The envirome and the connectome: exploring the structural noise in the human brain associated with socioeconomic deprivation

Complex cognitive functions are widely recognized to be the result of a number of brain regions working together as large-scale networks. Recently, complex network analysis has been used to characterize various structural properties of the large scale network organization of the brain. For example, the human brain has been found to have a modular architecture i.e. regions within the network form communities (modules) with more connections between regions within the community compared to regions outside it. The aim of this study was to examine the modular and overlapping modular architecture of the brain networks using complex network analysis. We also examined the association between neighborhood level deprivation and brain network structure – modularity and grey nodes. We compared network structure derived from anatomical MRI scans of 42 middle-aged neurologically healthy men from the least (LD) and the most deprived (MD) neighborhoods of Glasgow with their corresponding random networks. Cortical morphological covariance networks were constructed from the cortical thickness derived from the MRI scans of the brain. For a given modularity threshold, networks derived from the MD group showed similar number of modules compared to their corresponding random networks, while networks derived from the LD group had more modules compared to their corresponding random networks. The MD group also had fewer grey nodes – a measure of overlapping modular structure. These results suggest that apparent structural difference in brain networks may be driven by differences in cortical thicknesses between groups. This demonstrates a structural organization that is consistent with a system that is less robust and less efficient in information processing. These findings provide some evidence of the relationship between socioeconomic deprivation and brain network topology

Retrospective Barrier Placements for a Skunk Rabies Epizootic in NW Wyoming

Striped skunks (Mephitis mephitis) are the most important reservoir of rabies on the Great Plains. In August, 1988 a skunk rabies epizootic proceeded from the index case west of Cowley, WY. By 1991, epizootic had reached nearly all areas in the Shoshone River Basin (SRB), and it ended in 1993. This area and the remainder of the SRB had been previously considered rabies-free. The USDA\u27s Wildlife Services (WS) cooperated with state and local officials in a rabies monitoring and control program starting in 1990. Using information from the literature, signs, tracks, and radio-telemetry of normal and rabid skunks, WS decided to trap mainly riparian and irrigated agricultural habitats in the valley\u27s floor. Here, a mosaic of irrigation ditches (e.g., Buffalo Bill Cody\u27s circa 1908) was shown to be travel corridors for skunks. Trapped species (\u3e1,000 skunks) were sent to the Wyoming State Veterinary Laboratory for rabies testing using immuno-fluorescent of brain tissues. The study area extended from the Bighorn Canyon and Lake on the east up river to Buffalo Bill Reservoir on the west. The study area and subsequent epizootic encompassed a portion of the Shoshone River ~90 km in length and an area of ~ 85,000 ha (54 mi2). Traditional surveillance data composed \u3c10% of the sample -public referrals of suspiciously acting wildlife and road kills. We analyzed 215 rabid skunk locations and dates together with GIS hydrology and land use information. Hypothetical barriers were modeled using potential synergisms formed among restricted habitat, depopulation, and vaccine (if one had been available), combined with the natural epizootiology of this rabies strain with high virulence. Two dates for barrier locations were identified that may have halted the spreading epizootic: 1) before April 1989, when the rabies epizootic might have been limited to Polecat and Sage Creeks, and 2) June 1989, when the epizootic may have been stopped before it entered the majority of SRB including the larger population centers of Byron, Powell, and Cody

Retrospective Barrier Placements for a Skunk Rabies Epizootic in NW Wyoming

Striped skunks (Mephitis mephitis) are the most important reservoir of rabies on the Great Plains. In August, 1988 a skunk rabies epizootic proceeded from the index case west of Cowley, WY. By 1991, epizootic had reached nearly all areas in the Shoshone River Basin (SRB), and it ended in 1993. This area and the remainder of the SRB had been previously considered rabies-free. The USDA\u27s Wildlife Services (WS) cooperated with state and local officials in a rabies monitoring and control program starting in 1990. Using information from the literature, signs, tracks, and radio-telemetry of normal and rabid skunks, WS decided to trap mainly riparian and irrigated agricultural habitats in the valley\u27s floor. Here, a mosaic of irrigation ditches (e.g., Buffalo Bill Cody\u27s circa 1908) was shown to be travel corridors for skunks. Trapped species (\u3e1,000 skunks) were sent to the Wyoming State Veterinary Laboratory for rabies testing using immuno-fluorescent of brain tissues. The study area extended from the Bighorn Canyon and Lake on the east up river to Buffalo Bill Reservoir on the west. The study area and subsequent epizootic encompassed a portion of the Shoshone River ~90 km in length and an area of ~ 85,000 ha (54 mi2). Traditional surveillance data composed \u3c10% of the sample -public referrals of suspiciously acting wildlife and road kills. We analyzed 215 rabid skunk locations and dates together with GIS hydrology and land use information. Hypothetical barriers were modeled using potential synergisms formed among restricted habitat, depopulation, and vaccine (if one had been available), combined with the natural epizootiology of this rabies strain with high virulence. Two dates for barrier locations were identified that may have halted the spreading epizootic: 1) before April 1989, when the rabies epizootic might have been limited to Polecat and Sage Creeks, and 2) June 1989, when the epizootic may have been stopped before it entered the majority of SRB including the larger population centers of Byron, Powell, and Cody

Identifying Young Brown Dwarfs Using Gravity-Sensitive Spectral Features

We report the initial results of the Brown Dwarf Spectroscopic Survey Gravity Project, to study gravity sensitive features as indicators of youth in brown dwarfs. Low-resolution (R~2000) J-band and optical (R~1000) observations using NIRSPEC and LRIS at the W.M. Keck Observatory reveal transitions of TiO, VO, K I, Na I, Cs I, Rb I, CaH, and FeH. By comparing these features in late-type giants and in old field dwarfs we show that they are sensitive to the gravity (g = GM/R^2) of the object. Using low-gravity spectral signatures as age indicators, we observed and analyzed J-band and optical spectra of two young brown dwarfs, G 196-3B (20-300 Myr) and KPNO Tau-4 (1-2 Myr), and two possible low mass brown dwarfs in the sigma Orionis cluster (3-7 Myr). We report the identification of the phi bands of TiO near 1.24 microns and the A-X band of VO near 1.18 microns together with extremely weak J-band lines of K I in KPNO-Tau4. This is the first detection of TiO and VO in the J-band in a sub-stellar mass object. The optical spectrum of KPNO-Tau4 exhibits weak K I and Na I lines, weak absorption by CaH, and strong VO bands, also signatures of a lower gravity atmosphere. G 196-3B shows absorption features in both wavelength regions like those of KPNO-Tau4 suggesting that its age and mass are at the lower end of published estimates. Whereas sigma Ori 51 appears to be consistent with a young sub-stellar object, sigma Ori 47 shows signatures of high gravity most closely resembling an old L1.5/L0, and can not be a member of the sigma Orionis cluster.Comment: 14 pages, 4 figures. To appear in the January 10, 2004 issue of the Astrophysical Journa

Biological Records Centre Annual Report 2005-2006

The period covered by this report is the first year of a new six-year partnership between CEH and JNCC. For this period, there is increased emphasis on targeted survey, on analysis and interpretation and on communications and outreach. These activities were always part of BRC’s work, but they have been given greater prominence as a result of rapid developments in information technology. Data are increasingly reaching BRC in electronic form, so that the effort of data entry and collation is reduced. The data, collected by many volunteers and then collated and analysed at BRC, document the changing status and distribution of plants and animals in Britain. Distribution maps are published in atlases and are available via the internet through the NBN Gateway. The effects of change or loss of habitats, the influence of climate change and the consequences of changing water quality are all examples of the environmental factors that affect our biodiversity and which BRC aims to document and understand. The results are vital for developing environmental policies, to support conservation, and for fundamental ecological research. BRC is funded jointly by JNCC and NERC through a partnership based on a Memorandum of Agreement (MoA). The partnership started in 1973 when the Nature Conservancy was divided to form the successor bodies Nature Conservancy Council (NCC) and Institute of Terrestrial Ecology (ITE). NCC was in turn divided further to form JNCC and three Country Agencies, while ITE was merged with other NERC units to form CEH. Through all these changes, the partnership has been maintained. A six-year memorandum of agreement ended on 31 January 2005 (Hill et al. 2005). The present report covers the first full year, 2005-6, of the new agreement for 2005-2010. Rapid progress in information technology continues to be highly beneficial for BRC, whose data are increasingly used by the UK country conservation agencies, environmental consultants, NGOs, research workers, policy makers and volunteers. It is gratifying to know that, through our ability to display data on the National Biodiversity Network (NBN) Gateway, some of our data suppliers now have immediate access to their own data in a convenient form. The year 2005-6 has been one of steady progress, with new datasets added to BRC, substantial additions to existing data, and improved communication with the NBN Gateway. The most high profile activity of the year has been the Harlequin Ladybird Survey, which has enabled us to observe the early stages of colonization by a mobile insect in greater detail than has been possible in any previous case

Using AI/expert system technology to automate planning and replanning for the HST servicing missions

This paper describes a knowledge-based system that has been developed to automate planning and scheduling for the Hubble Space Telescope (HST) Servicing Missions. This new system is the Servicing Mission Planning and Replanning Tool (SM/PART). SM/PART has been delivered to the HST Flight Operations Team (FOT) at Goddard Space Flight Center (GSFC) where it is being used to build integrated time lines and command plans to control the activities of the HST, Shuttle, Crew and ground systems for the next HST Servicing Mission. SM/PART reuses and extends AI/expert system technology from Interactive Experimenter Planning System (IEPS) systems to build or rebuild time lines and command plans more rapidly than was possible for previous missions where they were built manually. This capability provides an important safety factor for the HST, Shuttle and Crew in case unexpected events occur during the mission

The NIRSPEC Brown Dwarf Spectroscopic Survey. I. Low-Resolution Near-Infrared Spectra

We present the first results of a near-infrared (0.96-2.31 micron) spectroscopic survey of M, L, and T dwarfs obtained with NIRSPEC on the Keck II telescope. Our new survey has a resolving power of R = 2000 and is comprised of two major data sets: 53 J-band (1.14-1.36 micron) spectra covering all spectral types from M6 to T8 with at least two members in each spectral subclass (wherever possible), and 25 flux-calibrated spectra from 1.14 to 2.31 microns for most spectral classes between M6 and T8. Sixteen of these 25 objects have additional spectral coverage from 0.96-1.14 microns to provide overlap with optical spectra. Spectral flux ratio indexes for prominent molecular bands are derived and equivalent widths (EWs) for several atomic lines are measured. We find that a combination of four H2O and two CH4 band strengths can be used for spectral classification. Weak (EW~1-2 angstrom) atomic lines of Al I and Ca I disappear at the boundary between M and L types.Comment: 60 pages, 25 figures. To appear in the Astrophysical Journal Vol 596. Received 2003 March 31; accepted 2003 June 20. Web site at http://www.astro.ucla.edu/~mclean/BDSSarchiv

Surface Gravities for 228 M, L, and T Dwarfs in the NIRSPEC Brown Dwarf Spectroscopic Survey

We combine 131 new medium-resolution (R~2000) J-band spectra of M, L, and T dwarfs from the Keck NIRSPEC Brown Dwarf Spectroscopic Survey (BDSS) with 97 previously published BDSS spectra to study surface-gravity-sensitive indices for 228 low-mass stars and brown dwarfs spanning spectral types M5-T9. Specifically, we use an established set of spectral indices to determine surface gravity classifications for all M6-L7 objects in our sample by measuring equivalent widths (EW) of the K I lines at 1.1692, 1.1778, 1.2529 um, and the 1.2 um FeHJ absorption index. Our results are consistent with previous surface gravity measurements, showing a distinct double peak - at ~L5 and T5 - in K I EW as a function of spectral type. We analyze K I EWs of 73 objects of known ages and find a linear trend between log(Age) and EW. From this relationship, we assign age ranges to the very low gravity, intermediate gravity, and field gravity designations for spectral types M6-L0. Interestingly, the ages probed by these designations remain broad, change with spectral type, and depend on the gravity sensitive index used. Gravity designations are useful indicators of the possibility of youth, but current datasets cannot be used to provide a precise age estimate.Comment: 33 pages, 13 figures, ApJ in pres