Planetary rover technology development requirements

Planetary surface (including lunar) mobility and sampling capability is required to support proposed future National Aeronautics and Space Administration (NASA) solar system exploration missions. The NASA Office of Aeronautics and Space Technology (OAST) is addressing some of these technology needs in its base research and development program, the Civil Space Technology Initiative (CSTI) and a new technology initiative entitled Pathfinder. The Pathfinder Planetary Rover (PPR) and Sample Acquisition, Analysis and Preservation (SAAP) programs will develop and validate the technologies needed to enable both robotic and piloted rovers on various planetary surfaces. The technology requirements for a planetary roving vehicle and the development plans of the PPR and SAAP programs are discussed

Characterizing mid-type M dwarfs in the Kepler field with the Discovery Channel Telescope and WIYN

Planet occurrence rates increase with decreasing stellar mass (later spectral types); therefore, M dwarf systems are our most promising targets in the search for exoplanets. The identification and characterization of stars in the original Kepler field was accomplished using photometry alone, resulting in large uncertainties for late-type stars like M dwarfs. In order to more accurately compute the planet occurrence rate around mid- type M dwarfs, we need to better constrain their stellar radii and masses, properties which strongly correlate with other stellar parameters such as temperature and metallicity. These measurements need to be performed on a statistically significant population of stars including systems with and without planets. Therefore, we have begun to spectroscopically characterize the properties of the 559 probable mid-type M dwarfs in the Kepler field using red optical spectra obtained with the DeVeny Spectrograph on the Discovery Channel Telescope (DCT) and Hydra on the WIYN telescope in order to constrain the planet occurrence rate for such stars. We will be presenting initial results from our DCT and WIYN observations, including new temperature, radius, and mass estimates which we can use in occurrence rate calculations.http://adsabs.harvard.edu/abs/2017AAS...22912608HPublished versio

Characterization of mid-type M dwarfs in the Kepler field

The planet occurrence rate has been found to increase with decreasing stellar mass (later spectral types) in the original Kepler field, and one out of four M dwarfs are expected to host Earth-sized planets within their habitable zones. M dwarf systems are, therefore, our most promising targets in the search for exoplanets. Yet the identification and characterization of M dwarfs in the Kepler field was accomplished using photometry alone and unfortunately this method provides large uncertainties for late-type stars. Notably absent from planet occurrence calculations are single planet mid-type M dwarfs (~M2-M6). In order to make an accurate calculation of the planet occurrence rate around mid-type M dwarfs, we need to constrain stellar radii and masses which depend on other stellar parameters (e.g. temperature and metallicity). We have identified 559 probable mid-type M dwarfs using photometric color selection criteria and have started to gather spectra of these objects in order to better constrain stellar properties and refine planet occurrence rates for this population. Here we outline the methods we are using for stellar classification and characterization and present some results from our initial data.http://adsabs.harvard.edu/abs/2016AAS...22743012HPublished versio

Regulation of Calmodulin- and Dopamine-Stimulated Adenylate Cyclase Activities by Light in Bovine Retina

Neural retina from most species contains 3,4-dihydroxyphenylethylamine (dopamine) receptors coupled to stimulation of adenylate cyclase activity. It has been demonstrated that release of dopamine from its neurons and subsequent occupation of dopamine receptors is increased by light. In this study, we have shown that adenylate cyclase activity in bovine retina is highly responsive to the endogenous Ca 2+ -binding protein, cal-modulin, and that calmodulin can increase dopamine-sen-sitive adenylate cyclase activity in bovine retina. We further demonstrate that both dopamine- and calmodulin-stimulated adenylate cyclase activities can be regulated by alterations in light. Bovine retinas were dissected from the eye under a low-intensity red safety light, defined as dark conditions, and incubated for 20 min in an oxygenated Krebs Henseleit buffer under either dark or light conditions. The retinas were then homogenized and adenylate cyclase activity measured in a paniculate fraction washed to deplete it of endogenous Ca 2+ and calmodulin. Activation of adenylate cyclase activity by calmodulin, dopamine, and the nonhydrolyzable GTP analog, gua-nosine-5′-(Β,Γ-imido)triphosphate (GppNHp), was significantly (60%) greater in paniculate fractions from retinas that had been incubated under dark conditions as compared to those incubated under light conditions. Basal, Mn 2+ -, and GTP-stimulated adenylate cyclase activities were not altered by changes in lighting conditions. Calmodulin could increase the maximum stimulation of adenylate cyclase by dopamine in retinas incubated under either dark or light conditions, but the degree of its effect was greater in retinas incubated under light conditions. Activation of adenylate cyclase by calmodulin, dopamine, and GppNHp in paniculate fractions from retinas incubated under light conditions was indistinguishable from the activation obtained when retinas were incubated in the dark in the presence of exogenous dopamine. These results suggest that an increased release of dopamine occurs in light. The decreased response of adenylate cyclase to exogenous dopamine can then be explained by a subsequent down-regulation of dopamine receptor activity. The down-regulation of dopamine receptor activity can also regulate activation of adenylate cyclase by GppNHp and calmodulin. The results suggest that dopamine, calmodulin, and GppNHp are modulators of a common component of adenylate cyclase activity, and this component is regulated by light.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66410/1/j.1471-4159.1984.tb12753.x.pd

On the Eigenvalue Density of Real and Complex Wishart Correlation Matrices

Wishart correlation matrices are the standard model for the statistical analysis of time series. The ensemble averaged eigenvalue density is of considerable practical and theoretical interest. For complex time series and correlation matrices, the eigenvalue density is known exactly. In the real case, however, a fundamental mathematical obstacle made it forbidingly complicated to obtain exact results. We use the supersymmetry method to fully circumvent this problem. We present an exact formula for the eigenvalue density in the real case in terms of twofold integrals and finite sums.Comment: 4 pages, 2 figure

The applicability of Raman spectroscopy in the assessment of palaeowildfire intensity

Acknowledgments We would like to thank Maria-Ara Carballo-Meilan, Ilse Kamerling and Colin Taylor for their kind assistance with the procurement and operation of pyrolysis equipment. The use of Calluna vulgaris material in this study was informed under an assessment of ‘least concern’ by the IUCN Red List of Threatened Species. This research was supported by funds from the School of Geosciences, University of Aberdeen.Peer reviewedPostprin

M-Dwarf Fast Rotators and the Detection of Relatively Young Multiple M-Star Systems

We have searched the Kepler light curves of ~3900 M-star targets for evidence of periodicities that indicate, by means of the effects of starspots, rapid stellar rotation. Several analysis techniques, including Fourier transforms, inspection of folded light curves, 'sonograms', and phase tracking of individual modulation cycles, were applied in order to distinguish the periodicities due to rapid rotation from those due to stellar pulsations, eclipsing binaries, or transiting planets. We find 178 Kepler M-star targets with rotation periods, P_rot, of < 2 days, and 110 with P_rot < 1 day. Some 30 of the 178 systems exhibit two or more independent short periods within the same Kepler photometric aperture, while several have three or more short periods. Adaptive optics imaging and modeling of the Kepler pixel response function for a subset of our sample support the conclusion that the targets with multiple periods are highly likely to be relatively young physical binary, triple, and even quadruple M star systems. We explore in detail the one object with four incommensurate periods all less than 1.2 days, and show that two of the periods arise from one of a close pair of stars, while the other two arise from the second star, which itself is probably a visual binary. If most of these M-star systems with multiple periods turn out to be bound M stars, this could prove a valuable way of discovering young hierarchical M-star systems; the same approach may also be applicable to G and K stars. The ~5% occurrence rate of rapid rotation among the ~3900 M star targets is consistent with spin evolution models that include an initial contraction phase followed by magnetic braking, wherein a typical M star can spend several hundred Myr before spinning down to periods longer than 2 days.Comment: 17 pages, 12 figures, 2 tables; accepted for publication in The Astrophysical Journa

mPUMA: a computational approach to microbiota analysis by de novo assembly of operational taxonomic units based on protein-coding barcode sequences.

BACKGROUND: Formation of operational taxonomic units (OTU) is a common approach to data aggregation in microbial ecology studies based on amplification and sequencing of individual gene targets. The de novo assembly of OTU sequences has been recently demonstrated as an alternative to widely used clustering methods, providing robust information from experimental data alone, without any reliance on an external reference database. RESULTS: Here we introduce mPUMA (microbial Profiling Using Metagenomic Assembly, http://mpuma.sourceforge.net), a software package for identification and analysis of protein-coding barcode sequence data. It was developed originally for Cpn60 universal target sequences (also known as GroEL or Hsp60). Using an unattended process that is independent of external reference sequences, mPUMA forms OTUs by DNA sequence assembly and is capable of tracking OTU abundance. mPUMA processes microbial profiles both in terms of the direct DNA sequence as well as in the translated amino acid sequence for protein coding barcodes. By forming OTUs and calculating abundance through an assembly approach, mPUMA is capable of generating inputs for several popular microbiota analysis tools. Using SFF data from sequencing of a synthetic community of Cpn60 sequences derived from the human vaginal microbiome, we demonstrate that mPUMA can faithfully reconstruct all expected OTU sequences and produce compositional profiles consistent with actual community structure. CONCLUSIONS: mPUMA enables analysis of microbial communities while empowering the discovery of novel organisms through OTU assembly

Revision of failed hip resurfacing to total hip arthroplasty rapidly relieves pain and improves function in the early post operative period

We reviewed the results of 25 consecutive patients who underwent revision of a hip resurfacing prosthesis to a total hip replacement. Revisions were performed for recurrent pain and effusion, infection and proximal femoral fractures. Both components were revised in 20 cases