The Milky Way Tomography With SDSS. III. Stellar Kinematics

We study Milky Way kinematics using a sample of 18.8 million main-sequence stars with r 20 degrees). We find that in the region defined by 1 kpc < Z < 5 kpc and 3 kpc < R < 13 kpc, the rotational velocity for disk stars smoothly decreases, and all three components of the velocity dispersion increase, with distance from the Galactic plane. In contrast, the velocity ellipsoid for halo stars is aligned with a spherical coordinate system and appears to be spatially invariant within the probed volume. The velocity distribution of nearby (Z < 1 kpc) K/M stars is complex, and cannot be described by a standard Schwarzschild ellipsoid. For stars in a distance-limited subsample of stars (< 100 pc), we detect a multi-modal velocity distribution consistent with that seen by HIPPARCOS. This strong non-Gaussianity significantly affects the measurements of the velocity-ellipsoid tilt and vertex deviation when using the Schwarzschild approximation. We develop and test a simple descriptive model for the overall kinematic behavior that captures these features over most of the probed volume, and can be used to search for substructure in kinematic and metallicity space. We use this model to predict further improvements in kinematic mapping of the Galaxy expected from Gaia and the Large Synoptic Survey Telescope.NSF AST-615991, AST-0707901, AST-0551161, AST-02-38683, AST-06-07634, AST-0807444, PHY05-51164NASA NAG5-13057, NAG5-13147, NNXO-8AH83GPhysics Frontier Center/Joint Institute for Nuclear Astrophysics (JINA) PHY 08-22648U.S. National Science FoundationMarie Curie Research Training Network ELSA (European Leadership in Space Astrometry) MRTN-CT-2006-033481Fermi Research Alliance, LLC, United States Department of Energy DE-AC02-07CH11359Alfred P. Sloan FoundationParticipating InstitutionsJapanese MonbukagakushoMax Planck SocietyHigher Education Funding Council for EnglandMcDonald Observator

The Milky Way Tomography with SDSS: III. Stellar Kinematics

We study Milky Way kinematics using a sample of 18.8 million main-sequence stars with r<20 and proper-motion measurements derived from SDSS and POSS astrometry, including ~170,000 stars with radial-velocity measurements from the SDSS spectroscopic survey. Distances to stars are determined using a photometric parallax relation, covering a distance range from ~100 pc to 10 kpc over a quarter of the sky at high Galactic latitudes (|b|>20 degrees). We find that in the region defined by 1 kpc <Z< 5 kpc and 3 kpc <R< 13 kpc, the rotational velocity for disk stars smoothly decreases, and all three components of the velocity dispersion increase, with distance from the Galactic plane. In contrast, the velocity ellipsoid for halo stars is aligned with a spherical coordinate system and appears to be spatially invariant within the probed volume. The velocity distribution of nearby ($Z<1$ kpc) K/M stars is complex, and cannot be described by a standard Schwarzschild ellipsoid. For stars in a distance-limited subsample of stars (<100 pc), we detect a multimodal velocity distribution consistent with that seen by HIPPARCOS. This strong non-Gaussianity significantly affects the measurements of the velocity ellipsoid tilt and vertex deviation when using the Schwarzschild approximation. We develop and test a simple descriptive model for the overall kinematic behavior that captures these features over most of the probed volume, and can be used to search for substructure in kinematic and metallicity space. We use this model to predict further improvements in kinematic mapping of the Galaxy expected from Gaia and LSST.Comment: 90 pages, 26 figures, submitted to Ap

The Milky Way Tomography with SDSS: II. Stellar Metallicity

Using effective temperature and metallicity derived from SDSS spectra for ~60,000 F and G type main sequence stars (0.2<g-r<0.6), we develop polynomial models for estimating these parameters from the SDSS u-g and g-r colors. We apply this method to SDSS photometric data for about 2 million F/G stars and measure the unbiased metallicity distribution for a complete volume-limited sample of stars at distances between 500 pc and 8 kpc. The metallicity distribution can be exquisitely modeled using two components with a spatially varying number ratio, that correspond to disk and halo. The two components also possess the kinematics expected for disk and halo stars. The metallicity of the halo component is spatially invariant, while the median disk metallicity smoothly decreases with distance from the Galactic plane from -0.6 at 500 pc to -0.8 beyond several kpc. The absence of a correlation between metallicity and kinematics for disk stars is in a conflict with the traditional decomposition in terms of thin and thick disks. We detect coherent substructures in the kinematics--metallicity space, such as the Monoceros stream, which rotates faster than the LSR, and has a median metallicity of [Fe/H]=-0.96, with an rms scatter of only ~0.15 dex. We extrapolate our results to the performance expected from the Large Synoptic Survey Telescope (LSST) and estimate that the LSST will obtain metallicity measurements accurate to 0.2 dex or better, with proper motion measurements accurate to ~0.2 mas/yr, for about 200 million F/G dwarf stars within a distance limit of ~100 kpc (g<23.5). [abridged]Comment: 40 pages, 21 figures, emulateApJ style, accepted to ApJ, high resolution figures are available from http://www.astro.washington.edu/ivezic/sdss/mw/astroph0804.385

A horizon scan of issues affecting UK forest management within 50 years

Forests are in the spotlight: they are expected to play a pivotal role in our response to society’s greatest challenges, such as the climate and biodiversity crises. Yet, the forests themselves, and the sector that manages them, face a range of interrelated threats and opportunities. Many of these are well understood, even if the solutions remain elusive. However, there are also emerging trends that are currently less widely appreciated. We report here the results of a horizon scan to identify developing issues likely to affect UK forest management within the next 50 years. These are issues that are presently under-recognized but have potential for significant impact across the sector and beyond. As the forest management sector naturally operates over long timescales, the importance of using good foresight is self-evident. We followed a tried-and-tested horizon scanning methodology involving a diverse Expert Panel to collate and prioritize a longlist of 180 issues. The top 15 issues identified are presented in the Graphical Abstract. The issues represent a diverse range of themes, within a spectrum of influences from environmental shocks and perturbations to changing political and socio-economic drivers, with complex emerging interactions between them. The most highly ranked issue was ‘Catastrophic forest ecosystem collapse’, reflecting agreement that not only is such collapse a likely prospect but it would also have huge implications across the sector and wider society. These and many of the other issues are large scale, with far-reaching implications. We must be careful to avoid inaction through being overwhelmed, or indeed to merely focus on ‘easy wins’ without considering broader ramifications. Our responses to each of the challenges and opportunities highlighted must be synergistic and coherent, involving landscape-scale planning. A more adaptive approach to forest management will be essential, encouraging continual innovation and learning. The 15 horizon scan issues presented here are a starting point on which to build further research, prompt debate and action, and develop evidence-based policy and practice. We hope that this stimulates greater recognition of how our forests and sector may need to change to be fit for the future. In some cases, these changes will need to be fundamental and momentous

A horizon scan of issues affecting UK forest management within 50 years

Forests are in the spotlight: they are expected to play a pivotal role in our response to society’s greatest challenges, such as the climate and biodiversity crises. Yet, the forests themselves, and the sector that manages them, face a range of interrelated threats and opportunities. Many of these are well understood, even if the solutions remain elusive. However, there are also emerging trends that are currently less widely appreciated. We report here the results of a horizon scan to identify developing issues likely to affect UK forest management within the next 50 years. These are issues that are presently under-recognized but have potential for significant impact across the sector and beyond. As the forest management sector naturally operates over long timescales, the importance of using good foresight is self-evident. We followed a tried-and-tested horizon scanning methodology involving a diverse Expert Panel to collate and prioritize a longlist of 180 issues. The top 15 issues identified are presented in the Graphical Abstract. The issues represent a diverse range of themes, within a spectrum of influences from environmental shocks and perturbations to changing political and socio-economic drivers, with complex emerging interactions between them. The most highly ranked issue was ‘Catastrophic forest ecosystem collapse’, reflecting agreement that not only is such collapse a likely prospect but it would also have huge implications across the sector and wider society. These and many of the other issues are large scale, with far-reaching implications. We must be careful to avoid inaction through being overwhelmed, or indeed to merely focus on ‘easy wins’ without considering broader ramifications. Our responses to each of the challenges and opportunities highlighted must be synergistic and coherent, involving landscape-scale planning. A more adaptive approach to forest management will be essential, encouraging continual innovation and learning. The 15 horizon scan issues presented here are a starting point on which to build further research, prompt debate and action, and develop evidence-based policy and practice. We hope that this stimulates greater recognition of how our forests and sector may need to change to be fit for the future. In some cases, these changes will need to be fundamental and momentous

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Expanding Paramedicine in the Community (EPIC): study protocol for a randomized controlled trial

BACKGROUND: The incidence of chronic diseases, including diabetes mellitus (DM), heart failure (HF) and chronic obstructive pulmonary disease (COPD) is on the rise. The existing health care system must evolve to meet the growing needs of patients with these chronic diseases and reduce the strain on both acute care and hospital-based health care resources. Paramedics are an allied health care resource consisting of highly-trained practitioners who are comfortable working independently and in collaboration with other resources in the out-of-hospital setting. Expanding the paramedic’s scope of practice to include community-based care may decrease the utilization of acute care and hospital-based health care resources by patients with chronic disease. METHODS/DESIGN: This will be a pragmatic, randomized controlled trial comparing a community paramedic intervention to standard of care for patients with one of three chronic diseases. The objective of the trial is to determine whether community paramedics conducting regular home visits, including health assessments and evidence-based treatments, in partnership with primary care physicians and other community based resources, will decrease the rate of hospitalization and emergency department use for patients with DM, HF and COPD. The primary outcome measure will be the rate of hospitalization at one year. Secondary outcomes will include measures of health system utilization, overall health status, and cost-effectiveness of the intervention over the same time period. Outcome measures will be assessed using both Poisson regression and negative binomial regression analyses to assess the primary outcome. DISCUSSION: The results of this study will be used to inform decisions around the implementation of community paramedic programs. If successful in preventing hospitalizations, it has the ability to be scaled up to other regions, both nationally and internationally. The methods described in this paper will serve as a basis for future work related to this study. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02034045. Date: 9 January 2014. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1745-6215-15-473) contains supplementary material, which is available to authorized users

A comparison of copper(I) and copper(II) bound to thioether ligands : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Chemistry at Massey University

The structures of Cu(II) (DTH)2(BF4)2 (where DTH = 2,5-dithiahexane) and Cu(I) (DTO)2BF4 (where DTO = 3,6-dithiaoctane) have been investigated by single crystal X-ray diffraction techniques. After full matrix least squares refinement of the structures, with anisotropic temperature factors for all non hydrogen atoms in the Cu(II) structure, and for all atoms larger than fluorine in the Cu(I) structure, the conventional R factor converged to a final value of 0.057 for the Cu(II) structure, and 0.082 for the Cu(I) complex. The dark red crystals of the Cu(II) complex belong to the centrosymmetric monoclinic space group P2 1/c. with a = 8.082(3)Å, b = 10.282(3)Å, c = 11.893(4)Å and β = 115.3 degrees. Two dithiahexane ligands and two BF4-ions were found to co-ordinate to the Cu(II) ion to form a tetragonally distorted octahedron, with four Cu(II)-S bonds averaging 2.317Å in length, and two longer Cu(II)-F bonds averaging 2.576Å. The four sulphur atoms are part of two five membered Cu(II)-S-C-C-S rings in which both carbons are on the same side of the plane containing the copper and sulphur atoms. The colourless crystals of the Cu(I) complex were obtained in the non-centric orthorhombic space group Pna2 1, with a = 14.581(2)Å, b = 13.421(2)Å and c = 10.781(2)Å. The molecules exist as discrete monomeric species, with no co-ordination of the BF4- ion to the metal ion. The two ligand molecules co-ordinate to the Cu(I) ion to form a distorted tetrahedron, with the S-Cu(I)-S angles varying between 94.0 and 121.1 degrees. The four Cu(I)-S bonds average 2.307Å in length, and hence are approximately equal to the Cu(II)-S bonds (within experimental error). The two five membered Cu(I)-S-C-C-S rings are both in a gauche conformation, with one carbon below the plane containing the Cu(I) and S atoms, and the other above. The BF4- ion was disordered and was refined using rigid group restrictions. Cu-S co-ordination is thought to occur in some copper containing oxidation-reduction proteins. The observation of similar Cu-S bond distances when Cu(I) and Cu(II) are co-ordinated to thioether ligands (resembling the side chain of the amino acid methionine) may therefore be of direct relevance to the copper co-ordination in such proteins

The three dimensional structure of azurin, a blue copper protein, at 3Å resolution : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry at Massey University

Purifications and crystallizations of two electron transfer proteins, azurin and cytochrome c', from Alcaligenes denitrificans and Alcaligenes sp. NC1B 11015 have been carried out. The azurin crystals from Alcaligenes denitrificans were found suitable for high resolution X-ray structure analysis. They are orthorhombic, space group C2221 (with marked tetragonal pseudosymmetry), cell dimensions a = 75.0Å, b = 74.1Å, c = 99.5Å, with two molecules per asymmetric unit. A 3Å resolution electron density nap of azurin was calculated. Four isomorphous heavy atom derivatives, prepared with KAu(CN)2, uranyl acetate, Hg(NH3)2Cl2 and (KAu(CN)2 + uranyl acetate) (a double derivative) were used to calculate phases by the method of isomorphous replacement, giving an overall figure of merit of 0.614. The polypeptide chain could be followed unambiguously in both protein molecules in the asymmetric unit, with the aromatic sidechains, in particular, readily identifiable because of their distinctive appearance. Kendrew skeletal models were built for both molecules, the polypeptide chain (consisting of 129 amino acids) being found to be folded into an eight-strand β-barrel, with an additional flap containing a short helix. There is one disulphide bridge within the barrel. The topology of the molecule was found to be the same as that of plastocyanin, and a comparison of the three dimensional structures of azurin and plastocyanin allowed the sequences to be aligned on structural rather than purely statistical grounds. It also established the probability that the two proteins have evolved from a common ancestor. The copper atom has a highly-distorted tetrahedral co-ordination geometry, forming three shorter bonds (length approximately 2Å), with a cysteine thiolate sulphur (Cys 112) and two histidine imidazole nitrogens (His 46 and 117), as well as a longer bond (approximately 3Å) with a methionine thioether sulphur (Met 121). A surprising result was the closeness of a peptide carbonyl oxygen, that of Gly 45, to the copper atom. At this stage of the structure analysis it is not clear whether it should be regarded as a ligand, or not. Reduction of the protein crystals with chromous ions was attempted, and the results are discussed in terms of the possible electron transfer mechanism of the protein. The cytochrome c' crystals from both species of bacteria are hexagonal, space group P 6l22 (or P 6522), cell dimensions a = b = 54.7Å, c ~ 185Å γ = 120°, with one subunit (molecular weight 14,000) in the asymmetric unit. No structural work has been carried out on these