Lithology and Internal Structure of the San Andreas Fault at Depth Based on Characterization of Phase 3 Whole-rock Core in the San Andreas Fault Observatory at Depth (SAFOD) Borehole

We characterize the lithology and structure of the spot core obtained in 2007 during Phase 3 drilling of the San Andreas Fault Observatory at Depth (SAFOD) in order to determine the composition, structure, and deformation processes of the fault zone at 3 km depth where creep and microseismicity occur. A total of approximately 41 m of spot core was taken from three separate sections of the borehole; the core samples consist of fractured arkosic sandstones and shale west of the SAF zone (Pacific Plate) and sheared fine-grained sedimentary rocks, ultrafine black fault-related rocks, and phyllosilicate-rich fault gouge within the fault zone (North American Plate). The fault zone at SAFOD consists of a broad zone of variably damaged rock containing localized zones of highly concentrated shear that often juxtapose distinct protoliths. Two zones of serpentinite-bearing clay gouge, each meters-thick, occur at the two locations of aseismic creep identified in the borehole on the basis of casing deformation. The gouge primarily is comprised of Mg-rich clays, serpentinite (lizardite ± chrysotile) with notable increases in magnetite, and Ni-Cr-oxides/hydroxides relative to the surrounding host rock. The rocks surrounding the two creeping gouge zones display a range of deformation including fractured protolith, block-in-matrix, and foliated cataclasite structure. The blocks and clasts predominately consist of sandstone and siltstone embedded in a clay-rich matrix that displays a penetrative scaly fabric. Mineral alteration, veins and fracture-surface coatings are present throughout the core, and reflect a long history of syn-deformation, fluid-rock reaction that contributes to the low-strength and creep in the meters-thick gouge zones

Swift observations of the SFXT SAX J1818.6-1703 in outburst

We present the Swift observations of the supergiant fast X-ray transient (SFXT) SAX J1818.6-1703 collected during the most recent outburst, which occurred on May 6 2009. In particular, we present broad-band spectroscopic and timing analysis as well as a Swift/XRT light curve that spans more than two weeks of observations. The broad-band spectral models and length of the outburst resemble those of the prototype of the SFXT class, XTE J1739-302, further confirming SAX J1818.6-1703 as a member of this class.Comment: Proceedings of 'X-Ray Astronomy 2009, Present Status, multiwavelength approach and future perspectives', September 7 - 11, 2009, Bologna, Ital

Optical Geolocation for Small Unmanned Aerial Systems

This paper presents an airborne optical geolocation system using four optical targets to provide position and attitude estimation for a sUAS supporting the NASA Acoustic Research Mission (ARM), where the goal is to reduce nuisance airframe noise during approach and landing. A large precision positioned microphone array captures the airframe noise for multiple passes of a Gulfstream III aircraft. For health monitoring of the microphone array, the Acoustic Calibration Vehicle (ACV) sUAS completes daily flights with an onboard speaker emitting tones at frequencies optimized for determining microphone functionality. An accurate position estimate of the ACV relative to the array is needed for microphone health monitoring. To this end, an optical geolocation system using a downward facing camera mounted to the ACV was developed. The 3D positioning of the ACV is computed using the pinhole camera model. A novel optical geolocation algorithm first detects the targets, then a recursive algorithm tightens the localization of the targets. Finally, the position of the sUAS is computed using the image coordinates of the targets, the 3D world coordinates of the targets, and the camera matrix. A Real-Time Kinematic GPS system is used to compare the optical geolocation system

Atypical expression of smooth muscle markers and co-activators and their regulation in rheumatic aortic and calcified bicuspid valves

Objective: We have previously reported that human calcified aortic cusps have abundant expression of smooth muscle (SM) markers and co-activators. We hypothesised that cells in bicuspid aortic valve (BAV) cusps and those affected by rheumatic heart valve (RHV) disease may follow a similar phenotypic transition into smooth muscle cells, a process that could be regulated by transforming growth factors (TGFs). Aims: Cusps from 8 patients with BAV and 7 patients with RHV were analysed for ealy and late SM markers and regulators of SM gene expression by immunocytochemistry and compared to healthy aortic valves from 12 unused heart valve donors. The ability of TGFs to induce these markers in valve endothelial cells (VECs) on two substrates was assessed. Results: 7 out of 8 BAVs and all the RHVs showed an increased and atypical expression of early and late SM markers α-SMA, calponin, SM22 and SM-myosin. The SM marker coactivators were aberrantly expressed in 6 of the BAV and 6 of the RHV, in a similar regional pattern to the expression of SM markers. Additionally, regions of VECs, and endothelial cells lining the vessels within the cusps were found to be positive for SM markers and coactivators in 3 BAV and 6 RHV. Both BAVs and RHVs were significantly thickened and HIF1α expression was prominent in 4 BAVs and 1 RHV. The ability of TGFβs to induce the expression of SM markers and myocardin was greater in VECs cultured on fibronectin than on gelatin. Fibronectin was shown to be upregulated in BAVs and RHVs, within the cusps as well as in the basement membrane. Conclusion: BAVs and RHVs expressed increased numbers of SM marker-positive VICs and VECs. Concomittantly, these cells expressed MRTF-A and myocardin, key regulators of SM gene expression. TGFβ1 was able to preferentially upregulate SM markers and myocardin in VECs on fibronectin, and fibronectin was found to be upregulated in BAVs and RHVs. These findings suggest a role of VEC as a source of cells that express SM cell markers in BAVs and RHVs. The similarity between SM marker expression in BAVs and RHVs with our previous study with cusps from patients with aortic stenosis suggests the existance of a common pathological pathway between these different pathologies. Abbreviations: BAV, bicuspid aortic valve; RHV, rheumatic heart valve; SM, smooth muscle; TGF, transforming growth factor; MRTF-A, myocardin related transcription factor A; VIC, valve interstitial cell; VEC, valve endothelial cell; PCNA, proliferating nuclear cell antigen; HIF1α, hypoxia inducible factor 1α

Examining the relationship between work-related factors and work-family-related factors on work-family conflict

The current work-family conflict literature is characterized by limitations in focus and methodology, particularly with a failure to link work-family conflict with work-family policies. This study compares the influence of work-related factors and work-family related factors on work-family conflict in two directions. A local government organization in New Zealand was the setting. Findings show that work factors account for a significant component of both work-to-family and family-to-work conflict, although this is far greater on work-family conflict. Work-family practice use had little influence on work-family practices was found to positively associate with family-work conflict. Overall, the finds suggest managers in search of reducing employee conflict should focus directly upon work factors such as workload, rather than see to use work-family practices as the primary way to reduce conflict

Systems Analysis of complex glaciological processes and application to calving of Amery Ice Shelf, East Antarctica

Calving is a complex process subject to several cooperating atmospheric, oceanographic and glaciological forcings that vary in space and time, and whose relative effects are challenging to separate. Statistical ‘Systems Analysis’ is commonly used in engineering and economics to extricate complex ‘force–response’ relationships. Here we apply Systems Analysis to the Amery rift system, East Antarctica. We develop a scalable ‘System Model’ driven by a coarsely-sampled dataset characteristic of glaciological observations in remote locations, and validate it using rift lengths observed in 2000–06 and 2012. In this initial demonstration, we forecast a detachment date of ∼2019 ± 5 years for the large tabular iceberg colloquially known as the ‘Loose Tooth’, for which relative humidity surprisingly emerges as the best statistical predictor. RACMO2 climate modelling reveals that relative humidity correlates best with surface albedo and snowmelt, both of which are intimately linked to firn compaction and ice shelf temperature and flow. We postulate that relative humidity can therefore serve as a proxy for internal stress, a known key control of ‘Loose Tooth’ calving. Although no physical causality is implied in Systems Analysis, postulates such as this can aid in setting priorities in studies of complex glaciological processes

Uniform approximation for the overlap caustic of a quantum state with its translations

The semiclassical Wigner function for a Bohr-quantized energy eigenstate is known to have a caustic along the corresponding classical closed phase space curve in the case of a single degree of freedom. Its Fourier transform, the semiclassical chord function, also has a caustic along the conjugate curve defined as the locus of diameters, i.e. the maximal chords of the original curve. If the latter is convex, so is its conjugate, resulting in a simple fold caustic. The uniform approximation through this caustic, that is here derived, describes the transition undergone by the overlap of the state with its translation, from an oscillatory regime for small chords, to evanescent overlaps, rising to a maximum near the caustic. The diameter-caustic for the Wigner function is also treated.Comment: 14 pages, 9 figure

Bose-Einstein Condensation in a Harmonic Potential

We examine several features of Bose-Einstein condensation (BEC) in an external harmonic potential well. In the thermodynamic limit, there is a phase transition to a spatial Bose-Einstein condensed state for dimension D greater than or equal to 2. The thermodynamic limit requires maintaining constant average density by weakening the potential while increasing the particle number N to infinity, while of course in real experiments the potential is fixed and N stays finite. For such finite ideal harmonic systems we show that a BEC still occurs, although without a true phase transition, below a certain ``pseudo-critical'' temperature, even for D=1. We study the momentum-space condensate fraction and find that it vanishes as 1/N^(1/2) in any number of dimensions in the thermodynamic limit. In D less than or equal to 2 the lack of a momentum condensation is in accord with the Hohenberg theorem, but must be reconciled with the existence of a spatial BEC in D=2. For finite systems we derive the N-dependence of the spatial and momentum condensate fractions and the transition temperatures, features that may be experimentally testable. We show that the N-dependence of the 2D ideal-gas transition temperature for a finite system cannot persist in the interacting case because it violates a theorem due to Chester, Penrose, and Onsager.Comment: 34 pages, LaTeX, 6 Postscript figures, Submitted to Jour. Low Temp. Phy