained. The present study describes the effect of ZAOH on the dynamics of the Northern Hemisphere extratropical stratosphere using an ensemble of free-running atmospheric general circulation model simulations over the 1 December - 31 March period. We find that the simulations including ZAOH produce a significantly warmer and weaker stratospheric polar vortex in mid-February due to more frequent major stratospheric sudden warmings compared to the simulations using only zonal mean ozone heating. This is due to regions of enhanced Eliassen-Palm flux convergence found in the region between 40°N–70°N latitude and 10–0.05 hPa. These results are consistent with changes in the propagation of planetary waves in the presence of ZAOH predicted by an ozone-modified refractive index

Critical Current Peaks at 3BΦ3B_{\Phi} in Superconductors with Columnar Defects: Recrystalizing the Interstitial Glass

The role of commensurability and the interplay of correlated disorder and interactions on vortex dynamics in the presence of columnar pins is studied via molecular dynamics simulations. Simulations of dynamics reveal substantial caging effects and a non-monotonic dependence of the critical current with enhancements near integer values of the matching field $B_{\phi}$ and $3B_{\phi}$ in agreement with experiments on the cuprates. We find qualitative differences in the phase diagram for small and large values of the matching field.Comment: 5 pages, 4 figures (3 color

Inferring Species Trees Directly from Biallelic Genetic Markers: Bypassing Gene Trees in a Full Coalescent Analysis

The multi-species coalescent provides an elegant theoretical framework for estimating species trees and species demographics from genetic markers. Practical applications of the multi-species coalescent model are, however, limited by the need to integrate or sample over all gene trees possible for each genetic marker. Here we describe a polynomial-time algorithm that computes the likelihood of a species tree directly from the markers under a finite-sites model of mutation, effectively integrating over all possible gene trees. The method applies to independent (unlinked) biallelic markers such as well-spaced single nucleotide polymorphisms (SNPs), and we have implemented it in SNAPP, a Markov chain Monte-Carlo sampler for inferring species trees, divergence dates, and population sizes. We report results from simulation experiments and from an analysis of 1997 amplified fragment length polymorphism (AFLP) loci in 69 individuals sampled from six species of {\em Ourisia} (New Zealand native foxglove)

It takes a village to break up a match: a systemic analysis of formal youth mentoring relationship endings

BACKGROUND Although early closure of formal youth mentoring relationships has recently begun to receive some attention, more information about factors that contribute to premature endings, and how those factors interact, is needed so that empirically-based program practices can be developed and disseminated to prevent such endings and to ensure that youth reap the benefits mentoring can provide. OBJECTIVE This qualitative interview study applies a systemic model of youth mentoring relationships (Keller in J Prim Prev 26:169–188, 2005a) to the study of mentoring relationship endings in community-based mentoring matches to understand why these matches ended. METHOD Mentors, parents/guardians and program staff associated with 36 mentoring matches that had ended were interviewed about their experiences of these relationships and their understanding of why they had ended. Thematic analysis of the interview transcripts and mentoring program case notes for each match followed by systemic modeling of the relationships yielded three major findings. RESULTS A strong mentor–youth relationship is necessary but not sufficient for match longevity. The mentor–youth relationship, even when relatively strong, is unlikely to withstand disruptions in other relationships in the system. Agency contextual factors, such as program practices and policies and staffing patterns, have a critical role to play in sustaining mentoring matches, as they directly influence all of the relationships in the mentoring system. CONCLUSION These findings highlight the importance of considering not just the mentoring dyad but also the parent/guardian and program context when trying to prevent match closures. They also point to several program practices that may support longer mentoring relationships.Accepted manuscrip

Duration judgements in patients with schizophrenia

Background. The ability to encode time cues underlies many cognitive processes. In the light of schizophrenic patients' compromised cognitive abilities in a variety of domains, it is noteworthy that there are numerous reports of these patients displaying impaired timing abilities. However, the timing intervals that patients have been evaluated on in prior studies vary considerably in magnitude (e.g. 1 s, 1 min, 1 h etc.). Method. In order to obviate differences in abilities in chronometric counting and place minimal demands on cognitive processing, we chose tasks that involve making judgements about brief durations of time (<1 s). Results. On a temporal generalization task, patients were less accurate than controls at recognizing a standard duration. The performance of patients was also significantly different from controls on a temporal bisection task, in which participants categorized durations as short or long. Although time estimation may be closely intertwined with working memory, patients' working memory as measured by the digit span task did not correlate significantly with their performance on the duration judgement tasks. Moreover, lowered intelligence scores could not completely account for the findings. Conclusions. We take these results to suggest that patients with schizophrenia are less accurate at estimating brief time periods. These deficits may reflect dysfunction of biopsychological timing processes

Cosmological gravitomagnetism and Mach's principle

The spin axes of gyroscopes experimentally define local non-rotating frames. But what physical cause governs the time-evolution of gyroscope axes? We consider linear perturbations of Friedmann-Robertson-Walker cosmologies with k=0. We ask: Will cosmological vorticity perturbations exactly drag the spin axes of gyroscopes relative to the directions of geodesics to quasars in the asymptotic unperturbed FRW space? Using Cartan's formalism with local orthonormal bases we cast the laws of linear cosmological gravitomagnetism into a form showing the close correspondence with the laws of ordinary magnetism. Our results, valid for any equation of state for cosmological matter, are: 1) The dragging of a gyroscope axis by rotational perturbations of matter beyond the Hubble-dot radius from the gyroscope is exponentially suppressed, where dot is the derivative with respect to cosmic time. 2) If the perturbation of matter is a homogeneous rotation inside some radius around a gyroscope, then exact dragging of the gyroscope axis by the rotational perturbation is reached exponentially fast as the rotation radius grows beyond the H-dot radius. 3) For the most general linear cosmological perturbations the time-evolution of all gyroscope spin axes exactly follow a weighted average of the energy currents of cosmological matter. The weight function is the same as in Ampere's law except that the inverse square law is replaced by the Yukawa force with the Hubble-dot cutoff. Our results demonstrate (in first order perturbation theory for FRW cosmologies with k = 0) the validity of Mach's hypothesis that axes of local non-rotating frames precisely follow an average of the motion of cosmic matter.Comment: 18 pages, 1 figure. Comments and references adde