The Galactic Disk-Halo transition - Evidence from Stellar Abundances

New information on the relations between the Galactic disks, the halo, and satellite galaxies is being obtained from elemental abundances of stars having metallicities in the range -1.5 < [Fe/H] < -0.5. The first results for a sample of 26 halo stars and 13 thick-disk stars observed with the ESO VLT/UVES spectrograph are presented. The halo stars fall in two distinct groups: One group (9 stars) has [alpha/Fe]= 0.30 +-0.03 like the thick-disk stars. The other group (17 stars) shows a clearly deviating trend ranging from [alpha/Fe]= 0.20 at [Fe/H]= -1.3 to [alpha/Fe]= 0.08 at [Fe/H]= -0.8. The kinematics of the stars are discussed and the abundance ratios Na/Fe, Ni/Fe, Cu/Fe and Ba/Y are applied to see if the low-alpha stars are connected to the thin disk or to Milky Way satellite galaxies. Furthermore, we compare our data with simulations of chemical abundance distributions in hierarchically formed stellar halos in a LambdaCDM Universe.Comment: 6 pages, 6 figures. To appear in proceedings of the IAU Symposium No. 254 "The Galaxy Disk in Cosmological Context", Copenhagen 9-13 June 2008, Eds. J. Andersen, J.Bland-Hawthorn & B. Nordstrom, Cambridge University Pres

Strain Partitioning and Frictional Behavior of Opalinus Clay During Fault Reactivation

The Opalinus Clay (OPA) formation is considered a suitable host rock candidate for nuclear waste storage. However, the sealing integrity and long-term safety of OPA are potentially compromised by pre-existing natural or artificially induced faults. Therefore, characterizing the mechanical behavior and microscale deformation mechanisms of faults and the surrounding rock is relevant for predicting repository damage evolution. In this study, we performed triaxial tests using saw-cut samples of the shaly and sandy facies of OPA to investigate the influence of pressure and mineral composition on the deformation behavior during fault reactivation. Dried samples were hydrostatically pre-compacted at 50 MPa and then deformed at constant strain rate, drained conditions and confining pressures (pc) of 5–35 MPa. Mechanical data from triaxial tests was complemented by local strain measurements to determine the relative contribution of bulk deformation and fault slip, as well as by acoustic emission (AE) monitoring, and elastic P-wave velocity measurements using ultrasonic transmissions. With increasing pc, we observe a transition from brittle deformation behavior with highly localized fault slip to semi-brittle behavior characterized by non-linear strain hardening with increasing delocalization of deformation. We find that brittle localization behavior is limited by pc at which fault strength exceeds matrix yield strength. AEs were only detected in tests performed on sandy facies samples, and activity decreased with increasing pc. Microstructural analysis of deformed samples revealed a positive correlation between increasing pc and gouge layer thickness. This goes along with a change from brittle fragmentation and frictional sliding to the development of shear zones with a higher contribution of cataclastic and granular flow. Friction coefficient at fault reactivation is only slightly higher for the sandy (µ ~ 0.48) compared to the shaly facies (µ ~ 0.4). Slide-hold-slide tests performed after ~ 6 mm axial shortening suggest stable creeping and long-term weakness of faults at the applied conditions. Our results demonstrate that the mode of fault reactivation highly depends on the present stress field and burial history

Design and Analysis of Outer Mold Line Close-outs for the Max Launch Abort System (MLAS) Flight Experiment

In 2007, the NASA Exploration Systems Mission Directorate (ESMD) chartered the NASA Engineering Safety Center (NESC) to demonstrate an alternate launch abort concept as risk mitigation for the Orion project's baseline "tower" design. On July 8, 2009, a full scale, passive aerodynamically stabilized Max Launch Abort System (MLAS) pad abort demonstrator was successfully launched from NASA Goddard Space Flight Center's Wallops Flight Facility. Aerodynamic close-outs were required to cover openings on the MLAS fairing to prevent aerodynamic flow-through and to maintain the MLAS OML surface shape. Two-ply duct tape covers were designed to meet these needs. The duct tape used was a high strength fiber reinforced duct tape with a rubberized adhesive that demonstrated 4.6 lb/in adhesion strength to the unpainted fiberglass fairing. Adhesion strength was observed to increase as a function of time. The covers were analyzed and experimentally tested to demonstrate their ability to maintain integrity under anticipated vehicle ascent pressure loads and to not impede firing of the drogue chute mortars. Testing included vacuum testing and a mortar fire test. Tape covers were layed-up on thin Teflon sheets to facilitate installation on the vehicle. Custom cut foam insulation board was used to fill mortar hole and separation joint cavities and provide support to the applied tape covers. Flight test results showed that the tape covers remained adhered during flight

Akustisk sensor for fangstkontroll i notfiske - Spesifikasjoner for montering og bruk

Fangst- og redskapsovervåking gir kontroll over fangstprosessen og kan bidra til å redusere utilsiktet dødelighet og gi et mer målrettet og effektivt fiske. I prosjekt «Fangstkontroll i notfiske etter pelagiske arter» (FHF 901350) har vi undersøkt ulike akustiske metoder for fangstovervåking under notfiske. I denne rapporten presenterer vi forsøk der vi har tilpasset Simrads fangstkontrollsystem utviklet hovedsakelig for trål til fiske med snurpenot. De trådløse sensorene har et innebygget ekkolodd som informerer skipperen om fangstmengde i trålen. Vi har undersøkt om sensorene med noen tilpasninger til fiske med not kan gi like nyttig informasjon om fangstmengde og fiskens posisjon i nota. Resultatene viser at det gjenstår arbeid før systemet kan være en praktisk og nyttig løsning. Likevel har det helt klart potensial. God kontakt mellom sensor og hydrofon oppnås ved å ha hydrofon dypere i vannet. Stabil og robust montering av sensorer, fungerte best med sensor festet på nota noen meter under flåen, men også i snurperingene nederst i nota. Det var antydning til identifikasjon av fisk på ekkoloddene. Spørsmålet er om ekkoloddet i notsensoren har bra nok oppløsning for identifisering av fangst eller om det må vurderes flere smalere stråler istedenfor en bred stråle. I rapporten gir vi anbefalinger for montering og bruk av notsensor samt forslag til videre utviklingsarbeid.publishedVersio

Beliefs and Attitudes toward Boating of Four Stakeholder Groups in the Saranac Lake Area

Public natural resource management agencies work with diverse stakeholder groups such as business owners, visitors, and landowners as they implement visitor management policies. This study focuses on the attitudes and beliefs of four stakeholder groups in relation to the use of non-motorized boats, motorized boats, and personal watercraft (e.g., jet Skis) on water bodies in the Saranac Lakes Wild Forest of New York State\u27s Adirondack Park. A mixed-methods approach including land manager interviews and stakeholder surveys was used. Interview results were the basis for the questionnaire used in mail surveys of shoreline and inland landowners, business owners, and campers. Analysis of variance indicated significant differences among the four stakeholder groups concerning beliefs and attitudes toward non-motorized and motorized boat use, but no significant differences in beliefs and attitudes toward personal watercraft use

Targeted Resequencing and Analysis of the Diamond-Blackfan Anemia Disease Locus RPS19

BACKGROUND: The Ribosomal protein S19 gene locus (RPS19) has been linked to two kinds of red cell aplasia, Diamond-Blackfan Anemia (DBA) and Transient Erythroblastopenia in Childhood (TEC). Mutations in RPS19 coding sequences have been found in 25% of DBA patients, but not in TEC patients. It has been suggested that non-coding RPS19 sequence variants contribute to the considerable clinical variability in red cell aplasia. We therefore aimed at identifying non-coding variations associated with DBA or TEC phenotypes. METHODOLOGY/PRINCIPAL FINDINGS: We targeted a region of 19'980 bp encompassing the RPS19 gene in a cohort of 89 DBA and TEC patients for resequencing. We provide here a catalog of the considerable, previously unrecognized degree of variation in this region. We identified 73 variations (65 SNPs, 8 indels) that all are located outside of the RPS19 open reading frame, and of which 67.1% are classified as novel. We hypothesize that specific alleles in non-coding regions of RPS19 could alter the binding of regulatory proteins or transcription factors. Therefore, we carried out an extensive analysis to identify transcription factor binding sites (TFBS). A series of putative interaction sites coincide with detected variants. Sixteen of the corresponding transcription factors are of particular interest, as they are housekeeping genes or show a direct link to hematopoiesis, tumorigenesis or leukemia (e.g. GATA-1/2, PU.1, MZF-1). CONCLUSIONS: Specific alleles at predicted TFBSs may alter the expression of RPS19, modify an important interaction between transcription factors with overlapping TFBS or remove an important stimulus for hematopoiesis. We suggest that the detected interactions are of importance for hematopoiesis and could provide new insights into individual response to treatment