Chemical Composition of Ground Water and the Locations of Permeable Zones in the Yucca Mountain Area, Nevada

Ten wells in the Yucca Mountain area of southern Nevada have been sampled for chemical analysis. Samples were obtained during pumping of water from the entire well bore (composite sample) and in one instance by pumping water from a single isolated interval in well UE-25b#1. Sodium is the most abundant cation and bicarbonate the most abundant anion in all water samples. Although the general chemical compositions of individual samples are similar, there are significant differences in uncorrected carbon-14 age and in inorganic and stable-isotope composition. Flow surveys of seven wells performed using iodine-131 as a tracer indicate that ground-water production is usually from one or more discrete zones of permeability

Energy Dissipation and Air Entrainment in a Stepped Storm Waterway: an Experimental Study

For the last three decades, research focused on steep stepped chutes. Few studies considered flat-slope stepped geometries such as stepped storm waterways or culverts. In this study, experiments were conducted in a large, flat stepped chute (~3.4 degrees) based upon a Froude similitude. Three basic flow regimes were observed: nappe flow without hydraulic jump, transition flow, and skimming flow. Detailed air-water flow measurements were conducted. The results allow a complete characterization of the air concentration and bubble count rate distributions, as well as an accurate estimate of the rate of energy dissipation. The flow resistance, expressed in terms of a modified friction slope, was found to be about 2.5 times greater than in smooth-chute flow. A comparison between smooth- and stepped-invert flows shows that greater aeration and larger residence times take place in the latter geometry. The result confirms the air-water mass transfer potential of stepped cascades, even for flat slopes

Time evolution and observables in constrained systems

The discussion is limited to first-class parametrized systems, where the definition of time evolution and observables is not trivial, and to finite dimensional systems in order that technicalities do not obscure the conceptual framework. The existence of reasonable true, or physical, degrees of freedom is rigorously defined and called {\em local reducibility}. A proof is given that any locally reducible system admits a complete set of perennials. For locally reducible systems, the most general construction of time evolution in the Schroedinger and Heisenberg form that uses only geometry of the phase space is described. The time shifts are not required to be 1symmetries. A relation between perennials and observables of the Schroedinger or Heisenberg type results: such observables can be identified with certain classes of perennials and the structure of the classes depends on the time evolution. The time evolution between two non-global transversal surfaces is studied. The problem is posed and solved within the framework of the ordinary quantum mechanics. The resulting non-unitarity is different from that known in the field theory (Hawking effect): state norms need not be preserved so that the system can be lost during the evolution of this kind.Comment: 31 pages, Latex fil

Immunization Milestones: A More Comprehensive Picture of Age-Appropriate Vaccination

A challenge facing immunization registries is developing measures of childhood immunization coverage that contain more information for setting policy than present vaccine series up-to-date (UTD) rates. This study combined milestone analysis with provider encounter data to determine when children either do not receive indicated immunizations during medical encounters or fail to visit providers. Milestone analysis measures immunization status at key times between birth and age 2, when recommended immunizations first become late. The immunization status of a large population of children in the Oregon ALERT immunization registry and in the Oregon Health Plan was tracked across milestone ages. Findings indicate that the majority of children went back and forth with regard to having complete age-appropriate immunizations over time. We also found that immunization UTD rates when used alone are biased towards relating non-UTD status to a lack of visits to providers, instead of to provider visits on which recommended immunizations are not given

New Distributional Records and Natural History Notes on Selected Fishes from Arkansas

This report documents new records on the distribution of selected fishes from Arkansas and provides notes on their natural history. We document new geographic records for 21 species within 8 families in 12 counties of the state. Most importantly we have included new records for fishes ranked S1, S2 or S3 in the state by NatureServe and several Species of Special Concern by the Arkansas Game and Fish Commission (AGFC). Additional collections of fishes in the state will undoubtedly provide more records especially with the use of electroshocking devices as has been shown herein

Feeding behavior of the ctenophore Thalassocalyce inconstans : revision of anatomy of the order Thalassocalycida

© 2009 The Authors. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License. The definitive version was published in Marine Biology 156 (2009): 1049-1056, doi:10.1007/s00227-009-1149-6.Behavioral observations using a remotely operated vehicle (ROV) in the Gulf of California in March, 2003, provided insights into the vertical distribution, feeding and anatomy of the rare and delicate ctenophore Thalassocalyce inconstans. Additional archived ROV video records from the Monterey Bay Aquarium Research Institute of 288 sightings of T. inconstans and 2,437 individual observations of euphausiids in the Gulf of California and Monterey Canyon between 1989 and 2005 were examined to determine ctenophore and euphausiid prey depth distributions with respect to temperature and dissolved oxygen concentration [dO]. In the Gulf of California most ctenophores (96.9%) were above 350 m, the top of the oxygen minimum layer. In Monterey Canyon the ctenophores were more widely distributed throughout the water column, including the hypoxic zone, to depths as great as 3,500 m. Computer-aided behavioral analysis of two video records of the capture of euphausiids by T. inconstans showed that the ctenophore contracted its bell almost instantly (0.5 s), transforming its flattened, hemispherical resting shape into a closed bi-lobed globe in which seawater and prey were engulfed. Euphausiids entrapped within the globe displayed a previously undescribed escape response for krill (‘probing behavior’), in which they hovered and gently probed the inner surfaces of the globe with antennae without stimulating further contraction by the ctenophore. Such rapid bell contraction could be effected only by a peripheral sphincter muscle even though the presence of circumferential ring musculature was unknown for the Phylum Ctenophora. Thereafter, several live T. inconstans were collected by hand off Barbados and microscopic observations confirmed that assumption.Supported by the David and Lucile Packard Foundation and NOAA Grant #NA06OAR4600091

Childhood and maternal infections and risk of acute leukaemia in children with Down syndrome: a report from the Children's Oncology Group

Childhood and maternal infections and risk of acute leukaemia in children with Down syndrome: a report from the Children's Oncology Grou

The Role of Magnetic Shear in Reconnection-Driven Flare Energy Release

Using observations from the Solar Dynamics Observatory's Atmosphere Imaging Assembly and the Ramaty High Energy Solar Spectroscopic Imager, we present novel measurements of the shear of post-reconnection flare loops (PRFLs) in SOL20141218T21:40 and study its evolution with respect to magnetic reconnection and flare emission. Two quasi-parallel ribbons form adjacent to the magnetic polarity inversion line (PIL), spreading in time first parallel to the PIL and then mostly in a perpendicular direction. We measure magnetic reconnection rate from the ribbon evolution, and also the shear angle of a large number of PRFLs observed in extreme ultraviolet passbands ($\lesssim$1 MK). For the first time, the shear angle measurements are conducted using several complementary techniques allowing for a cross-validation of the results. In this flare, the total reconnection rate is much enhanced before a sharp increase of the hard X-ray emission, and the median shear decreases from 60$^\circ$-70$^\circ$ to 20$^\circ$, on a time scale of ten minutes. We find a correlation between the shear-modulated total reconnection rate and the non-thermal electron flux. These results confirm the strong-to-weak shear evolution suggested in previous observational studies and reproduced in numerical models, and also confirm that, in this flare, reconnection is not an efficient producer of energetic non-thermal electrons during the first ten minutes when the strongly sheared PRFLs are formed. We conclude that an intermediate shear angle, $\le 40^\circ$, is needed for efficient particle acceleration via reconnection, and we propose a theoretical interpretation.Comment: 19 pages, 10 figure

The SEQanswers wiki: a wiki database of tools for high-throughput sequencing analysis

Recent advances in sequencing technology have created unprecedented opportunities for biological research. However, the increasing throughput of these technologies has created many challenges for data management and analysis. As the demand for sophisticated analyses increases, the development time of software and algorithms is outpacing the speed of traditional publication. As technologies continue to be developed, methods change rapidly, making publications less relevant for users. The SEQanswers wiki (SEQwiki) is a wiki database that is actively edited and updated by the members of the SEQanswers community (http://SEQanswers.com/). The wiki provides an extensive catalogue of tools, technologies and tutorials for high-throughput sequencing (HTS), including information about HTS service providers. It has been implemented in MediaWiki with the Semantic MediaWiki and Semantic Forms extensions to collect structured data, providing powerful navigation and reporting features. Within 2 years, the community has created pages for over 500 tools, with approximately 400 literature references and 600 web links. This collaborative effort has made SEQwiki the most comprehensive database of HTS tools anywhere on the web. The wiki includes task-focused mini-reviews of commonly used tools, and a growing collection of more than 100 HTS service providers. SEQwiki is available at: http://wiki.SEQanswers.com/