Evaluation of Skylab photography for water resources, San Luis Valley, Colorado

NASA Technical Reports Server (NTRS)

Lee, K. (Principal Investigator); Huntley, D.

1975-01-01

The author has identified the following significant results. Skylab S190A photography used in a stereo mode is sufficient for defining the drainage divides and drainage patterns at the regional level. This data, combined with geologic information, define the boundaries and distribution of ground water recharge and discharge areas within the basin.

Large-area fabrication of patterned ZnO-nanowire arrays using light stamping lithography.

PubMed

Hwang, Jae K; Cho, Sangho; Seo, Eun K; Myoung, Jae M; Sung, Myung M

2009-12-01

We demonstrate selective adsorption and alignment of ZnO nanowires on patterned poly(dimethylsiloxane) (PDMS) thin layers with (aminopropyl)siloxane self-assembled monolayers (SAMs). Light stamping lithography (LSL) was used to prepare patterned PDMS thin layers as neutral passivation regions on Si substrates. (3-Aminopropyl)triethoxysilane-based SAMs were selectively formed only on regions exposing the silanol groups of the Si substrates. The patterned positively charged amino groups define and direct the selective adsorption of ZnO nanowires with negative surface charges in the protic solvent. This procedure can be adopted in automated printing machines that generate patterned ZnO-nanowire arrays on large-area substrates. To demonstrate its usefulness, the LSL method was applied to prepare ZnO-nanowire transistor arrays on 4-in. Si wafers.

Photo-Definable Self Assembled Maerials

DOEpatents

DOSHI, DHAVAL; [et al

2004-10-26

The present invention provides a mesoporous material comprising at least one region of mesoporous material patterned at a lithographic scale. The present invention also provides a a method for forming a patterned mesoporous material comprising: coating a sol on a substrate to form a film, the sol comprising: a templating molecule, a photoactivator generator, a material capable of being sol-gel processed, water, and a solvent; and exposing the film to light to form a patterned mesoporous material.

Fine-scale variation in meiotic recombination in Mimulus inferred from population shotgun sequencing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hellsten, Uffe; Wright, Kevin M.; Jenkins, Jerry

2013-11-13

Meiotic recombination rates can vary widely across genomes, with hotspots of intense activity interspersed among cold regions. In yeast, hotspots tend to occur in promoter regions of genes, whereas in humans and mice hotspots are largely defined by binding sites of the PRDM9 protein. To investigate the detailed recombination pattern in a flowering plant we use shotgun resequencing of a wild population of the monkeyflower Mimulus guttatus to precisely locate over 400,000 boundaries of historic crossovers or gene conversion tracts. Their distribution defines some 13,000 hotspots of varying strengths, interspersed with cold regions of undetectably low recombination. Average recombination ratesmore » peak near starts of genes and fall off sharply, exhibiting polarity. Within genes, recombination tracts are more likely to terminate in exons than in introns. The general pattern is similar to that observed in yeast, as well as in PRDM9-knockout mice, suggesting that recombination initiation described here in Mimulus may reflect ancient and conserved eukaryotic mechanisms« less

A Facile Route for Patterned Growth of Metal-Insulator Carbon Lateral Junction through One-Pot Synthesis.

PubMed

Park, Beomjin; Park, Jaesung; Son, Jin Gyeong; Kim, Yong-Jin; Yu, Seong Uk; Park, Hyo Ju; Chae, Dong-Hun; Byun, Jinseok; Jeon, Gumhye; Huh, Sung; Lee, Seoung-Ki; Mishchenko, Artem; Hyun, Seung; Lee, Tae Geol; Han, Sang Woo; Ahn, Jong-Hyun; Lee, Zonghoon; Hwang, Chanyong; Novoselov, Konstantin S; Kim, Kwang S; Hong, Byung Hee; Kim, Jin Kon

2015-08-25

Precise graphene patterning is of critical importance for tailor-made and sophisticated two-dimensional nanoelectronic and optical devices. However, graphene-based heterostructures have been grown by delicate multistep chemical vapor deposition methods, limiting preparation of versatile heterostructures. Here, we report one-pot synthesis of graphene/amorphous carbon (a-C) heterostructures from a solid source of polystyrene via selective photo-cross-linking process. Graphene is successfully grown from neat polystyrene regions, while patterned cross-linked polystyrene regions turn into a-C because of a large difference in their thermal stability. Since the electrical resistance of a-C is at least 2 orders of magnitude higher than that for graphene, the charge transport in graphene/a-C heterostructure occurs through the graphene region. Measurement of the quantum Hall effect in graphene/a-C lateral heterostructures clearly confirms the reliable quality of graphene and well-defined graphene/a-C interface. The direct synthesis of patterned graphene from polymer pattern could be further exploited to prepare versatile heterostructures.

Clustering Of Left Ventricular Wall Motion Patterns

NASA Astrophysics Data System (ADS)

Bjelogrlic, Z.; Jakopin, J.; Gyergyek, L.

1982-11-01

A method for detection of wall regions with similar motion was presented. A model based on local direction information was used to measure the left ventricular wall motion from cineangiographic sequence. Three time functions were used to define segmental motion patterns: distance of a ventricular contour segment from the mean contour, the velocity of a segment and its acceleration. Motion patterns were clustered by the UPGMA algorithm and by an algorithm based on K-nearest neighboor classification rule.

Perceived spatial displacement of motion-defined contours in peripheral vision.

PubMed

Fan, Zhao; Harris, John

2008-12-01

The perceived displacement of motion-defined contours in peripheral vision was examined in four experiments. In Experiment 1, in line with Ramachandran and Anstis' finding [Ramachandran, V. S., & Anstis, S. M. (1990). Illusory displacement of equiluminous kinetic edges. Perception, 19, 611-616], the border between a field of drifting dots and a static dot pattern was apparently displaced in the same direction as the movement of the dots. When a uniform dark area was substituted for the static dots, a similar displacement was found, but this was smaller and statistically insignificant. In Experiment 2, the border between two fields of dots moving in opposite directions was displaced in the direction of motion of the dots in the more eccentric field, so that the location of a boundary defined by a diverging pattern is perceived as more eccentric, and that defined by a converging as less eccentric. Two explanations for this effect (that the displacement reflects a greater weight given to the more eccentric motion, or that the region containing stronger centripetal motion components expands perceptually into that containing centrifugal motion) were tested in Experiment 3, by varying the velocity of the more eccentric region. The results favoured the explanation based on the expansion of an area in centripetal motion. Experiment 4 showed that the difference in perceived location was unlikely to be due to differences in the discriminability of contours in diverging and converging patterns, and confirmed that this effect is due to a difference between centripetal and centrifugal motion rather than motion components in other directions. Our result provides new evidence for a bias towards centripetal motion in human vision, and suggests that the direction of motion-induced displacement of edges is not always in the direction of an adjacent moving pattern.

Using Dragon Curves To Learn about Length and Area.

ERIC Educational Resources Information Center

Smith, Lyle R.

1999-01-01

Utilizes dragon curves which are made with three tiles and can be used to create fascinating patterns to help students understand the concepts of length, area, and perimeter of regions as defined by dragon curves. (ASK)

Satellite classification and segmentation using non-additive entropy

NASA Astrophysics Data System (ADS)

Assirati, Lucas; Souto Martinez, Alexandre; Martinez Bruno, Odemir

2014-03-01

Here we compare the Boltzmann-Gibbs-Shannon (standard) with the Tsallis entropy on the pattern recognition and segmentation of colored images obtained by satellites, via "Google Earth". By segmentation we mean particionate an image to locate regions of interest. Here, we discriminate and define an image partition classes according to a training basis. This training basis consists of three pattern classes: aquatic, urban and vegetation regions. Our numerical experiments demonstrate that the Tsallis entropy, used as a feature vector composed of distinct entropic indexes q outperforms the standard entropy. There are several applications of our proposed methodology, once satellite images can be used to monitor migration form rural to urban regions, agricultural activities, oil spreading on the ocean etc.

A Holding Function for Conflict Probe Appiications

NASA Technical Reports Server (NTRS)

McNally, Dave; Walton, Joe

2004-01-01

Conflict Alerts for aircraft in holding patterns are often missed or in error due to fact that holding trajectories are not modeled in Conflict Alert or Conflict Probe logic. In addition, a controller in one sector may not know when aircraft are holding in a neighboring sector. These factors can lead to an increased potential for loss of separation while aircraft are flying in holding patterns. A holding function for conflict probe applications has been developed and tested with air traffic data from Fort Worth Center. The holding function automatically determines when an aircraft enters a holding pattern, builds a holding region around the pattern and then probes the region for conflict with other traffic. The operational concept of use assumes that air traffic controllers are very busy during periods when aircraft are in holding and therefore don't have time to manually enter information which defines a holding pattern and activates conflict probing. For this reason, it is important the holding function automatically detect aircraft in holding and compute a holding region for conflict analysis. The controller is then alerted if other aircraft are predicted to fly through the holding region at the holding altitude.

Method of construction of a multi-cell solar array

NASA Technical Reports Server (NTRS)

Routh, D. E.; Hollis, B. R., Jr.; Feltner, W. R. (Inventor)

1979-01-01

The method of constructing a high voltage, low power, multicell solar array is described. A solar cell base region is formed in a substrate such as but not limited to silicon or sapphire. A protective coating is applied on the base and a patterned etching of the coating and base forms discrete base regions. A semiconductive junction and upper active region are formed in each base region, and defined by photolithography. Thus, discrete cells which are interconnected by metallic electrodes are formed.

R1/R4 (Northern/Intermountain Regions) fish and fish habitat standard inventory procedures handbook

Treesearch

C. Kerry Overton; Sherry P. Wollrab; Bruce C. Roberts; Michael A. Radko

1997-01-01

This handbook describes the standard inventory procedures for collecting fish habitat and salmonid fish species data for streams managed by the Northern (R1) and Intermountain (R4) Regions of the Forest Service, U.S. Department of Agriculture. The inventory procedures are designed to define and quantify the structure, pattern, and dimensions of fish habitat; describe...

Migration of tree species in New England based on elevational and regional analyses

Treesearch

Dale S. Solomon; William B. Leak

1994-01-01

With field measurements of migration patterns, we used two complementary approaches to examine tree-species movement after a documented increase in temperatures. The advancing-front theory was used to examine age trends over distance and elevation for both a mountain site in New Hampshire and a regional comparison across the State of Maine. Well-defined stationary...

A new precipitation and meteorological drought climatology based on weather patterns

NASA Astrophysics Data System (ADS)

Richardson, D.; Fowler, H. J.; Kilsby, C. G.; Neal, R.

2017-12-01

Weather-pattern, or weather-type, classifications are a valuable tool in many applications as they characterise the broad-scale atmospheric circulation over a given region. An analysis of regional UK precipitation and meteorological drought climatology with respect to a set of objectively defined weather patterns is presented. This classification system, introduced last year, is currently being used by the Met Office in several probabilistic forecasting applications driven by ensemble forecasting systems. The classification consists of 30 daily patterns derived from North Atlantic Ocean and European mean sea level pressure data. Clustering these 30 patterns yields another set of eight patterns that are intended for use in longer-range applications. Weather pattern definitions and daily occurrences are mapped to the commonly-used Lamb Weather Types (LWTs), and parallels between the two classifications are drawn. Daily precipitation distributions are associated with each weather pattern and LWT. Drought index series are calculated for a range of aggregation periods and seasons. Monthly weather-pattern frequency anomalies are calculated for different drought index thresholds, representing dry, wet and drought conditions. The set of 30 weather patterns is shown to be adequate for precipitation-based analyses in the UK, although the smaller set of clustered patterns is not. Furthermore, intra-pattern precipitation variability is lower in the new classification compared to the LWTs, which is an advantage in the context of precipitation studies. Weather patterns associated with drought over the different UK regions are identified. This has potential forecasting application - if a model (e.g. a global seasonal forecast model) can predict weather pattern occurrences then regional drought outlooks may be derived from the forecasted weather patterns.

Gaussian pre-filtering for uncertainty minimization in digital image correlation using numerically-designed speckle patterns

NASA Astrophysics Data System (ADS)

Mazzoleni, Paolo; Matta, Fabio; Zappa, Emanuele; Sutton, Michael A.; Cigada, Alfredo

2015-03-01

This paper discusses the effect of pre-processing image blurring on the uncertainty of two-dimensional digital image correlation (DIC) measurements for the specific case of numerically-designed speckle patterns having particles with well-defined and consistent shape, size and spacing. Such patterns are more suitable for large measurement surfaces on large-scale specimens than traditional spray-painted random patterns without well-defined particles. The methodology consists of numerical simulations where Gaussian digital filters with varying standard deviation are applied to a reference speckle pattern. To simplify the pattern application process for large areas and increase contrast to reduce measurement uncertainty, the speckle shape, mean size and on-center spacing were selected to be representative of numerically-designed patterns that can be applied on large surfaces through different techniques (e.g., spray-painting through stencils). Such 'designer patterns' are characterized by well-defined regions of non-zero frequency content and non-zero peaks, and are fundamentally different from typical spray-painted patterns whose frequency content exhibits near-zero peaks. The effect of blurring filters is examined for constant, linear, quadratic and cubic displacement fields. Maximum strains between ±250 and ±20,000 με are simulated, thus covering a relevant range for structural materials subjected to service and ultimate stresses. The robustness of the simulation procedure is verified experimentally using a physical speckle pattern subjected to constant displacements. The stability of the relation between standard deviation of the Gaussian filter and measurement uncertainty is assessed for linear displacement fields at varying image noise levels, subset size, and frequency content of the speckle pattern. It is shown that bias error as well as measurement uncertainty are minimized through Gaussian pre-filtering. This finding does not apply to typical spray-painted patterns without well-defined particles, for which image blurring is only beneficial in reducing bias errors.

Towards machine ecoregionalization of Earth's landmass using pattern segmentation method

NASA Astrophysics Data System (ADS)

Nowosad, Jakub; Stepinski, Tomasz F.

2018-07-01

We present and evaluate a quantitative method for delineation of ecophysiographic regions throughout the entire terrestrial landmass. The method uses the new pattern-based segmentation technique which attempts to emulate the qualitative, weight-of-evidence approach to a delineation of ecoregions in a computer code. An ecophysiographic region is characterized by homogeneous physiography defined by the cohesiveness of patterns of four variables: land cover, soils, landforms, and climatic patterns. Homogeneous physiography is a necessary but not sufficient condition for a region to be an ecoregion, thus machine delineation of ecophysiographic regions is the first, important step toward global ecoregionalization. In this paper, we focus on the first-order approximation of the proposed method - delineation on the basis of the patterns of the land cover alone. We justify this approximation by the existence of significant spatial associations between various physiographic variables. Resulting ecophysiographic regionalization (ECOR) is shown to be more physiographically homogeneous than existing global ecoregionalizations (Terrestrial Ecoregions of the World (TEW) and Bailey's Ecoregions of the Continents (BEC)). The presented quantitative method has an advantage of being transparent and objective. It can be verified, easily updated, modified and customized for specific applications. Each region in ECOR contains detailed, SQL-searchable information about physiographic patterns within it. It also has a computer-generated label. To give a sense of how ECOR compares to TEW and, in the U.S., to EPA Level III ecoregions, we contrast these different delineations using two specific sites as examples. We conclude that ECOR yields regionalization somewhat similar to EPA level III ecoregions, but for the entire world, and by automatic means.

CLUSTER ANALYSIS OF GREAT BASIN ECOREGIONS USING R-EMAP STREAM DATA

EPA Science Inventory

Ecological regions ( ecoregions ) are defined as areas of relative homogeneity in ecosystem type, quality and quantity of environmental resources. Ecoregions are identified by analyzing biotic and abiotic geographic patterns, which are natural and human related. Parameters used i...

Self-assembly and hierarchical patterning of aligned organic nanowire arrays by solvent evaporation on substrates with patterned wettability.

PubMed

Bao, Rong-Rong; Zhang, Cheng-Yi; Zhang, Xiu-Juan; Ou, Xue-Mei; Lee, Chun-Sing; Jie, Jian-Sheng; Zhang, Xiao-Hong

2013-06-26

The controlled growth and alignment of one-dimensional organic nanostructures at well-defined locations considerably hinders the integration of nanostructures for electronic and optoelectronic applications. Here, we demonstrate a simple process to achieve the growth, alignment, and hierarchical patterning of organic nanowires on substrates with controlled patterns of surface wettability. The first-level pattern is confined by the substrate patterns of wettability. Organic nanostructures are preferentially grown on solvent wettable regions. The second-level pattern is the patterning of aligned organic nanowires deposited by controlling the shape and movement of the solution contact lines during evaporation on the wettable regions. This process is controlled by the cover-hat-controlled method or vertical evaportation method. Therefore, various new patterns of organic nanostructures can be obtained by combing these two levels of patterns. This simple method proves to be a general approach that can be applied to other organic nanostructure systems. Using the as-prepared patterned nanowire arrays, an optoelectronic device (photodetector) is easily fabricated. Hence, the proposed simple, large-scale, low-cost method of preparing patterns of highly ordered organic nanostructures has high potential applications in various electronic and optoelectronic devices.

A Teleconnection between the West Siberian Plain and the ENSO Region

NASA Astrophysics Data System (ADS)

Liess, S.; Agrawal, S.; Chatterjee, S.; Kumar, V.

2017-12-01

This study presents a mechanism that links the El Niño/Southern Oscillation (ENSO) to extratropical waves that are deflected from the Northern Hemisphere polar regions and travel southeastward over Central Asia toward the west Pacific warm pool during northern winter. The initial wave pattern resembles the well-known East Atlantic-West Russia pattern. Here we show its influence on the ENSO region. We identify a tripole pattern between the West Siberian Plain and the two centers of action of ENSO with a graph-based approach. It indicates that the background state of ENSO with respect to global sea level pressure (SLP) has a significant negative correlation to the West Siberian Plain. The correlation with the background state, which is defined by the sum of the two centers of action of ENSO, is higher than each of the pairwise correlations with either of the ENSO centers alone. We define the centers with a clustering algorithm that detects regions with similar characteristics. The normalized monthly SLP time series for the two centers of ENSO (around Darwin, Australia and Tahiti) are area-averaged and the sum of both regions is considered as the background state of ENSO. This wave train can be detected throughout the troposphere and the lower stratosphere. Its origins can be traced back to atmospheric wave activity triggered by convection over the subtropical North Atlantic that emanates wave activity toward the West Siberian Plain. The same wave train also propagates to the central Pacific Ocean around Tahiti and can be used to predict the background state over the ENSO region. This background state also modifies the subtropical bridge between the tropical east Pacific and the subtropical North Atlantic, thus leading to a circumglobal wave train.

Complex-ordered patterns in shaken convection.

PubMed

Rogers, Jeffrey L; Pesch, Werner; Brausch, Oliver; Schatz, Michael F

2005-06-01

We report and analyze complex patterns observed in a combination of two standard pattern forming experiments. These exotic states are composed of two distinct spatial scales, each displaying a different temporal dependence. The system is a fluid layer experiencing forcing from both a vertical temperature difference and vertical time-periodic oscillations. Depending on the parameters these forcing mechanisms produce fluid motion with either a harmonic or a subharmonic temporal response. Over a parameter range where these mechanisms have comparable influence the spatial scales associated with both responses are found to coexist, resulting in complex, yet highly ordered patterns. Phase diagrams of this region are reported and criteria to define the patterns as quasiperiodic crystals or superlattices are presented. These complex patterns are found to satisfy four-mode (resonant tetrad) conditions. The qualitative difference between the present formation mechanism and the resonant triads ubiquitously used to explain complex-ordered patterns in other nonequilibrium systems is discussed. The only exception to quantitative agreement between our analysis based on Boussinesq equations and laboratory investigations is found to be the result of breaking spatial symmetry in a small parameter region near onset.

Isolation and measurement of the features of arrays of cell aggregates formed by dielectrophoresis using the user-specified Multi Regions Masking (MRM) technique

NASA Astrophysics Data System (ADS)

Yusvana, Rama; Headon, Denis; Markx, Gerard H.

2009-08-01

The use of dielectrophoresis for the construction of artificial skin tissue with skin cells in follicle-like 3D cell aggregates in well-defined patterns is demonstrated. To analyse the patterns produced and to study their development after their formation a Virtual Instrument (VI) system was developed using the LabVIEW IMAQ Vision Development Module. A series of programming functions (algorithms) was used to isolate the features on the image (in our case; the patterned aggregates) and separate them from all other unwanted regions on the image. The image was subsequently converted into a binary version, covering only the desired microarray regions which could then be analysed by computer for automatic object measurements. The analysis utilized the simple and easy-to-use User-Specified Multi-Regions Masking (MRM) technique, which allows one to concentrate the analysis on the desired regions specified in the mask. This simplified the algorithms for the analysis of images of cell arrays having similar geometrical properties. By having a collection of scripts containing masks of different patterns, it was possible to quickly and efficiently develop sets of custom virtual instruments for the offline or online analysis of images of cell arrays in the database.

Defining Scenarios: Linking Integrated Models, Regional Concerns, and Stakeholders

NASA Astrophysics Data System (ADS)

Hartmann, H. C.; Stewart, S.; Liu, Y.; Mahmoud, M.

2007-05-01

Scenarios are important tools for long-term planning, and there is great interest in using integrated models in scenario studies. However, scenario definition and assessment are creative, as well as scientific, efforts. Using facilitated creative processes, we have worked with stakeholders to define regionally significant scenarios that encompass a broad range of hydroclimatic, socioeconomic, and institutional dimensions. The regional scenarios subsequently inform the definition of local scenarios that work with context-specific integrated models that, individually, can address only a subset of overall regional complexity. Based on concerns of stakeholders in the semi-arid US Southwest, we prioritized three dimensions that are especially important, yet highly uncertain, for long-term planning: hydroclimatic conditions (increased variability, persistent drought), development patterns (urban consolidation, distributed rural development), and the nature of public institutions (stressed, proactive). Linking across real-world decision contexts and integrated modeling efforts poses challenges of creatively connecting the conceptual models held by both the research and stakeholder communities.

Water color and circulation southern Chesapeake Bay, part 1

NASA Technical Reports Server (NTRS)

Nichols, M. M.; Gordon, H. H.

1975-01-01

Satellite imagery from two EREP passes over the Rappahannock Estuary of the Chesapeake region is analyzed to chart colored water types, to delineate color boundaries and define circulatory patterns. Surface observations from boats and helicopters concurrent with Skylab overpass define the distributions of suspended sediment, transparency, temperature, salinity, phytoplankton, color of suspended material and optical ratio. Important features recorded by the imagery are a large-scale turbidity maximum and massive red tide blooms. Water movement is revealed by small-scale mixing patterns and tidal plumes of apparent sediment-laden water. The color patterns broadly reflect the bottom topography and the seaward gradient of suspended material between the river and the bay. Analyses of red, green and natural color photos by microdensitometry demonstrate the utility of charting water color types of potential use for managing estuarine water quality. The Skylab imagery is superior to aerial photography and surface observations for charting water color.

Defining multiple, distinct, and shared spatiotemporal patterns of DNA replication and endoreduplication from 3D image analysis of developing maize (Zea mays L.) root tip nuclei.

PubMed

Bass, Hank W; Hoffman, Gregg G; Lee, Tae-Jin; Wear, Emily E; Joseph, Stacey R; Allen, George C; Hanley-Bowdoin, Linda; Thompson, William F

2015-11-01

Spatiotemporal patterns of DNA replication have been described for yeast and many types of cultured animal cells, frequently after cell cycle arrest to aid in synchronization. However, patterns of DNA replication in nuclei from plants or naturally developing organs remain largely uncharacterized. Here we report findings from 3D quantitative analysis of DNA replication and endoreduplication in nuclei from pulse-labeled developing maize root tips. In both early and middle S phase nuclei, flow-sorted on the basis of DNA content, replicative labeling was widely distributed across euchromatic regions of the nucleoplasm. We did not observe the perinuclear or perinucleolar replicative labeling patterns characteristic of middle S phase in mammals. Instead, the early versus middle S phase patterns in maize could be distinguished cytologically by correlating two quantitative, continuous variables, replicative labeling and DAPI staining. Early S nuclei exhibited widely distributed euchromatic labeling preferentially localized to regions with weak DAPI signals. Middle S nuclei also exhibited widely distributed euchromatic labeling, but the label was preferentially localized to regions with strong DAPI signals. Highly condensed heterochromatin, including knobs, replicated during late S phase as previously reported. Similar spatiotemporal replication patterns were observed for both mitotic and endocycling maize nuclei. These results revealed that maize euchromatin exists as an intermingled mixture of two components distinguished by their condensation state and replication timing. These different patterns might reflect a previously described genome organization pattern, with "gene islands" mostly replicating during early S phase followed by most of the intergenic repetitive regions replicating during middle S phase.

Some fundamental concepts in remote sensing

NASA Technical Reports Server (NTRS)

1982-01-01

The term remote sensing is defined as well as ideas such as class, pattern, feature, pattern recognition, feature extraction, and theme. The electromagnetic spectrum is examined especially those wavelength regions available to remote sensing. Relevant energy and wave propagation laws are discussed and the characteristics of emitted and reflected radiation and their detection are investigated. The identification of classes by their spectral signatures, the multispectral approach, and the principal types of sensors and platforms used in remote sensing are also considered.

Epidemic Distribution and Variation of Plasmodium falciparum and Plasmodium vivax Malaria in Hainan, China during 1995–2008

PubMed Central

Xiao, Dan; Long, Yong; Wang, Shanqing; Wu, Kejian; Xu, Dezhong; Li, Haitao; Wang, Guangze; Yan, Yongping

2012-01-01

Hainan Province is the main area threatened by malaria in China. However, the epidemiologic patterns of malaria in this region are not yet defined. In this study, we determined the spatio-temporal distribution and variation of Plasmodium falciparum and Plasmodium vivax malaria in Hainan during 1995–2008 by using wavelet and cluster quantitative approaches. The results indicated a decreasing secular trend and obvious seasonal fluctuation of malaria in Hainan. In addition, the characteristic annual peak of malaria could not be detected after 2005. The southcentral region of Hainan has remained an area of relatively high malaria risk, but the incidence of P. falciparum malaria increased significantly in the southeast and southwest regions during 2002–2008. These findings identify epidemic patterns of malaria in Hainan, and are applicable for designing an effective and dynamic public health campaign to combat malaria in this region. PMID:22869636

Patterns of fMRI activity dissociate overlapping functional brain areas that respond to biological motion.

PubMed

Peelen, Marius V; Wiggett, Alison J; Downing, Paul E

2006-03-16

Accurate perception of the actions and intentions of other people is essential for successful interactions in a social environment. Several cortical areas that support this process respond selectively in fMRI to static and dynamic displays of human bodies and faces. Here we apply pattern-analysis techniques to arrive at a new understanding of the neural response to biological motion. Functionally defined body-, face-, and motion-selective visual areas all responded significantly to "point-light" human motion. Strikingly, however, only body selectivity was correlated, on a voxel-by-voxel basis, with biological motion selectivity. We conclude that (1) biological motion, through the process of structure-from-motion, engages areas involved in the analysis of the static human form; (2) body-selective regions in posterior fusiform gyrus and posterior inferior temporal sulcus overlap with, but are distinct from, face- and motion-selective regions; (3) the interpretation of region-of-interest findings may be substantially altered when multiple patterns of selectivity are considered.

Major determinants of the biogeographic pattern of the shallow-sea fauna

NASA Technical Reports Server (NTRS)

Valentine, J. W.; Jablonski, D.

1982-01-01

The benthic shallow-sea is defined as the region of sea floor lying between the supralittoral zone at the shoreline and the impingement of the thermocline separating a warm shallow and variable portion of the water column from rather homogeneous and constant cooler waters beneath. Three types of shallow-sea provinces can be recognized: (1) one-dimensional, linear shelves; (2) two-dimensional shelves; and (3) scattered islands in two-dimensional arrays. Dispersal powers of marine invertebrates vary with developmental mode, and patterns of dispersal, endemism and speciation vary among the different provincial types. Invertebrate developmental modes vary systematically with geography, and presumably are adaptive to environmental conditions. Clades with only a single mode of development tend to be restricted to regions appropriate to that mode, significantly affecting their biogeographic patterns. The consequences of geographic and other environmental changes are reviewed.

Global diversity and distribution of macrofungi

Treesearch

Gregory M. Mueller; John P. Schmit; Patrick R. Leacock; Bart Buyck; Joaquin Cifuentes; Dennis E. Desjardin; Roy E. Halling; Kurt Hjortstam; Teresa Iturriaga; Karl-Henrik Larsson; D. Jean Lodge; Tom W. May; David Minter; Mario Rajchenberg; Scott A. Redhead; Leif Ryvarden; James M. Trappe; Roy Watling; Qiuxin Wu

2007-01-01

Data on macrofungal diversity and distribution patterns were compiled for major geographical regions of the world. Macrofungi are defined here to include ascomycetes and basidiomycetes with large, easily observed spore-bearing structures that form above or below ground. Each coauthor either provided data on a particular taxonomic group of macrofungi or information on...

Kangaroo – A pattern-matching program for biological sequences

PubMed Central

2002-01-01

Background Biologists are often interested in performing a simple database search to identify proteins or genes that contain a well-defined sequence pattern. Many databases do not provide straightforward or readily available query tools to perform simple searches, such as identifying transcription binding sites, protein motifs, or repetitive DNA sequences. However, in many cases simple pattern-matching searches can reveal a wealth of information. We present in this paper a regular expression pattern-matching tool that was used to identify short repetitive DNA sequences in human coding regions for the purpose of identifying potential mutation sites in mismatch repair deficient cells. Results Kangaroo is a web-based regular expression pattern-matching program that can search for patterns in DNA, protein, or coding region sequences in ten different organisms. The program is implemented to facilitate a wide range of queries with no restriction on the length or complexity of the query expression. The program is accessible on the web at http://bioinfo.mshri.on.ca/kangaroo/ and the source code is freely distributed at http://sourceforge.net/projects/slritools/. Conclusion A low-level simple pattern-matching application can prove to be a useful tool in many research settings. For example, Kangaroo was used to identify potential genetic targets in a human colorectal cancer variant that is characterized by a high frequency of mutations in coding regions containing mononucleotide repeats. PMID:12150718

Scaling Linguistic Characterization of Precipitation Variability

NASA Astrophysics Data System (ADS)

Primo, C.; Gutierrez, J. M.

2003-04-01

Rainfall variability is influenced by changes in the aggregation of daily rainfall. This problem is of great importance for hydrological, agricultural and ecological applications. Rainfall averages, or accumulations, are widely used as standard climatic parameters. However different aggregation schemes may lead to the same average or accumulated values. In this paper we present a fractal method to characterize different aggregation schemes. The method provides scaling exponents characterizing weekly or monthly rainfall patterns for a given station. To this aim, we establish an analogy with linguistic analysis, considering precipitation as a discrete variable (e.g., rain, no rain). Each weekly, or monthly, symbolic precipitation sequence of observed precipitation is then considered as a "word" (in this case, a binary word) which defines a specific weekly rainfall pattern. Thus, each site defines a "language" characterized by the words observed in that site during a period representative of the climatology. Then, the more variable the observed weekly precipitation sequences, the more complex the obtained language. To characterize these languages, we first applied the Zipf's method obtaining scaling histograms of rank ordered frequencies. However, to obtain significant exponents, the scaling must be maintained some orders of magnitude, requiring long sequences of daily precipitation which are not available at particular stations. Thus this analysis is not suitable for applications involving particular stations (such as regionalization). Then, we introduce an alternative fractal method applicable to data from local stations. The so-called Chaos-Game method uses Iterated Function Systems (IFS) for graphically representing rainfall languages, in a way that complex languages define complex graphical patterns. The box-counting dimension and the entropy of the resulting patterns are used as linguistic parameters to quantitatively characterize the complexity of the patterns. We illustrate the high climatological discrimination power of the linguistic parameters in the Iberian peninsula, when compared with other standard techniques (such as seasonal mean accumulated precipitation). As an example, standard and linguistic parameters are used as inputs for a clustering regionalization method, comparing the resulting clusters.

A new precipitation and drought climatology based on weather patterns.

PubMed

Richardson, Douglas; Fowler, Hayley J; Kilsby, Christopher G; Neal, Robert

2018-02-01

Weather-pattern, or weather-type, classifications are a valuable tool in many applications as they characterize the broad-scale atmospheric circulation over a given region. This study analyses the aspects of regional UK precipitation and meteorological drought climatology with respect to a new set of objectively defined weather patterns. These new patterns are currently being used by the Met Office in several probabilistic forecasting applications driven by ensemble forecasting systems. Weather pattern definitions and daily occurrences are mapped to Lamb weather types (LWTs), and parallels between the two classifications are drawn. Daily precipitation distributions are associated with each weather pattern and LWT. Standardized precipitation index (SPI) and drought severity index (DSI) series are calculated for a range of aggregation periods and seasons. Monthly weather-pattern frequency anomalies are calculated for SPI wet and dry periods and for the 5% most intense DSI-based drought months. The new weather-pattern definitions and daily occurrences largely agree with their respective LWTs, allowing comparison between the two classifications. There is also broad agreement between weather pattern and LWT changes in frequencies. The new data set is shown to be adequate for precipitation-based analyses in the UK, although a smaller set of clustered weather patterns is not. Furthermore, intra-pattern precipitation variability is lower in the new classification compared to the LWTs, which is an advantage in this context. Six of the new weather patterns are associated with drought over the entire UK, with several other patterns linked to regional drought. It is demonstrated that the new data set of weather patterns offers a new opportunity for classification-based analyses in the UK.

A new precipitation and drought climatology based on weather patterns

PubMed Central

Fowler, Hayley J.; Kilsby, Christopher G.; Neal, Robert

2017-01-01

ABSTRACT Weather‐pattern, or weather‐type, classifications are a valuable tool in many applications as they characterize the broad‐scale atmospheric circulation over a given region. This study analyses the aspects of regional UK precipitation and meteorological drought climatology with respect to a new set of objectively defined weather patterns. These new patterns are currently being used by the Met Office in several probabilistic forecasting applications driven by ensemble forecasting systems. Weather pattern definitions and daily occurrences are mapped to Lamb weather types (LWTs), and parallels between the two classifications are drawn. Daily precipitation distributions are associated with each weather pattern and LWT. Standardized precipitation index (SPI) and drought severity index (DSI) series are calculated for a range of aggregation periods and seasons. Monthly weather‐pattern frequency anomalies are calculated for SPI wet and dry periods and for the 5% most intense DSI‐based drought months. The new weather‐pattern definitions and daily occurrences largely agree with their respective LWTs, allowing comparison between the two classifications. There is also broad agreement between weather pattern and LWT changes in frequencies. The new data set is shown to be adequate for precipitation‐based analyses in the UK, although a smaller set of clustered weather patterns is not. Furthermore, intra‐pattern precipitation variability is lower in the new classification compared to the LWTs, which is an advantage in this context. Six of the new weather patterns are associated with drought over the entire UK, with several other patterns linked to regional drought. It is demonstrated that the new data set of weather patterns offers a new opportunity for classification‐based analyses in the UK. PMID:29456290

Innervation pattern of the suprascapular nerve within supraspinatus: a three-dimensional computer modeling study.

PubMed

Hermenegildo, J A; Roberts, S L; Kim, S Y

2014-05-01

The relationship between the innervation pattern of the suprascapular nerve (SSN) and the muscle architecture of supraspinatus has not been thoroughly investigated. The supraspinatus is composed of two architecturally distinct regions: anterior and posterior. Each of these regions is further subdivided into three parts: superficial, middle and deep. The purpose of this study was to investigate the course of the SSN throughout the volume of supraspinatus and to relate the intramuscular branches to the distinct regions and parts of the supraspinatus. The SSN was dissected in thirty formalin embalmed cadaveric specimens and digitized throughout the muscle volume in six of those specimens. The digitized data were modeled using Autodesk(®) Maya(®) 2011. The three-dimensional (3D) models were used to relate the intramuscular innervation pattern to the muscle and tendon architecture defined by Kim et al. (2007, Clin Anat 20:648-655). The SSN bifurcated into two main trunks: medial and lateral. All parts of the anterior region were predominantly innervated by the medial trunk and its proximal and medial branches, whereas all parts of the posterior region predominantly by the lateral trunk and its posterolateral and/or posteromedial branches. The posterior region also received innervation from the proximal branch of the medial trunk in half of the specimens. These findings provide evidence that the anterior and posterior regions are distinct with respect to their innervation. The 3D map of the innervation pattern will aid in planning future clinical studies investigating muscle activation patterns and provide insight into possible injury of the nerve with supraspinatus pathology and surgical techniques. Copyright © 2013 Wiley Periodicals, Inc.

A discrete model of Drosophila eggshell patterning reveals cell-autonomous and juxtacrine effects.

PubMed

Fauré, Adrien; Vreede, Barbara M I; Sucena, Elio; Chaouiya, Claudine

2014-03-01

The Drosophila eggshell constitutes a remarkable system for the study of epithelial patterning, both experimentally and through computational modeling. Dorsal eggshell appendages arise from specific regions in the anterior follicular epithelium that covers the oocyte: two groups of cells expressing broad (roof cells) bordered by rhomboid expressing cells (floor cells). Despite the large number of genes known to participate in defining these domains and the important modeling efforts put into this developmental system, key patterning events still lack a proper mechanistic understanding and/or genetic basis, and the literature appears to conflict on some crucial points. We tackle these issues with an original, discrete framework that considers single-cell models that are integrated to construct epithelial models. We first build a phenomenological model that reproduces wild type follicular epithelial patterns, confirming EGF and BMP signaling input as sufficient to establish the major features of this patterning system within the anterior domain. Importantly, this simple model predicts an instructive juxtacrine signal linking the roof and floor domains. To explore this prediction, we define a mechanistic model that integrates the combined effects of cellular genetic networks, cell communication and network adjustment through developmental events. Moreover, we focus on the anterior competence region, and postulate that early BMP signaling participates with early EGF signaling in its specification. This model accurately simulates wild type pattern formation and is able to reproduce, with unprecedented level of precision and completeness, various published gain-of-function and loss-of-function experiments, including perturbations of the BMP pathway previously seen as conflicting results. The result is a coherent model built upon rules that may be generalized to other epithelia and developmental systems.

A look inside the nerve - Morphology of nerve fascicles in healthy controls and patients with polyneuropathy.

PubMed

Grimm, Alexander; Winter, Natalie; Rattay, Tim W; Härtig, Florian; Dammeier, Nele M; Auffenberg, Eva; Koch, Marilin; Axer, Hubertus

2017-12-01

Polyneuropathies are increasingly analyzed by ultrasound. Summarizing, diffuse enlargement is typical in Charcot-Marie Tooth type 1 (CMT1a), regional enlargement occurs in inflammatory neuropathies. However, a distinction of subtypes is still challenging. Therefore, this study focused on fascicle size and pattern in controls and distinct neuropathies. Cross-sectional area (CSA) of the median, ulnar and peroneal nerve (MN, UN, PN) was measured at predefined landmarks in 50 healthy controls, 15 CMT1a and 13 MMN patients. Additionally, largest fascicle size and number of visible fascicles was obtained at the mid-upper arm cross-section of the MN and UN and in the popliteal fossa cross-section of the PN. Cut-off normal values for fascicle size in the MN, UN and PN were defined (<4.8mm 2 , <2.8mm 2 and <3.5mm 2 ). In CMT1a CSA and fascicle values are significantly enlarged in all nerves, while in MMN CSA and fascicles are regionally enlarged with predominance in the upper arm nerves. The ratio of enlarged fascicles and all fascicles was significantly increased in CMT1a (>50%) in all nerves (p<0.0001), representing diffuse fascicle enlargement, and moderately increased in MMN (>20%), representing differential fascicle enlargement (enlarged and normal fascicles at the same location) sparing the peroneal nerve (regional fascicle enlargement). Based on these findings distinct fascicle patterns were defined. Normal values for fascicle size could be evaluated; while CMT1a features diffuse fascicle enlargement, MMN shows regional and differential predominance with enlarged fascicles as single pathology. Pattern analysis of fascicles might facilitate distinction of several otherwise similar neuropathies. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Characterizing brain patterns in conversion from mild cognitive impairment (MCI) to Alzheimer's disease

NASA Astrophysics Data System (ADS)

Silva R., Santiago S.; Giraldo, Diana L.; Romero, Eduardo

2017-11-01

Structural Magnetic Resonance (MR) brain images should provide quantitative information about the stage and progression of Alzheimer's disease. However, the use of MRI is limited and practically reduced to corroborate a diagnosis already performed with neuropsychological tools. This paper presents an automated strategy for extraction of relevant anatomic patterns related with the conversion from mild cognitive impairment (MCI) to Alzheimer's disease (AD) using T1-weighted MR images. The process starts by representing each of the possible classes with models generated from a linear combination of volumes. The difference between models allows us to establish which are the regions where relevant patterns might be located. The approach searches patterns in a space of brain sulci, herein approximated by the most representative gradients found in regions of interest defined by the difference between the linear models. This hypothesis is assessed by training a conventional SVM model with the found relevant patterns under a leave-one-out scheme. The resultant AUC was 0.86 for the group of women and 0.61 for the group of men.

Transterm—extended search facilities and improved integration with other databases

PubMed Central

Jacobs, Grant H.; Stockwell, Peter A.; Tate, Warren P.; Brown, Chris M.

2006-01-01

Transterm has now been publicly available for >10 years. Major changes have been made since its last description in this database issue in 2002. The current database provides data for key regions of mRNA sequences, a curated database of mRNA motifs and tools to allow users to investigate their own motifs or mRNA sequences. The key mRNA regions database is derived computationally from Genbank. It contains 3′ and 5′ flanking regions, the initiation and termination signal context and coding sequence for annotated CDS features from Genbank and RefSeq. The database is non-redundant, enabling summary files and statistics to be prepared for each species. Advances include providing extended search facilities, the database may now be searched by BLAST in addition to regular expressions (patterns) allowing users to search for motifs such as known miRNA sequences, and the inclusion of RefSeq data. The database contains >40 motifs or structural patterns important for translational control. In this release, patterns from UTRsite and Rfam are also incorporated with cross-referencing. Users may search their sequence data with Transterm or user-defined patterns. The system is accessible at . PMID:16381889

Distributed affective space represents multiple emotion categories across the human brain

PubMed Central

Saarimäki, Heini; Ejtehadian, Lara Farzaneh; Jääskeläinen, Iiro P; Vuilleumier, Patrik; Sams, Mikko; Nummenmaa, Lauri

2018-01-01

Abstract The functional organization of human emotion systems as well as their neuroanatomical basis and segregation in the brain remains unresolved. Here, we used pattern classification and hierarchical clustering to characterize the organization of a wide array of emotion categories in the human brain. We induced 14 emotions (6 ‘basic’, e.g. fear and anger; and 8 ‘non-basic’, e.g. shame and gratitude) and a neutral state using guided mental imagery while participants' brain activity was measured with functional magnetic resonance imaging (fMRI). Twelve out of 14 emotions could be reliably classified from the haemodynamic signals. All emotions engaged a multitude of brain areas, primarily in midline cortices including anterior and posterior cingulate gyri and precuneus, in subcortical regions, and in motor regions including cerebellum and premotor cortex. Similarity of subjective emotional experiences was associated with similarity of the corresponding neural activation patterns. We conclude that different basic and non-basic emotions have distinguishable neural bases characterized by specific, distributed activation patterns in widespread cortical and subcortical circuits. Regionally differentiated engagement of these circuits defines the unique neural activity pattern and the corresponding subjective feeling associated with each emotion. PMID:29618125

PET Imaging of Tau Deposition in the Aging Human Brain

PubMed Central

Schonhaut, Daniel R.; O’Neil, James P.; Janabi, Mustafa; Ossenkoppele, Rik; Baker, Suzanne L.; Vogel, Jacob W.; Faria, Jamie; Schwimmer, Henry D.; Rabinovici, Gil D.; Jagust, William J.

2016-01-01

SUMMARY Tau pathology is a hallmark of Alzheimer’s disease (AD) but also occurs in normal cognitive aging. Using the tau PET agent 18F-AV-1451, we examined retention patterns in cognitively normal older people in relation to young controls and AD patients. Age and β-amyloid (measured using PiB PET) were differentially associated with tau tracer retention in healthy aging. Older age was related to increased tracer retention in regions of the medial temporal lobe, which predicted worse episodic memory performance. PET detection of tau in other isocortical regions required the presence of cortical β-amyloid, and was associated with decline in global cognition. Furthermore, patterns of tracer retention corresponded well with Braak staging of neurofibrillary tau pathology. The present study defined patterns of tau tracer retention in normal aging in relation to age, cognition, and β-amyloid deposition. PMID:26938442

PET Imaging of Tau Deposition in the Aging Human Brain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schöll, Michael; Lockhart, Samuel N.; Schonhaut, Daniel R.

Tau pathology is a hallmark of Alzheimer’s disease (AD) but also occurs in normal cognitive aging. In this study, using the tau PET agent 18F-AV-1451, we examined retention patterns in cognitively normal older people in relation to young controls and AD patients. Age and β-amyloid (measured using PiB PET) were differentially associated with tau tracer retention in healthy aging. Older age was related to increased tracer retention in regions of the medial temporal lobe, which predicted worse episodic memory performance. PET detection of tau in other isocortical regions required the presence of cortical β-amyloid and was associated with decline inmore » global cognition. Furthermore, patterns of tracer retention corresponded well with Braak staging of neurofibrillary tau pathology. In conclusion, the present study defined patterns of tau tracer retention in normal aging in relation to age, cognition, and β-amyloid deposition.« less

PET Imaging of Tau Deposition in the Aging Human Brain

DOE PAGES

Schöll, Michael; Lockhart, Samuel N.; Schonhaut, Daniel R.; ...

2016-03-02

Tau pathology is a hallmark of Alzheimer’s disease (AD) but also occurs in normal cognitive aging. In this study, using the tau PET agent 18F-AV-1451, we examined retention patterns in cognitively normal older people in relation to young controls and AD patients. Age and β-amyloid (measured using PiB PET) were differentially associated with tau tracer retention in healthy aging. Older age was related to increased tracer retention in regions of the medial temporal lobe, which predicted worse episodic memory performance. PET detection of tau in other isocortical regions required the presence of cortical β-amyloid and was associated with decline inmore » global cognition. Furthermore, patterns of tracer retention corresponded well with Braak staging of neurofibrillary tau pathology. In conclusion, the present study defined patterns of tau tracer retention in normal aging in relation to age, cognition, and β-amyloid deposition.« less

Axial mesendoderm refines rostrocaudal pattern in the chick nervous system.

PubMed

Rowan, A M; Stern, C D; Storey, K G

1999-07-01

There has long been controversy concerning the role of the axial mesoderm in the induction and rostrocaudal patterning of the vertebrate nervous system. Here we investigate the neural inducing and regionalising properties of defined rostrocaudal regions of head process/prospective notochord in the chick embryo by juxtaposing these tissues with extraembryonic epiblast or neural plate explants. We localise neural inducing signals to the emerging head process and using a large panel of region-specific neural markers, show that different rostrocaudal levels of the head process derived from headfold stage embryos can induce discrete regions of the central nervous system. However, we also find that rostral and caudal head process do not induce expression of any of these molecular markers in explants of the neural plate. During normal development the head process emerges beneath previously induced neural plate, which we show has already acquired some rostrocaudal character. Our findings therefore indicate that discrete regions of axial mesendoderm at headfold stages are not normally responsible for the establishment of rostrocaudal pattern in the neural plate. Strikingly however, we do find that caudal head process inhibits expression of rostral genes in neural plate explants. These findings indicate that despite the ability to induce specific rostrocaudal regions of the CNS de novo, signals provided by the discrete regions of axial mesendoderm do not appear to establish regional differences, but rather refine the rostrocaudal character of overlying neuroepithelium.

Solar cell collector and method for producing same

NASA Technical Reports Server (NTRS)

Evans, J. C., Jr. (Inventor)

1978-01-01

A transparent, conductive collector layer containing conductive metal channels is formed as a layer on a photovoltaic substrate by coating a photovoltaic substract with a conductive mixed metal layer. A heat sink having portions protruding from one of its surfaces is attached. These protruding portions define a continuous pattern in combination with recessed regions among them such that they are in contact with the conductive layer of the photovoltaic substrate. Heating the substrate while simultaneously oxidizing the portions of the conductive layer exposed to a gaseous oxidizing substance forced into the recessed regions of the heat sink, creates a transparent metal oxide layer on the substrate. A continous pattern of highly conductive metal channels is contained in the metal oxide layer.

Behavioral pattern separation and its link to the neural mechanisms of fear generalization.

PubMed

Lange, Iris; Goossens, Liesbet; Michielse, Stijn; Bakker, Jindra; Lissek, Shmuel; Papalini, Silvia; Verhagen, Simone; Leibold, Nicole; Marcelis, Machteld; Wichers, Marieke; Lieverse, Ritsaert; van Os, Jim; van Amelsvoort, Therese; Schruers, Koen

2017-11-01

Fear generalization is a prominent feature of anxiety disorders and post-traumatic stress disorder (PTSD). It is defined as enhanced fear responding to a stimulus that bears similarities, but is not identical to a threatening stimulus. Pattern separation, a hippocampal-dependent process, is critical for stimulus discrimination; it transforms similar experiences or events into non-overlapping representations. This study is the first in humans to investigate the extent to which fear generalization relies on behavioral pattern separation abilities. Participants (N = 46) completed a behavioral task taxing pattern separation, and a neuroimaging fear conditioning and generalization paradigm. Results show an association between lower behavioral pattern separation performance and increased generalization in shock expectancy scores, but not in fear ratings. Furthermore, lower behavioral pattern separation was associated with diminished recruitment of the subcallosal cortex during presentation of generalization stimuli. This region showed functional connectivity with the orbitofrontal cortex and ventromedial prefrontal cortex. Together, the data provide novel experimental evidence that pattern separation is related to generalization of threat expectancies, and reduced fear inhibition processes in frontal regions. Deficient pattern separation may be critical in overgeneralization and therefore may contribute to the pathophysiology of anxiety disorders and PTSD. © The Author (2017). Published by Oxford University Press.

Opposing Functions of the ETS Factor Family Define Shh Spatial Expression in Limb Buds and Underlie Polydactyly

PubMed Central

Lettice, Laura A.; Williamson, Iain; Wiltshire, John H.; Peluso, Silvia; Devenney, Paul S.; Hill, Alison E.; Essafi, Abdelkader; Hagman, James; Mort, Richard; Grimes, Graeme; DeAngelis, Carlo L.; Hill, Robert E.

2012-01-01

Summary Sonic hedgehog (Shh) expression during limb development is crucial for specifying the identity and number of digits. The spatial pattern of Shh expression is restricted to a region called the zone of polarizing activity (ZPA), and this expression is controlled from a long distance by the cis-regulator ZRS. Here, members of two groups of ETS transcription factors are shown to act directly at the ZRS mediating a differential effect on Shh, defining its spatial expression pattern. Occupancy at multiple GABPα/ETS1 sites regulates the position of the ZPA boundary, whereas ETV4/ETV5 binding restricts expression outside the ZPA. The ETS gene family is therefore attributed with specifying the boundaries of the classical ZPA. Two point mutations within the ZRS change the profile of ETS binding and activate Shh expression at an ectopic site in the limb bud. These molecular changes define a pathogenetic mechanism that leads to preaxial polydactyly (PPD). PMID:22340503

A periodic pattern of SNPs in the human genome

PubMed Central

Madsen, Bo Eskerod; Villesen, Palle; Wiuf, Carsten

2007-01-01

By surveying a filtered, high-quality set of SNPs in the human genome, we have found that SNPs positioned 1, 2, 4, 6, or 8 bp apart are more frequent than SNPs positioned 3, 5, 7, or 9 bp apart. The observed pattern is not restricted to genomic regions that are known to cause sequencing or alignment errors, for example, transposable elements (SINE, LINE, and LTR), tandem repeats, and large duplicated regions. However, we found that the pattern is almost entirely confined to what we define as “periodic DNA.” Periodic DNA is a genomic region with a high degree of periodicity in nucleotide usage. It turned out that periodic DNA is mainly small regions (average length 16.9 bp), widely distributed in the genome. Furthermore, periodic DNA has a 1.8 times higher SNP density than the rest of the genome and SNPs inside periodic DNA have a significantly higher genotyping error rate than SNPs outside periodic DNA. Our results suggest that not all SNPs in the human genome are created by independent single nucleotide mutations, and that care should be taken in analysis of SNPs from periodic DNA. The latter may have important consequences for SNP and association studies. PMID:17673700

Defining and Mapping Mammalian Coat Pattern Genes: Multiple Genomic Regions Implicated in Domestic Cat Stripes and Spots

PubMed Central

Eizirik, Eduardo; David, Victor A.; Buckley-Beason, Valerie; Roelke, Melody E.; Schäffer, Alejandro A.; Hannah, Steven S.; Narfström, Kristina; O'Brien, Stephen J.; Menotti-Raymond, Marilyn

2010-01-01

Mammalian coat patterns (e.g., spots, stripes) are hypothesized to play important roles in camouflage and other relevant processes, yet the genetic and developmental bases for these phenotypes are completely unknown. The domestic cat, with its diversity of coat patterns, is an excellent model organism to investigate these phenomena. We have established three independent pedigrees to map the four recognized pattern variants classically considered to be specified by a single locus, Tabby; in order of dominance, these are the unpatterned agouti form called “Abyssinian” or “ticked” (Ta), followed by Spotted (Ts), Mackerel (TM), and Blotched (tb). We demonstrate that at least three different loci control the coat markings of the domestic cat. One locus, responsible for the Abyssinian form (herein termed the Ticked locus), maps to an ∼3.8-Mb region on cat chromosome B1. A second locus controls the Tabby alleles TM and tb, and maps to an ∼5-Mb genomic region on cat chromosome A1. One or more additional loci act as modifiers and create a spotted coat by altering mackerel stripes. On the basis of our results and associated observations, we hypothesize that mammalian patterned coats are formed by two distinct processes: a spatially oriented developmental mechanism that lays down a species-specific pattern of skin cell differentiation and a pigmentation-oriented mechanism that uses information from the preestablished pattern to regulate the synthesis of melanin profiles. PMID:19858284

Defining and mapping mammalian coat pattern genes: multiple genomic regions implicated in domestic cat stripes and spots.

PubMed

Eizirik, Eduardo; David, Victor A; Buckley-Beason, Valerie; Roelke, Melody E; Schäffer, Alejandro A; Hannah, Steven S; Narfström, Kristina; O'Brien, Stephen J; Menotti-Raymond, Marilyn

2010-01-01

Mammalian coat patterns (e.g., spots, stripes) are hypothesized to play important roles in camouflage and other relevant processes, yet the genetic and developmental bases for these phenotypes are completely unknown. The domestic cat, with its diversity of coat patterns, is an excellent model organism to investigate these phenomena. We have established three independent pedigrees to map the four recognized pattern variants classically considered to be specified by a single locus, Tabby; in order of dominance, these are the unpatterned agouti form called "Abyssinian" or "ticked" (T(a)), followed by Spotted (T(s)), Mackerel (T(M)), and Blotched (t(b)). We demonstrate that at least three different loci control the coat markings of the domestic cat. One locus, responsible for the Abyssinian form (herein termed the Ticked locus), maps to an approximately 3.8-Mb region on cat chromosome B1. A second locus controls the Tabby alleles T(M) and t(b), and maps to an approximately 5-Mb genomic region on cat chromosome A1. One or more additional loci act as modifiers and create a spotted coat by altering mackerel stripes. On the basis of our results and associated observations, we hypothesize that mammalian patterned coats are formed by two distinct processes: a spatially oriented developmental mechanism that lays down a species-specific pattern of skin cell differentiation and a pigmentation-oriented mechanism that uses information from the preestablished pattern to regulate the synthesis of melanin profiles.

Decoding complex flow-field patterns in visual working memory.

PubMed

Christophel, Thomas B; Haynes, John-Dylan

2014-05-01

There has been a long history of research on visual working memory. Whereas early studies have focused on the role of lateral prefrontal cortex in the storage of sensory information, this has been challenged by research in humans that has directly assessed the encoding of perceptual contents, pointing towards a role of visual and parietal regions during storage. In a previous study we used pattern classification to investigate the storage of complex visual color patterns across delay periods. This revealed coding of such contents in early visual and parietal brain regions. Here we aim to investigate whether the involvement of visual and parietal cortex is also observable for other types of complex, visuo-spatial pattern stimuli. Specifically, we used a combination of fMRI and multivariate classification to investigate the retention of complex flow-field stimuli defined by the spatial patterning of motion trajectories of random dots. Subjects were trained to memorize the precise spatial layout of these stimuli and to retain this information during an extended delay. We used a multivariate decoding approach to identify brain regions where spatial patterns of activity encoded the memorized stimuli. Content-specific memory signals were observable in motion sensitive visual area MT+ and in posterior parietal cortex that might encode spatial information in a modality independent manner. Interestingly, we also found information about the memorized visual stimulus in somatosensory cortex, suggesting a potential crossmodal contribution to memory. Our findings thus indicate that working memory storage of visual percepts might be distributed across unimodal, multimodal and even crossmodal brain regions. Copyright © 2014 Elsevier Inc. All rights reserved.

Discrete domains of gene expression in germinal layers distinguish the development of gyrencephaly

PubMed Central

de Juan Romero, Camino; Bruder, Carl; Tomasello, Ugo; Sanz-Anquela, José Miguel; Borrell, Víctor

2015-01-01

Gyrencephalic species develop folds in the cerebral cortex in a stereotypic manner, but the genetic mechanisms underlying this patterning process are unknown. We present a large-scale transcriptomic analysis of individual germinal layers in the developing cortex of the gyrencephalic ferret, comparing between regions prospective of fold and fissure. We find unique transcriptional signatures in each germinal compartment, where thousands of genes are differentially expressed between regions, including ∼80% of genes mutated in human cortical malformations. These regional differences emerge from the existence of discrete domains of gene expression, which occur at multiple locations across the developing cortex of ferret and human, but not the lissencephalic mouse. Complex expression patterns emerge late during development and map the eventual location of folds or fissures. Protomaps of gene expression within germinal layers may contribute to define cortical folds or functional areas, but our findings demonstrate that they distinguish the development of gyrencephalic cortices. PMID:25916825

A simple photometric factor in perceived depth order of bistable transparency patterns.

PubMed

Fukiage, Taiki; Oishi, Takeshi; Ikeuchi, Katsushi

2014-05-05

Previous studies on perceptual transparency defined the photometric condition in which perceived depth ordering between two surfaces becomes ambiguous. Even under this bistable transparency condition, it is known that depth-order perceptions are often biased toward one specific interpretation (Beck, Prazdny, & Ivry, 1984; Delogu, Fedorov, Belardinelli, & van Leeuwen, 2010; Kitaoka, 2005; Oyama & Nakahara, 1960). In this study, we examined what determines the perceived depth ordering for bistable transparency patterns using stimuli that simulated two partially overlapping disks resulting in four regions: a (background), b (portion of right disk), p (portion of left disk), and q (shared region). In contrast to the previous theory that proposed contributions of contrast against the background region (i.e., contrast at contour b/a and contrast at contour p/a) to perceived depth order in bistable transparency patterns, the present study demonstrated that contrast against the background region has little influence on perceived depth order compared with contrast against the shared region (i.e., contrast at contour b/q and contrast at contour p/q). In addition, we found that the perceived depth ordering is well predicted by a simpler model that takes into consideration only relative size of lightness difference against the shared region. Specifically, the probability that the left disk is perceived as being in front is proportional to (|b - q| - |p - q|) / (|b - q| + |p - q|) calculated based on lightness.

[What do functionally defined populations contribute to the explanation of regional differences in medical care?].

PubMed

Graf von Stillfried, D; Czihal, T

2014-02-01

Geographic variation in health care is increasingly subject to analysis and health policy aiming at the suitable allocation of resources and the reduction of unwarranted variation for the patient populations concerned. As in the case of area-level indicators, in most cases populations are geographically defined. The concept of geographically defined populations, however, may be self-limiting with respect to identifying the potential for improvement. As an alternative, we explored how a functional definition of populations would support defining the scope for reducing unwarranted geographical variations. Given that patients in Germany have virtually no limits in accessing physicians of their choice, we adapted a method that has been developed in the United States to create virtual networks of physicians based on commonly treated patients. Using the physician claims data under statutory insurance, which covers 90% of the population, we defined 43,006 populations-and networks-in 2010. We found that there is considerable variation between the population in terms of their risk structure and the share of the primary care practice in the total services provided. Moreover, there are marked differences in the size and structure of networks between cities, densely populated regions, and rural regions. We analyzed the variation for two area-level indicators: the proportion of diabetics with at least one HbA1c test per year for diabetics, and the proportion of patients with low back pain undergoing computed tomography and/or magnetic resonance imaging. Variation at the level of functionally defined populations proved to be larger than for geographically defined populations. The pattern of distribution gives evidence on the degree to which consensus targets could be reached and which networks need to be addressed in order to reduce unwarranted regional variation. The concept of functionally defined populations needs to be further developed before implementation.

Congruence as a measurement of extended haplotype structure across the genome

PubMed Central

2012-01-01

Background Historically, extended haplotypes have been defined using only a few data points, such as alleles for several HLA genes in the MHC. High-density SNP data, and the increasing affordability of whole genome SNP typing, creates the opportunity to define higher resolution extended haplotypes. This drives the need for new tools that support quantification and visualization of extended haplotypes as defined by as many as 2000 SNPs. Confronted with high-density SNP data across the major histocompatibility complex (MHC) for 2,300 complete families, compiled by the Type 1 Diabetes Genetics Consortium (T1DGC), we developed software for studying extended haplotypes. Methods The software, called ExHap (Extended Haplotype), uses a similarity measurement we term congruence to identify and quantify long-range allele identity. Using ExHap, we analyzed congruence in both the T1DGC data and family-phased data from the International HapMap Project. Results Congruent chromosomes from the T1DGC data have between 96.5% and 99.9% allele identity over 1,818 SNPs spanning 2.64 megabases of the MHC (HLA-DRB1 to HLA-A). Thirty-three of 132 DQ-DR-B-A defined haplotype groups have > 50% congruent chromosomes in this region. For example, 92% of chromosomes within the DR3-B8-A1 haplotype are congruent from HLA-DRB1 to HLA-A (99.8% allele identity). We also applied ExHap to all 22 autosomes for both CEU and YRI cohorts from the International HapMap Project, identifying multiple candidate extended haplotypes. Conclusions Long-range congruence is not unique to the MHC region. Patterns of allele identity on phased chromosomes provide a simple, straightforward approach to visually and quantitatively inspect complex long-range structural patterns in the genome. Such patterns aid the biologist in appreciating genetic similarities and differences across cohorts, and can lead to hypothesis generation for subsequent studies. PMID:22369243

Enc1 expression in the chick telencephalon at intermediate and late stages of development.

PubMed

García-Calero, Elena; Puelles, Luis

2009-12-10

In this work we studied the regional expression pattern of the Enc1 gene in the chick embryo telencephalon at intermediate and late stages of development, bearing on architectonic groupings and boundaries of current interest. In general, the Enc1 signal shows a markedly heterogeneous areal pattern of expression throughout the telencephalon; this corroborates data on new pallial and subpallial structures defined recently in the stereotaxic chick brain atlas of Puelles et al. (2007. The chick brain in stereotaxic coodinates. San Diego, CA: Academic Press). For example: a periventricular/central domain is Enc1-negative in the ventral pallium or nidopallium; core and shell nuclei appear in the mesopallium; the redefined caudodorsolateral area shows a characteristic pattern; the limits of the densocellular hyperpallium in the dorsal pallium are illuminated; and the postulated entorhinal cortex area is distinct at the posterior telencephalic pole. Interestingly, Enc1 transcripts are distinctly present in the piriform cortex at the surface of the ventral pallium throughout its longitudinal extent, as well as in the most rostral part of the lateral pallium, implying a layout of this cortex more similar to the situation in mammals than was assumed previously. Separate corticoid superficial strata are labeled by the Enc1 probe in the lateral and dorsal pallial regions. In the subpallium, the expression of Enc1 agrees with the new radial subdivisions defined by Puelles et al. (2007).

Spatially invariant coding of numerical information in functionally defined subregions of human parietal cortex.

PubMed

Eger, E; Pinel, P; Dehaene, S; Kleinschmidt, A

2015-05-01

Macaque electrophysiology has revealed neurons responsive to number in lateral (LIP) and ventral (VIP) intraparietal areas. Recently, fMRI pattern recognition revealed information discriminative of individual numbers in human parietal cortex but without precisely localizing the relevant sites or testing for subregions with different response profiles. Here, we defined the human functional equivalents of LIP (feLIP) and VIP (feVIP) using neurophysiologically motivated localizers. We applied multivariate pattern recognition to investigate whether both regions represent numerical information and whether number codes are position specific or invariant. In a delayed number comparison paradigm with laterally presented numerosities, parietal cortex discriminated between numerosities better than early visual cortex, and discrimination generalized across hemifields in parietal, but not early visual cortex. Activation patterns in the 2 parietal regions of interest did not differ in the coding of position-specific or position-independent number information, but in the expression of a numerical distance effect which was more pronounced in feLIP. Thus, the representation of number in parietal cortex is at least partially position invariant. Both feLIP and feVIP contain information about individual numerosities in humans, but feLIP hosts a coarser representation of numerosity than feVIP, compatible with either broader tuning or a summation code. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Ecohydrology of dry regions: storage versus pulse soil water dynamics

USGS Publications Warehouse

Lauenroth, William K.; Schlaepfer, Daniel R.; Bradford, John B.

2014-01-01

Although arid and semiarid regions are defined by low precipitation, the seasonal timing of temperature and precipitation can influence net primary production and plant functional type composition. The importance of precipitation seasonality is evident in semiarid areas of the western U.S., which comprise the Intermountain (IM) zone, a region that receives important winter precipitation and is dominated by woody plants and the Great Plains (GP), a region that receives primarily summer precipitation and is dominated by perennial grasses. Although these general relationships are well recognized, specific differences in water cycling between these regions have not been well characterized. We used a daily time step soil water simulation model and twenty sites from each region to analyze differences in soil water dynamics and ecosystem water balance. IM soil water patterns are characterized by storage of water during fall, winter, and spring resulting in relatively reliable available water during spring and early summer, particularly in deep soil layers. By contrast, GP soil water patterns are driven by pulse precipitation events during the warm season, resulting in fluctuating water availability in all soil layers. These contrasting patterns of soil water—storage versus pulse dynamics—explain important differences between the two regions. Notably, the storage dynamics of the IN sites increases water availability in deep soil layers, favoring the deeper rooted woody plants in that region, whereas the pulse dynamics of the Great Plains sites provide water primarily in surface layers, favoring the shallow-rooted grasses in that region. In addition, because water received when plants are either not active or only partially so is more vulnerable to evaporation and sublimation than water delivered during the growing season, IM ecosystems use a smaller fraction of precipitation for transpiration (47%) than GP ecosystems (49%). Recognizing the pulse-storage dichotomy in soil water regimes between the IM and GP regions may be useful for understanding the potential influence of climate changes on soil water patterns and resulting dominant plant functional groups in both regions.

The synoptic- and planetary-scale environments associated with significant 1000-hPa geostrophic wind events along the Beaufort Sea coast

NASA Astrophysics Data System (ADS)

Cooke, Melanie

The substantial interannual variability and the observed warming trend of the Beaufort Sea region are important motivators for the study of regional climate and weather there. In an attempt to further our understanding of strong wind events, which can drive sea ice dynamics and storm surges, their characteristic environments at the synoptic and planetary scales are defined and analysed using global reanalysis data. A dependency on an enhanced or suppressed Aleutian low is found. This produces either a strong southeasterly or north-westerly 1000-hPa geostrophic wind event. The characteristic mid-tropospheric patterns for these two distinct event types show similarities to the positive and negative Pacific/North American teleconnection patterns, but their correlations have yet to be assessed.

Disaster resilience and population ageing: the 1995 Kobe and 2004 Chuetsu earthquakes in Japan.

PubMed

Chen, Haili; Maki, Norio; Hayashi, Haruo

2014-04-01

This paper provides a framework for evaluating the effects of population ageing on disaster resilience. In so doing, it focuses on the 1995 Kobe and 2004 Chuetsu earthquakes, two major disasters that affected Japan before the 2011 Great East Japan earthquake. It analyses regional population recovery on the basis of pre-disaster and post-recovery demographic characteristics using defined transition patterns of population ageing. The evaluation framework demonstrates that various recovery measures make different contributions to disaster resilience for each transition pattern of population ageing. With reference to regional population ageing, the framework allows for a prediction of disaster resilience, facilitating place vulnerability assessments and potentially informing policy-making strategies for Japan and other countries with ageing populations. © 2014 The Author(s). Disasters © Overseas Development Institute, 2014.

Geographic variation in patterns of nestedness among local stream fish assemblages in Virginia

USGS Publications Warehouse

Cook, R.R.; Angermeier, P.L.; Finn, D.S.; Poff, N.L.; Krueger, K.L.

2004-01-01

Nestedness of faunal assemblages is a multiscale phenomenon, potentially influenced by a variety of factors. Prior small-scale studies have found freshwater fish species assemblages to be nested along stream courses as a result of either selective colonization or extinction. However, within-stream gradients in temperature and other factors are correlated with the distributions of many fish species and may also contribute to nestedness. At a regional level, strongly nested patterns would require a consistent set of structuring mechanisms across streams, and correlation among species' tolerances of the environmental factors that influence distribution. Thus, nestedness should be negatively associated with the spatial extent of the region analyzed and positively associated with elevational gradients (a correlate of temperature and other environmental factors). We examined these relationships for the freshwater fishes of Virginia. Regions were defined within a spatial hierarchy and included whole river drainages, portions of drainages within physiographic provinces, and smaller subdrainages. In most cases, nestedness was significantly stronger in regions of smaller spatial extent and in regions characterized by greater topographic relief. Analysis of hydrologic variability and patterns of faunal turnover provided no evidence that interannual colonization/extinction dynamics contributed to elevational differences in nestedness. These results suggest that, at regional scales, nestedness is influenced by interactions between biotic and abiotic factors, and that the strongest nestedness is likely to occur where a small number of organizational processes predominate, i.e., over small spatial extents and regions exhibiting strong environmental gradients. ?? Springer-Verlag 2004.

Self-organizing human cardiac microchambers mediated by geometric confinement

NASA Astrophysics Data System (ADS)

Ma, Zhen; Wang, Jason; Loskill, Peter; Huebsch, Nathaniel; Koo, Sangmo; Svedlund, Felicia L.; Marks, Natalie C.; Hua, Ethan W.; Grigoropoulos, Costas P.; Conklin, Bruce R.; Healy, Kevin E.

2015-07-01

Tissue morphogenesis and organ formation are the consequences of biochemical and biophysical cues that lead to cellular spatial patterning in development. To model such events in vitro, we use PEG-patterned substrates to geometrically confine human pluripotent stem cell colonies and spatially present mechanical stress. Modulation of the WNT/β-catenin pathway promotes spatial patterning via geometric confinement of the cell condensation process during epithelial-mesenchymal transition, forcing cells at the perimeter to express an OCT4+ annulus, which is coincident with a region of higher cell density and E-cadherin expression. The biochemical and biophysical cues synergistically induce self-organizing lineage specification and creation of a beating human cardiac microchamber confined by the pattern geometry. These highly defined human cardiac microchambers can be used to study aspects of embryonic spatial patterning, early cardiac development and drug-induced developmental toxicity.

Notch-signalling is required for head regeneration and tentacle patterning in Hydra.

PubMed

Münder, Sandra; Tischer, Susanne; Grundhuber, Maresa; Büchels, Nathalie; Bruckmeier, Nadine; Eckert, Stefanie; Seefeldt, Carolin A; Prexl, Andrea; Käsbauer, Tina; Böttger, Angelika

2013-11-01

Local self-activation and long ranging inhibition provide a mechanism for setting up organising regions as signalling centres for the development of structures in the surrounding tissue. The adult hydra hypostome functions as head organiser. After hydra head removal it is newly formed and complete heads can be regenerated. The molecular components of this organising region involve Wnt-signalling and β-catenin. However, it is not known how correct patterning of hypostome and tentacles are achieved in the hydra head and whether other signals in addition to HyWnt3 are needed for re-establishing the new organiser after head removal. Here we show that Notch-signalling is required for re-establishing the organiser during regeneration and that this is due to its role in restricting tentacle activation. Blocking Notch-signalling leads to the formation of irregular head structures characterised by excess tentacle tissue and aberrant expression of genes that mark the tentacle boundaries. This indicates a role for Notch-signalling in defining the tentacle pattern in the hydra head. Moreover, lateral inhibition by HvNotch and its target HyHes are required for head regeneration and without this the formation of the β-catenin/Wnt dependent head organiser is impaired. Work on prebilaterian model organisms has shown that the Wnt-pathway is important for setting up signalling centres for axial patterning in early multicellular animals. Our data suggest that the integration of Wnt-signalling with Notch-Delta activity was also involved in the evolution of defined body plans in animals. © 2013 Elsevier Inc. All rights reserved.

Analysis of Injury and Mortality Patterns in Deceased Patients with Road Traffic Injuries: An Autopsy Study.

PubMed

Pfeifer, Roman; Schick, Sylvia; Holzmann, Christopher; Graw, Matthias; Teuben, Michel; Pape, Hans-Christoph

2017-12-01

Despite improvements in prevention and rescue, mortality rates after severe blunt trauma continue to be a problem. The present study analyses mortality patterns in a representative blunt trauma population, specifically the influence of demographic, injury pattern, location and timing of death. Patients that died between 1 January 2004 and 31 December 2005 were subjected to a standardised autopsy. death from blunt trauma due to road traffic injuries (Injury Severity Score ≥ 16), patients from a defined geographical area and death on scene or in hospital. suicide, homicide, penetrating trauma and monotrauma including isolated head injury. Statistical analyses included Student's t test (parametric), Mann-Whitney U test (nonparametric) or Chi-square test. A total of 277 consecutive injured patients were included in this study (mean age 46.1 ± 23 years; 67.5% males), 40.5% of which had an ISS of 75. A unimodal distribution of mortality was observed in blunt trauma patients. The most frequently injured body regions with the highest severity were the head (38.6%), chest (26.7%), or both head and chest (11.0%). The cumulative analysis of mortality showed that several factors, such as injury pattern and regional location of collisions, also affected the pattern of mortality. The majority of patients died on scene from severe head and thoracic injuries. A homogenous distribution of death was observed after an initial peak of death on scene. Moreover, several factors such as injury pattern and regional location of collisions may also affect the pattern of mortality.

Development of a new USDA plant hardiness zone map for the United States

Treesearch

C. Daly; M.P. Widrlechner; M.D. Halbleib; J.I. Smith; W.P. Gibson

2012-01-01

In many regions of the world, the extremes of winter cold are a major determinant of the geographic distribution of perennial plant species and of their successful cultivation. In the United States, the U.S. Department of Agriculture (USDA) Plant Hardiness Zone Map (PHZM) is the primary reference for defining geospatial patterns of extreme winter cold for the...

Pattern and Epidemiology of Poisoning in the East African Region: A Literature Review

PubMed Central

Chingombe, Patience; Maredza, Mandy

2016-01-01

The establishment and strengthening of poisons centres was identified as a regional priority at the first African regional meeting on the Strategic Approach to International Chemicals Management (SAICM) in June 2006. At this meeting, the possibility of a subregional poisons centre, that is, a centre in one country serving multiple countries, was suggested. The WHO Headquarters following consultation with counterparts at the WHO Regional Office for Africa (AFRO) and the SAICM Africa Regional Focal Point successfully submitted a proposal to the SAICM Quick Start Programme (QSP) Trust Fund Committee for a feasibility study into a subregional poisons centre in the Eastern Africa subregion. However, before such a study could be conducted it was deemed necessary to carry out a literature review on the patterns and epidemiology of poisoning in this region so as to inform the feasibility study. The current paper presents the results of this literature review. The literature search was done in the months of June and July 2012 by two independent reviewers with no language or publication date restrictions using defined search terms on PUBMED. After screening, the eventual selection of articles for review and inclusion in this study was done by a third reviewer. PMID:27882048

A Functional Cartography of Cognitive Systems

PubMed Central

Mattar, Marcelo G.; Cole, Michael W.; Thompson-Schill, Sharon L.; Bassett, Danielle S.

2015-01-01

One of the most remarkable features of the human brain is its ability to adapt rapidly and efficiently to external task demands. Novel and non-routine tasks, for example, are implemented faster than structural connections can be formed. The neural underpinnings of these dynamics are far from understood. Here we develop and apply novel methods in network science to quantify how patterns of functional connectivity between brain regions reconfigure as human subjects perform 64 different tasks. By applying dynamic community detection algorithms, we identify groups of brain regions that form putative functional communities, and we uncover changes in these groups across the 64-task battery. We summarize these reconfiguration patterns by quantifying the probability that two brain regions engage in the same network community (or putative functional module) across tasks. These tools enable us to demonstrate that classically defined cognitive systems—including visual, sensorimotor, auditory, default mode, fronto-parietal, cingulo-opercular and salience systems—engage dynamically in cohesive network communities across tasks. We define the network role that a cognitive system plays in these dynamics along the following two dimensions: (i) stability vs. flexibility and (ii) connected vs. isolated. The role of each system is therefore summarized by how stably that system is recruited over the 64 tasks, and how consistently that system interacts with other systems. Using this cartography, classically defined cognitive systems can be categorized as ephemeral integrators, stable loners, and anything in between. Our results provide a new conceptual framework for understanding the dynamic integration and recruitment of cognitive systems in enabling behavioral adaptability across both task and rest conditions. This work has important implications for understanding cognitive network reconfiguration during different task sets and its relationship to cognitive effort, individual variation in cognitive performance, and fatigue. PMID:26629847

Episodic reinstatement in the medial temporal lobe.

PubMed

Staresina, Bernhard P; Henson, Richard N A; Kriegeskorte, Nikolaus; Alink, Arjen

2012-12-12

The essence of episodic memory is our ability to reexperience past events in great detail, even in the absence of external stimulus cues. Does the phenomenological reinstatement of past experiences go along with reinstating unique neural representations in the brain? And if so, how is this accomplished by the medial temporal lobe (MTL), a brain region intimately linked to episodic memory? Computational models suggest that such reinstatement (also termed "pattern completion") in cortical regions is mediated by the hippocampus, a key region of the MTL. Although recent functional magnetic resonance imaging studies demonstrated reinstatement of coarse item properties like stimulus category or task context across different brain regions, it has not yet been shown whether reinstatement can be observed at the level of individual, discrete events-arguably the defining feature of episodic memory-nor whether MTL structures like the hippocampus support this "true episodic" reinstatement. Here we show that neural activity patterns for unique word-scene combinations encountered during encoding are reinstated in human parahippocampal cortex (PhC) during retrieval. Critically, this reinstatement occurs when word-scene combinations are successfully recollected (even though the original scene is not visually presented) and does not encompass other stimulus domains (such as word-color associations). Finally, the degree of PhC reinstatement across retrieval events correlated with hippocampal activity, consistent with a role of the hippocampus in coordinating pattern completion in cortical regions.

Physical vs. photolithographic patterning of plasma polymers: an investigation by ToF-SSIMS and multivariate analysis

PubMed Central

Mishra, Gautam; Easton, Christopher D.; McArthur, Sally L.

2009-01-01

Physical and photolithographic techniques are commonly used to create chemical patterns for a range of technologies including cell culture studies, bioarrays and other biomedical applications. In this paper, we describe the fabrication of chemical micropatterns from commonly used plasma polymers. Atomic force microcopy (AFM) imaging, Time-of-Flight Static Secondary Ion Mass Spectrometry (ToF-SSIMS) imaging and multivariate analysis have been employed to visualize the chemical boundaries created by these patterning techniques and assess the spatial and chemical resolution of the patterns. ToF-SSIMS analysis demonstrated that well defined chemical and spatial boundaries were obtained from photolithographic patterning, while the resolution of physical patterning via a transmission electron microscopy (TEM) grid varied depending on the properties of the plasma system including the substrate material. In general, physical masking allowed diffusion of the plasma species below the mask and bleeding of the surface chemistries. Multivariate analysis techniques including Principal Component Analysis (PCA) and Region of Interest (ROI) assessment were used to investigate the ToF-SSIMS images of a range of different plasma polymer patterns. In the most challenging case, where two strongly reacting polymers, allylamine and acrylic acid were deposited, PCA confirmed the fabrication of micropatterns with defined spatial resolution. ROI analysis allowed for the identification of an interface between the two plasma polymers for patterns fabricated using the photolithographic technique which has been previously overlooked. This study clearly demonstrated the versatility of photolithographic patterning for the production of multichemistry plasma polymer arrays and highlighted the need for complimentary characterization and analytical techniques during the fabrication plasma polymer micropatterns. PMID:19950941

Delineating ecological regions in marine systems: Integrating physical structure and community composition to inform spatial management in the eastern Bering Sea

NASA Astrophysics Data System (ADS)

Baker, Matthew R.; Hollowed, Anne B.

2014-11-01

Characterizing spatial structure and delineating meaningful spatial boundaries have useful applications to understanding regional dynamics in marine systems, and are integral to ecosystem approaches to fisheries management. Physical structure and drivers combine with biological responses and interactions to organize marine systems in unique ways at multiple scales. We apply multivariate statistical methods to define spatially coherent ecological units or ecoregions in the eastern Bering Sea. We also illustrate a practical approach to integrate data on species distribution, habitat structure and physical forcing mechanisms to distinguish areas with distinct biogeography as one means to define management units in large marine ecosystems. We use random forests to quantify the relative importance of habitat and environmental variables to the distribution of individual species, and to quantify shifts in multispecies assemblages or community composition along environmental gradients. Threshold shifts in community composition are used to identify regions with distinct physical and biological attributes, and to evaluate the relative importance of predictor variables to determining regional boundaries. Depth, bottom temperature and frontal boundaries were dominant factors delineating distinct biological communities in this system, with a latitudinal divide at approximately 60°N. Our results indicate that distinct climatic periods will shift habitat gradients and that dynamic physical variables such as temperature and stratification are important to understanding temporal stability of ecoregion boundaries. We note distinct distribution patterns among functional guilds and also evidence for resource partitioning among individual species within each guild. By integrating physical and biological data to determine spatial patterns in community composition, we partition ecosystems along ecologically significant gradients. This may provide a basis for defining spatial management units or serve as a baseline index for analyses of structural shifts in the physical environment, species abundance and distribution, and community dynamics over time.

Decoding negative affect personality trait from patterns of brain activation to threat stimuli.

PubMed

Fernandes, Orlando; Portugal, Liana C L; Alves, Rita de Cássia S; Arruda-Sanchez, Tiago; Rao, Anil; Volchan, Eliane; Pereira, Mirtes; Oliveira, Letícia; Mourao-Miranda, Janaina

2017-01-15

Pattern recognition analysis (PRA) applied to functional magnetic resonance imaging (fMRI) has been used to decode cognitive processes and identify possible biomarkers for mental illness. In the present study, we investigated whether the positive affect (PA) or negative affect (NA) personality traits could be decoded from patterns of brain activation in response to a human threat using a healthy sample. fMRI data from 34 volunteers (15 women) were acquired during a simple motor task while the volunteers viewed a set of threat stimuli that were directed either toward them or away from them and matched neutral pictures. For each participant, contrast images from a General Linear Model (GLM) between the threat versus neutral stimuli defined the spatial patterns used as input to the regression model. We applied a multiple kernel learning (MKL) regression combining information from different brain regions hierarchically in a whole brain model to decode the NA and PA from patterns of brain activation in response to threat stimuli. The MKL model was able to decode NA but not PA from the contrast images between threat stimuli directed away versus neutral with a significance above chance. The correlation and the mean squared error (MSE) between predicted and actual NA were 0.52 (p-value=0.01) and 24.43 (p-value=0.01), respectively. The MKL pattern regression model identified a network with 37 regions that contributed to the predictions. Some of the regions were related to perception (e.g., occipital and temporal regions) while others were related to emotional evaluation (e.g., caudate and prefrontal regions). These results suggest that there was an interaction between the individuals' NA and the brain response to the threat stimuli directed away, which enabled the MKL model to decode NA from the brain patterns. To our knowledge, this is the first evidence that PRA can be used to decode a personality trait from patterns of brain activation during emotional contexts. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Typical cerebral metabolic patterns in neurodegenerative brain diseases.

PubMed

Teune, Laura K; Bartels, Anna L; de Jong, Bauke M; Willemsen, Antoon T M; Eshuis, Silvia A; de Vries, Jeroen J; van Oostrom, Joost C H; Leenders, Klaus L

2010-10-30

The differential diagnosis of neurodegenerative brain diseases on clinical grounds is difficult, especially at an early disease stage. Several studies have found specific regional differences of brain metabolism applying [(18)F]-fluoro-deoxyglucose positron emission tomography (FDG-PET), suggesting that this method can assist in early differential diagnosis of neurodegenerative brain diseases.We have studied patients who had an FDG-PET scan on clinical grounds at an early disease stage and included those with a retrospectively confirmed diagnosis according to strictly defined clinical research criteria. Ninety-six patients could be included of which 20 patients with Parkinson's disease (PD), 21 multiple system atrophy (MSA), 17 progressive supranuclear palsy (PSP), 10 corticobasal degeneration (CBD), 6 dementia with Lewy bodies (DLB), 15 Alzheimer's disease (AD), and 7 frontotemporal dementia (FTD). FDG PET images of each patient group were analyzed and compared to18 healthy controls using Statistical Parametric Mapping (SPM5).Disease-specific patterns of relatively decreased metabolic activity were found in PD (contralateral parietooccipital and frontal regions), MSA (bilateral putamen and cerebellar hemispheres), PSP (prefrontal cortex and caudate nucleus, thalamus, and mesencephalon), CBD (contralateral cortical regions), DLB (occipital and parietotemporal regions), AD (parietotemporal regions), and FTD (frontotemporal regions).The integrated method addressing a spectrum of various neurodegenerative brain diseases provided means to discriminate patient groups also at early disease stages. Clinical follow-up enabled appropriate patient inclusion. This implies that an early diagnosis in individual patients can be made by comparing each subject's metabolic findings with a complete database of specific disease related patterns.

The Evolution of Gene Regulatory Networks that Define Arthropod Body Plans.

PubMed

Auman, Tzach; Chipman, Ariel D

2017-09-01

Our understanding of the genetics of arthropod body plan development originally stems from work on Drosophila melanogaster from the late 1970s and onward. In Drosophila, there is a relatively detailed model for the network of gene interactions that proceeds in a sequential-hierarchical fashion to define the main features of the body plan. Over the years, we have a growing understanding of the networks involved in defining the body plan in an increasing number of arthropod species. It is now becoming possible to tease out the conserved aspects of these networks and to try to reconstruct their evolution. In this contribution, we focus on several key nodes of these networks, starting from early patterning in which the main axes are determined and the broad morphological domains of the embryo are defined, and on to later stage wherein the growth zone network is active in sequential addition of posterior segments. The pattern of conservation of networks is very patchy, with some key aspects being highly conserved in all arthropods and others being very labile. Many aspects of early axis patterning are highly conserved, as are some aspects of sequential segment generation. In contrast, regional patterning varies among different taxa, and some networks, such as the terminal patterning network, are only found in a limited range of taxa. The growth zone segmentation network is ancient and is probably plesiomorphic to all arthropods. In some insects, it has undergone significant modification to give rise to a more hardwired network that generates individual segments separately. In other insects and in most arthropods, the sequential segmentation network has undergone a significant amount of systems drift, wherein many of the genes have changed. However, it maintains a conserved underlying logic and function. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Controlled removal of ceramic surfaces with combination of ions implantation and ultrasonic energy

DOEpatents

Boatner, Lynn A.; Rankin, Janet; Thevenard, Paul; Romana, Laurence J.

1995-01-01

A method for tailoring or patterning the surface of ceramic articles is provided by implanting ions to predetermined depth into the ceramic material at a selected surface location with the ions being implanted at a fluence and energy adequate to damage the lattice structure of the ceramic material for bi-axially straining near-surface regions of the ceramic material to the predetermined depth. The resulting metastable near-surface regions of the ceramic material are then contacted with energy pulses from collapsing, ultrasonically-generated cavitation bubbles in a liquid medium for removing to a selected depth the ion-damaged near-surface regions containing the bi-axially strained lattice structure from the ceramic body. Additional patterning of the selected surface location on the ceramic body is provided by implanting a high fluence of high-energy, relatively-light ions at selected surface sites for relaxing the bi-axial strain in the near-surface regions defined by these sites and thereby preventing the removal of such ion-implanted sites by the energy pulses from the collapsing ultrasonic cavitation bubbles.

Persistence and long-term memories of daily maximum and minimum temperatures in southern South America

NASA Astrophysics Data System (ADS)

Naumann, Gustavo; Vargas, Walter M.; Minetti, Juan L.

2011-10-01

The persistence and long-term memories in daily maximum and minimum temperature series during the instrumental period in southern South America were analysed. Here, we found a markedly seasonal pattern both for short- and long-term memories that can lead to enhanced predictability on intraseasonal timescales. In addition, well-defined spatial patterns of these properties were found in the region. Throughout the entire region, the strongest dependence was observed in autumn and early winter. In the Patagonia region only, the temperatures exhibited more memory during the spring. In general, these elements indicate that nonlinear interactions exist between the annual cycles of temperature and its anomalies. Knowledge of the spatiotemporal behaviour of these long-term memories can be used in the building of stochastic models that only use persistence. It is possible to propose two objective forecast models based on linear interactions associated with persistence and one that allows for the use of information from nonlinear interactions that are manifested in the form of forerunners.

Travel patterns in China.

PubMed

Garske, Tini; Yu, Hongjie; Peng, Zhibin; Ye, Min; Zhou, Hang; Cheng, Xiaowen; Wu, Jiabing; Ferguson, Neil

2011-02-02

The spread of infectious disease epidemics is mediated by human travel. Yet human mobility patterns vary substantially between countries and regions. Quantifying the frequency of travel and length of journeys in well-defined population is therefore critical for predicting the likely speed and pattern of spread of emerging infectious diseases, such as a new influenza pandemic. Here we present the results of a large population survey undertaken in 2007 in two areas of China: Shenzhen city in Guangdong province, and Huangshan city in Anhui province. In each area, 10,000 randomly selected individuals were interviewed, and data on regular and occasional journeys collected. Travel behaviour was examined as a function of age, sex, economic status and home location. Women and children were generally found to travel shorter distances than men. Travel patterns in the economically developed Shenzhen region are shown to resemble those in developed and economically advanced middle income countries with a significant fraction of the population commuting over distances in excess of 50 km. Conversely, in the less developed rural region of Anhui, travel was much more local, with very few journeys over 30 km. Travel patterns in both populations were well-fitted by a gravity model with a lognormal kernel function. The results provide the first quantitative information on human travel patterns in modern China, and suggest that a pandemic emerging in a less developed area of rural China might spread geographically sufficiently slowly for containment to be feasible, while spatial spread in the more economically developed areas might be expected to be much more rapid, making containment more difficult.

Travel Patterns in China

PubMed Central

Garske, Tini; Yu, Hongjie; Peng, Zhibin; Ye, Min; Zhou, Hang; Cheng, Xiaowen; Wu, Jiabing; Ferguson, Neil

2011-01-01

The spread of infectious disease epidemics is mediated by human travel. Yet human mobility patterns vary substantially between countries and regions. Quantifying the frequency of travel and length of journeys in well-defined population is therefore critical for predicting the likely speed and pattern of spread of emerging infectious diseases, such as a new influenza pandemic. Here we present the results of a large population survey undertaken in 2007 in two areas of China: Shenzhen city in Guangdong province, and Huangshan city in Anhui province. In each area, 10,000 randomly selected individuals were interviewed, and data on regular and occasional journeys collected. Travel behaviour was examined as a function of age, sex, economic status and home location. Women and children were generally found to travel shorter distances than men. Travel patterns in the economically developed Shenzhen region are shown to resemble those in developed and economically advanced middle income countries with a significant fraction of the population commuting over distances in excess of 50 km. Conversely, in the less developed rural region of Anhui, travel was much more local, with very few journeys over 30 km. Travel patterns in both populations were well-fitted by a gravity model with a lognormal kernel function. The results provide the first quantitative information on human travel patterns in modern China, and suggest that a pandemic emerging in a less developed area of rural China might spread geographically sufficiently slowly for containment to be feasible, while spatial spread in the more economically developed areas might be expected to be much more rapid, making containment more difficult. PMID:21311745

A Building like a Tree, a Campus like a Forest: Sustainable Design Comes to New England Higher Education

ERIC Educational Resources Information Center

McDonough, William; Braungart, Michael; Dale, Diane

2002-01-01

As in other regions, development on many New England campuses over the past 30 years has tended to be more random than planned. Following the same patterns of sprawl that have defined most development in today's era, the placement of new campus buildings often separated them from the life of the university, while a hodgepodge of architectural…

Defining the "older" crash victim: the relationship between age and serious injury in motor vehicle crashes.

PubMed

Newgard, Craig D

2008-07-01

Age is often used as a predictor of injury and mortality in motor vehicle crashes (MVCs), however, the age that defines an "older" occupant in terms of injury-risk remains unclear, as do specific injury patterns associated with increasing age. The objective of this study was to evaluate the relationship between age and serious injury (including injury patterns) for occupants involved in MVCs. This was a retrospective cohort study using a national population-based cohort of adult front-seat occupants involved in MVCs and included in the National Automotive Sampling System Crashworthiness Data System database from 1995 to 2006. The primary outcome was serious injury, defined as an abbreviated injury scale (AIS) score >/=3 in any body region. Anatomic injury patterns were also assessed by age. One hundred thousand one hundred and fifty-six adult front-seat occupants were included in the analysis, of which 14,128 (2%) were seriously injured. Age was a strong predictor of serious injury using a variety of different age covariates (categorical, continuous, and polynomial) in multivariable regression models (p<0.0001 for all). There was evidence of a strong non-linear relationship between age and serious injury (p<0.001 for comparison of non-linear to linear representation of age). There was no age that clearly defined an "older" occupant by injury risk, as the odds of injury increased with increasing age across all age groups. The proportion of serious head and extremity injuries gradually increased with increasing age, while serious chest injuries markedly increased after 60 years. Age is a strong predictor of serious injury from motor vehicle trauma, the risk of which increases in non-linear fashion as age increases. There is no specific age that clearly defines an "older" occupant by injury risk.

Ultrasound of Inherited vs. Acquired Demyelinating Polyneuropathies

PubMed Central

Zaidman, Craig M.; Harms, Matthew B.; Pestronk, Alan

2013-01-01

Introduction We compared features of nerve enlargement in inherited and acquired demyelinating neuropathies using ultrasound. Methods We measured median and ulnar nerve cross-sectional areas in proximal and distal regions in 128 children and adults with inherited (Charcot-Marie Tooth-1 (CMT-1) (n=35)) and acquired (Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) (n=55), Guillaine-Barre Syndrome (GBS) (n=21) and Multifocal Motor Neuropathy (MMN) (n=17)) demyelinating neuropathies. We classified nerve enlargement by degree and number of regions affected. We defined patterns of nerve enlargement as: none- no enlargement; mild-nerves enlarged but never more than twice normal; regional- nerves normal at at least one region and enlarged more than twice normal at atleast one region; diffuse- nerves enlarged at all four regions with atleast one region more than twice normal size. Results Nerve enlargement was commonly diffuse (89%) and generally more than twice normal size in CMT-1, but not (p<0.001) in acquired disorders which mostly had either no, mild or regional nerve enlargement (CIDP (64%), GBS (95%), and MMN (100%)). In CIDP, subjects treated within three months of disease onset had less nerve enlargement than those treated later. Discussion Ultrasound identified patterns of diffuse nerve enlargement can be used to screen patients suspected of having CMT-1. Normal, mildly, or regionally enlarged nerves in demyelinating polyneuropathy suggests an acquired etiology. Early treatment in CIDP may impede nerve enlargement. PMID:24101129

Temperature extremes: geographic patterns, recent changes, and implications for organismal vulnerabilities.

PubMed

Buckley, Lauren B; Huey, Raymond B

2016-12-01

Extreme temperatures can injure or kill organisms and can drive evolutionary patterns. Many indices of extremes have been proposed, but few attempts have been made to establish geographic patterns of extremes and to evaluate whether they align with geographic patterns in biological vulnerability and diversity. To examine these issues, we adopt the CLIMDEX indices of thermal extremes. We compute scores for each index on a geographic grid during a baseline period (1961-1990) and separately for the recent period (1991-2010). Heat extremes (temperatures above the 90th percentile during the baseline period) have become substantially more common during the recent period, particularly in the tropics. Importantly, the various indices show weak geographic concordance, implying that organisms in different regions will face different forms of thermal stress. The magnitude of recent shifts in indices is largely uncorrelated with baseline scores in those indices, suggesting that organisms are likely to face novel thermal stresses. Organismal tolerances correlate roughly with absolute metrics (mainly for cold), but poorly with metrics defined relative to local conditions. Regions with high extreme scores do not correlate closely with regions with high species diversity, human population density, or agricultural production. Even though frequency and intensity of extreme temperature events have - and are likely to have - major impacts on organisms, the impacts are likely to be geographically and taxonomically idiosyncratic and difficult to predict. © 2016 John Wiley & Sons Ltd.

Establishment of embryonic neuroepithelial cell lines exhibiting an epiplastic expression pattern of region specific markers.

PubMed

Nardelli, Jeannette; Catala, Martin; Charnay, Patrick

2003-09-15

Neuroepithelial b2T cells were derived from the hindbrain and the spinal cord of mouse transgenic embryos, which expressed SV40 T antigen under the control of a Hoxb2 enhancer. Strikingly, b2T cell lines of either origin exhibit a very similar gene expression pattern, including markers of the hindbrain and the spinal cord, such as Hox genes, but not of more anterior cephalic regions. In addition, the broad expression pattern of b2T cells, probably linked to culture conditions, appeared to be appropriately modulated when the cells were reimplanted at different longitudinal levels into chick host embryos, suggesting that these cells are responsive to exogenous signalling mechanisms. Further support for these allegations was obtained by culturing b2T cells in defined medium and by assessing the expression of Krox20, an odd-numbered rhombomere marker, which appeared to be modulated by a complex interplay between FGF, retinoic acid (RA), and noggin. With respect to these as yet unique properties, b2T cells constitute an original alternative tool to in vivo models for the analysis of molecular pathways involved in the patterning of the neural tube. Copyright 2003 Wiley-Liss, Inc.

Photolithography-Based Patterning of Liquid Metal Interconnects for Monolithically Integrated Stretchable Circuits.

PubMed

Park, Chan Woo; Moon, Yu Gyeong; Seong, Hyejeong; Jung, Soon Won; Oh, Ji-Young; Na, Bock Soon; Park, Nae-Man; Lee, Sang Seok; Im, Sung Gap; Koo, Jae Bon

2016-06-22

We demonstrate a new patterning technique for gallium-based liquid metals on flat substrates, which can provide both high pattern resolution (∼20 μm) and alignment precision as required for highly integrated circuits. In a very similar manner as in the patterning of solid metal films by photolithography and lift-off processes, the liquid metal layer painted over the whole substrate area can be selectively removed by dissolving the underlying photoresist layer, leaving behind robust liquid patterns as defined by the photolithography. This quick and simple method makes it possible to integrate fine-scale interconnects with preformed devices precisely, which is indispensable for realizing monolithically integrated stretchable circuits. As a way for constructing stretchable integrated circuits, we propose a hybrid configuration composed of rigid device regions and liquid interconnects, which is constructed on a rigid substrate first but highly stretchable after being transferred onto an elastomeric substrate. This new method can be useful in various applications requiring both high-resolution and precisely aligned patterning of gallium-based liquid metals.

Skin Cancer of the Head and Neck With Perineural Invasion: Defining the Clinical Target Volumes Based on the Pattern of Failure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gluck, Iris; Ibrahim, Mohannad; Popovtzer, Aron

2009-05-01

Purpose: To analyze patterns of failure in patients with head-and-neck cutaneous squamous cell carcinoma (HNCSCC) and clinical/radiologic evidence of perineural invasion (CPNI), in order to define neural clinical target volume (CTV) for treatment planning. Methods and Materials: Patients treated with three-dimensional (3D) conformal or intensity-modulated radiotherapy (IMRT) for HNCSCC with CPNI were included in the study. A retrospective review of the clinical charts, radiotherapy (RT) plans and radiologic studies has been conducted. Results: Eleven consecutive patients with HNCSCCs with CPNI were treated from 2000 through 2007. Most patients underwent multiple surgical procedures and RT courses. The most prevalent failure patternmore » was along cranial nerves (CNs), and multiple CNs were ultimately involved in the majority of cases. In all cases the involved CNs at recurrence were the main nerves innervating the primary tumor sites, as well as their major communicating nerves. We have found several distinct patterns of disease spread along specific CNs depending on the skin regions harboring the primary tumors, including multiple branches of CN V and VII. These patterns and the pertinent anatomy are detailed in the this article. Conclusions: Predictable disease spread patterns along cranial nerves supplying the primary tumor sites were found in this study. Awareness of these patterns, as well as knowledge of the relevant cranial nerve anatomy, should be the basis for CTV definition and delineation for RT treatment planning.« less

Patterns of failure after involved field radiotherapy for locally advanced esophageal squamous cell carcinoma.

PubMed

Li, Duo-Jie; Li, Hong-Wei; He, Bin; Wang, Geng-Ming; Cai, Han-Fei; Duan, Shi-Miao; Liu, Jing-Jing; Zhang, Ya-Jun; Cui, Zhen; Jiang, Hao

2016-01-01

To retrospectively analyze the patterns of failure and the treatment effects of involved-field irradiation (IFI) on patients treated with locally advanced esophageal squamous cell carcinoma (ESCC) and to determine whether IFI is practicable in these patients. A total of 79 patients with locally advanced ESCC underwent three dimensional conformal (3D)CRT) or intensity modulated radiotherapy (IMRT) using IFI or elective nodal irradiation (ENI) according to the target volume. The patterns of failure were defined as local/regional, in-field, out)of)field regional lymph node (LN) and distant failure. With a median follow)up of 32.0 months, failures were observed in 66 (83.6%) patients. The cumulative incidence of local/regional failure (55.8 vs 52.8%) and in)field regional lymph node failure (25.6 vs 19.4%) showed no statistically significant difference between the IFI and the ENI group (p=0.526 and 0.215, respectively). Out)of)field nodal relapse rate of only 7.0% was seen in the IFI group. Three)year survival rates for the ENI and IFI group were 22.2 and 18.6%, respectively (p=0.240), and 3)year distant metastasis rates were 27.8 and 32.6%, respectively (p=0.180). The lung V10, V20, V30 and mean lung dose of the ENI group were greater than those of the IFI group, while the mean lung dose and V10 had statistically significant difference. The patterns of failure and survival rates in the IFI group were similar as in the ENI group; the regional recurrence and distant metastasis are the main cause of treatment failure. IFI is feasible for locally advanced ESCC. Further investigation is needed to increase local control and decrease distant metastasis in these patients.

Photospheric magnetic fields

NASA Technical Reports Server (NTRS)

Howard, R.

1972-01-01

Knowledge on the nature of magnetic fields on the solar surface is reviewed. At least a large part of the magnetic flux in the solar surface is confined to small bundles of lines of force within which the field strength is of the order of 500 gauss. Magnetic fields are closely associated with all types of solar activity. Magnetic flux appears at the surface at the clearly defined birth or regeneration of activity of an active region. As the region ages, the magnetic flux migrates to form large-scale patterns and the polar fields. Some manifestations of the large-scale distribution are discussed.

Trampoline metamaterial: Local resonance enhancement by springboards

NASA Astrophysics Data System (ADS)

Bilal, Osama R.; Hussein, Mahmoud I.

2013-09-01

We investigate the dispersion characteristics of locally resonant elastic metamaterials formed by the erection of pillars on the solid regions in a plate patterned by a periodic array of holes. We show that these solid regions effectively act as springboards leading to an enhanced resonance behavior by the pillars when compared to the nominal case of pillars with no holes. This local resonance amplification phenomenon, which we define as the trampoline effect, is shown to cause subwavelength bandgaps to increase in size by up to a factor of 4. This outcome facilitates the utilization of subwavelength metamaterial properties over exceedingly broad frequency ranges.

Loss of lager specific genes and subtelomeric regions define two different Saccharomyces cerevisiae lineages for Saccharomyces pastorianus Group I and II strains.

PubMed

Monerawela, Chandre; James, Tharappel C; Wolfe, Kenneth H; Bond, Ursula

2015-03-01

Lager yeasts, Saccharomyces pastorianus, are interspecies hybrids between S. cerevisiae and S. eubayanus and are classified into Group I and Group II clades. The genome of the Group II strain, Weihenstephan 34/70, contains eight so-called 'lager-specific' genes that are located in subtelomeric regions. We evaluated the origins of these genes through bioinformatic and PCR analyses of Saccharomyces genomes. We determined that four are of cerevisiae origin while four originate from S. eubayanus. The Group I yeasts contain all four S. eubayanus genes but individual strains contain only a subset of the cerevisiae genes. We identified S. cerevisiae strains that contain all four cerevisiae 'lager-specific' genes, and distinct patterns of loss of these genes in other strains. Analysis of the subtelomeric regions uncovered patterns of loss in different S. cerevisiae strains. We identify two classes of S. cerevisiae strains: ale yeasts (Foster O) and stout yeasts with patterns of 'lager-specific' genes and subtelomeric regions identical to Group I and II S. pastorianus yeasts, respectively. These findings lead us to propose that Group I and II S. pastorianus strains originate from separate hybridization events involving different S. cerevisiae lineages. Using the combined bioinformatic and PCR data, we describe a potential classification map for industrial yeasts. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.

Method for identifying subsurface fluid migration and drainage pathways in and among oil and gas reservoirs using 3-D and 4-D seismic imaging

DOEpatents

Anderson, R.N.; Boulanger, A.; Bagdonas, E.P.; Xu, L.; He, W.

1996-12-17

The invention utilizes 3-D and 4-D seismic surveys as a means of deriving information useful in petroleum exploration and reservoir management. The methods use both single seismic surveys (3-D) and multiple seismic surveys separated in time (4-D) of a region of interest to determine large scale migration pathways within sedimentary basins, and fine scale drainage structure and oil-water-gas regions within individual petroleum producing reservoirs. Such structure is identified using pattern recognition tools which define the regions of interest. The 4-D seismic data sets may be used for data completion for large scale structure where time intervals between surveys do not allow for dynamic evolution. The 4-D seismic data sets also may be used to find variations over time of small scale structure within individual reservoirs which may be used to identify petroleum drainage pathways, oil-water-gas regions and, hence, attractive drilling targets. After spatial orientation, and amplitude and frequency matching of the multiple seismic data sets, High Amplitude Event (HAE) regions consistent with the presence of petroleum are identified using seismic attribute analysis. High Amplitude Regions are grown and interconnected to establish plumbing networks on the large scale and reservoir structure on the small scale. Small scale variations over time between seismic surveys within individual reservoirs are identified and used to identify drainage patterns and bypassed petroleum to be recovered. The location of such drainage patterns and bypassed petroleum may be used to site wells. 22 figs.

Method for identifying subsurface fluid migration and drainage pathways in and among oil and gas reservoirs using 3-D and 4-D seismic imaging

DOEpatents

Anderson, Roger N.; Boulanger, Albert; Bagdonas, Edward P.; Xu, Liqing; He, Wei

1996-01-01

The invention utilizes 3-D and 4-D seismic surveys as a means of deriving information useful in petroleum exploration and reservoir management. The methods use both single seismic surveys (3-D) and multiple seismic surveys separated in time (4-D) of a region of interest to determine large scale migration pathways within sedimentary basins, and fine scale drainage structure and oil-water-gas regions within individual petroleum producing reservoirs. Such structure is identified using pattern recognition tools which define the regions of interest. The 4-D seismic data sets may be used for data completion for large scale structure where time intervals between surveys do not allow for dynamic evolution. The 4-D seismic data sets also may be used to find variations over time of small scale structure within individual reservoirs which may be used to identify petroleum drainage pathways, oil-water-gas regions and, hence, attractive drilling targets. After spatial orientation, and amplitude and frequency matching of the multiple seismic data sets, High Amplitude Event (HAE) regions consistent with the presence of petroleum are identified using seismic attribute analysis. High Amplitude Regions are grown and interconnected to establish plumbing networks on the large scale and reservoir structure on the small scale. Small scale variations over time between seismic surveys within individual reservoirs are identified and used to identify drainage patterns and bypassed petroleum to be recovered. The location of such drainage patterns and bypassed petroleum may be used to site wells.

Phylogenetic patterns in populations of Chilean species of the genus Orestias (Teleostei: Cyprinodontidae): results of mitochondrial DNA analysis.

PubMed

Lüssen, Arne; Falk, Thomas M; Villwock, Wolfgang

2003-10-01

Patterns of molecular genetic differentiation among taxa of the "agassii species complex" (Parenti, 1984) were analysed based on partial mtDNA control region sequences. Special attention has been paid to Chilean populations of Orestias agassii and species from isolated lakes of northern Chile, e.g., O. agassii, Orestias chungarensis, Orestias parinacotensis, Orestias laucaensis, and Orestias ascotanensis. Orestias tschudii, Orestias luteus, and Orestias ispi were analysed comparatively. Our findings support the utility of mtDNA control region sequences for phylogenetic studies within the "agassii species complex" and confirmed the monophyly of this particular lineage, excluding O. luteus. However, the monophyly of further morphologically defined lineages within the "agassii complex" appears doubtful. No support was found for the utility of these data sets for inferring phylogenetic relationships between more distantly related taxa originating from Lake Titicaca.

Intra Oral Fibrosarcoma with Various Histopathological Patterns: A Rare Case Report

PubMed Central

Reddy, A. Vikram Simha; Prakash, A. Ravi; Ram, V. Sai; Thorati, Rukmini Swathi

2015-01-01

Fibrosarcoma has been defined as a malignant mesenchymal tumour, the cells of which recapitulate the appearance of the normal fibroblast, with variable collagen production. Fibrosarcoma is a very uncommon tumour in the head and neck regions constituting only 0.05% of all the fibrosarcomas presenting in humans. They cause no characteristic symptoms and pose difficulty in clinical diagnosis. They have been classified histologically based on their distinct features into myxoid fibrosarcoma, low grade fibromyxoid fibrosarcoma and sclerosing epitheloid sarcoma. Here we present a rare case report of a 45-year-old male patient presenting with a maxillary fibrosarcoma, which histologically presented with different patterns. PMID:26393135

Winter temperatures over the Korean Peninsula and East Asia: development of a new index and its application to seasonal forecast

NASA Astrophysics Data System (ADS)

Kim, Seon Tae; Sohn, Soo-Jin; Kug, Jong-Seong

2017-09-01

This study proposes a new index for monitoring and predicting winter temperatures of the Korean Peninsula based on the dominant atmospheric winter teleconnection patterns. The utilization of this index is further extended to the East Asian Winter Monsoon (EAWM) index because the new index is found to well represent the main feature of the EAWM circulation. Among the teleconnection patterns, the East Atlantic (EA) and Western Pacific (WP) patterns are found to be most strongly correlated with winter temperatures via their partial association with changes in sea level pressure (SLP) around the Korean Peninsula, i.e., the EA and WP patterns are associated with SLP variation over the Siberian High region and the Kuroshio extension region to the east of Japan, respectively. On the basis of this relationship, the two regions representing the northwest-to-southeast SLP gradients are determined to define the new index. It is found that the new index can represent the Korean winter temperatures consistently well regardless of their considerable decadal changes. When compared with the existing SLP-based EAWM indices, the new index shows the best performance in delineating winter air temperatures, not only in the Korean Peninsula but also in the entire East Asian region. We also assess the prediction skill of the new index with seasonal coupled forecast models of the APEC Climate Center of Korea and its capability to predict winter temperatures. This assessment shows that the new index has potential for operationally predicting and monitoring winter temperatures in Korea and the whole of East Asia.

Distinct endothelial phenotypes evoked by arterial waveforms derived from atherosclerosis-susceptible and -resistant regions of human vasculature

NASA Astrophysics Data System (ADS)

Dai, Guohao; Kaazempur-Mofrad, Mohammad R.; Natarajan, Sripriya; Zhang, Yuzhi; Vaughn, Saran; Blackman, Brett R.; Kamm, Roger D.; García-Cardeña, Guillermo; Gimbrone, Michael A., Jr.

2004-10-01

Atherosclerotic lesion localization to regions of disturbed flow within certain arterial geometries, in humans and experimental animals, suggests an important role for local hemodynamic forces in atherogenesis. To explore how endothelial cells (EC) acquire functional/dysfunctional phenotypes in response to vascular region-specific flow patterns, we have used an in vitro dynamic flow system to accurately reproduce arterial shear stress waveforms on cultured human EC and have examined the effects on EC gene expression by using a high-throughput transcriptional profiling approach. The flow patterns in the carotid artery bifurcations of several normal human subjects were characterized by using 3D flow analysis based on actual vascular geometries and blood flow profiles. Two prototypic arterial waveforms, "athero-prone" and "athero-protective," were defined as representative of the wall shear stresses in two distinct regions of the carotid artery (carotid sinus and distal internal carotid artery) that are typically "susceptible" or "resistant," respectively, to atherosclerotic lesion development. These two waveforms were applied to cultured EC, and cDNA microarrays were used to analyze the differential patterns of EC gene expression. In addition, the differential effects of athero-prone vs. athero-protective waveforms were further characterized on several parameters of EC structure and function, including actin cytoskeletal organization, expression and localization of junctional proteins, activation of the NF-B transcriptional pathway, and expression of proinflammatory cytokines and adhesion molecules. These global gene expression patterns and functional data reveal a distinct phenotypic modulation in response to the wall shear stresses present in atherosclerosis-susceptible vs. atherosclerosis-resistant human arterial geometries.

Determinants of the distribution and severity of hypoperfusion in patients with ischemic stroke.

PubMed

Bang, O Y; Saver, J L; Alger, J R; Starkman, S; Ovbiagele, B; Liebeskind, D S

2008-11-25

In acute cerebral ischemia, two variables characterize the extent of hypoperfusion: the volume of hypoperfused tissue and the intensity of hypoperfusion within these regions. We evaluated the determinants of the intensity of hypoperfusion within oligemic regions among patients who were eligible for recanalization therapy for acute ischemic stroke. We analyzed data, including pretreatment diffusion-weighted imaging (DWI) and perfusion-weighted imaging, on 119 patients with acute middle cerebral artery infarctions. The intensity of hypoperfusion within oligemic regions was characterized by the hypoperfusion intensity ratio (HIR), defined as the volume of tissue with severe hypoperfusion (Tmax > or = 8 seconds) divided by the volume of tissue with any hypoperfusion (Tmax > or = 2 seconds). Based on the DWI data, we divided the patients into four stroke phenotypes: large cortical, small (< 1 cm diameter) cortical, border-zone, and deep pattern. The mean (SD) volume of severe hypoperfusion was 54.6 (52.5) mL, and that of any hypoperfusion was 140.8 (81.3) mL. The HIR ranged widely, from 0.002 to 0.974, with a median of 0.35 (interquartile range 0.13-0.60). The volume of any hypoperfusion did not predict the intensity of hypoperfusion within the affected region (r = 0.10, p = 0.284). Angiographic collateral flow grade was associated with HIRs (p value for trend = 0.019) and differed among DWI lesion patterns. In multivariate analysis, diastolic pressure on admission (odds ratio 0.959, 95% CI 0.922-0.998) and DWI pattern of deep infarcts (odds ratio 18.004 compared with large cortical pattern, 95% CI 1.855-173.807) were independently associated with a low HIR. The intensity of hypoperfusion within an oligemic field is largely independent of the size of the oligemia region. Predictors of lesser intensity of hypoperfusion are lower diastolic blood pressure and presence of a deep diffusion-weighted imaging lesion pattern.

High-fidelity phase and amplitude control of phase-only computer generated holograms using conjugate gradient minimisation.

PubMed

Bowman, D; Harte, T L; Chardonnet, V; De Groot, C; Denny, S J; Le Goc, G; Anderson, M; Ireland, P; Cassettari, D; Bruce, G D

2017-05-15

We demonstrate simultaneous control of both the phase and amplitude of light using a conjugate gradient minimisation-based hologram calculation technique and a single phase-only spatial light modulator (SLM). A cost function, which incorporates the inner product of the light field with a chosen target field within a defined measure region, is efficiently minimised to create high fidelity patterns in the Fourier plane of the SLM. A fidelity of F = 0.999997 is achieved for a pattern resembling an LG10 mode with a calculated light-usage efficiency of 41.5%. Possible applications of our method in optical trapping and ultracold atoms are presented and we show uncorrected experimental realisation of our patterns with F = 0.97 and 7.8% light efficiency.

Computer prediction of dual reflector antenna radiation properties

NASA Technical Reports Server (NTRS)

Christodoulou, C.

1981-01-01

A program for calculating radiation patterns for reflector antennas with either smooth analytic surfaces or with surfaces composed of a number of panels. Techniques based on the geometrical optics (GO) approach were used in tracing rays over the following regions: from a feed antenna to the first reflector surface (subreflector); from this reflector to a larger reflector surface (main reflector); and from the main reflector to a mathematical plane (aperture plane) in front of the main reflector. The equations of GO were also used to calculate the reflected field components for each ray making use of the feed radiation pattern and the parameters defining the surfaces of the two reflectors. These resulting fields form an aperture distribution which is integrated numerically to compute the radiation pattern for a specified set of angles.

Multiple cues add up in defining a figure on a ground.

PubMed

Devinck, Frédéric; Spillmann, Lothar

2013-01-25

We studied the contribution of multiple cues to figure-ground segregation. Convexity, symmetry, and top-down polarity (henceforth called wide base) were used as cues. Single-cue displays as well as ambiguous stimulus patterns containing two or three cues were presented. Error rate (defined by responses to uncued stimuli) and reaction time were used to quantify the figural strength of a given cue. In the first experiment, observers were asked to report which of two regions, left or right, appeared as foreground figure. Error rate did not benefit from adding additional cues if convexity was present, suggesting that responses were based on convexity as the predominant figural determinant. However, reaction time became shorter with additional cues even if convexity was present. For example, when symmetry and wide base were added, figure-ground segregation was facilitated. In a second experiment, stimulus patterns were exposed for 150ms to rule out eye movements. Results were similar to those found in the first experiment. Both experiments suggest that under the conditions of our experiment figure-ground segregation is perceived more readily, when several cues cooperate in defining the figure. Copyright © 2012 Elsevier Ltd. All rights reserved.

The niche, biogeography and species interactions

PubMed Central

Wiens, John J.

2011-01-01

In this paper, I review the relevance of the niche to biogeography, and what biogeography may tell us about the niche. The niche is defined as the combination of abiotic and biotic conditions where a species can persist. I argue that most biogeographic patterns are created by niche differences over space, and that even ‘geographic barriers’ must have an ecological basis. However, we know little about specific ecological factors underlying most biogeographic patterns. Some evidence supports the importance of abiotic factors, whereas few examples exist of large-scale patterns created by biotic interactions. I also show how incorporating biogeography may offer new perspectives on resource-related niches and species interactions. Several examples demonstrate that even after a major evolutionary radiation within a region, the region can still be invaded by ecologically similar species from another clade, countering the long-standing idea that communities and regions are generally ‘saturated’ with species. I also describe the somewhat paradoxical situation where competition seems to limit trait evolution in a group, but does not prevent co-occurrence of species with similar values for that trait (called here the ‘competition–divergence–co-occurrence conundrum’). In general, the interface of biogeography and ecology could be a major area for research in both fields. PMID:21768150

Automatic classification of canine PRG neuronal discharge patterns using K-means clustering.

PubMed

Zuperku, Edward J; Prkic, Ivana; Stucke, Astrid G; Miller, Justin R; Hopp, Francis A; Stuth, Eckehard A

2015-02-01

Respiratory-related neurons in the parabrachial-Kölliker-Fuse (PB-KF) region of the pons play a key role in the control of breathing. The neuronal activities of these pontine respiratory group (PRG) neurons exhibit a variety of inspiratory (I), expiratory (E), phase spanning and non-respiratory related (NRM) discharge patterns. Due to the variety of patterns, it can be difficult to classify them into distinct subgroups according to their discharge contours. This report presents a method that automatically classifies neurons according to their discharge patterns and derives an average subgroup contour of each class. It is based on the K-means clustering technique and it is implemented via SigmaPlot User-Defined transform scripts. The discharge patterns of 135 canine PRG neurons were classified into seven distinct subgroups. Additional methods for choosing the optimal number of clusters are described. Analysis of the results suggests that the K-means clustering method offers a robust objective means of both automatically categorizing neuron patterns and establishing the underlying archetypical contours of subtypes based on the discharge patterns of group of neurons. Published by Elsevier B.V.

Efficiency index: a new parameter to define breathing patterns during dynamic Xe-127 ventilation studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Slosman, D.; Susskind, H.; Bossuyt, A.

1986-03-01

Ventilation imaging can be improved by gating scintigraphic data with the respiratory cycle using temporal Fourier analysis (TFA) to quantify the temporal behavior of the ventilation. Sixteen consecutive images, representing equal-time increments of an average respiratory cycle, were produced by TFA in the posterior view on a pixel-by-pixel basis. An Efficiency Index (EFF), defined as the ratio of the summation of all the differences between maximum and minimum counts for each pixel to that for the entire lung during the respiratory cycle, was derived to describe the pattern of ventilation. The gated ventilation studies were carried out with Xe-127 inmore » 12 subjects: normal lung function (4), small airway disease (2), COPD (5), and restrictive disease (1). EFF for the first three harmonics correlated linearly with FEV1 (r = 0.701, p< 0.01). This approach is suggested as a very sensitive method to quantify the extent and regional distribution of airway obstruction.« less

Defining Functional Areas in Individual Human Brains using Resting Functional Connectivity MRI

PubMed Central

Cohen, Alexander L.; Fair, Damien A.; Dosenbach, Nico U.F.; Miezin, Francis M.; Dierker, Donna; Van Essen, David C.; Schlaggar, Bradley L.; Petersen, Steven E.

2009-01-01

The cerebral cortex is anatomically organized at many physical scales starting at the level of single neurons and extending up to functional systems. Current functional magnetic resonance imaging (fMRI) studies often focus at the level of areas, networks, and systems. Except in restricted domains, (e.g. topographically-organized sensory regions), it is difficult to determine area boundaries in the human brain using fMRI. The ability to delineate functional areas non-invasively would enhance the quality of many experimental analyses allowing more accurate across-subject comparisons of independently identified functional areas. Correlations in spontaneous BOLD activity, often referred to as resting state functional connectivity (rs-fcMRI), are especially promising as a way to accurately localize differences in patterns of correlated activity across large expanses of cortex. In the current report, we applied a novel set of image analysis tools to explore the utility of rs-fcMRI for defining wide-ranging functional area boundaries. We find that rs-fcMRI patterns show sharp transitions in correlation patterns and that these putative areal boundaries can be reliably detected in individual subjects as well as in group data. Additionally, combining surface-based analysis techniques with image processing algorithms allows automated mapping of putative areal boundaries across large expanses of cortex without the need for prior information about a region’s function or topography. Our approach reliably produces maps of bounded regions appropriate in size and number for putative functional areas. These findings will hopefully stimulate further methodological refinements and validations. PMID:18367410

A framework for delineating the regional boundaries of PM2.5 pollution: A case study of China.

PubMed

Liu, Jianzheng; Li, Weifeng; Wu, Jiansheng

2018-04-01

Fine particulate matter (PM 2.5 ) pollution has been a major issue in many countries. Considerable studies have demonstrated that PM 2.5 pollution is a regional issue, but little research has been done to investigate the regional extent of PM 2.5 pollution or to define areas in which PM 2.5 pollutants interact. To allow for a better understanding of the regional nature and spatial patterns of PM 2.5 pollution, This study proposes a novel framework for delineating regional boundaries of PM 2.5 pollution. The framework consists of four steps, including cross-correlation analysis, time-series clustering, generation of Voronoi polygons, and polygon smoothing using polynomial approximation with exponential kernel method. Using the framework, the regional PM 2.5 boundaries for China are produced and the boundaries define areas where the monthly PM 2.5 time series of any two cities show, on average, more than 50% similarity with each other. These areas demonstrate straightforwardly that PM 2.5 pollution is not limited to a single city or a single province. We also found that the PM 2.5 areas in China tend to be larger in cold months, but more fragmented in warm months, suggesting that, in cold months, the interactions between PM 2.5 concentrations in adjacent cities are stronger than in warmer months. The proposed framework provides a tool to delineate PM 2.5 boundaries and identify areas where PM 2.5 pollutants interact. It can help define air pollution management zones and assess impacts related to PM 2.5 pollution. It can also be used in analyses of other air pollutants. Copyright © 2017 Elsevier Ltd. All rights reserved.

The spatial and temporal expression of Ch-en, the engrailed gene in the polychaete Chaetopterus, does not support a role in body axis segmentation

NASA Technical Reports Server (NTRS)

Seaver, E. C.; Paulson, D. A.; Irvine, S. Q.; Martindale, M. Q.

2001-01-01

We are interested in understanding whether the annelids and arthropods shared a common segmented ancestor and have approached this question by characterizing the expression pattern of the segment polarity gene engrailed (en) in a basal annelid, the polychaete Chaetopterus. We have isolated an en gene, Ch-en, from a Chaetopterus cDNA library. Genomic Southern blotting suggests that this is the only en class gene in this animal. The predicted protein sequence of the 1.2-kb cDNA clone contains all five domains characteristic of en proteins in other taxa, including the en class homeobox. Whole-mount in situ hybridization reveals that Ch-en is expressed throughout larval life in a complex spatial and temporal pattern. The Ch-en transcript is initially detected in a small number of neurons associated with the apical organ and in the posterior portion of the prototrochophore. At later stages, Ch-en is expressed in distinct patterns in the three segmented body regions (A, B, and C) of Chaetopterus. In all segments, Ch-en is expressed in a small set of segmentally iterated cells in the CNS. In the A region, Ch-en is also expressed in a small group of mesodermal cells at the base of the chaetal sacs. In the B region, Ch-en is initially expressed broadly in the mesoderm that then resolves into one band/segment coincident with morphological segmentation. The mesodermal expression in the B region is located in the anterior region of each segment, as defined by the position of ganglia in the ventral nerve cord, and is involved in the morphogenesis of segment-specific feeding structures late in larval life. We observe banded mesodermal and ectodermal staining in an anterior-posterior sequence in the C region. We do not observe a segment polarity pattern of expression of Ch-en in the ectoderm, as is observed in arthropods. Copyright 2001 Academic Press.

Seismotectonics of the 2014 Chiang Rai, Thailand, earthquake sequence

NASA Astrophysics Data System (ADS)

Pananont, P.; Herman, M. W.; Pornsopin, P.; Furlong, K. P.; Habangkaem, S.; Waldhauser, F.; Wongwai, W.; Limpisawad, S.; Warnitchai, P.; Kosuwan, S.; Wechbunthung, B.

2017-08-01

On 5 May 2014, a Mw 6.2 strike-slip earthquake occurred in the Mae Lao region of Chiang Rai province in Thailand. This earthquake took place in a region of known faults and caused substantial damage and injuries, although the region had been previously identified as having a relatively low earthquake hazard. Detailed field reconnaissance and deployment of a dense, temporary, network of broadband seismometers allowed details of the damage and its relationship to seismicity to be analyzed. The aftershock sequence associated with this main shock occurs on two well-defined trends, reflecting the two potential fault planes in earthquake mechanisms for the main shock and the majority of the aftershocks. The damage area was relatively large for an event of this magnitude, but building damage was largely limited to the primary rupture region, while liquefaction and other ground failure are spatially associated with the rupture area and along regional rivers. Stress modeling, combined with the time series and pattern of aftershock activity, leads us to propose that slip near the northern termination of the main shock rupture continued slightly onto a conjugate fault, helping to trigger the distinct pattern of two discrete, conjugate trends of aftershock activity that mirror the kinematics of the main shock fault mechanism.

Associations among Wine Grape Microbiome, Metabolome, and Fermentation Behavior Suggest Microbial Contribution to Regional Wine Characteristics

PubMed Central

Bokulich, Nicholas A.; Collins, Thomas S.; Masarweh, Chad; Allen, Greg; Heymann, Hildegarde; Ebeler, Susan E.

2016-01-01

ABSTRACT Regionally distinct wine characteristics (terroir) are an important aspect of wine production and consumer appreciation. Microbial activity is an integral part of wine production, and grape and wine microbiota present regionally defined patterns associated with vineyard and climatic conditions, but the degree to which these microbial patterns associate with the chemical composition of wine is unclear. Through a longitudinal survey of over 200 commercial wine fermentations, we demonstrate that both grape microbiota and wine metabolite profiles distinguish viticultural area designations and individual vineyards within Napa and Sonoma Counties, California. Associations among wine microbiota and fermentation characteristics suggest new links between microbiota, fermentation performance, and wine properties. The bacterial and fungal consortia of wine fermentations, composed from vineyard and winery sources, correlate with the chemical composition of the finished wines and predict metabolite abundances in finished wines using machine learning models. The use of postharvest microbiota as an early predictor of wine chemical composition is unprecedented and potentially poses a new paradigm for quality control of agricultural products. These findings add further evidence that microbial activity is associated with wine terroir. PMID:27302757

Enhanced local tomography

DOEpatents

Katsevich, Alexander J.; Ramm, Alexander G.

1996-01-01

Local tomography is enhanced to determine the location and value of a discontinuity between a first internal density of an object and a second density of a region within the object. A beam of radiation is directed in a predetermined pattern through the region of the object containing the discontinuity. Relative attenuation data of the beam is determined within the predetermined pattern having a first data component that includes attenuation data through the region. In a first method for evaluating the value of the discontinuity, the relative attenuation data is inputted to a local tomography function .function..sub..LAMBDA. to define the location S of the density discontinuity. The asymptotic behavior of .function..sub..LAMBDA. is determined in a neighborhood of S, and the value for the discontinuity is estimated from the asymptotic behavior of .function..sub..LAMBDA.. In a second method for evaluating the value of the discontinuity, a gradient value for a mollified local tomography function .gradient..function..sub..LAMBDA..epsilon. (x.sub.ij) is determined along the discontinuity; and the value of the jump of the density across the discontinuity curve (or surface) S is estimated from the gradient values.

Magnetic-film atom chip with 10 μm period lattices of microtraps for quantum information science with Rydberg atoms.

PubMed

Leung, V Y F; Pijn, D R M; Schlatter, H; Torralbo-Campo, L; La Rooij, A L; Mulder, G B; Naber, J; Soudijn, M L; Tauschinsky, A; Abarbanel, C; Hadad, B; Golan, E; Folman, R; Spreeuw, R J C

2014-05-01

We describe the fabrication and construction of a setup for creating lattices of magnetic microtraps for ultracold atoms on an atom chip. The lattice is defined by lithographic patterning of a permanent magnetic film. Patterned magnetic-film atom chips enable a large variety of trapping geometries over a wide range of length scales. We demonstrate an atom chip with a lattice constant of 10 μm, suitable for experiments in quantum information science employing the interaction between atoms in highly excited Rydberg energy levels. The active trapping region contains lattice regions with square and hexagonal symmetry, with the two regions joined at an interface. A structure of macroscopic wires, cutout of a silver foil, was mounted under the atom chip in order to load ultracold (87)Rb atoms into the microtraps. We demonstrate loading of atoms into the square and hexagonal lattice sections simultaneously and show resolved imaging of individual lattice sites. Magnetic-film lattices on atom chips provide a versatile platform for experiments with ultracold atoms, in particular for quantum information science and quantum simulation.

Extreme weather events and environmental contamination are associated with case-clusters of melioidosis in the Northern Territory of Australia.

PubMed

Cheng, Allen C; Jacups, Susan P; Gal, Daniel; Mayo, Mark; Currie, Bart J

2006-04-01

Melioidosis, the infection due to the environmental organism Burkholderia pseudomallei, is endemic to northern Australia and South East Asia. It is associated with exposure to mud and pooled surface water, but environmental determinants of this disease are poorly understood. We defined case-clusters in northern Australia, determined their contribution to the observed rate of melioidosis, and explored clinical features and associated environmental factors. Using geographical information systems data, we examined clustering of melioidosis cases in time and geographical space in the Top End of the Northern Territory of Australia between 1990 and 2002 using a scan statistic. DNA macrorestriction analysis, resolved by pulsed field gel electrophoresis, was performed on isolates from patients. We defined five case-clusters involving 27 patients that occurred within 7-28 days and/or a radius of 100-300 km. Clustered cases were associated with extreme weather events or environmental contamination; no difference in the clinical pattern of disease was noted from other patients not involved in clusters. Isolates from patients linked to environmental contamination were caused by isolates with similar DNA macrorestriction patterns, but isolates from patients linked to severe weather events had more diverse DNA macrorestriction patterns. Case-clusters of melioidosis where isolates exhibit diverse DNA macrorestriction patterns in our region are linked to extreme weather events and outbreaks where isolates are predominantly of the same DNA macrorestriction pattern are linked with contamination of an environmental source.

An imprinted non-coding genomic cluster at 14q32 defines clinically relevant molecular subtypes in osteosarcoma across multiple independent datasets.

PubMed

Hill, Katherine E; Kelly, Andrew D; Kuijjer, Marieke L; Barry, William; Rattani, Ahmed; Garbutt, Cassandra C; Kissick, Haydn; Janeway, Katherine; Perez-Atayde, Antonio; Goldsmith, Jeffrey; Gebhardt, Mark C; Arredouani, Mohamed S; Cote, Greg; Hornicek, Francis; Choy, Edwin; Duan, Zhenfeng; Quackenbush, John; Haibe-Kains, Benjamin; Spentzos, Dimitrios

2017-05-15

A microRNA (miRNA) collection on the imprinted 14q32 MEG3 region has been associated with outcome in osteosarcoma. We assessed the clinical utility of this miRNA set and their association with methylation status. We integrated coding and non-coding RNA data from three independent annotated clinical osteosarcoma cohorts (n = 65, n = 27, and n = 25) and miRNA and methylation data from one in vitro (19 cell lines) and one clinical (NCI Therapeutically Applicable Research to Generate Effective Treatments (TARGET) osteosarcoma dataset, n = 80) dataset. We used time-dependent receiver operating characteristic (tdROC) analysis to evaluate the clinical value of candidate miRNA profiles and machine learning approaches to compare the coding and non-coding transcriptional programs of high- and low-risk osteosarcoma tumors and high- versus low-aggressiveness cell lines. In the cell line and TARGET datasets, we also studied the methylation patterns of the MEG3 imprinting control region on 14q32 and their association with miRNA expression and tumor aggressiveness. In the tdROC analysis, miRNA sets on 14q32 showed strong discriminatory power for recurrence and survival in the three clinical datasets. High- or low-risk tumor classification was robust to using different microRNA sets or classification methods. Machine learning approaches showed that genome-wide miRNA profiles and miRNA regulatory networks were quite different between the two outcome groups and mRNA profiles categorized the samples in a manner concordant with the miRNAs, suggesting potential molecular subtypes. Further, miRNA expression patterns were reproducible in comparing high-aggressiveness versus low-aggressiveness cell lines. Methylation patterns in the MEG3 differentially methylated region (DMR) also distinguished high-aggressiveness from low-aggressiveness cell lines and were associated with expression of several 14q32 miRNAs in both the cell lines and the large TARGET clinical dataset. Within the limits of available CpG array coverage, we observed a potential methylation-sensitive regulation of the non-coding RNA cluster by CTCF, a known enhancer-blocking factor. Loss of imprinting/methylation changes in the 14q32 non-coding region defines reproducible previously unrecognized osteosarcoma subtypes with distinct transcriptional programs and biologic and clinical behavior. Future studies will define the precise relationship between 14q32 imprinting, non-coding RNA expression, genomic enhancer binding, and tumor aggressiveness, with possible therapeutic implications for both early- and advanced-stage patients.

Patterns of nodal metastases on 18F-FDG PET/CT in patients with esophageal squamous cell carcinoma are useful to guide treatment planning of radiotherapy.

PubMed

Liu, Chia-Ju; Cheng, Jason Chia-Hsien; Lee, Jang-Ming; Cheng, Mei-Fang; Tzen, Kai-Yuan; Yen, Ruoh-Fang

2015-05-01

The aim of the study was to examine the patterns of lymph node metastases from esophageal squamous cell carcinoma (ESCC) and compare the laterality of lymphatic metastasis in cervical, supraclavicular, and paratracheal areas using F-FDG PET/CT. The data of 75 patients who underwent F-FDG PET/CT for staging of ESCC between January 2011 and March 2012 were reviewed. Fourteen groups of lymph nodes from the neck to abdomen were defined. Lateralization of the upper thoracic lymph nodes was defined in reference to the midline of the trachea. Frequencies of positive lymph nodes were used to determine the pattern of lymphatic spread and compare the lateralization of metastases in the cervical and upper thoracic regions. The right paratracheal region was the most frequent site of metastasis among all patients. Left paratracheal and paragastric nodes were more frequent in upper and lower third ESCC, respectively. Upward and downward lymphatic spread was equal in mid third ESCC. In all patients, there was a trend toward more frequent lymph node metastasis on the right side than the left side for the supraclavicular and paratracheal regions. Further stratified analysis with tumor location found that right paratracheal node metastasis was significantly associated with mid third ESCC (P = 0.03). Remote nodal metastasis was found in 10.5% of patients with upper third ESCC and 13% of patients with lower third ESCC, respectively. Remote nodal metastasis was associated with higher SUV of the primary tumor (P = 0.02) and worse survival (P = 0.03). Receiver operating characteristic analysis showed a cutoff SUV of 14.8 for predicting remote lymph node metastases. PET/CT provides important information before radiotherapy planning. Mid and lower third ESCC tends to metastasize to the right paratracheal/supraclavicular lymph nodes. Remote nodal metastases on PET/CT correlated with higher primary tumor SUV and worse survival.

Associations among Wine Grape Microbiome, Metabolome, and Fermentation Behavior Suggest Microbial Contribution to Regional Wine Characteristics.

PubMed

Bokulich, Nicholas A; Collins, Thomas S; Masarweh, Chad; Allen, Greg; Heymann, Hildegarde; Ebeler, Susan E; Mills, David A

2016-06-14

Regionally distinct wine characteristics (terroir) are an important aspect of wine production and consumer appreciation. Microbial activity is an integral part of wine production, and grape and wine microbiota present regionally defined patterns associated with vineyard and climatic conditions, but the degree to which these microbial patterns associate with the chemical composition of wine is unclear. Through a longitudinal survey of over 200 commercial wine fermentations, we demonstrate that both grape microbiota and wine metabolite profiles distinguish viticultural area designations and individual vineyards within Napa and Sonoma Counties, California. Associations among wine microbiota and fermentation characteristics suggest new links between microbiota, fermentation performance, and wine properties. The bacterial and fungal consortia of wine fermentations, composed from vineyard and winery sources, correlate with the chemical composition of the finished wines and predict metabolite abundances in finished wines using machine learning models. The use of postharvest microbiota as an early predictor of wine chemical composition is unprecedented and potentially poses a new paradigm for quality control of agricultural products. These findings add further evidence that microbial activity is associated with wine terroir Wine production is a multi-billion-dollar global industry for which microbial control and wine chemical composition are crucial aspects of quality. Terroir is an important feature of consumer appreciation and wine culture, but the many factors that contribute to terroir are nebulous. We show that grape and wine microbiota exhibit regional patterns that correlate with wine chemical composition, suggesting that the grape microbiome may influence terroir In addition to enriching our understanding of how growing region and wine properties interact, this may provide further economic incentive for agricultural and enological practices that maintain regional microbial biodiversity. Copyright © 2016 Bokulich et al.

Strong Gradients in Forest Sensitivity to Climate Change Revealed by Dynamics of Forest Fire Cycles in the Post Little Ice Age Era

NASA Astrophysics Data System (ADS)

Drobyshev, Igor; Bergeron, Yves; Girardin, Martin P.; Gauthier, Sylvie; Ols, Clémentine; Ojal, John

2017-10-01

The length of the fire cycle is a critical factor affecting the vegetation cover in boreal and temperate regions. However, its responses to climate change remain poorly understood. We reanalyzed data from earlier studies of forest age structures at the landscape level, in order to map the evolution of regional fire cycles across Eastern North American boreal and temperate forests, following the termination of the Little Ice Age (LIA). We demonstrated a well-defined spatial pattern of post-LIA changes in the length of fire cycles toward lower fire activity during the 1800s and 1900s. The western section of Eastern North America (west of 77°W) experienced a decline in fire activity as early as the first half of the 1800s. By contrast, the eastern section showed these declines as late as the early 1900s. During a regionally fire-prone period of the 1910s-1920s, forests in the western section of Eastern boreal North America burned more than forests in the eastern section. The climate appeared to dominate over vegetation composition and human impacts in shaping the geographical pattern of the post-LIA change in fire activity. Changes in the atmospheric circulation patterns following the termination of the LIA, specifically changes in Arctic Oscillation and the strengthening of the Continental Polar Trough, were likely drivers of the regional fire dynamics.

Isolation of a transcription factor expressed in neural crest from the region of 22q11 deleted in DiGeorge syndrome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wadey, R.; Roberts, C.; Daw, S.

1994-09-01

Deletions within chromosome 22q11 cause a wide variety of birth defects including DiGeorge syndrome and Shprintzen syndrome. We have defined a commonly deleted region of over 2 Mb, and a critical region of 300 kb. A gene, TUPLE1, has been isolated from this critical region encoding a transcriptional regulator similar to the yeast HIR1 histone regulator gene. Since it has been suggested that DGS results from a defective neural crest, the expression of Tuple1 was examined in whole mouse and chick embryos, tissue sections and neural tube explants: Tuple1 is expressed in a dynamic pattern with high levels in regionsmore » containing migrating crest. Prior to crest migration Tuple1 is expressed in a rhombomere-specific expression pattern. Later Tuple1 is expressed in discrete domains within the developing neural tube. A remarkable feature of the experiments was the detection of a similar dynamic pattern with sense probe; i.e., there is an antisense Tuple1 transcript. This was confirmed using RPA. Tuple1 is being screened for mutations in non-deletion patients and constructs assembled for homologous recombination in ES cells. Tuple1 maps to MMU16 extending the homology of linkage with human chromosome 22. From these data we predict that the human homologue of the murine scid mutation maps to 22q11.« less

Effects of Age, Gender and Hemispheric Location on T2 Hypointensity in the Pulvinar at 3T.

PubMed

White, Matthew L; Zhang, Yan; Helvey, Jason T; Yu, Fang; Omojola, Matthew F

2014-12-01

Pulvinar signal intensity decrease on T2-weighted images has been reported in some neurological abnormalities. We aimed to define the normal T2 signal hypointensity pattern present in the pulvinar to avoid erroneous radiological interpretation. One hundred and forty-two subjects (54 men and 88 women; age range 9-91 years) with unremarkable brain 3T MR findings were enrolled. MR images were analyzed with regard to signal intensity of the pulvinar relative to the thalamus on fluid attenuated inversion recovery images. Effects of age, gender and hemispheric location on the degree of T2 hypointensity were statistically analyzed. The statistical association was measured between the pattern of signal changes in the pulvinar region and that in the putamen and the globus pallidus. We detected a linear signal decrease in the pulvinar region with age. The male subjects had a more rapid decrease of signal with age than female subjects. The right pulvinar region had a higher chance of hypointensity compared to the left. A positive linear association was found when signal change from the pulvinar region was compared with signal in the putamen and globus pallidus. We detected a linear signal decrease with age in the pulvinar. The physiological signal features of the pulvinar also depend on gender and hemispheric lateralization. The pattern of signal change in the pulvinar is similar to but not the same as that in the putamen and globus pallidus.

Functional connectivity of task context representations in prefrontal nodes of the multiple demand network.

PubMed

Stiers, Peter; Goulas, Alexandros

2018-06-01

A subset of regions in the lateral and medial prefrontal cortex and the anterior insula increase their activity level whenever a cognitive task becomes more demanding, regardless of the specific nature of this demand. During execution of a task, these areas and the surrounding cortex temporally encode aspects of the task context in spatially distributed patterns of activity. It is not clear whether these patterns reflect underlying anatomical subnetworks that still exist when task execution has finished. We use fMRI in 12 participants performing alternating blocks of three cognitive tasks to address this question. A first data set is used to define multiple demand regions in each participant. A second dataset from the same participants is used to determine multiple demand voxel assemblies with a preference for one task over the others. We then show that these voxels remain functionally coupled during execution of non-preferred tasks and that they exhibit stronger functional connectivity during rest. This indicates that the assemblies of task preference sharing voxels reflect patterns of underlying anatomical connections. Moreover, we show that voxels preferring the same task have more similar whole brain functional connectivity profiles that are consistent across participants. This suggests that voxel assemblies differ in patterns of input-output connections, most likely reflecting task demand-specific information exchange.

Snowfall in the Northwest Iberian Peninsula: Synoptic Circulation Patterns and Their Influence on Snow Day Trends

PubMed Central

Merino, Andrés; Fernández, Sergio; Hermida, Lucía; López, Laura; Sánchez, José Luis; García-Ortega, Eduardo; Gascón, Estíbaliz

2014-01-01

In recent decades, a decrease in snowfall attributed to the effects of global warming (among other causes) has become evident. However, it is reasonable to investigate meteorological causes for such decrease, by analyzing changes in synoptic scale patterns. On the Iberian Peninsula, the Castilla y León region in the northwest consists of a central plateau surrounded by mountain ranges. This creates snowfalls that are considered both an important water resource and a transportation risk. In this work, we develop a classification of synoptic situations that produced important snowfalls at observation stations in the major cities of Castilla y León from 1960 to 2011. We used principal component analysis (PCA) and cluster techniques to define four synoptic patterns conducive to snowfall in the region. Once we confirmed homogeneity of the series and serial correlation of the snowfallday records at the stations from 1960 to 2011, we carried out a Mann-Kendall test. The results show a negative trend at most stations, so there are a decreased number of snowfall days. Finally, variations in these meteorological variables were related to changes in the frequencies of snow events belonging to each synoptic pattern favorable for snowfall production at the observatory locations. PMID:25152912

Mesopause Horizontal wind estimates based on AIM CIPS polar mesospheric cloud pattern matching

NASA Astrophysics Data System (ADS)

Rong, P.; Yue, J.; Russell, J. M.; Gong, J.; Wu, D. L.; Randall, C. E.

2013-12-01

A cloud pattern matching approach is used to estimate horizontal winds in the mesopause region using Polar Mesospheric Cloud (PMC) albedo data measured by the Cloud Imaging and Particle Size instrument on the AIM satellite. Measurements for all 15 orbits per day throughout July 2007 are used to achieve statistical significance. For each orbit, eighteen out of the twenty-seven scenes are used for the pattern matching operation. Some scenes at the lower latitudes are not included because there is barely any cloud coverage for these scenes. The frame-size chosen is about 12 degrees in longitude and 3 degrees in latitude. There is no strict criterion in choosing the frame size since PMCs are widespread in the polar region and most local patterns do not have a clearly defined boundary. The frame moves at a step of 1/6th of the frame size in both the longitudinal and latitudinal directions to achieve as many 'snap-shots' as possible. A 70% correlation is used as a criterion to define an acceptable match between two patterns at two time frames; in this case the time difference is about 3.6 minutes that spans every 5 'bowtie' scenes. A 70% criterion appears weak if the chosen pattern is expected to act like a tracer. It is known that PMC brightness varies rapidly with a changing temperature and water vapor environment or changing nucleation conditions, especially on smaller spatial scales; therefore PMC patterns are not ideal tracers. Nevertheless, within a short time span such as 3.6 minutes a 70% correlation is sufficient to identify two cloud patterns that come from the same source region, although the two patterns may exhibit a significant difference in the actual brightness. Analysis of a large number of matched cloud patterns indicates that over the 3.6-minute time span about 70% of the patterns remain in the same locations. Given the 25-km2 horizontal resolution of CIPS data, this suggests that the overall magnitude of horizontal wind at PMC altitudes (~80-87 km) in the polar summer cannot exceed 25 m/s. In other words, the wind detection resolution is no better than 25 m/s. There are about 10% of cases in which it appears that an easterly prevails, with a peak value at about 80-100m/s. In another 5% of cases a westerly appears to prevail. The remaining 15% cases are related to either invalid cloud features with poor background correction or the situation in which the matching occurs at the corners of the bowties. The AIM CIPS cloud pattern matching results overall suggest that higher wind speed (25-200 m/s) can be reached occasionally, while in a majority of cases the wind advection caused albedo change is much smaller than the in-situ albedo change. However, we must note that this analysis was a feasibility study and the short period analyzed may not be representative of the winds over a seasonal time scale or the multiple-year average.

A clade of Listeria monocytogenes serotype 4b variant strains linked to recent listeriosis outbreaks associated with produce from a defined geographic region in the US.

PubMed

Burall, Laurel S; Grim, Christopher J; Datta, Atin R

2017-01-01

Four listeriosis incidences/outbreaks, spanning 19 months, have been linked to Listeria monocytogenes serotype 4b variant (4bV) strains. Three of these incidents can be linked to a defined geographical region, while the fourth is likely to be linked. In this study, whole genome sequencing (WGS) of strains from these incidents was used for genomic comparisons using two approached. The first was JSpecies tetramer, which analyzed tetranucleotide frequency to assess relatedness. The second, the CFSAN SNP Pipeline, was used to perform WGS SNP analyses against three different reference genomes to evaluate relatedness by SNP distances. In each case, unrelated strains were included as controls. The analyses showed that strains from these incidents form a highly related clade with SNP differences of ≤101 within the clade and >9000 against other strains. Multi-Virulence-Locus Sequence Typing, a third standardized approach for evaluation relatedness, was used to assess the genetic drift in six conserved, known virulence loci and showed a different clustering pattern indicating possible differences in selection pressure experienced by these genes. These data suggest a high degree of relatedness among these 4bV strains linked to a defined geographic region and also highlight the possibility of alterations related to adaptation and virulence.

Specification of regional intestinal stem cell identity during Drosophila metamorphosis.

PubMed

Driver, Ian; Ohlstein, Benjamin

2014-05-01

In the adult Drosophila midgut the bone morphogenetic protein (BMP) signaling pathway is required to specify and maintain the acid-secreting region of the midgut known as the copper cell region (CCR). BMP signaling is also involved in the modulation of intestinal stem cell (ISC) proliferation in response to injury. How ISCs are able to respond to the same signaling pathway in a regionally different manner is currently unknown. Here, we show that dual use of the BMP signaling pathway in the midgut is possible because BMP signals are only capable of transforming ISC and enterocyte identity during a defined window of metamorphosis. ISC heterogeneity is established prior to adulthood and then maintained in cooperation with regional signals from surrounding tissue. Our data provide a conceptual framework for how other tissues maintained by regional stem cells might be patterned and establishes the pupal and adult midgut as a novel genetic platform for identifying genes necessary for regional stem cell specification and maintenance.

Inter-comparison of weather and circulation type classifications for hydrological drought development

NASA Astrophysics Data System (ADS)

Fleig, Anne K.; Tallaksen, Lena M.; Hisdal, Hege; Stahl, Kerstin; Hannah, David M.

Classifications of weather and circulation patterns are often applied in research seeking to relate atmospheric state to surface environmental phenomena. However, numerous procedures have been applied to define the patterns, thus limiting comparability between studies. The COST733 Action “ Harmonisation and Applications of Weather Type Classifications for European regions” tests 73 different weather type classifications (WTC) and their associate weather types (WTs) and compares the WTCs’ utility for various applications. The objective of this study is to evaluate the potential of these WTCs for analysis of regional hydrological drought development in north-western Europe. Hydrological drought is defined in terms of a Regional Drought Area Index (RDAI), which is based on deficits derived from daily river flow series. RDAI series (1964-2001) were calculated for four homogeneous regions in Great Britain and two in Denmark. For each region, WTs associated with hydrological drought development were identified based on antecedent and concurrent WT-frequencies for major drought events. The utility of the different WTCs for the study of hydrological drought development was evaluated, and the influence of WTC attributes, i.e. input variables, number of defined WTs and general classification concept, on WTC performance was assessed. The objective Grosswetterlagen (OGWL), the objective Second-Generation Lamb Weather Type Classification (LWT2) with 18 WTs and two implementations of the objective Wetterlagenklassifikation (WLK; with 40 and 28 WTs) outperformed all other WTCs. In general, WTCs with more WTs (⩾27) were found to perform better than WTCs with less (⩽18) WTs. The influence of input variables was not consistent across the different classification procedures, and the performance of a WTC was determined primarily by the classification procedure itself. Overall, classification procedures following the relatively simple general classification concept of predefining WTs based on thresholds, performed better than those based on more sophisticated classification concepts such as deriving WTs by cluster analysis or artificial neural networks. In particular, PCA based WTCs with 9 WTs and automated WTCs with a high number of predefined WTs (subjectively and threshold based) performed well. It is suggested that the explicit consideration of the air flow characteristics of meridionality, zonality and cyclonicity in the definition of WTs is a useful feature for a WTC when analysing regional hydrological drought development.

Regional Crustal Structures and Their Relationship to the Distribution of Ore Deposits in the Western United States, Based on Magnetic and Gravity Data

USGS Publications Warehouse

Hildenbrand, T.G.; Berger, B.; Jachens, R.C.; Ludington, S.

2000-01-01

Upgraded gravity and magnetic databases and associated filtered-anomaly maps of western United States define regional crustal fractures or faults that may have guided the emplacement of plutonic rocks and large metallic ore deposits. Fractures, igneous intrusions, and hydrothermal circulation tend to be localized along boundaries of crustal blocks, with geophysical expressions that are enhanced here by wavelength filtering. In particular, we explore the utility of regional gravity and magnetic data to aid in understanding the distribution of large Mesozoic and Cenozoic ore deposits, primarily epithermal and porphyry precious and base metal deposits and sediment-hosted gold deposits in the western United States cordillera. On the broadest scale, most ore deposits lie within areas characterized by low magnetic properties. The Mesozoic Mother Lodge gold belt displays characteristic geophysical signatures (regional gravity high, regional low-to-moderate background magnetic field anomaly, and long curvilinear magnetic highs) that might serve as an exploration guide. Geophysical lineaments characterize the Idaho-Montana porphyry belt and the La Caridad-Mineral Park belt (from northern Mexico to western Arizona) and thus indicate a deep-seated control for these mineral belts. Large metal accumulations represented by the giant Bingham porphyry copper and the Butte polymetallic vein and porphyry copper systems lie at intersections of several geophysical lineaments. At a more local scale, geophysical data define deep-rooted faults and magmatic zones that correspond to patterns of epithermal precious metal deposits in western and northern Nevada. Of particular interest is an interpreted dense crustal block with a shape that resembles the elliptical deposit pattern partly formed by the Carlin trend and the Battle Mountain-Eureka mineral belt. We support previous studies, which on a local scale, conclude that structural elements work together to localize mineral deposits within regional zones or belts. This study of mineral deposits of the western United States demonstrates the ability of magnetic and gravity data to elucidate the regional geologic framework or structural setting and to contribute in locating favorable environments for hydrothermal mineralization.

RSV Hospitalizations in Comparison With Regional RSV Activity and Inpatient Palivizumab Administration, 2010-2013.

PubMed

Glick, Alexander F; Kjelleren, Stephanie; Hofstetter, Annika M; Subramony, Anupama

2017-05-01

To compare pediatric respiratory syncytial virus (RSV) hospitalizations in the United States to regional RSV activity and inpatient palivizumab administration. We characterized inpatients, excluding newborns, with RSV from the Pediatric Health Information System (July 2010-June 2013). RSV regional activity timing was defined by the National Respiratory and Enteric Virus Surveillance System. RSV hospitalization season (defined by at least 3 SDs more than the mean regional baseline number of RSV hospitalizations for 3 consecutive weeks) was compared with RSV regional activity season (2 consecutive weeks with ≥10% RSV-positive testing). Logistic regression was used to determine predictors of hospitalization timing (ie, during or outside of regional activity season). We also assessed the timing of inpatient palivizumab administration. There were 50 157 RSV hospitalizations. Mean RSV hospitalization season onset (early November) was 3.3 (SD 2.1) weeks before regional activity season onset (early December). Hospitalization season offset (early May) was 4.4 (SD 2.4) weeks after activity season offset (mid-April). RSV hospitalization and activity seasons lasted 18 to 32 and 13 to 23 weeks, respectively. Nearly 10% of hospitalizations occurred outside of regional activity season (regional ranges: 5.6%-22.4%). Children with chronic conditions were more likely to be hospitalized after regional activity season, whereas African American children were more likely to be hospitalized before. Inpatient palivizumab dosing was typically initiated before the start of RSV hospitalizations. There is regional variation in RSV hospitalization and activity patterns. Many RSV hospitalizations occur before regional activity season; high-risk infants may require RSV immunoprophylaxis sooner. Copyright © 2017 by the American Academy of Pediatrics.

Regionalizing Africa: Patterns of Precipitation Variability in Observations and Global Climate Models

NASA Technical Reports Server (NTRS)

Badr, Hamada S.; Dezfuli, Amin K.; Zaitchik, Benjamin F.; Peters-Lidard, Christa D.

2016-01-01

Many studies have documented dramatic climatic and environmental changes that have affected Africa over different time scales. These studies often raise questions regarding the spatial extent and regional connectivity of changes inferred from observations and proxies and/or derived from climate models. Objective regionalization offers a tool for addressing these questions. To demonstrate this potential, applications of hierarchical climate regionalizations of Africa using observations and GCM historical simulations and future projections are presented. First, Africa is regionalized based on interannual precipitation variability using Climate Hazards Group Infrared Precipitation with Stations (CHIRPS) data for the period 19812014. A number of data processing techniques and clustering algorithms are tested to ensure a robust definition of climate regions. These regionalization results highlight the seasonal and even month-to-month specificity of regional climate associations across the continent, emphasizing the need to consider time of year as well as research question when defining a coherent region for climate analysis. CHIRPS regions are then compared to those of five GCMs for the historic period, with a focus on boreal summer. Results show that some GCMs capture the climatic coherence of the Sahel and associated teleconnections in a manner that is similar to observations, while other models break the Sahel into uncorrelated subregions or produce a Sahel-like region of variability that is spatially displaced from observations. Finally, shifts in climate regions under projected twenty-first-century climate change for different GCMs and emissions pathways are examined. A projected change is found in the coherence of the Sahel, in which the western and eastern Sahel become distinct regions with different teleconnections. This pattern is most pronounced in high-emissions scenarios.

Spectrum of Rift Valley Fever Virus Transmission in Kenya: Insights from three Distinct Regions

PubMed Central

Labeaud, A. Desiree; Ochiai, Yoshitsugu; Peters, C.J.; Muchiri, Eric M.; King, Charles H.

2008-01-01

Rift Valley fever virus (RVFV) is an emerging pathogen that maintains high biodefense priority based on its threat to livestock, its ability to cause human hemorrhagic fever, and its potential for aerosol spread. To define the range of human transmission during inter-epidemic and epidemic periods in Kenya, we tested archived sera from defined populations (N = 1,263) for anti-RVFV IgG by ELISA and plaque reduction neutralization testing. RVFV seroprevalence was 10.8% overall and varied significantly by location, sex, and age. In NW Kenya, high seroprevalence among those born before 1980 indicates that an undetected epidemic may have occurred then. Seroconversion documented in highland areas suggests previously unsuspected inter-epidemic transmission. RVFV seroprevalence is strikingly high in certain Kenyan areas, suggesting endemic transmission patterns that may preclude accurate estimation of regional acute outbreak incidence. The extent of both epidemic and inter-epidemic RVFV transmission in Kenya is greater than previously documented. PMID:17488893

Fluvial Channel Networks as Analogs for the Ridge-forming Unit, Sinus Meridiani, Mars

NASA Astrophysics Data System (ADS)

Wilkinson, M. J.; Dubois, J. B.

2010-12-01

Fluvial models have been generally discounted as analogs for the younger layered rock units of Sinus Meridiani. A fluvial model based on the large fluvial fan provides a possibly close analog for various features of the sinuous ridges of the etched, ridge-forming unit (RFU) in particular. The close spacing of the RFU ridges, their apparently chaotic orientations, and their organization in dense networks all appear unlike classical stream channel patterns. However, drainage patterns on large fluvial fans—low-angle, fluvial aggradational features, 100s of km long, documented worldwide by us—provide parallels. Some large fan characteristics resemble those of classical floodplains, but many differences have been demonstrated. One major distinction relevant to the RFU is that channel landscapes of large fans can dominate large areas (1.2 million km2 in one S. American study area). We compare channel morphologies on large fans in the southern Sahara Desert with ridge patterns in Sinus Meridiani (fig 1). Stream channels are the dominant landform on large terrestrial fans: they may equate to the ubiquitous, sinuous, elongated ridges of the RFU that cover areas region wide. Networks of convergent/divergent and crossing channels may equate to similar features in the ridge networks. Downslope divergence is absent in channels of terrestrial upland erosional landscapes (fig. 1, left), whereas it is common to both large fans (fig. 1, center) and RFU ridge patterns (fig 1, right—downslope defined as the regional NW slope of Sinus Meridiani). RFU ridge orientation, judged from those areas apparently devoid of impact crater control, is broadly parallel with the regional slope (arrow, fig. 1, right), as is mean orientation of major channels on large fans (arrow, fig. 1, center). High densities per unit area characterize fan channels and martian ridges—reaching an order of magnitude higher than those in uplands just upstream of the terrestrial study areas—fig. 1. In concert with several other regional features, these morphological similarities argue for the RFU as a possibly fluvial unit. Figure 1. Channel patterns in Saharan upland and lowland landscapes, compared to RFU ridge patterns. Left panel—southern Sudan uplands (ctr 11.1N 28.4E); center panel—part of a large fan, Muglad basin, immediately downstream of sediment-source upland shown in left panel (10.15N 28.6E); right panel—discontinuous inverted ridge patterns, Mars (ctr 2.1N 1.0W). Arrows show direction of regional stream flow (left, center panels) and regional slope in Mars study area (right panel). North to top.

Synoptic typing: interdisciplinary application methods with three practical hydroclimatological examples

NASA Astrophysics Data System (ADS)

Siegert, C. M.; Leathers, D. J.; Levia, D. F.

2017-05-01

Synoptic classification is a methodology that represents diverse atmospheric variables and allows researchers to relate large-scale atmospheric circulation patterns to regional- and small-scale terrestrial processes. Synoptic classification has often been applied to questions concerning the surface environment. However, full applicability has been under-utilized to date, especially in disciplines such as hydroclimatology, which are intimately linked to atmospheric inputs. This paper aims to (1) outline the development of a daily synoptic calendar for the Mid-Atlantic (USA), (2) define seasonal synoptic patterns occurring in the region, and (3) provide hydroclimatological examples whereby the cascading response of precipitation characteristics, soil moisture, and streamflow are explained by synoptic classification. Together, achievement of these objectives serves as a guide for development and use of a synoptic calendar for hydroclimatological studies. In total 22 unique synoptic types were identified, derived from a combination of 12 types occurring in the winter (DJF), 13 in spring (MAM), 9 in summer (JJA), and 11 in autumn (SON). This includes six low pressure systems, four high pressure systems, one cold front, three north/northwest flow regimes, three south/southwest flow regimes, and five weakly defined regimes. Pairwise comparisons indicated that 84.3 % had significantly different rainfall magnitudes, 86.4 % had different rainfall durations, and 84.7 % had different rainfall intensities. The largest precipitation-producing classifications were not restricted to low pressure systems, but rather to patterns with access to moisture sources from the Atlantic Ocean and easterly (on-shore) winds, which transport moisture inland. These same classifications resulted in comparable rates of soil moisture recharge and streamflow discharge, illustrating the applicability of synoptic classification for a range of hydroclimatological research objectives.

Juvenile Steller sea lion (Eumetopias jubatus) utilization distributions in the Gulf of Alaska.

PubMed

Bishop, Amanda; Brown, Casey; Rehberg, Michael; Torres, Leigh; Horning, Markus

2018-01-01

A utilization distribution quantifies the temporal and spatial probability of space use for individuals or populations. These patterns in movement arise from individuals' internal state and from their response to the external environment, and thus can provide insights for assessing factors associated with the management of threatened populations. The Western Distinct Population Segment of the Steller sea lion ( Eumetopias jubatus ) has declined to approximately 20% of levels encountered 40 years ago. At the height of the decline, juvenile survival appeared to be depressed and currently there is evidence that juvenile mortality due to predation may be constraining recovery in some regions. Therefore, our objectives were to identify what spaces are biologically important to juvenile Steller sea lions in the Kenai Fjords and Prince William Sound regions of the Gulf of Alaska. We examined geospatial location data from juvenile sea lions tagged between 2000 and 2014 ( n  = 84) and derived individual and pooled-population utilization distributions (UDs) from their movements. Core areas were defined from the UDs using an individual-based approach; this quantitatively confirmed that all individuals in our sample exhibited concentrated use within their home range (95% UD). Finally, we explored if variation in UD characteristics were associated with sex, season, age, or region. We found evidence that individual juvenile home ranges were region and sex-specific, with males having larger home ranges on average. Core space characteristics were also sex-specific, and exhibited seasonal patterns of reduced size, increased proximity to haulouts, and increased intensity of use in the summer, but only in the Kenai Fjords-Gulf of Alaska region. This study highlights the areas of biological importance during this vulnerable life history stage, and the demographic, seasonal, and spatial factors associated with variation in movement patterns for a marine mesopredator. This can be useful information for promoting species recovery, and for future efforts to understand ecological patterns such as predator-prey interactions.

A comparative study of linear and nonlinear anomaly detectors for hyperspectral imagery

NASA Astrophysics Data System (ADS)

Goldberg, Hirsh; Nasrabadi, Nasser M.

2007-04-01

In this paper we implement various linear and nonlinear subspace-based anomaly detectors for hyperspectral imagery. First, a dual window technique is used to separate the local area around each pixel into two regions - an inner-window region (IWR) and an outer-window region (OWR). Pixel spectra from each region are projected onto a subspace which is defined by projection bases that can be generated in several ways. Here we use three common pattern classification techniques (Principal Component Analysis (PCA), Fisher Linear Discriminant (FLD) Analysis, and the Eigenspace Separation Transform (EST)) to generate projection vectors. In addition to these three algorithms, the well-known Reed-Xiaoli (RX) anomaly detector is also implemented. Each of the four linear methods is then implicitly defined in a high- (possibly infinite-) dimensional feature space by using a nonlinear mapping associated with a kernel function. Using a common machine-learning technique known as the kernel trick all dot products in the feature space are replaced with a Mercer kernel function defined in terms of the original input data space. To determine how anomalous a given pixel is, we then project the current test pixel spectra and the spectral mean vector of the OWR onto the linear and nonlinear projection vectors in order to exploit the statistical differences between the IWR and OWR pixels. Anomalies are detected if the separation of the projection of the current test pixel spectra and the OWR mean spectra are greater than a certain threshold. Comparisons are made using receiver operating characteristics (ROC) curves.

Generation of attosecond electron beams in relativistic ionization by short laser pulses

NASA Astrophysics Data System (ADS)

Cajiao Vélez, F.; Kamiński, J. Z.; Krajewska, K.

2018-03-01

Ionization by relativistically intense short laser pulses is studied in the framework of strong-field quantum electrodynamics. Distinctive patterns are found in the energy probability distributions of photoelectrons, which are sensitive to the properties of a driving laser field. It is demonstrated that these electrons are generated in the form of solitary attosecond wave packets. This is particularly important in light of various applications of attosecond electron beams such as in ultrafast electron diffraction and crystallography, or in time-resolved electron microscopy of physical, chemical, and biological processes. We also show that, for intense laser pulses, high-energy ionization takes place in narrow regions surrounding the momentum spiral, the exact form of which is determined by the shape of a driving pulse. The self-intersections of the spiral define the momenta for which the interference patterns in the energy distributions of photoelectrons are observed. Furthermore, these interference regions lead to the synthesis of single-electron wave packets characterized by coherent double-hump structures.

A regulatory toolbox of MiniPromoters to drive selective expression in the brain.

PubMed

Portales-Casamar, Elodie; Swanson, Douglas J; Liu, Li; de Leeuw, Charles N; Banks, Kathleen G; Ho Sui, Shannan J; Fulton, Debra L; Ali, Johar; Amirabbasi, Mahsa; Arenillas, David J; Babyak, Nazar; Black, Sonia F; Bonaguro, Russell J; Brauer, Erich; Candido, Tara R; Castellarin, Mauro; Chen, Jing; Chen, Ying; Cheng, Jason C Y; Chopra, Vik; Docking, T Roderick; Dreolini, Lisa; D'Souza, Cletus A; Flynn, Erin K; Glenn, Randy; Hatakka, Kristi; Hearty, Taryn G; Imanian, Behzad; Jiang, Steven; Khorasan-zadeh, Shadi; Komljenovic, Ivana; Laprise, Stéphanie; Liao, Nancy Y; Lim, Jonathan S; Lithwick, Stuart; Liu, Flora; Liu, Jun; Lu, Meifen; McConechy, Melissa; McLeod, Andrea J; Milisavljevic, Marko; Mis, Jacek; O'Connor, Katie; Palma, Betty; Palmquist, Diana L; Schmouth, Jean-François; Swanson, Magdalena I; Tam, Bonny; Ticoll, Amy; Turner, Jenna L; Varhol, Richard; Vermeulen, Jenny; Watkins, Russell F; Wilson, Gary; Wong, Bibiana K Y; Wong, Siaw H; Wong, Tony Y T; Yang, George S; Ypsilanti, Athena R; Jones, Steven J M; Holt, Robert A; Goldowitz, Daniel; Wasserman, Wyeth W; Simpson, Elizabeth M

2010-09-21

The Pleiades Promoter Project integrates genomewide bioinformatics with large-scale knockin mouse production and histological examination of expression patterns to develop MiniPromoters and related tools designed to study and treat the brain by directed gene expression. Genes with brain expression patterns of interest are subjected to bioinformatic analysis to delineate candidate regulatory regions, which are then incorporated into a panel of compact human MiniPromoters to drive expression to brain regions and cell types of interest. Using single-copy, homologous-recombination "knockins" in embryonic stem cells, each MiniPromoter reporter is integrated immediately 5' of the Hprt locus in the mouse genome. MiniPromoter expression profiles are characterized in differentiation assays of the transgenic cells or in mouse brains following transgenic mouse production. Histological examination of adult brains, eyes, and spinal cords for reporter gene activity is coupled to costaining with cell-type-specific markers to define expression. The publicly available Pleiades MiniPromoter Project is a key resource to facilitate research on brain development and therapies.

Discovering Coherent Structures Using Local Causal States

NASA Astrophysics Data System (ADS)

Rupe, Adam; Crutchfield, James P.; Kashinath, Karthik; Prabhat, Mr.

2017-11-01

Coherent structures were introduced in the study of fluid dynamics and were initially defined as regions characterized by high levels of coherent vorticity, i.e. regions where instantaneously space and phase correlated vorticity are high. In a more general spatiotemporal setting, coherent structures can be seen as localized broken symmetries which persist in time. Building off the computational mechanics framework, which integrates tools from computation and information theory to capture pattern and structure in nonlinear dynamical systems, we introduce a theory of coherent structures, in the more general sense. Central to computational mechanics is the causal equivalence relation, and a local spatiotemporal generalization of it is used to construct the local causal states, which are utilized to uncover a system's spatiotemporal symmetries. Coherent structures are then identified as persistent, localized deviations from these symmetries. We illustrate how novel patterns and structures can be discovered in cellular automata and outline the path from them to laminar, transitional and turbulent flows. Funded by Intel through the Big Data Center at LBNL and the IPCC at UC Davis.

ExtraTrain: a database of Extragenic regions and Transcriptional information in prokaryotic organisms

PubMed Central

Pareja, Eduardo; Pareja-Tobes, Pablo; Manrique, Marina; Pareja-Tobes, Eduardo; Bonal, Javier; Tobes, Raquel

2006-01-01

Background Transcriptional regulation processes are the principal mechanisms of adaptation in prokaryotes. In these processes, the regulatory proteins and the regulatory DNA signals located in extragenic regions are the key elements involved. As all extragenic spaces are putative regulatory regions, ExtraTrain covers all extragenic regions of available genomes and regulatory proteins from bacteria and archaea included in the UniProt database. Description ExtraTrain provides integrated and easily manageable information for 679816 extragenic regions and for the genes delimiting each of them. In addition ExtraTrain supplies a tool to explore extragenic regions, named Palinsight, oriented to detect and search palindromic patterns. This interactive visual tool is totally integrated in the database, allowing the search for regulatory signals in user defined sets of extragenic regions. The 26046 regulatory proteins included in ExtraTrain belong to the families AraC/XylS, ArsR, AsnC, Cold shock domain, CRP-FNR, DeoR, GntR, IclR, LacI, LuxR, LysR, MarR, MerR, NtrC/Fis, OmpR and TetR. The database follows the InterPro criteria to define these families. The information about regulators includes manually curated sets of references specifically associated to regulator entries. In order to achieve a sustainable and maintainable knowledge database ExtraTrain is a platform open to the contribution of knowledge by the scientific community providing a system for the incorporation of textual knowledge. Conclusion ExtraTrain is a new database for exploring Extragenic regions and Transcriptional information in bacteria and archaea. ExtraTrain database is available at . PMID:16539733

Spatiotemporal Patterns, Monitoring Network Design, and Environmental Justice of Air Pollution in the Phoenix Metropolitan Region: A Landscape Approach

NASA Astrophysics Data System (ADS)

Pope, Ronald L.

Air pollution is a serious problem in most urban areas around the world, which has a number of negative ecological and human health impacts. As a result, it's vitally important to detect and characterize air pollutants to protect the health of the urban environment and our citizens. An important early step in this process is ensuring that the air pollution monitoring network is properly designed to capture the patterns of pollution and that all social demographics in the urban population are represented. An important aspect in characterizing air pollution patterns is scale in space and time which, along with pattern and process relationships, is a key subject in the field of landscape ecology. Thus, using multiple landscape ecological methods, this dissertation research begins by characterizing and quantifying the multi-scalar patterns of ozone (O3) and particulate matter (PM10) in the Phoenix, Arizona, metropolitan region. Results showed that pollution patterns are scale-dependent, O3 is a regionally-scaled pollutant at longer temporal scales, and PM10 is a locally-scaled pollutant with patterns sensitive to season. Next, this dissertation examines the monitoring network within Maricopa County. Using a novel multiscale indicator-based approach, the adequacy of the network was quantified by integrating inputs from various academic and government stakeholders. Furthermore, deficiencies were spatially defined and recommendations were made on how to strengthen the design of the network. A sustainability ranking system also provided new insight into the strengths and weaknesses of the network. Lastly, the study addresses the question of whether distinct social groups were experiencing inequitable exposure to pollutants - a key issue of distributive environmental injustice. A novel interdisciplinary method using multi-scalar ambient pollution data and hierarchical multiple regression models revealed environmental inequities between air pollutants and race, ethnicity, age, and socioeconomic classes. The results indicate that changing the scale of the analysis can change the equitable relationship between pollution and demographics. The scientific findings of the scale-dependent relationships among air pollution patterns, network design, and population demographics, brought to light through this study, can help policymakers make informed decisions for protecting the human health and the urban environment in the Phoenix metropolitan region and beyond.

AERONET derived (BC) aerosol absorption

NASA Astrophysics Data System (ADS)

Kinne, S.

2015-12-01

AERONET is a ground-based sun-/sky-photometer network with good annual statistics at more than 400 sites worldwide. Inversion methods applied to these data define all relevant column aerosol optical properties and reveal even microphysical detail. The extracted data include estimates for aerosol size-distributions and for aerosol refractive indices at four different solar wavelengths. Hereby, the imaginary parts of the refractive indices define the aerosol column absorption. For regional and global averages and radiative impact assessment with off-line radiative transfer, these local data have been extended with distribution patterns offered by AeroCom modeling experiments. Annual and seasonal absorption distributions for total aerosol and estimates for component contributions (such as BC) are presented and associated direct forcing impacts are quantified.

Fine tuning of Rac1 and RhoA alters cuspal shapes by remolding the cellular geometry

PubMed Central

Li, Liwen; Tang, Qinghuang; Nakamura, Takashi; Suh, Jun-Gyo; Ohshima, Hayato; Jung, Han-Sung

2016-01-01

The anatomic and functional combinations of cusps and lophs (ridges) define the tooth shape of rodent molars, which distinguishes species. The species-specific cusp patterns result from the spatiotemporal induction of enamel knots (EKs), which require precisely controlled cellular behavior to control the epithelial invagination. Despite the well-defined roles of EK in cusp patterning, the determinants of the ultimate cuspal shapes and involvement of epithelial cellular geometry are unknown. Using two typical tooth patterns, the lophodont in gerbils and the bunodont in mice, we showed that the cuspal shape is determined by the dental epithelium at the cap stage, whereas the cellular geometry in the inner dental epithelium (IDE) is correlated with the cuspal shape. Intriguingly, fine tuning Rac1 and RhoA interconvert cuspal shapes between two species by remolding the cellular geometry. Either inhibition of Rac1 or ectopic expression of RhoA could region-distinctively change the columnar shape of IDE cells in gerbils to drive invagination to produce cusps. Conversely, RhoA reduction in mice inhibited invagination and developed lophs. Furthermore, we found that Rac1 and RhoA modulate the choices of cuspal shape by coordinating adhesion junctions, actin distribution, and fibronectin localization to drive IDE invagination. PMID:27892530

The comparative phylogeography of east coast estuarine fishes in formerly glaciated sites: Persistence versus recolonization in Cyprinodon variegatus ovinus and Fundulus heteroclitus macrolepidotus.

PubMed

Haney, Robert A; Dionne, Michelle; Puritz, Jon; Rand, David M

2009-01-01

Species distributions may be dramatically affected by climatic variability, such as occurred during Pleistocene glaciation. Populations of coastal organisms could have been affected directly by ice movement or through sea level change. Response could involve shifts in distribution southwards or persistence through the full range or in limited high-latitude refugia. Comparative studies of the response of ecologically similar species can provide a useful complement to those examining response across disparate species in defining what parameters influence persistence. Patterns of mitochondrial genetic variation in 2 estuarine fish subspecies from the Northwest Atlantic, Fundulus heteroclitus macrolepidotus and Cyprinodon variegatus ovinus, indicate that ecological similarity does not necessarily predict propensity for glacial persistence. Fundulus heteroclitus macrolepidotus is highly diverse in glaciated regions, with isolated populations whose origins predate the last glacial maximum and may have recently expanded it's range to the south from New England. However, within glaciated regions, signals of population growth and distributional shifts indicate a dynamic Pleistocene history for F. h. macrolepidotus, in contrast with recent studies involving microsatellites. A different pattern is found in C. v. ovinus, which is depauperate in formerly glaciated sites, with a clear signal of recent recolonization of glaciated regions from the south. Genetic differentiation in glaciated areas is consistent with isolation after glacial withdrawal. In C. v. ovinus, rapidly evolving microsatellite loci show a similar pattern to mitochondrial DNA but may be reaching equilibrium on small spatial scales. These contrasting patterns of variation illustrate how ecologically similar species can respond to large-scale environmental change in distinct ways.

Three chromosomal rearrangements promote genomic divergence between migratory and stationary ecotypes of Atlantic cod.

PubMed

Berg, Paul R; Star, Bastiaan; Pampoulie, Christophe; Sodeland, Marte; Barth, Julia M I; Knutsen, Halvor; Jakobsen, Kjetill S; Jentoft, Sissel

2016-03-17

Identification of genome-wide patterns of divergence provides insight on how genomes are influenced by selection and can reveal the potential for local adaptation in spatially structured populations. In Atlantic cod - historically a major marine resource - Northeast-Arctic- and Norwegian coastal cod are recognized by fundamental differences in migratory and non-migratory behavior, respectively. However, the genomic architecture underlying such behavioral ecotypes is unclear. Here, we have analyzed more than 8.000 polymorphic SNPs distributed throughout all 23 linkage groups and show that loci putatively under selection are localized within three distinct genomic regions, each of several megabases long, covering approximately 4% of the Atlantic cod genome. These regions likely represent genomic inversions. The frequency of these distinct regions differ markedly between the ecotypes, spawning in the vicinity of each other, which contrasts with the low level of divergence in the rest of the genome. The observed patterns strongly suggest that these chromosomal rearrangements are instrumental in local adaptation and separation of Atlantic cod populations, leaving footprints of large genomic regions under selection. Our findings demonstrate the power of using genomic information in further understanding the population dynamics and defining management units in one of the world's most economically important marine resources.

New Reasons to Preserve the Amazon Rainforest

NASA Astrophysics Data System (ADS)

Costa, M. H.

2014-12-01

Historically, preservation of the rainforest was justified in terms of conservation of biodiversity, protection of indigenous people habitats and maintenance of carbon stocks. Most of these arguments are based on the direct effect of rainforest removal, and ignore second order effects of the presence of the rainforest, such as modulation of regional climate patterns. The rainforest helps define the regional climate of the region, in particular the regional temperature and precipitation patterns. Of course, any activity that depends on the local climate may be affected by changes in the rainforest. Recent evidence in the literature presented enough arguments to believe that the widespread removal of the rainforest will have economic consequences at least in agriculture output and hydroelectric power generation. Economic impacts may affect not only the agriculture and energy sectors, but also several other economic activities that are related to climate. As a country, we are counting with the climate of Amazonia as fixed, but if the present climate needs the presence of the rainforest, we need to quantify the economic value of the climate regulation service provided by the rainforest. Important questions to be answered: How much of the rainforest is needed to conserve the present climate? Where it should stand for best climate regulation? Answer to these questions may affect Brazil´s large-scale policy on land use.

Structural brain connectivity and cognitive ability differences: A multivariate distance matrix regression analysis.

PubMed

Ponsoda, Vicente; Martínez, Kenia; Pineda-Pardo, José A; Abad, Francisco J; Olea, Julio; Román, Francisco J; Barbey, Aron K; Colom, Roberto

2017-02-01

Neuroimaging research involves analyses of huge amounts of biological data that might or might not be related with cognition. This relationship is usually approached using univariate methods, and, therefore, correction methods are mandatory for reducing false positives. Nevertheless, the probability of false negatives is also increased. Multivariate frameworks have been proposed for helping to alleviate this balance. Here we apply multivariate distance matrix regression for the simultaneous analysis of biological and cognitive data, namely, structural connections among 82 brain regions and several latent factors estimating cognitive performance. We tested whether cognitive differences predict distances among individuals regarding their connectivity pattern. Beginning with 3,321 connections among regions, the 36 edges better predicted by the individuals' cognitive scores were selected. Cognitive scores were related to connectivity distances in both the full (3,321) and reduced (36) connectivity patterns. The selected edges connect regions distributed across the entire brain and the network defined by these edges supports high-order cognitive processes such as (a) (fluid) executive control, (b) (crystallized) recognition, learning, and language processing, and (c) visuospatial processing. This multivariate study suggests that one widespread, but limited number, of regions in the human brain, supports high-level cognitive ability differences. Hum Brain Mapp 38:803-816, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Information processing architecture of functionally defined clusters in the macaque cortex.

PubMed

Shen, Kelly; Bezgin, Gleb; Hutchison, R Matthew; Gati, Joseph S; Menon, Ravi S; Everling, Stefan; McIntosh, Anthony R

2012-11-28

Computational and empirical neuroimaging studies have suggested that the anatomical connections between brain regions primarily constrain their functional interactions. Given that the large-scale organization of functional networks is determined by the temporal relationships between brain regions, the structural limitations may extend to the global characteristics of functional networks. Here, we explored the extent to which the functional network community structure is determined by the underlying anatomical architecture. We directly compared macaque (Macaca fascicularis) functional connectivity (FC) assessed using spontaneous blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI) to directed anatomical connectivity derived from macaque axonal tract tracing studies. Consistent with previous reports, FC increased with increasing strength of anatomical connection, and FC was also present between regions that had no direct anatomical connection. We observed moderate similarity between the FC of each region and its anatomical connectivity. Notably, anatomical connectivity patterns, as described by structural motifs, were different within and across functional modules: partitioning of the functional network was supported by dense bidirectional anatomical connections within clusters and unidirectional connections between clusters. Together, our data directly demonstrate that the FC patterns observed in resting-state BOLD-fMRI are dictated by the underlying neuroanatomical architecture. Importantly, we show how this architecture contributes to the global organizational principles of both functional specialization and integration.

Two-photon NADH imaging exposes boundaries of oxygen diffusion in cortical vascular supply regions

PubMed Central

Kasischke, Karl A; Lambert, Elton M; Panepento, Ben; Sun, Anita; Gelbard, Harris A; Burgess, Robert W; Foster, Thomas H; Nedergaard, Maiken

2011-01-01

Oxygen transport imposes a possible constraint on the brain's ability to sustain variable metabolic demands, but oxygen diffusion in the cerebral cortex has not yet been observed directly. We show that concurrent two-photon fluorescence imaging of endogenous nicotinamide adenine dinucleotide (NADH) and the cortical microcirculation exposes well-defined boundaries of tissue oxygen diffusion in the mouse cortex. The NADH fluorescence increases rapidly over a narrow, very low pO2 range with a p50 of 3.4±0.6 mm Hg, thereby establishing a nearly binary reporter of significant, metabolically limiting hypoxia. The transient cortical tissue boundaries of NADH fluorescence exhibit remarkably delineated geometrical patterns, which define the limits of tissue oxygen diffusion from the cortical microcirculation and bear a striking resemblance to the ideal Krogh tissue cylinder. The visualization of microvessels and their regional contribution to oxygen delivery establishes penetrating arterioles as major oxygen sources in addition to the capillary network and confirms the existence of cortical oxygen fields with steep microregional oxygen gradients. Thus, two-photon NADH imaging can be applied to expose vascular supply regions and to localize functionally relevant microregional cortical hypoxia with micrometer spatial resolution. PMID:20859293

Two-photon NADH imaging exposes boundaries of oxygen diffusion in cortical vascular supply regions.

PubMed

Kasischke, Karl A; Lambert, Elton M; Panepento, Ben; Sun, Anita; Gelbard, Harris A; Burgess, Robert W; Foster, Thomas H; Nedergaard, Maiken

2011-01-01

Oxygen transport imposes a possible constraint on the brain's ability to sustain variable metabolic demands, but oxygen diffusion in the cerebral cortex has not yet been observed directly. We show that concurrent two-photon fluorescence imaging of endogenous nicotinamide adenine dinucleotide (NADH) and the cortical microcirculation exposes well-defined boundaries of tissue oxygen diffusion in the mouse cortex. The NADH fluorescence increases rapidly over a narrow, very low pO(2) range with a p(50) of 3.4 ± 0.6 mm Hg, thereby establishing a nearly binary reporter of significant, metabolically limiting hypoxia. The transient cortical tissue boundaries of NADH fluorescence exhibit remarkably delineated geometrical patterns, which define the limits of tissue oxygen diffusion from the cortical microcirculation and bear a striking resemblance to the ideal Krogh tissue cylinder. The visualization of microvessels and their regional contribution to oxygen delivery establishes penetrating arterioles as major oxygen sources in addition to the capillary network and confirms the existence of cortical oxygen fields with steep microregional oxygen gradients. Thus, two-photon NADH imaging can be applied to expose vascular supply regions and to localize functionally relevant microregional cortical hypoxia with micrometer spatial resolution.

Synthesis of regional crust and upper-mantle structure from seismic and gravity data

NASA Technical Reports Server (NTRS)

Alexander, S. S.; Lavin, P. M.

1979-01-01

Available seismic and ground based gravity data are combined to infer the three dimensional crust and upper mantle structure in selected regions. This synthesis and interpretation proceeds from large-scale average models suitable for early comparison with high-altitude satellite potential field data to more detailed delineation of structural boundaries and other variations that may be significant in natural resource assessment. Seismic and ground based gravity data are the primary focal point, but other relevant information (e.g. magnetic field, heat flow, Landsat imagery, geodetic leveling, and natural resources maps) is used to constrain the structure inferred and to assist in defining structural domains and boundaries. The seismic data consists of regional refraction lines, limited reflection coverage, surface wave dispersion, teleseismic P and S wave delay times, anelastic absorption, and regional seismicity patterns. The gravity data base consists of available point gravity determinations for the areas considered.

A comparison of regional flood frequency analysis approaches in a simulation framework

NASA Astrophysics Data System (ADS)

Ganora, D.; Laio, F.

2016-07-01

Regional frequency analysis (RFA) is a well-established methodology to provide an estimate of the flood frequency curve at ungauged (or scarcely gauged) sites. Different RFA approaches exist, depending on the way the information is transferred to the site of interest, but it is not clear in the literature if a specific method systematically outperforms the others. The aim of this study is to provide a framework wherein carrying out the intercomparison by building up a virtual environment based on synthetically generated data. The considered regional approaches include: (i) a unique regional curve for the whole region; (ii) a multiple-region model where homogeneous subregions are determined through cluster analysis; (iii) a Region-of-Influence model which defines a homogeneous subregion for each site; (iv) a spatially smooth estimation procedure where the parameters of the regional model vary continuously along the space. Virtual environments are generated considering different patterns of heterogeneity, including step change and smooth variations. If the region is heterogeneous, with the parent distribution changing continuously within the region, the spatially smooth regional approach outperforms the others, with overall errors 10-50% lower than the other methods. In the case of a step-change, the spatially smooth and clustering procedures perform similarly if the heterogeneity is moderate, while clustering procedures work better when the step-change is severe. To extend our findings, an extensive sensitivity analysis has been performed to investigate the effect of sample length, number of virtual stations, return period of the predicted quantile, variability of the scale parameter of the parent distribution, number of predictor variables and different parent distribution. Overall, the spatially smooth approach appears as the most robust approach as its performances are more stable across different patterns of heterogeneity, especially when short records are considered.

Determining coding CpG islands by identifying regions significant for pattern statistics on Markov chains.

PubMed

Singer, Meromit; Engström, Alexander; Schönhuth, Alexander; Pachter, Lior

2011-09-23

Recent experimental and computational work confirms that CpGs can be unmethylated inside coding exons, thereby showing that codons may be subjected to both genomic and epigenomic constraint. It is therefore of interest to identify coding CpG islands (CCGIs) that are regions inside exons enriched for CpGs. The difficulty in identifying such islands is that coding exons exhibit sequence biases determined by codon usage and constraints that must be taken into account. We present a method for finding CCGIs that showcases a novel approach we have developed for identifying regions of interest that are significant (with respect to a Markov chain) for the counts of any pattern. Our method begins with the exact computation of tail probabilities for the number of CpGs in all regions contained in coding exons, and then applies a greedy algorithm for selecting islands from among the regions. We show that the greedy algorithm provably optimizes a biologically motivated criterion for selecting islands while controlling the false discovery rate. We applied this approach to the human genome (hg18) and annotated CpG islands in coding exons. The statistical criterion we apply to evaluating islands reduces the number of false positives in existing annotations, while our approach to defining islands reveals significant numbers of undiscovered CCGIs in coding exons. Many of these appear to be examples of functional epigenetic specialization in coding exons.

Seismo-Tectonics of the 2014 Chiang Rai, Thailand, Earthquake Sequence

NASA Astrophysics Data System (ADS)

Furlong, K. P.; Pananont, P.; Herman, M. W.; Waldhauser, F.; Pornsopin, P.; Warnitchai, P.; Kosuwan, S.

2016-12-01

On 5 May 2014, a Mw 6.2 strike-slip earthquake struck in the Mae Lao region of Chiang Rai province in Thailand. This earthquake occurred in a region of known faults, but identified as relatively low earthquake hazard, and caused substantial damage and injuries. Detailed field reconnaissance and deployment of a dense, temporary seismometer network allowed details of the damage and its relationship to seismicity to be analyzed. The aftershock sequence associated with this mainshock occurs on two well-defined trends, reflecting the two potential fault planes in earthquake focal mechanisms for the mainshock and the majority of the aftershocks. The damage area was relatively large for an event of this magnitude, but primarily occurs within the primary rupture (aftershock) region or along regional rivers with soils susceptible to liquefaction of other ground failure. Stress modeling combined with the time-series and pattern of aftershock activity lead us to propose that the initial mainshock rupture continued slightly onto its conjugate faults near its northern termination, helping to trigger the distinct pattern of two discrete, conjugate trends of aftershock activity that mirror the kinematics of the mainshock fault mechanism. Although this earthquake occurred in a region of known faults, it cannot be directly linked to a previously mapped structure. This coupled with the substantial damage from the event indicates that there is potentially a higher earthquake hazard in northern and central Thailand than previously recognized.

Viral Determinants of Integration Site Preferences of Simian Immunodeficiency Virus-Based Vectors

PubMed Central

Monse, Hella; Laufs, Stephanie; Kuate, Seraphin; Zeller, W. Jens; Fruehauf, Stefan; Überla, Klaus

2006-01-01

Preferential integration into transcriptionally active regions of genomes has been observed for retroviral vectors based on gamma-retroviruses and lentiviruses. However, differences in the integration site preferences were detected, which might be explained by differences in viral components of the preintegration complexes. Viral determinants of integration site preferences have not been defined. Therefore, integration sites of simian immunodeficiency virus (SIV)-based vectors produced in the absence of accessory genes or lacking promoter and enhancer elements were compared. Similar integration patterns for the different SIV vectors indicate that vif, vpr, vpx, nef, env, and promoter or enhancer elements are not required for preferential integration of SIV into transcriptionally active regions of genomes. PMID:16873270

The Extended Pulsar Magnetosphere

NASA Technical Reports Server (NTRS)

Constantinos, Kalapotharakos; Demosthenes, Kazanas; Ioannis, Contopoulos

2012-01-01

We present the structure of the 3D ideal MHD pulsar magnetosphere to a radius ten times that of the light cylinder, a distance about an order of magnitude larger than any previous such numerical treatment. Its overall structure exhibits a stable, smooth, well-defined undulating current sheet which approaches the kinematic split monopole solution of Bogovalov 1999 only after a careful introduction of diffusivity even in the highest resolution simulations. It also exhibits an intriguing spiral region at the crossing of two zero charge surfaces on the current sheet, which shows a destabilizing behavior more prominent in higher resolution simulations. We discuss the possibility that this region is physically (and not numerically) unstable. Finally, we present the spiral pulsar antenna radiation pattern.

Mineral resources, geologic structure, and landform surveys

NASA Technical Reports Server (NTRS)

Lattman, L. H.

1973-01-01

The use of ERTS-1 imagery for mineral resources, geologic structure, and landform surveys is discussed. Four categories of ERTS imagery application are defined and explained. The types of information obtained by the various multispectral band scanners are analyzed. Samples of land use maps and tectoning and metallogenic models are developed. It is stated that the most striking features visible on ERTS imagery are regional lineaments, or linear patterns in the topography, which reflect major fracture zones extending upward from the basement of the earth.

Apple skin patterning is associated with differential expression of MYB10

PubMed Central

2011-01-01

Background Some apple (Malus × domestica Borkh.) varieties have attractive striping patterns, a quality attribute that is important for determining apple fruit market acceptance. Most apple cultivars (e.g. 'Royal Gala') produce fruit with a defined fruit pigment pattern, but in the case of 'Honeycrisp' apple, trees can produce fruits of two different kinds: striped and blushed. The causes of this phenomenon are unknown. Results Here we show that striped areas of 'Honeycrisp' and 'Royal Gala' are due to sectorial increases in anthocyanin concentration. Transcript levels of the major biosynthetic genes and MYB10, a transcription factor that upregulates apple anthocyanin production, correlated with increased anthocyanin concentration in stripes. However, nucleotide changes in the promoter and coding sequence of MYB10 do not correlate with skin pattern in 'Honeycrisp' and other cultivars differing in peel pigmentation patterns. A survey of methylation levels throughout the coding region of MYB10 and a 2.5 Kb region 5' of the ATG translation start site indicated that an area 900 bp long, starting 1400 bp upstream of the translation start site, is highly methylated. Cytosine methylation was present in all three contexts, with higher methylation levels observed for CHH and CHG (where H is A, C or T) than for CG. Comparisons of methylation levels of the MYB10 promoter in 'Honeycrisp' red and green stripes indicated that they correlate with peel phenotypes, with an enrichment of methylation observed in green stripes. Conclusions Differences in anthocyanin levels between red and green stripes can be explained by differential transcript accumulation of MYB10. Different levels of MYB10 transcript in red versus green stripes are inversely associated with methylation levels in the promoter region. Although observed methylation differences are modest, trends are consistent across years and differences are statistically significant. Methylation may be associated with the presence of a TRIM retrotransposon within the promoter region, but the presence of the TRIM element alone cannot explain the phenotypic variability observed in 'Honeycrisp'. We suggest that methylation in the MYB10 promoter is more variable in 'Honeycrisp' than in 'Royal Gala', leading to more variable color patterns in the peel of this cultivar. PMID:21599973

A multi-model ensemble view of winter heat flux dynamics and the dipole mode in the Mediterranean Sea

NASA Astrophysics Data System (ADS)

Liguori, Giovanni; Di Lorenzo, Emanuele; Cabos, William

2017-02-01

Changes in surface heat fluxes affect several climate processes controlling the Mediterranean climate. These include the winter formation of deep waters, which is the primary driver of the Mediterranean Sea overturning circulation. Previous studies that characterize the spatial and temporal variability of surface heat flux anomalies over the basin reveal the existence of two statistically dominant patterns of variability: a monopole of uniform sign and an east-west dipole of opposite signs. In this work, we use the 12 regional climate model ensemble from the EU-FP6 ENSEMBLES project to diagnose the large-scale atmospheric processes that control the variability of heat fluxes over the Mediterranean Sea from interannual to decadal timescales (here defined as timescales > 6 year). Our findings suggest that while the monopole structure captures variability in the winter-to-winter domain-average net heat flux, the dipole pattern tracks changes in the Mediterranean climate that are connected to the East Atlantic/Western Russia (EA/WR) atmospheric teleconnection pattern. Furthermore, while the monopole exhibits significant differences in the spatial structure across the multi-model ensemble, the dipole pattern is very robust and more clearly identifiable in the anomaly maps of individual years. A heat budget analysis of the dipole pattern reveals that changes in winds associated with the EA/WR pattern exert dominant control through both a direct effect on the latent heat flux (i.e., wind speed) and an indirect effect through specific humidity (e.g., wind advection). A simple reconstruction of the heat flux variability over the deep-water formation regions of the Gulf of Lion and the Aegean Sea reveals that the combination of the monopole and dipole time series explains over 90 % of the heat flux variance in these regions. Given the important role that surface heat flux anomalies play in deep-water formation and the regional climate, improving our knowledge on the dynamics controlling the leading modes of heat flux variability may enhance our predictability of the climate of the Mediterranean area.

Contour junctions defined by dynamic image deformations enhance perceptual transparency.

PubMed

Kawabe, Takahiro; Nishida, Shin'ya

2017-11-01

The majority of work on the perception of transparency has focused on static images with luminance-defined contour junctions, but recent work has shown that dynamic image sequences with dynamic image deformations also provide information about transparency. The present study demonstrates that when part of a static image is dynamically deformed, contour junctions at which deforming and nondeforming contours are connected facilitate the deformation-based perception of a transparent layer. We found that the impression of a transparent layer was stronger when a dynamically deforming area was adjacent to static nondeforming areas than when presented alone. When contour junctions were not formed at the dynamic-static boundaries, however, the impression of a transparent layer was not facilitated by the presence of static surrounding areas. The effect of the deformation-defined junctions was attenuated when the spatial pattern of luminance contrast at the junctions was inconsistent with the perceived transparency related to luminance contrast, while the effect did not change when the spatial luminance pattern was consistent with it. In addition, the results showed that contour completions across the junctions were required for the perception of a transparent layer. These results indicate that deformation-defined junctions that involve contour completion between deforming and nondeforming regions enhance the perception of a transparent layer, and that the deformation-based perceptual transparency can be promoted by the simultaneous presence of appropriately configured luminance and contrast-other features that can also by themselves produce the sensation of perceiving transparency.

Have Large Dams Altered Extreme Precipitation Patterns?

NASA Astrophysics Data System (ADS)

Hossain, Faisal; Jeyachandran, Indumathi; Pielke, Roger

2009-12-01

Dams and their impounded waters are among the most common civil infrastructures, with a long heritage of modern design and operations experience. In particular, large dams, defined by the International Commission on Large Dams (ICOLD) as having a height greater than 15 meters from the foundation and holding a reservoir volume of more than 3 million cubic meters, have the potential to vastly transform local climate, landscapes, regional economics, and urbanization patterns. In the United States alone, about 75,000 dams are capable of storing a volume of water equaling almost 1 year's mean runoff of the nation [Graf, 1999]. The World Commission on Dams (WCD) reports that at least 45,000 large dams have been built worldwide since the 1930s. These sheer numbers raise the question of the extent to which large dams and their impounded waters alter patterns that would have been pervasive had the dams not been built.

Exogenous attention enhances 2nd-order contrast sensitivity

PubMed Central

Barbot, Antoine; Landy, Michael S.; Carrasco, Marisa

2011-01-01

Natural scenes contain a rich variety of contours that the visual system extracts to segregrate the retinal image into perceptually coherent regions. Covert spatial attention helps extract contours by enhancing contrast sensitivity for 1st-order, luminance-defined patterns at attended locations, while reducing sensitivity at unattended locations, relative to neutral attention allocation. However, humans are also sensitive to 2nd-order patterns such as spatial variations of texture, which are predominant in natural scenes and cannot be detected by linear mechanisms. We assess whether and how exogenous attention—the involuntary and transient capture of spatial attention—affects the contrast sensitivity of channels sensitive to 2nd-order, texture-defined patterns. Using 2nd-order, texture-defined stimuli, we demonstrate that exogenous attention increases 2nd-order contrast sensitivity at the attended location, while decreasing it at unattended locations, relative to a neutral condition. By manipulating both 1st- and 2nd-order spatial frequency, we find that the effects of attention depend both on 2nd-order spatial frequency of the stimulus and the observer’s 2nd-order spatial resolution at the target location. At parafoveal locations, attention enhances 2nd-order contrast sensitivity to high, but not to low 2nd-order spatial frequencies; at peripheral locations attention also enhances sensitivity to low 2nd-order spatial frequencies. Control experiments rule out the possibility that these effects might be due to an increase in contrast sensitivity at the 1st-order stage of visual processing. Thus, exogenous attention affects 2nd-order contrast sensitivity at both attended and unattended locations. PMID:21356228

Local and regional effects of large scale atmospheric circulation patterns on winter wind power output in Western Europe

NASA Astrophysics Data System (ADS)

Zubiate, Laura; McDermott, Frank; Sweeney, Conor; O'Malley, Mark

2014-05-01

Recent studies (Brayshaw, 2009, Garcia-Bustamante, 2010, Garcia-Bustamante, 2013) have drawn attention to the sensitivity of wind speed distributions and likely wind energy power output in Western Europe to changes in low-frequency, large scale atmospheric circulation patterns such as the North Atlantic Oscillation (NAO). Wind speed variations and directional shifts as a function of the NAO state can be larger or smaller depending on the North Atlantic region that is considered. Wind speeds in Ireland and the UK for example are approximately 20 % higher during NAO + phases, and up to 30 % lower during NAO - phases relative to the long-term (30 year) climatological means. By contrast, in southern Europe, wind speeds are 15 % lower than average during NAO + phases and 15 % higher than average during NAO - phases. Crucially however, some regions such as Brittany in N.W. France have been identified in which there is negligible variability in wind speeds as a function of the NAO phase, as observed in the ERA-Interim 0.5 degree gridded reanalysis database. However, the magnitude of these effects on wind conditions is temporally and spatially non-stationary. As described by Comas-Bru and McDermott (2013) for temperature and precipitation, such non-stationarity is caused by the influence of two other patterns, the East Atlantic pattern, (EA), and the Scandinavian pattern, (SCA), which modulate the position of the NAO dipole. This phenomenon has also implications for wind speeds and directions, which has been assessed using the ERA-Interim reanalysis dataset and the indices obtained from the PC analysis of sea level pressure over the Atlantic region. In order to study the implications for power production, the interaction of the NAO and the other teleconnection patterns with local topography was also analysed, as well as how these interactions ultimately translate into wind power output. The objective is to have a better defined relationship between wind speed and power output at a local level and a tool that wind farm developers could use to inform site selection. A particular priority was to assess how the potential wind power outputs over a 25-30 year windfarm lifetime in less windy, but resource-stable regions, compare with those from windier but more variable sites.

Magnetic-film atom chip with 10 μm period lattices of microtraps for quantum information science with Rydberg atoms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leung, V. Y. F.; Complex Photonic Systems; Pijn, D. R. M.

2014-05-15

We describe the fabrication and construction of a setup for creating lattices of magnetic microtraps for ultracold atoms on an atom chip. The lattice is defined by lithographic patterning of a permanent magnetic film. Patterned magnetic-film atom chips enable a large variety of trapping geometries over a wide range of length scales. We demonstrate an atom chip with a lattice constant of 10 μm, suitable for experiments in quantum information science employing the interaction between atoms in highly excited Rydberg energy levels. The active trapping region contains lattice regions with square and hexagonal symmetry, with the two regions joined atmore » an interface. A structure of macroscopic wires, cutout of a silver foil, was mounted under the atom chip in order to load ultracold {sup 87}Rb atoms into the microtraps. We demonstrate loading of atoms into the square and hexagonal lattice sections simultaneously and show resolved imaging of individual lattice sites. Magnetic-film lattices on atom chips provide a versatile platform for experiments with ultracold atoms, in particular for quantum information science and quantum simulation.« less

Markers of oxidative damage to lipids, nucleic acids and proteins and antioxidant enzymes activities in Alzheimer's disease brain: A meta-analysis in human pathological specimens.

PubMed

Zabel, Matthew; Nackenoff, Alex; Kirsch, Wolff M; Harrison, Fiona E; Perry, George; Schrag, Matthew

2018-02-01

Oxidative stress and decreased cellular responsiveness to oxidative stress are thought to influence brain aging and Alzheimer's disease, but the specific patterns of oxidative damage and the underlying mechanism leading to this damage are not definitively known. The objective of this study was to define the pattern of changes in oxidative-stress related markers by brain region in human Alzheimer's disease and mild cognitive impairment brain tissue. Observational case-control studies were identified from systematic queries of PubMed, ISI Web of Science and Scopus databases and studies were evaluated with appropriate quality measures. The data was used to construct a region-by-region meta-analysis of malondialdehyde, 4-hydroxynonenal, protein carbonylation, 8-hydroxyguanine levels and superoxide dismutase, glutathione peroxidase, glutathione reductase and catalase activities. We also evaluated ascorbic acid, tocopherol, uric acid and glutathione levels. The analysis was complicated in several cases by publication bias and/or outlier data. We found that malondialdehyde levels were slightly increased in the temporal and occipital lobes and hippocampus, but this analysis was significantly impacted by publication bias. 4-hydroxynonenal levels were unchanged in every brain region. There was no change in 8-hydroxyguanine level in any brain region and protein carbonylation levels were unchanged except for a slight increase in the occipital lobe. Superoxide dismutase, glutathione peroxidase and reductase and catalase activities were not decreased in any brain region. There was limited data reporting non-enzymatic antioxidant levels in Alzheimer's disease brain, although glutathione and tocopherol levels appear to be unchanged. Minimal quantitative data is available from brain tissue from patients with mild cognitive impairment. While there is modest evidence supporting minor regional changes in markers of oxidative damage, this analysis fails to identify a consistent pattern of pro-oxidative changes and accumulation of oxidative damage in bulk tissue analysis in the setting of Alzheimer's disease, as has been widely reported. Copyright © 2017 Elsevier Inc. All rights reserved.

High-Density SNP Genotyping to Define β-Globin Locus Haplotypes

PubMed Central

Liu, Li; Muralidhar, Shalini; Singh, Manisha; Sylvan, Caprice; Kalra, Inderdeep S.; Quinn, Charles T.; Onyekwere, Onyinye C.; Pace, Betty S.

2014-01-01

Five major β-globin locus haplotypes have been established in individuals with sickle cell disease (SCD) from the Benin, Bantu, Senegal, Cameroon, and Arab-Indian populations. Historically, β-haplotypes were established using restriction fragment length polymorphism (RFLP) analysis across the β-locus, which consists of five functional β-like globin genes located on chromosome 11. Previous attempts to correlate these haplotypes as robust predictors of clinical phenotypes observed in SCD have not been successful. We speculate that the coverage and distribution of the RFLP sites located proximal to or within the globin genes are not sufficiently dense to accurately reflect the complexity of this region. To test our hypothesis, we performed RFLP analysis and high-density single nucleotide polymorphism (SNP) genotyping across the β-locus using DNA samples from either healthy African Americans with normal hemoglobin A (HbAA) or individuals with homozygous SS (HbSS) disease. Using the genotyping data from 88 SNPs and Haploview analysis, we generated a greater number of haplotypes than that observed with RFLP analysis alone. Furthermore, a unique pattern of long-range linkage disequilibrium between the locus control region and the β-like globin genes was observed in the HbSS group. Interestingly, we observed multiple SNPs within the HindIII restriction site located in the Gγ-globin intervening sequence II which produced the same RFLP pattern. These findings illustrated the inability of RFLP analysis to decipher the complexity of sequence variations that impacts genomic structure in this region. Our data suggest that high density SNP mapping may be required to accurately define β-haplotypes that correlate with the different clinical phenotypes observed in SCD. PMID:18829352

The endemic Patagonian vespertilionid assemblage is a depauperate ecomorphological vicariant of species-rich neotropical assemblages

PubMed Central

Giannini, Norberto P.

2017-01-01

Abstract Vespertilionidae is the most diverse chiropteran family, and its diversity is concentrated in warm regions of the World; however, due to physiological and behavioral adaptations, these bats also dominate bat faunas in temperate regions. Here we performed a comparative study of vespertilionid assemblages from two broad regions of the New World, the cold and harsh Patagonia, versus the remaining temperate-to-subtropical, extra-Patagonian eco-regions of the South American Southern Cone. We took an ecomorphological approach and analyzed the craniodental morphological structure of these assemblages within a phylogenetic framework. We measured 17 craniodental linear variables from 447 specimens of 22 currently recognized vespertilionid species of the study regions. We performed a multivariate analysis to define the morphofunctional space, and calculated the pattern and degree of species packing for each assemblage. We assessed the importance of phylogeny and biogeography, and their impact on depauperate (Patagonian) versus rich (extra-Patagonian) vespertilionid assemblages as determinants of morphospace structuring. We implemented a sensitivity analysis associated to small samples of rare species. The morphological patterns were determined chiefly by the evolutionary history of the family. The Patagonian assemblage can be described as a structurally similar but comparatively depauperate ecomorphological version of those assemblages from neighboring extra-Patagonian eco-regions. The Patagonian assemblage seems to have formed by successively adding populations from Northern regions that eventually speciated in the region, leaving corresponding sisters (vicariants) in extra-Patagonian eco-regions that continued to be characteristically richer. Despite being structurally akin, degree of species packing in Patagonia was comparatively very low, which may reflect the effect of limited dispersal success into a harsh region for bat survival. PMID:29492009

Seasonal Diversity Patterns of a Coastal Synechococcus Population

NASA Astrophysics Data System (ADS)

Hunter-Cevera, K. R.; Sosik, H. M.; Neubert, M.; Hammar, K.; Post, A.

2016-02-01

Understanding how environmental and ecological factors determine phytoplankton species abundances requires knowledge of the diversity present within a population. For the important primary producer Synechococcus, clades demonstrate differences in temperature tolerance, light acclimation, grazer palatability, and more. Marine Synechococcus populations are often composed of more than one clade, and overall population dynamics will be governed by the types of cells present and by their individual physiological capabilities. We investigate the diversity of the Synechococcus assemblage at the Martha's Vineyard Coastal Observatory with high-throughput sequencing of the V6 hypervariable region of the 16S rRNA gene. Small nucleotide differences within this region allow for resolution of distinct phylotypes that can have a direct correspondence to the well-defined Synechococcus clades. From a three-year time series, we find that the Synechococcus population is dominated by 5 distinct phylotypes, and that each type exhibits a repeatable, seasonal pattern in relative abundance. We use compositional data analysis techniques to investigate the relationships between these patterns and environmental factors. We further interpret these patterns in the context of Synechococcus population dynamics assessed by automated, submersible flow cytometry (FlowCytobot). Observed diel changes in cell size distributions, coupled with a validated matrix population model, provide estimates of in situ population division rates. We find strong evidence that the main seasonal diversity patterns are governed by temperature, but that biological loss agents likely shape the diversity structure for certain times of year. For some phylotypes, relative abundance patterns are also related to light and nutrients. The composition of Synechococcus over the annual cycle appears to directly affect seasonal features of cell abundance patterns, such as the spring bloom.

Patterns of differences in brain morphology in humans as compared to extant apes.

PubMed

Aldridge, Kristina

2011-01-01

Although human evolution is characterized by a vast increase in brain size, it is not clear whether or not certain regions of the brain are enlarged disproportionately in humans, or how this enlargement relates to differences in overall neural morphology. The aim of this study is to determine whether or not there are specific suites of features that distinguish the morphology of the human brain from that of apes. The study sample consists of whole brain, in vivo magnetic resonance images (MRIs) of anatomically modern humans (Homo sapiens sapiens) and five ape species (gibbons, orangutans, gorillas, chimpanzees, bonobos). Twenty-nine 3D landmarks, including surface and internal features of the brain were located on 3D MRI reconstructions of each individual using MEASURE software. Landmark coordinate data were scaled for differences in size and analyzed using Euclidean Distance Matrix Analysis (EDMA) to statistically compare the brains of each non-human ape species to the human sample. Results of analyses show both a pattern of brain morphology that is consistently different between all apes and humans, as well as patterns that differ among species. Further, both the consistent and species-specific patterns include cortical and subcortical features. The pattern that remains consistent across species indicates a morphological reorganization of 1) relationships between cortical and subcortical frontal structures, 2) expansion of the temporal lobe and location of the amygdala, and 3) expansion of the anterior parietal region. Additionally, results demonstrate that, although there is a pattern of morphology that uniquely defines the human brain, there are also patterns that uniquely differentiate human morphology from the morphology of each non-human ape species, indicating that reorganization of neural morphology occurred at the evolutionary divergence of each of these groups. Copyright © 2010 Elsevier Ltd. All rights reserved.

Patterns of differences in brain morphology in humans as compared to extant apes

PubMed Central

Aldridge, Kristina

2010-01-01

Although human evolution is characterized by a vast increase in brain size, it is not clear whether or not certain regions of the brain are enlarged disproportionately in humans, or how this enlargement relates to differences in overall neural morphology. The aim of this study is to determine whether or not there are specific suites of features that distinguish the morphology of the human brain from that of apes. The study sample consists of whole brain, in vivo magnetic resonance images (MRIs) of anatomically modern humans (Homo sapiens sapiens) and five ape species (gibbons, orangutans, gorillas, chimpanzees, bonobos). Twenty-nine 3D landmarks, including surface and internal features of the brain were located on 3D MRI reconstructions of each individual using MEASURE software. Landmark coordinate data were scaled for differences in size and analyzed using Euclidean Distance Matrix Analysis (EDMA) to statistically compare the brains of each non-human ape species to the human sample. Results of analyses show both a pattern of brain morphology that is consistently different between all apes and humans, as well as patterns that differ among species. Further, both the consistent and species-specific patterns include cortical and subcortical features. The pattern that remains consistent across species indicates a morphological reorganization of 1) relationships between cortical and subcortical frontal structures, 2) expansion of the temporal lobe and location of the amygdala, and 3) expansion of the anterior parietal region. Additionally, results demonstrate that, although there is a pattern of morphology that uniquely defines the human brain, there are also patterns that uniquely differentiate human morphology from the morphology of each non-human ape species, indicating that reorganization of neural morphology occurred at the evolutionary divergence of each of these groups. PMID:21056456

Geographic patterns of ground-dwelling arthropods across an ecoregional transition in the north American Southwest

USGS Publications Warehouse

Lightfoot, D.C.; Brantley, S.L.; Allen, Craig D.

2008-01-01

We examined the biogeographic patterns of ground-dwelling arthropod communities across a heterogeneous semiarid region of the Southern Rio Grande Rift Valley of New Mexico. Our 3 sites included portions of 5 ecoregions, with the middle site a transition area where all ecoregions converged. We addressed the following 3 questions: (1) Do the species assemblage patterns for ground arthropods across habitats and sites conform to recognized ecoregions? (2) Are arthropod assemblages in distinct vegetation-defined habitats within an ecoregion more similar to each other or to assemblages in similar vegetation-defined habitats in other ecoregions? (3) Is there a detectable edge effect with increased arthropod diversity in the area of converging ecoregions? We encountered 442 target arthropod species from pitfall traps operating continuously for 7 years over a series of different habitats at each of the 3 sites. We examined geographic distributions of spider and cricket/grasshopper species in detail, and they showed affinities for different ecoregions, respectively. Each habitat within a study site supported a unique overall arthropod assemblage; nevertheless, different habitats at the same site were more similar to each other than they were to similar habitats at other sites. Overall arthropod species richness was greatest in the area where all 5 ecoregions converged. Arthropod species and their geographic distributions are poorly known relative to vascular plants and vertebrate animals. Findings from this research indicate that ecoregional classification is a useful tool for understanding biogeographic patterns among arthropods.

Disturbance of DNA methylation patterns in the early phase of hepatocarcinogenesis induced by a choline-deficient L-amino acid-defined diet in rats.

PubMed

Shimizu, Kyoko; Onishi, Mariko; Sugata, Eriko; Sokuza, Yui; Mori, Chiharu; Nishikawa, Tomoki; Honoki, Kanya; Tsujiuchi, Toshifumi

2007-09-01

The authors investigated the DNA methylation patterns of the E-cadherin, Connexin 26 (Cx26), Rassf1a and c-fos genes in the early phase of rat hepatocarcinogenesis induced by a choline-deficient L-amino acid-defined (CDAA) diet. Six-week-old F344 male rats were continuously fed with the CDAA diet, and three animals were then killed at each of 4 and 8 days and 3 weeks. Genomic DNA was extracted from livers for assessment of methylation status in the 5' upstream regions of E-cadherin, Cx26, Rassf1a and c-fos genes by bisulfite sequencing, compared with normal livers. The livers of rats fed the CDAA diet for 4 and 8 days and 3 weeks were methylated in E-cadherin, Cx26 and Rassf1a genes, while normal livers were all unmethylated. In contrast, normal livers were highly methylated in c-fos gene. Although the livers at 4 days were weakly methylated, those at 8 days and 3 weeks were markedly unmethylated. Methylation patterns of CpG sites in E-cadherin, Cx26 and Rassf1a were sparse and the methylation was not associated with gene repression. These results indicate that gene-specific DNA methylation patterns were found in livers of rats after short-term feeding of the CDAA diet, suggesting gene-specific hypermethylation might be involved in the early phase of rat hepatocarcinogenesis induced by the CDAA diet.

Statistical-mechanical analysis of self-organization and pattern formation during the development of visual maps

NASA Astrophysics Data System (ADS)

Obermayer, K.; Blasdel, G. G.; Schulten, K.

1992-05-01

We report a detailed analytical and numerical model study of pattern formation during the development of visual maps, namely, the formation of topographic maps and orientation and ocular dominance columns in the striate cortex. Pattern formation is described by a stimulus-driven Markovian process, the self-organizing feature map. This algorithm generates topologically correct maps between a space of (visual) input signals and an array of formal ``neurons,'' which in our model represents the cortex. We define order parameters that are a function of the set of visual stimuli an animal perceives, and we demonstrate that the formation of orientation and ocular dominance columns is the result of a global instability of the retinoptic projection above a critical value of these order parameters. We characterize the spatial structure of the emerging patterns by power spectra, correlation functions, and Gabor transforms, and we compare model predictions with experimental data obtained from the striate cortex of the macaque monkey with optical imaging. Above the critical value of the order parameters the model predicts a lateral segregation of the striate cortex into (i) binocular regions with linear changes in orientation preference, where iso-orientation slabs run perpendicular to the ocular dominance bands, and (ii) monocular regions with low orientation specificity, which contain the singularities of the orientation map. Some of these predictions have already been verified by experiments.

Patient classification as an outlier detection problem: An application of the One-Class Support Vector Machine

PubMed Central

Mourão-Miranda, Janaina; Hardoon, David R.; Hahn, Tim; Marquand, Andre F.; Williams, Steve C.R.; Shawe-Taylor, John; Brammer, Michael

2011-01-01

Pattern recognition approaches, such as the Support Vector Machine (SVM), have been successfully used to classify groups of individuals based on their patterns of brain activity or structure. However these approaches focus on finding group differences and are not applicable to situations where one is interested in accessing deviations from a specific class or population. In the present work we propose an application of the one-class SVM (OC-SVM) to investigate if patterns of fMRI response to sad facial expressions in depressed patients would be classified as outliers in relation to patterns of healthy control subjects. We defined features based on whole brain voxels and anatomical regions. In both cases we found a significant correlation between the OC-SVM predictions and the patients' Hamilton Rating Scale for Depression (HRSD), i.e. the more depressed the patients were the more of an outlier they were. In addition the OC-SVM split the patient groups into two subgroups whose membership was associated with future response to treatment. When applied to region-based features the OC-SVM classified 52% of patients as outliers. However among the patients classified as outliers 70% did not respond to treatment and among those classified as non-outliers 89% responded to treatment. In addition 89% of the healthy controls were classified as non-outliers. PMID:21723950

Pan-Continental Droughts in North America over the Last Millennium

NASA Technical Reports Server (NTRS)

Cook, Benjamin I.; Smerdon, Jason E.; Seager, Richard; Cook, Edward R.

2014-01-01

Regional droughts are common in North America, but pan-continental droughts extending across multiple regions, including the 2012 event, are rare relative to single-region events. Here, the tree-ring-derived North American Drought Atlas is used to investigate drought variability in four regions over the last millennium, focusing on pan-continental droughts. During the Medieval Climate Anomaly (MCA), the central plains (CP), Southwest (SW), and Southeast (SE) regions experienced drier conditions and increased occurrence of droughts and the Northwest (NW) experienced several extended pluvials. Enhanced MCA aridity in the SW and CP manifested as multidecadal megadroughts. Notably, megadroughts in these regions differed in their timing and persistence, suggesting that they represent regional events influenced by local dynamics rather than a unified, continental-scale phenomena. There is no trend in pan-continental drought occurrence, defined as synchronous droughts in three or more regions. SW, CP, and SE (SW+CP+SE) droughts are the most common, occurring in 12 percent of all years and peaking in prevalence during the twelfth and thirteenth centuries; patterns involving three other regions occur in about 8 percent of years. Positive values of the Southern Oscillation index (La Nina conditions) are linked to SW, CP, and SE (SW+CP+SE) droughts and SW, CP, and NW (SW+CP+NW) droughts, whereas CP, NW, and SE (CP+NW+SE) droughts are associated with positive values of the Pacific decadal oscillation and Atlantic multidecadal oscillation. While relatively rare, pan-continental droughts are present in the paleo record and are linked to defined modes of climate variability, implying the potential for seasonal predictability. Assuming stable drought teleconnections, these events will remain an important feature of future North American hydroclimate, possibly increasing in their severity in step with other expected hydroclimate responses to increased greenhouse gas forcing.

Brief review of the chicken Major Histocompatibility Complex: the genes, their distribution on chromosome 16, and their contributions to disease resistance

PubMed Central

Miller, Marcia M.; Taylor, Robert L.

2016-01-01

Nearly all genes presently mapped to chicken chromosome 16 (GGA 16) have either a demonstrated role in immune responses or are considered to serve in immunity by reason of sequence homology with immune system genes defined in other species. The genes are best described in regional units. Among these, the best known is the polymorphic major histocompatibility complex-B (MHC-B) region containing genes for classical peptide antigen presentation. Nearby MHC-B is a small region containing two CD1 genes, which encode molecules known to bind lipid antigens and which will likely be found in chickens to present lipids to specialized T cells, as occurs with CD1 molecules in other species. Another region is the MHC-Y region, separated from MHC-B by an intervening region of tandem repeats. Like MHC-B, MHC-Y is polymorphic. It contains specialized class I and class II genes and c-type lectin-like genes. Yet another region, separated from MHC-Y by the single nucleolar organizing region (NOR) in the chicken genome, contains olfactory receptor genes and scavenger receptor genes, which are also thought to contribute to immunity. The structure, distribution, linkages and patterns of polymorphism in these regions, suggest GGA 16 evolves as a microchromosome devoted to immune defense. Many GGA 16 genes are polymorphic and polygenic. At the moment most disease associations are at the haplotype level. Roles of individual MHC genes in disease resistance are documented in only a very few instances. Provided suitable experimental stocks persist, the availability of increasingly detailed maps of GGA 16 genes combined with new means for detecting genetic variability will lead to investigations defining the contributions of individual loci and more applications for immunogenetics in breeding healthy poultry. PMID:26740135

Dynamic Trial-by-Trial Recoding of Task-Set Representations in the Frontoparietal Cortex Mediates Behavioral Flexibility

PubMed Central

Qiao, Lei; Zhang, Lijie

2017-01-01

Cognitive flexibility forms the core of the extraordinary ability of humans to adapt, but the precise neural mechanisms underlying our ability to nimbly shift between task sets remain poorly understood. Recent functional magnetic resonance imaging (fMRI) studies employing multivoxel pattern analysis (MVPA) have shown that a currently relevant task set can be decoded from activity patterns in the frontoparietal cortex, but whether these regions support the dynamic transformation of task sets from trial to trial is not clear. Here, we combined a cued task-switching protocol with human (both sexes) fMRI, and harnessed representational similarity analysis (RSA) to facilitate a novel assessment of trial-by-trial changes in neural task-set representations. We first used MVPA to define task-sensitive frontoparietal and visual regions and found that neural task-set representations on switch trials are less stably encoded than on repeat trials. We then exploited RSA to show that the neural representational pattern dissimilarity across consecutive trials is greater for switch trials than for repeat trials, and that the degree of this pattern dissimilarity predicts behavior. Moreover, the overall neural pattern of representational dissimilarities followed from the assumption that repeating sets, compared with switching sets, results in stronger neural task representations. Finally, when moving from cue to target phase within a trial, pattern dissimilarities tracked the transformation from previous-trial task representations to the currently relevant set. These results provide neural evidence for the longstanding assumptions of an effortful task-set reconfiguration process hampered by task-set inertia, and they demonstrate that frontoparietal and stimulus processing regions support “dynamic adaptive coding,” flexibly representing changing task sets in a trial-by-trial fashion. SIGNIFICANCE STATEMENT Humans can fluently switch between different tasks, reflecting an ability to dynamically configure “task sets,” rule representations that link stimuli to appropriate responses. Recent studies show that neural signals in frontal and parietal brain regions can tell us which of two tasks a person is currently performing. However, it is not known whether these regions are also involved in dynamically reconfiguring task-set representations when switching between tasks. Here we measured human brain activity during task switching and tracked the similarity of neural task-set representations from trial to trial. We show that frontal and parietal brain regions flexibly recode changing task sets in a trial-by-trial fashion, and that task-set similarity over consecutive trials predicts behavior. PMID:28972126

Estimation of design floods in ungauged catchments using a regional index flood method. A case study of Lake Victoria Basin in Kenya

NASA Astrophysics Data System (ADS)

Nobert, Joel; Mugo, Margaret; Gadain, Hussein

Reliable estimation of flood magnitudes corresponding to required return periods, vital for structural design purposes, is impacted by lack of hydrological data in the study area of Lake Victoria Basin in Kenya. Use of regional information, derived from data at gauged sites and regionalized for use at any location within a homogenous region, would improve the reliability of the design flood estimation. Therefore, the regional index flood method has been applied. Based on data from 14 gauged sites, a delineation of the basin into two homogenous regions was achieved using elevation variation (90-m DEM), spatial annual rainfall pattern and Principal Component Analysis of seasonal rainfall patterns (from 94 rainfall stations). At site annual maximum series were modelled using the Log normal (LN) (3P), Log Logistic Distribution (LLG), Generalized Extreme Value (GEV) and Log Pearson Type 3 (LP3) distributions. The parameters of the distributions were estimated using the method of probability weighted moments. Goodness of fit tests were applied and the GEV was identified as the most appropriate model for each site. Based on the GEV model, flood quantiles were estimated and regional frequency curves derived from the averaged at site growth curves. Using the least squares regression method, relationships were developed between the index flood, which is defined as the Mean Annual Flood (MAF) and catchment characteristics. The relationships indicated area, mean annual rainfall and altitude were the three significant variables that greatly influence the index flood. Thereafter, estimates of flood magnitudes in ungauged catchments within a homogenous region were estimated from the derived equations for index flood and quantiles from the regional curves. These estimates will improve flood risk estimation and to support water management and engineering decisions and actions.

Urban growth patterns in major Southeast Asian cities: Toward exposure mapping and vulnerability assessment

NASA Astrophysics Data System (ADS)

Mandapaka, Pradeep; Kamarajugedda, Shankar A.; Lo, Edmond Y. M.

2017-04-01

Southeast Asia (SEA) is undergoing rapid urbanization, with urban population percentage increasing from 32% in 1990 to 48% in 2015. It is projected that by the year 2040, urban regions in SEA account for 60% of its total population. The region is home to 600 million people, with many densely populated cities, including megacities such as Jakarta, Bangkok, and Manila. The region has more than 20,000 islands, and many cities lie on coastal low-lands and floodplains. These geographical characteristics together with the increasing population, infrastructure growth, and changing climate makes the region highly vulnerable to natural hazards. This study assessed urban growth dynamics in major (defined as population exceeding 1 million) SEA cities using remotely sensed night-time lights (NTL) data. A recently proposed brightness gradient approach was applied on 21 years (1992-2012) of NTL annual composites to derive core-urban (CU) and peri-urban (PU) regions within each city. The study also assessed the sensitivity of above extracted urban categories to different NTL thresholds. The temporal trends in CU and PU regions were quantified, and compared with trends in socio-economic indicators. The spatial expansion of CU and PU regions were found to depend on geographical constraints and socio-economic factors. Quantification of urban growth spatial-temporal patterns, as conducted here contributes towards the understanding of exposure and vulnerability of people and infrastructures to natural hazards, as well as the evolving trends for assessment under projected urbanization conditions. This will underpin better risk assessment efforts for present and future planning.

Application of CPL with Interference Mapping Lithography to generate random contact reticle designs for the 65-nm node

NASA Astrophysics Data System (ADS)

Van Den Broeke, Douglas J.; Laidig, Thomas L.; Chen, J. Fung; Wampler, Kurt E.; Hsu, Stephen D.; Shi, Xuelong; Socha, Robert J.; Dusa, Mircea V.; Corcoran, Noel P.

2004-08-01

Imaging contact and via layers continues to be one of the major challenges to be overcome for 65nm node lithography. Initial results of using ASML MaskTools' CPL Technology to print contact arrays through pitch have demonstrated the potential to further extend contact imaging to a k1 near 0.30. While there are advantages and disadvantages for any potential RET, the benefits of not having to solve the phase assignment problem (which can lead to unresolvable phase conflicts), of it being a single reticle - single exposure technique, and its application to multiple layers within a device (clear field and dark field) make CPL an attractive, cost effective solution to low k1 imaging. However, real semiconductor circuit designs consist of much more than regular arrays of contact holes and a method to define the CPL reticle design for a full chip circuit pattern is required in order for this technique to be feasible in volume manufacturing. Interference Mapping Lithography (IML) is a novel approach for defining optimum reticle patterns based on the imaging conditions that will be used when the wafer is exposed. Figure 1 shows an interference map for an isolated contact simulated using ASML /1150 settings of 0.75NA and 0.92/0.72/30deg Quasar illumination. This technique provides a model-based approach for placing all types features (scattering bars, anti-scattering bars, non-printing assist features, phase shifted and non-phase shifted) for the purpose of enhancing the resolution of the target pattern and it can be applied to any reticle type including binary (COG), attenuated phase shifting mask (attPSM), alternating aperture phase shifting mask (altPSM), and CPL. In this work, we investigate the application of IML to generate CPL reticle designs for random contact patterns that are typical for 65nm node logic devices. We examine the critical issues related to using CPL with Interference Mapping Lithography including controlling side lobe printing, contact patterns with odd symmetry, forbidden pitch regions, and reticle manufacturing constraints. Multiple methods for deriving the interference map used to define reticle patterns for various RET's will be discussed. CPL reticle designs that were created from implementing automated algorithms for contact pattern decomposition using MaskWeaver will also be presented.

Using Visualization to Generalize on Quadratic Patterning Tasks

ERIC Educational Resources Information Center

Kirwan, J. Vince

2017-01-01

Patterning tasks engage students in a core aspect of algebraic thinking-generalization (Kaput 2008). The National Council of Teachers of Mathematics (NCTM) Algebra Standard states that students in grades 9-12 should "generalize patterns using explicitly defined and recursively defined functions" (NCTM 2000, p. 296). Although educators…

Antenna with Dielectric Having Geometric Patterns

NASA Technical Reports Server (NTRS)

Dudley, Kenneth L. (Inventor); Cravey, Robin L. (Inventor); Connell, John W. (Inventor); Ghose, Sayata (Inventor); Watson, Kent A. (Inventor); Smith, Jr., Joseph G. (Inventor); Elliott, Holly A. (Inventor)

2013-01-01

An antenna includes a ground plane, a dielectric disposed on the ground plane, and an electrically-conductive radiator disposed on the dielectric. The dielectric includes at least one layer of a first dielectric material and a second dielectric material that collectively define a dielectric geometric pattern, which may comprise a fractal geometry. The radiator defines a radiator geometric pattern, and the dielectric geometric pattern is geometrically identical, or substantially geometrically identical, to the radiator geometric pattern.

Suppression of friction by mechanical vibrations.

PubMed

Capozza, Rosario; Vanossi, Andrea; Vezzani, Alessandro; Zapperi, Stefano

2009-08-21

Mechanical vibrations are known to affect frictional sliding and the associated stick-slip patterns causing sometimes a drastic reduction of the friction force. This issue is relevant for applications in nanotribology and to understand earthquake triggering by small dynamic perturbations. We study the dynamics of repulsive particles confined between a horizontally driven top plate and a vertically oscillating bottom plate. Our numerical results show a suppression of the high dissipative stick-slip regime in a well-defined range of frequencies that depends on the vibrating amplitude, the normal applied load, the system inertia and the damping constant. We propose a theoretical explanation of the numerical results and derive a phase diagram indicating the region of parameter space where friction is suppressed. Our results allow to define better strategies for the mechanical control of friction.

[Emotional processing in patients with a dissocial personality disorder subtype "psychopathy" according to PCL-R].

PubMed

Weber, Tatjana; Sommer, Monika; Hajak, Göran; Müller, Jürgen

2004-11-01

Functional MRI was used to test the effects of the deficient emotional responsiveness of psychopathic patients on cognitive processes. We used a Simon-paradigm, in which ten healthy volunteers and ten patients with a diagnosis of "psychopathy" (defined by Hare Psychopathy Checklist Revised) have to select their spatially defined responses on the basis of a nonspatial stimuli feature. For the emotion induction pictures from the International Affective Picture System (IAPS) were selected. At the beginning and intermediated by the Simon-paradigm blocks of positive, negative or neutral pictures were presented. Patients with "psychopathy" exhibited untypical activation patterns in amygdala and prefrontal regions during interferences between negative or positive stimulations and cognitive tasks. These results demonstrated disturbed regulation of emotion-cognition-interaction in "psychopathy" according to PCL-R.

Subsidence and Rebound in California's Central Valley: Effects of Pumping, Geology, and Precipitation

NASA Astrophysics Data System (ADS)

Farr, T. G.; Fairbanks, A.

2017-12-01

Recent rains in California caused a pause, and even a reversal in some areas, of the subsidence that has plagued the Central Valley for decades. The 3 main drivers of surface deformation in the Central Valley are: Subsurface hydro-geology, precipitation and surface water deliveries, and groundwater pumping. While the geology is relatively fixed in time, water inputs and outputs vary greatly both in time and space. And while subsurface geology and water inputs are reasonably well-known, information about groundwater pumping amounts and rates is virtually non-existent in California. We have derived regional maps of surface deformation in the region for the period 2006 - present which allow reconstruction of seasonal and long-term changes. In order to understand the spatial and temporal patterns of subsidence and rebound in the Central Valley, we have been compiling information on the geology and water inputs and have attempted to infer pumping rates using maps of fallowed fields and published pumping information derived from hydrological models. In addition, the spatial and temporal patterns of hydraulic head as measured in wells across the region allow us to infer the spatial and temporal patterns of groundwater pumping and recharge more directly. A better understanding of how different areas (overlying different stratigraphy) of the Central Valley respond to water inputs and outputs will allow a predictive capability, potentially defining sustainable pumping rates related to water inputs. * work performed under contract to NASA and the CA Dept. of Water Resources

Juxtaposed genes in 7q21-22 amplicon contribute for two major gastric cancer sub-Types by mutual exclusive expression.

PubMed

Tamilzhalagan, Sembulingam; Muthuswami, Muthulakshmi; Ganesan, Kumaresan

2017-04-01

Genomic Copy Number Variations (CNV) and the associated gene signatures are useful for cancer prognosis, diagnosis, and targeted therapeutics. Earlier, 7q21-22 region was reported for frequent amplification in gastric cancer and potential candidate genes were identified. An analysis of the expression pattern of the 159 genes located in this amplicon revealed the consistent elevated expression of 21 genes in gastric tumors. These genes are closely arranged within the 20 Mb region, and they showed a bimodal expression pattern. SHFM1 and 14 other genes are expressed in intestinal type gastric tumors. COL1A2 and PCOLCE genes of this region are expressed in diffuse type gastric tumors. Similarly, genome-wide expression neighbors of SHFM1 and COL1A2 also showed mutually exclusive expression pattern, and stratify intestinal and diffuse type gastric tumors. The expression of COL1A2 gene-set is associated with poor prognosis, whereas the SHFM1 gene-set is associated with better prognosis among the gastric cancer patients. Despite being physical neighbors, the SHFM1 and COL1A2 genes express differentially in the two major clinical sub-types of gastric cancer in a mutually exclusive manner. The tight gene regulations operating between these juxtaposed genes deserve investigation to understand the molecular regulatory switch defining the determinants of the gastric cancer sub-types. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Genome-Wide Analysis of bZIP-Encoding Genes in Maize

PubMed Central

Wei, Kaifa; Chen, Juan; Wang, Yanmei; Chen, Yanhui; Chen, Shaoxiang; Lin, Yina; Pan, Si; Zhong, Xiaojun; Xie, Daoxin

2012-01-01

In plants, basic leucine zipper (bZIP) proteins regulate numerous biological processes such as seed maturation, flower and vascular development, stress signalling and pathogen defence. We have carried out a genome-wide identification and analysis of 125 bZIP genes that exist in the maize genome, encoding 170 distinct bZIP proteins. This family can be divided into 11 groups according to the phylogenetic relationship among the maize bZIP proteins and those in Arabidopsis and rice. Six kinds of intron patterns (a–f) within the basic and hinge regions are defined. The additional conserved motifs have been identified and present the group specificity. Detailed three-dimensional structure analysis has been done to display the sequence conservation and potential distribution of the bZIP domain. Further, we predict the DNA-binding pattern and the dimerization property on the basis of the characteristic features in the basic and hinge regions and the leucine zipper, respectively, which supports our classification greatly and helps to classify 26 distinct subfamilies. The chromosome distribution and the genetic analysis reveal that 58 ZmbZIP genes are located in the segmental duplicate regions in the maize genome, suggesting that the segment chromosomal duplications contribute greatly to the expansion of the maize bZIP family. Across the 60 different developmental stages of 11 organs, three apparent clusters formed represent three kinds of different expression patterns among the ZmbZIP gene family in maize development. A similar but slightly different expression pattern of bZIPs in two inbred lines displays that 22 detected ZmbZIP genes might be involved in drought stress. Thirteen pairs and 143 pairs of ZmbZIP genes show strongly negative and positive correlations in the four distinct fungal infections, respectively, based on the expression profile and Pearson's correlation coefficient analysis. PMID:23103471

Function and Dynamics of Auxin and Carbohydrates during Earlywood/Latewood Transition in Scots Pine1

PubMed Central

Uggla, Claes; Magel, Elisabeth; Moritz, Thomas; Sundberg, Björn

2001-01-01

In temperate regions the annual pattern of wood development is characterized by the formation of radially narrow and thick walled latewood cells. This takes place at the later part of the growing season when cambial cell division declines. To gain new insight into the regulation of this process, micro-analytical techniques were used to visualize the distribution of indole-3-acetic acid (IAA), soluble carbohydrates, and activities of sucrose (Suc)-metabolizing enzymes across the cambial region tissues in Scots pine (Pinus sylvestris). The total amount of IAA in the cambial region did not change with latewood initiation. But its radial distribution pattern was altered, resulting in an increased concentration in the cambial meristem and its recent derivatives. Thus, initiation of latewood formation and cessation of cambial cell division is not a consequence of decreased IAA concentrations in dividing and expanding cells. Rather, IAA most likely has a role in defining the altered developmental pattern associated with latewood formation. Carbohydrates and enzyme activities showed distinctive radial distribution patterns. Suc peaked in the phloem and decreased sharply to low levels across the cambial zone, whereas fructose and glucose reached their highest levels in the maturing tracheids. Suc synthase was the dominating Suc cleaving enzyme with a peak in the secondary wall-forming tracheids and in the phloem. Soluble acid invertase peaked in dividing and expanding cells. Suc-phosphate synthase had its highest activities in the phloem. Activities of cell wall bound invertase were low. The absence of major seasonal variations indicates that carbohydrate availability is not a trigger for latewood initiation. However, steep concentration gradients of the sugars suggest a role for sugar signaling in vascular development. PMID:11299382

Function and dynamics of auxin and carbohydrates during earlywood/latewood transition in scots pine.

PubMed

Uggla, C; Magel, E; Moritz, T; Sundberg, B

2001-04-01

In temperate regions the annual pattern of wood development is characterized by the formation of radially narrow and thick walled latewood cells. This takes place at the later part of the growing season when cambial cell division declines. To gain new insight into the regulation of this process, micro-analytical techniques were used to visualize the distribution of indole-3-acetic acid (IAA), soluble carbohydrates, and activities of sucrose (Suc)-metabolizing enzymes across the cambial region tissues in Scots pine (Pinus sylvestris). The total amount of IAA in the cambial region did not change with latewood initiation. But its radial distribution pattern was altered, resulting in an increased concentration in the cambial meristem and its recent derivatives. Thus, initiation of latewood formation and cessation of cambial cell division is not a consequence of decreased IAA concentrations in dividing and expanding cells. Rather, IAA most likely has a role in defining the altered developmental pattern associated with latewood formation. Carbohydrates and enzyme activities showed distinctive radial distribution patterns. Suc peaked in the phloem and decreased sharply to low levels across the cambial zone, whereas fructose and glucose reached their highest levels in the maturing tracheids. Suc synthase was the dominating Suc cleaving enzyme with a peak in the secondary wall-forming tracheids and in the phloem. Soluble acid invertase peaked in dividing and expanding cells. Suc-phosphate synthase had its highest activities in the phloem. Activities of cell wall bound invertase were low. The absence of major seasonal variations indicates that carbohydrate availability is not a trigger for latewood initiation. However, steep concentration gradients of the sugars suggest a role for sugar signaling in vascular development.

Mapping the Sedna-Lavinia Region of Venus

NASA Technical Reports Server (NTRS)

Campbell, Bruce A.; Anderson, Ross F.

2008-01-01

Geologic mapping of Venus at 1:5 M scale has shown in great detail the flow complexes of volcanoes, coronae, and shield fields, and the varying structural patterns that differentiate tesserae from corona rims and isolated patches of densely lineated terrain. In most cases, however, the lower-elevation plains between the higher-standing landforms are discriminated only on the basis of potentially secondary features such as late-stage lava flooding or tectonic overprinting. This result, in which volcanoes and tesserae appear as "islands in the sea," places weak constraints on the relative age of large upland regions and the nature of the basement terrain. In this work, we focus on the spatial distribution and topography of densely lineated and tessera units over a large region of Venus, and their relationship to apparently later corona and shield flow complexes. The goal is to identify likely connections between patches of deformed terrain that suggest earlier features of regional extent, and to compare the topography of linked patches with other such clusters as a guide to whether they form larger tracts beneath the plains. Mapping Approach. We are mapping the region from 57S to 57N, 300E-60E. Since the 1:5 M quadrangles emphasize detail of tessera structure and corona/edifice flows, we simply adopt the outlines of these features as they relate to the outcrops of either "densely lineated terrain" or tessera (Fig. 1). The densely lineated material is mapped in many quadrangles based on pervasive structural deformation, typically with a single major axis (in contrast to the overlapping orthogonal patterns on tesserae). This unit definition is often extended to include material of corona rims. We do not at present differentiate between plains units, since earlier efforts show that their most defining attributes may be secondary to the original emplacement (e.g., lobate or sheet-like flooding by thin flow units, tectonic patterns related to regional and localized stress regimes) [1].

Phone traffic as a measurement of agricultural events

NASA Astrophysics Data System (ADS)

Martín, Samuel; Borondo, Javier; Morales, Alfredo; Losada, Juan Carlos; Tarquis, Ana M.; Benito, Rosa Maria

2015-04-01

Inspired by empirical studies of networked systems such as the Internet, social networks, and biological networks, researchers have in recent years developed a variety of techniques and models to help us understand or predict the behaviour of these systems (1). However, it has been recently when global food system has been seen as a complex web of production, processing, storage and transportation opening new challenges in their analysis. Agricultural activities in developing countries remain as important today as in the 1950s implying seasonal workers mobilization. The proliferation of mobile phones (MPs) offers an unprecedented tool to analyze human activity mapping. We would like to mention that in developed countries, the number of MP subscribers has surpassed the total population, with a penetration rate now reaching 121%, whereas in developing countries, it is as high as 90% and continuing to rise (2). As an example, we have analyzed the impact that agricultural activities, such as the growing of groundnut, have on Senegal. To this end we have analyzed the Normalized Difference Vegetation Index (NDVI) time series of the whole of Senegal and spotted the regions where groundnut is grown to identify the time period when this crop growth. By analyzing phone calls at each region of the country we found that a significant fraction of antennas exhibit two well defined peaks of activity corresponding with the begging and end of the growing season. Antennas located on regions identified as growing regions present this pattern. However, other antennas, located in non growing regions, such as Dakar, also present the two peaks pattern pointing out the synchronization between growing regions and key points in cities that emerges from the agricultural activity. References 1. Marta C. González, César A. Hidalgo and Albert-László Barabási (2008) Understanding individual human mobility patterns. Nature 453, 779-78. 2. International Telecommunication Union (2014) World Telecommunication Development Conference (WTDC-2014): Final Report. (ITU, Dubai, United Arab Emirates).

Quantitative assessments of water-use efficiency in Temperate Eurasian Steppe along an aridity gradient

PubMed Central

Chen, Yizhao; Li, Jianlong; Ju, Weimin; Ruan, Honghua; Qin, Zhihao; Huang, Yiye; Jeelani, Nasreen; Padarian, José; Propastin, Pavel

2017-01-01

Water-use efficiency (WUE), defined as the ratio of net primary productivity (NPP) to evapotranspiration (ET), is an important indicator to represent the trade-off pattern between vegetation productivity and water consumption. Its dynamics under climate change are important to ecohydrology and ecosystem management, especially in the drylands. In this study, we modified and used a late version of Boreal Ecosystem Productivity Simulator (BEPS), to quantify the WUE in the typical dryland ecosystems, Temperate Eurasian Steppe (TES). The Aridity Index (AI) was used to specify the terrestrial water availability condition. The regional results showed that during the period of 1999–2008, the WUE has a clear decreasing trend in the spatial distribution from arid to humid areas. The highest annual average WUE was in dry and semi-humid sub-region (DSH) with 0.88 gC mm-1 and the lowest was in arid sub-region (AR) with 0.22 gC mm-1. A two-stage pattern of WUE was found in TES. That is, WUE would enhance with lower aridity stress, but decline under the humid environment. Over 65% of the region exhibited increasing WUE. This enhancement, however, could not indicate that the grasslands were getting better because the NPP even slightly decreased. It was mainly attributed to the reduction of ET over 70% of the region, which is closely related to the rainfall decrease. The results also suggested a similar negative spatial correlation between the WUE and the mean annual precipitation (MAP) at the driest and the most humid ends. This regional pattern reflected the different roles of water in regulating the terrestrial ecosystems under different aridity levels. This study could facilitate the understanding of the interactions between terrestrial carbon and water cycles, and thus contribute to a sustainable management of nature resources in the dryland ecosystems. PMID:28686667

Quantitative assessments of water-use efficiency in Temperate Eurasian Steppe along an aridity gradient.

PubMed

Chen, Yizhao; Li, Jianlong; Ju, Weimin; Ruan, Honghua; Qin, Zhihao; Huang, Yiye; Jeelani, Nasreen; Padarian, José; Propastin, Pavel

2017-01-01

Water-use efficiency (WUE), defined as the ratio of net primary productivity (NPP) to evapotranspiration (ET), is an important indicator to represent the trade-off pattern between vegetation productivity and water consumption. Its dynamics under climate change are important to ecohydrology and ecosystem management, especially in the drylands. In this study, we modified and used a late version of Boreal Ecosystem Productivity Simulator (BEPS), to quantify the WUE in the typical dryland ecosystems, Temperate Eurasian Steppe (TES). The Aridity Index (AI) was used to specify the terrestrial water availability condition. The regional results showed that during the period of 1999-2008, the WUE has a clear decreasing trend in the spatial distribution from arid to humid areas. The highest annual average WUE was in dry and semi-humid sub-region (DSH) with 0.88 gC mm-1 and the lowest was in arid sub-region (AR) with 0.22 gC mm-1. A two-stage pattern of WUE was found in TES. That is, WUE would enhance with lower aridity stress, but decline under the humid environment. Over 65% of the region exhibited increasing WUE. This enhancement, however, could not indicate that the grasslands were getting better because the NPP even slightly decreased. It was mainly attributed to the reduction of ET over 70% of the region, which is closely related to the rainfall decrease. The results also suggested a similar negative spatial correlation between the WUE and the mean annual precipitation (MAP) at the driest and the most humid ends. This regional pattern reflected the different roles of water in regulating the terrestrial ecosystems under different aridity levels. This study could facilitate the understanding of the interactions between terrestrial carbon and water cycles, and thus contribute to a sustainable management of nature resources in the dryland ecosystems.

Biodiversity patterns along ecological gradients: unifying β-diversity indices.

PubMed

Szava-Kovats, Robert C; Pärtel, Meelis

2014-01-01

Ecologists have developed an abundance of conceptions and mathematical expressions to define β-diversity, the link between local (α) and regional-scale (γ) richness, in order to characterize patterns of biodiversity along ecological (i.e., spatial and environmental) gradients. These patterns are often realized by regression of β-diversity indices against one or more ecological gradients. This practice, however, is subject to two shortcomings that can undermine the validity of the biodiversity patterns. First, many β-diversity indices are constrained to range between fixed lower and upper limits. As such, regression analysis of β-diversity indices against ecological gradients can result in regression curves that extend beyond these mathematical constraints, thus creating an interpretational dilemma. Second, despite being a function of the same measured α- and γ-diversity, the resultant biodiversity pattern depends on the choice of β-diversity index. We propose a simple logistic transformation that rids beta-diversity indices of their mathematical constraints, thus eliminating the possibility of an uninterpretable regression curve. Moreover, this transformation results in identical biodiversity patterns for three commonly used classical beta-diversity indices. As a result, this transformation eliminates the difficulties of both shortcomings, while allowing the researcher to use whichever beta-diversity index deemed most appropriate. We believe this method can help unify the study of biodiversity patterns along ecological gradients.

Biodiversity Patterns along Ecological Gradients: Unifying β-Diversity Indices

PubMed Central

Szava-Kovats, Robert C.; Pärtel, Meelis

2014-01-01

Ecologists have developed an abundance of conceptions and mathematical expressions to define β-diversity, the link between local (α) and regional-scale (γ) richness, in order to characterize patterns of biodiversity along ecological (i.e., spatial and environmental) gradients. These patterns are often realized by regression of β-diversity indices against one or more ecological gradients. This practice, however, is subject to two shortcomings that can undermine the validity of the biodiversity patterns. First, many β-diversity indices are constrained to range between fixed lower and upper limits. As such, regression analysis of β-diversity indices against ecological gradients can result in regression curves that extend beyond these mathematical constraints, thus creating an interpretational dilemma. Second, despite being a function of the same measured α- and γ-diversity, the resultant biodiversity pattern depends on the choice of β-diversity index. We propose a simple logistic transformation that rids beta-diversity indices of their mathematical constraints, thus eliminating the possibility of an uninterpretable regression curve. Moreover, this transformation results in identical biodiversity patterns for three commonly used classical beta-diversity indices. As a result, this transformation eliminates the difficulties of both shortcomings, while allowing the researcher to use whichever beta-diversity index deemed most appropriate. We believe this method can help unify the study of biodiversity patterns along ecological gradients. PMID:25330181

Alteration of travel patterns with vision loss from glaucoma and macular degeneration.

PubMed

Curriero, Frank C; Pinchoff, Jessie; van Landingham, Suzanne W; Ferrucci, Luigi; Friedman, David S; Ramulu, Pradeep Y

2013-11-01

The distance patients can travel outside the home influences how much of the world they can sample and to what extent they can live independently. Recent technological advances have allowed travel outside the home to be directly measured in patients' real-world routines. To determine whether decreased visual acuity (VA) from age-related macular degeneration (AMD) and visual field (VF) loss from glaucoma are associated with restricted travel patterns in older adults. Cross-sectional study. Patients were recruited from an eye clinic, while travel patterns were recorded during their real-world routines using a cellular tracking device. Sixty-one control subjects with normal vision, 84 subjects with glaucoma with bilateral VF loss, and 65 subjects with AMD with bilateral or severe unilateral loss of VA had their location tracked every 15 minutes between 7 am and 11 pm for 7 days using a tracking device. Average daily excursion size (defined as maximum distance away from home) and average daily excursion span (defined as maximum span of travel) were defined for each individual. The effects of vision loss on travel patterns were evaluated after controlling for individual and geographic factors. In multivariable models comparing subjects with AMD and control subjects, average excursion size and span decreased by approximately one-quarter mile for each line of better-eye VA loss (P ≤ .03 for both). Similar but not statistically significant associations were observed between average daily excursion size and span for severity of better-eye VF loss in subjects with glaucoma and control subjects. Being married or living with someone and younger age were associated with more distant travel, while less-distant travel was noted for older individuals, African Americans, and those living in more densely populated regions. Age-related macular degeneration-related loss of VA, but not glaucoma-related loss of VF, is associated with restriction of travel to more nearby locations. This constriction of life space may impact quality of life and restrict access to services.

Multiscale analysis of the fracture pattern in granite, example of Tamariu's granite, Catalunya.

NASA Astrophysics Data System (ADS)

Bertrand, L.; LeGarzic, E.; Géraud, Y.; Diraison, M.

2012-04-01

Crystalline rocks can be the host of important fluid flow and therefore they can provide a good reservoir potential. In this kind of rocks, the matrice porosity is in general low and a large part of the permeability is governed by the fracture pattern. Thus, they are the first interest of studies in order to characterize and model the fluid flows. Actual reservoirs are underground, and the only access to the fracture pattern is with boreholes and seismic lines. Those methods are investigating different scales and dimensions: seismic is in 3D at a global scale whereas boreholes are 1D at a localized scale. To make the link between the different data, it is necessary to study field analogues where such fractured rocks are outcropping. Tamariu's granite, in Catalunya, has recently been studied as a field analogue of a fractured reservoir. The previous studies have lead to define structural blocks at different scales, linked to the regional deformation. This study's aim is to characterize the internal fracturation of a single structural block with a statistical analysis. We used one dimension scan lines at the scale of a block and 2 dimensions mapping at a more precise scale until the grain scale. The data highlighted that the fracture and fault lengths have a power law relation in 8 orders of scales. So this power law is stretching between seismic and borehole scales. Therefore, the data fit with a very good trust in the power law exponent, which is very well defined. The link between the reservoir scale faults and the internal block fracturation has also been defined in term of the structures orientation. Finally, a comparison between the 1D and 2D measurement could be done. The 1D scan lines show correctly the different fractures families but samples incompletely a part the fracture pattern, whereas the 2D maps which show more the global trends of the fractures and could lose some minor trends orientations.

The evolution of PBMA: towards a macro-level priority setting framework for health regions.

PubMed

Mitton, Craig R; Donaldson, Cam; Waldner, Howard; Eagle, Chris

2003-11-01

To date, relatively little work on priority setting has been carried out at a macro-level across major portfolios within integrated health care organizations. This paper describes a macro marginal analysis (MMA) process for setting priorities and allocating resources in health authorities, based on work carried out in a major urban health region in Alberta, Canada. MMA centers around an expert working group of managers and clinicians who are charged with identifying areas for resource re-allocation on an ongoing basis. Trade-offs between services are based on locally defined criteria and are informed by multiple inputs such as evidence from the literature and local expert opinion. The approach is put forth as a significant improvement on historical resource allocation patterns.

Fast progressive lower motor neuron disease is an ALS variant: A two-centre tract of interest-based MRI data analysis.

PubMed

Müller, Hans-Peter; Agosta, Federica; Riva, Nilo; Spinelli, Edoardo G; Comi, Giancarlo; Ludolph, Albert C; Filippi, Massimo; Kassubek, Jan

2018-01-01

The criteria for assessing upper motor neuron pathology in pure lower motor neuron disease (LMND) still remain a major issue of debate with respect to the clinical classification as an amyotrophic lateral sclerosis (ALS) variant. The study was designed to investigate white matter damage by a hypothesis-guided tract-of-interest-based approach in patients with LMND compared with healthy controls and ´classical´ ALS patients in order to identify in vivo brain structural changes according to the neuropathologically defined ALS affectation pattern. Data were pooled from two previous studies at two different study sites (Ulm, Germany and Milano, Italy). DTI-based white matter integrity mapping was performed by voxelwise statistical comparison and by a tractwise analysis of fractional anisotropy (FA) maps according to the ALS-staging pattern for 65 LMND patients (clinically differentiated in fast and slow progressors) vs. 92 matched controls and 101 ALS patients with a 'classical' phenotype to identify white matter structural alterations. The analysis of white matter structural connectivity by regional FA reductions demonstrated the characteristic alteration patterns along the CST and also in frontal and prefrontal brain areas in LMND patients compared to controls and ALS. Fast progressing LMND showed substantial involvement, like in ALS, while slow progressors showed less severe alterations. In the tract-specific analysis according to the ALS-staging pattern, fast progressing LMND showed significant alterations of ALS-related tract systems as compared to slow progressors and controls. This study showed an affectation pattern for corticoefferent fibers in LMND with fast disease progression as defined for ALS, that way confirming the hypothesis that fast progressing LMND is a phenotypical variant of ALS.

Prediction of monthly rainfall on homogeneous monsoon regions of India based on large scale circulation patterns using Genetic Programming

NASA Astrophysics Data System (ADS)

Kashid, Satishkumar S.; Maity, Rajib

2012-08-01

SummaryPrediction of Indian Summer Monsoon Rainfall (ISMR) is of vital importance for Indian economy, and it has been remained a great challenge for hydro-meteorologists due to inherent complexities in the climatic systems. The Large-scale atmospheric circulation patterns from tropical Pacific Ocean (ENSO) and those from tropical Indian Ocean (EQUINOO) are established to influence the Indian Summer Monsoon Rainfall. The information of these two large scale atmospheric circulation patterns in terms of their indices is used to model the complex relationship between Indian Summer Monsoon Rainfall and the ENSO as well as EQUINOO indices. However, extracting the signal from such large-scale indices for modeling such complex systems is significantly difficult. Rainfall predictions have been done for 'All India' as one unit, as well as for five 'homogeneous monsoon regions of India', defined by Indian Institute of Tropical Meteorology. Recent 'Artificial Intelligence' tool 'Genetic Programming' (GP) has been employed for modeling such problem. The Genetic Programming approach is found to capture the complex relationship between the monthly Indian Summer Monsoon Rainfall and large scale atmospheric circulation pattern indices - ENSO and EQUINOO. Research findings of this study indicate that GP-derived monthly rainfall forecasting models, that use large-scale atmospheric circulation information are successful in prediction of All India Summer Monsoon Rainfall with correlation coefficient as good as 0.866, which may appears attractive for such a complex system. A separate analysis is carried out for All India Summer Monsoon rainfall for India as one unit, and five homogeneous monsoon regions, based on ENSO and EQUINOO indices of months of March, April and May only, performed at end of month of May. In this case, All India Summer Monsoon Rainfall could be predicted with 0.70 as correlation coefficient with somewhat lesser Correlation Coefficient (C.C.) values for different 'homogeneous monsoon regions'.

Fluvial Channel Networks as Analogs for the Ridge-Forming Unit, Sinus Meridiani, Mars

NASA Technical Reports Server (NTRS)

Wilkinson, M. J.; du Bois, J. B.

2010-01-01

Fluvial models have been generally discounted as analogs for the younger layered rock units of Sinus Meridiani. A fluvial model based on the large fluvial fan provides a possibly close analog for various features of the sinuous ridges of the etched, ridge-forming unit (RFU) in particular. The close spacing of the RFU ridges, their apparently chaotic orientations, and their organization in dense networks all appear unlike classical stream channel patterns. However, drainage patterns on large fluvial fans low-angle, fluvial aggradational features, 100s of km long, documented worldwide by us provide parallels. Some large fan characteristics resemble those of classical floodplains, but many differences have been demonstrated. One major distinction relevant to the RFU is that channel landscapes of large fans can dominate large areas (1.2 million km2 in one S. American study area). We compare channel morphologies on large fans in the southern Sahara Desert with ridge patterns in Sinus Meridiani (fig 1). Stream channels are the dominant landform on large terrestrial fans: they may equate to the ubiquitous, sinuous, elongated ridges of the RFU that cover areas region wide. Networks of convergent/divergent and crossing channels may equate to similar features in the ridge networks. Downslope divergence is absent in channels of terrestrial upland erosional landscapes (fig. 1, left), whereas it is common to both large fans (fig. 1, center) and RFU ridge patterns (fig 1, right downslope defined as the regional NW slope of Sinus Meridiani). RFU ridge orientation, judged from those areas apparently devoid of impact crater control, is broadly parallel with the regional slope (arrow, fig. 1, right), as is mean orientation of major channels on large fans (arrow, fig. 1, center). High densities per unit area characterize fan channels and martian ridges reaching an order of magnitude higher than those in uplands just upstream of the terrestrial study areas fig. 1. In concert with several other regional features, these morphological similarities argue for the RFU as a possibly fluvial unit.

Seasonal variation in orthopedic health services utilization in Switzerland: the impact of winter sport tourism.

PubMed

Matter-Walstra, Klazien; Widmer, Marcel; Busato, André

2006-03-03

Climate- or holiday-related seasonality in hospital admission rates is well known for many diseases. However, little research has addressed the impact of tourism on seasonality in admission rates. We therefore investigated the influence of tourism on emergency admission rates in Switzerland, where winter and summer leisure sport activities in large mountain regions can generate orthopedic injuries. Using small area analysis, orthopedic hospital service areas (HSAo) were evaluated for seasonality in emergency admission rates. Winter sport areas were defined using guest bed accommodation rate patterns of guest houses and hotels located above 1000 meters altitude that show clear winter and summer peak seasons. Emergency admissions (years 2000-2002, n = 135'460) of local and nonlocal HSAo residents were evaluated. HSAo were grouped according to their area type (regular or winter sport area) and monthly analyses of admission rates were performed. Of HSAo within the defined winter sport areas 70.8% show a seasonal, summer-winter peak hospital admission rate pattern and only 1 HSAo outside the defined winter sport areas shows such a pattern. Seasonal hospital admission rates in HSAo in winter sport areas can be up to 4 times higher in winter than the intermediate seasons, and they are almost entirely due to admissions of nonlocal residents. These nonlocal residents are in general -and especially in winter- younger than local residents, and nonlocal residents have a shorter length of stay in winter sport than in regular areas. The overall geographic distribution of nonlocal residents admitted for emergencies shows highest rates during the winter as well as the summer in the winter sport areas. Small area analysis using orthopedic hospital service areas is a reliable method for the evaluation of seasonality in hospital admission rates. In Switzerland, HSAo defined as winter sport areas show a clear seasonal fluctuation in admission rates of only nonlocal residents, whereas HSAo defined as regular, non-winter sport areas do not show such seasonality. We conclude that leisure sport, and especially ski/snowboard tourism demands great flexibility in hospital beds, staff and resource planning in these areas.

Seasonal variation in orthopedic health services utilization in Switzerland: The impact of winter sport tourism

PubMed Central

Matter-Walstra, Klazien; Widmer, Marcel; Busato, André

2006-01-01

Background Climate- or holiday-related seasonality in hospital admission rates is well known for many diseases. However, little research has addressed the impact of tourism on seasonality in admission rates. We therefore investigated the influence of tourism on emergency admission rates in Switzerland, where winter and summer leisure sport activities in large mountain regions can generate orthopedic injuries. Methods Using small area analysis, orthopedic hospital service areas (HSAo) were evaluated for seasonality in emergency admission rates. Winter sport areas were defined using guest bed accommodation rate patterns of guest houses and hotels located above 1000 meters altitude that show clear winter and summer peak seasons. Emergency admissions (years 2000–2002, n = 135'460) of local and nonlocal HSAo residents were evaluated. HSAo were grouped according to their area type (regular or winter sport area) and monthly analyses of admission rates were performed. Results Of HSAo within the defined winter sport areas 70.8% show a seasonal, summer-winter peak hospital admission rate pattern and only 1 HSAo outside the defined winter sport areas shows such a pattern. Seasonal hospital admission rates in HSAo in winter sport areas can be up to 4 times higher in winter than the intermediate seasons, and they are almost entirely due to admissions of nonlocal residents. These nonlocal residents are in general -and especially in winter- younger than local residents, and nonlocal residents have a shorter length of stay in winter sport than in regular areas. The overall geographic distribution of nonlocal residents admitted for emergencies shows highest rates during the winter as well as the summer in the winter sport areas. Conclusion Small area analysis using orthopedic hospital service areas is a reliable method for the evaluation of seasonality in hospital admission rates. In Switzerland, HSAo defined as winter sport areas show a clear seasonal fluctuation in admission rates of only nonlocal residents, whereas HSAo defined as regular, non-winter sport areas do not show such seasonality. We conclude that leisure sport, and especially ski/snowboard tourism demands great flexibility in hospital beds, staff and resource planning in these areas. PMID:16512923

Variability of cold season surface air temperature over northeastern China and its linkage with large-scale atmospheric circulations

NASA Astrophysics Data System (ADS)

Zhuang, Yuanhuang; Zhang, Jingyong; Wang, Lin

2018-05-01

Cold temperature anomalies and extremes have profound effects on the society, the economy, and the environment of northeastern China (NEC). In this study, we define the cold season as the months from October to April, and investigate the variability of cold season surface air temperature (CSAT) over NEC and its relationships with large-scale atmospheric circulation patterns for the period 1981-2014. The empirical orthogonal function (EOF) analysis shows that the first EOF mode of the CSAT over NEC is characterized by a homogeneous structure that describes 92.2% of the total variance. The regionally averaged CSAT over NEC is closely linked with the Arctic Oscillation ( r = 0.62, 99% confidence level) and also has a statistically significant relation with the Polar/Eurasian pattern in the cold season. The positive phases of the Arctic Oscillation and the Polar/Eurasian pattern tend to result in a positive geopotential height anomaly over NEC and a weakened East Asian winter monsoon, which subsequently increase the CSAT over NEC by enhancing the downward solar radiation, strengthening the subsidence warming and warm air advection. Conversely, the negative phases of these two climate indices result in opposite regional atmospheric circulation anomalies and decrease the CSAT over NEC.

Temporally variable environments maintain more beta-diversity in Mediterranean landscapes

NASA Astrophysics Data System (ADS)

Martin, Beatriz; Ferrer, Miguel

2015-10-01

We examined the relationships between different environmental factors and the alpha and beta-diversity of terrestrial vertebrates (birds, mammals, amphibians and reptiles) in a Mediterranean region at the landscape level. We investigated whether the mechanisms underlying alpha and beta-diversity patterns are influenced by energy availability, habitat heterogeneity and temporal variability and if the drivers of the diversity patterns differed between both components of diversity. We defined alpha-diversity as synonym of species richness whereas beta-diversity was measured as distinctiveness. We evaluated a total of 13 different predictors using generalized linear mixed model (GLMM) analysis. Habitat spatial heterogeneity increased alpha-diversity, but contrastingly, it did not significantly affect beta-diversity among sites. Disturbed landscapes may show higher habitat spatial variation and higher alpha-diversity due to the contribution of highly generalist species that are wide-distributed and do not differ in composition (beta-diversity) among different sites within the region. Contrastingly, higher beta-diversity levels were negatively related to more stable sites in terms of temporal environmental variation. This negative relationship between environmental stability and beta-diversity levels is explained in terms of species adaptation to the local environmental conditions. Our study highlights the importance of temporal environmental variability in maintaining beta-diversity patterns under highly variable environmental conditions.

Where and When do Species Interactions Set Range Limits?

PubMed

Louthan, Allison M; Doak, Daniel F; Angert, Amy L

2015-12-01

A long-standing theory, originating with Darwin, suggests that abiotic forces set species range limits at high latitude, high elevation, and other abiotically 'stressful' areas, while species interactions set range limits in apparently more benign regions. This theory is of considerable importance for both basic and applied ecology, and while it is often assumed to be a ubiquitous pattern, it has not been clearly defined or broadly tested. We review tests of this idea and dissect how the strength of species interactions must vary across stress gradients to generate the predicted pattern. We conclude by suggesting approaches to better test this theory, which will deepen our understanding of the forces that determine species ranges and govern responses to climate change. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sidewall patterning—a new wafer-scale method for accurate patterning of vertical silicon structures

NASA Astrophysics Data System (ADS)

Westerik, P. J.; Vijselaar, W. J. C.; Berenschot, J. W.; Tas, N. R.; Huskens, J.; Gardeniers, J. G. E.

2018-01-01

For the definition of wafer scale micro- and nanostructures, in-plane geometry is usually controlled by optical lithography. However, options for precisely patterning structures in the out-of-plane direction are much more limited. In this paper we present a versatile self-aligned technique that allows for reproducible sub-micrometer resolution local modification along vertical silicon sidewalls. Instead of optical lithography, this method makes smart use of inclined ion beam etching to selectively etch the top parts of structures, and controlled retraction of a conformal layer to define a hard mask in the vertical direction. The top, bottom or middle part of a structure could be selectively exposed, and it was shown that these exposed regions can, for example, be selectively covered with a catalyst, doped, or structured further.

Spiral and Rotor Patterns Produced by Fairy Ring Fungi

NASA Astrophysics Data System (ADS)

Karst, N.; Dralle, D.; Thompson, S. E.

2014-12-01

Soil fungi fill many essential ecological and biogeochemical roles, e.g. decomposing litter, redistributing nutrients, and promoting biodiversity. Fairy ring fungi offer a rare glimpse into the otherwise opaque spatiotemporal dynamics of soil fungal growth, because subsurface mycelial patterns can be inferred from observations at the soil's surface. These observations can be made directly when the fungi send up fruiting bodies (e.g., mushrooms and toadstools), or indirectly via the effect the fungi have on neighboring organisms. Grasses in particular often temporarily thrive on the nutrients liberated by the fungus, creating bands of rich, dark green turf at the edge of the fungal mat. To date, only annular (the "ring" in fairy ring) and arc patterns have been described in the literature. We report observations of novel spiral and rotor pattern formation in fairy ring fungi, as seen in publically available high-resolution aerial imagery of 22 sites across the continental United States. To explain these new behaviors, we first demonstrate that a well-known model describing fairy ring formation is equivalent to the Gray-Scott reaction-diffusion model, which is known to support a wide range of dynamical behaviors, including annular traveling waves, rotors, spirals, and stable spatial patterns including spots and stripes. Bifurcation analysis and numerical simulation are then used to define the region of parameter space that supports spiral and rotor formation. We find that this region is adjacent to one within which typical fairy rings develop. Model results suggest simple experimental procedures that could potentially induce traditional ring structures to exhibit rotor or spiral dynamics. Intriguingly, the Gray-Scott model predicts that these same procedures could be used to solicit even richer patterns, including spots and stripes, which have not yet been identified in the field.

Spiral and Rotor Patterns Produced by Fairy Ring Fungi

NASA Astrophysics Data System (ADS)

Karst, N.; Dralle, D.; Thompson, S. E.

2015-12-01

Soil fungi fill many essential ecological and biogeochemical roles, e.g. decomposing litter, redistributing nutrients, and promoting biodiversity. Fairy ring fungi offer a rare glimpse into the otherwise opaque spatiotemporal dynamics of soil fungal growth, because subsurface mycelial patterns can be inferred from observations at the soil's surface. These observations can be made directly when the fungi send up fruiting bodies (e.g., mushrooms and toadstools), or indirectly via the effect the fungi have on neighboring organisms. Grasses in particular often temporarily thrive on the nutrients liberated by the fungus, creating bands of rich, dark green turf at the edge of the fungal mat. To date, only annular (the "ring" in fairy ring) and arc patterns have been described in the literature. We report observations of novel spiral and rotor pattern formation in fairy ring fungi, as seen in publically available high-resolution aerial imagery of 22 sites across the continental United States. To explain these new behaviors, we first demonstrate that a well-known model describing fairy ring formation is equivalent to the Gray-Scott reaction-diffusion model, which is known to support a wide range of dynamical behaviors, including annular traveling waves, rotors, spirals, and stable spatial patterns including spots and stripes. Bifurcation analysis and numerical simulation are then used to define the region of parameter space that supports spiral and rotor formation. We find that this region is adjacent to one within which typical fairy rings develop. Model results suggest simple experimental procedures that could potentially induce traditional ring structures to exhibit rotor or spiral dynamics. Intriguingly, the Gray-Scott model predicts that these same procedures could be used to solicit even richer patterns, including spots and stripes, which have not yet been identified in the field.

Comparison of clast and matrix dispersal in till: Charlo-Atholville area, north-central New Brunswick

USGS Publications Warehouse

Dickson, M.L.; Broster, B.E.; Parkhill, M.A.

2004-01-01

Striations and dispersal patterns for till clasts and matrix geochemistry are used to define flow directions of glacial transport across an area of about 800km2 in the Charlo-Atholville area of north-central New Brunswick. A total of 170 clast samples and 328 till matrix samples collected for geochemical analysis across the region, were analyzed for a total of 39 elements. Major lithologic contacts used here to delineate till clast provenance were based on recent bedrock mapping. Eleven known mineral occurrences and a gossan are used to define point source targets for matrix geochemical dispersal trains and to estimate probable distance and direction of transport from unknown sources. Clast trains are traceable for distances of approximately 10 km, whereas till geochemical dispersal patterns are commonly lost within 5 km of transport. Most dispersal patterns reflect more than a single direction of glacial transport. These data indicate that a single till sheet, 1-4 m thick, was deposited as the dominant ice-flow direction fluctuated between southeastward, eastward, and northward over the study area. Directions of early flow represent changes in ice sheet dominance, first from the northwest and then from the west. Locally, eastward and northward flow represent the maximum erosive phases. The last directions of flow are likely due to late glacial ice sheet drawdown towards the valley outlet at Baie des Chaleurs.

Magnetic resonance diffusion-perfusion mismatch in acute ischemic stroke: An update

PubMed Central

Chen, Feng; Ni, Yi-Cheng

2012-01-01

The concept of magnetic resonance perfusion-diffusion mismatch (PDM) provides a practical and approximate measure of the tissue at risk and has been increasingly applied for the evaluation of hyperacute and acute stroke in animals and patients. Recent studies demonstrated that PDM does not optimally define the ischemic penumbra; because early abnormality on diffusion-weighted imaging overestimates the infarct core by including part of the penumbra, and the abnormality on perfusion weighted imaging overestimates the penumbra by including regions of benign oligemia. To overcome these limitations, many efforts have been made to optimize conventional PDM. Various alternatives beyond the PDM concept are under investigation in order to better define the penumbra. The PDM theory has been applied in ischemic stroke for at least three purposes: to be used as a practical selection tool for stroke treatment; to test the hypothesis that patients with PDM pattern will benefit from treatment, while those without mismatch pattern will not; to be a surrogate measure for stroke outcome. The main patterns of PDM and its relation with clinical outcomes were also briefly reviewed. The conclusion was that patients with PDM documented more reperfusion, reduced infarct growth and better clinical outcomes compared to patients without PDM, but it was not yet clear that thrombolytic therapy is beneficial when patients were selected on PDM. Studies based on a larger cohort are currently under investigation to further validate the PDM hypothesis. PMID:22468186

Experiments on automatic classification of tissue malignancy in the field of digital pathology

NASA Astrophysics Data System (ADS)

Pereira, J.; Barata, R.; Furtado, Pedro

2017-06-01

Automated analysis of histological images helps diagnose and further classify breast cancer. Totally automated approaches can be used to pinpoint images for further analysis by the medical doctor. But tissue images are especially challenging for either manual or automated approaches, due to mixed patterns and textures, where malignant regions are sometimes difficult to detect unless they are in very advanced stages. Some of the major challenges are related to irregular and very diffuse patterns, as well as difficulty to define winning features and classifier models. Although it is also hard to segment correctly into regions, due to the diffuse nature, it is still crucial to take low-level features over individualized regions instead of the whole image, and to select those with the best outcomes. In this paper we report on our experiments building a region classifier with a simple subspace division and a feature selection model that improves results over image-wide and/or limited feature sets. Experimental results show modest accuracy for a set of classifiers applied over the whole image, while the conjunction of image division, per-region low-level extraction of features and selection of features, together with the use of a neural network classifier achieved the best levels of accuracy for the dataset and settings we used in the experiments. Future work involves deep learning techniques, adding structures semantics and embedding the approach as a tumor finding helper in a practical Medical Imaging Application.

Spatial and seasonal patterns in urban influence on regional concentrations of speciated aerosols across the United States

NASA Astrophysics Data System (ADS)

Hand, J. L.; Schichtel, B. A.; Malm, W. C.; Pitchford, M.; Frank, N. H.

2014-11-01

Monthly, seasonal, and annual mean estimates of urban influence on regional concentrations of major aerosol species were computed using speciated aerosol data from the rural IMPROVE network (Interagency Monitoring of Protected Visual Environments) and the United States Environmental Protection Agency's urban Chemical Speciation Network for the 2008 through 2011 period. Aggregated for sites across the continental United States, the annual mean and one standard error in urban excess (defined as the ratio of urban to nearby rural concentrations) was highest for elemental carbon (3.3 ± 0.2), followed by ammonium nitrate (2.5 ± 0.2), particulate organic matter (1.78 ± 0.08), and ammonium sulfate (1.23 ± 0.03). The seasonal variability in urban excess was significant for carbonaceous aerosols and ammonium nitrate in the West, in contrast to the low seasonal variability in the urban influence of ammonium sulfate. Generally for all species, higher excess values in the West were associated with localized urban sources while in the East excess was more regional in extent. In addition, higher excess values in the western United States in winter were likely influenced not only by differences in sources but also by combined meteorological and topographic effects. This work has implications for understanding the spatial heterogeneity of major aerosol species near the interface of urban and rural regions and therefore for designing appropriate air quality management strategies. In addition, the spatial patterns in speciated mass concentrations provide constraints for regional and global models.

Taxonomy of Mechanitis (f.) (Lepidoptera: Nymphalidae) from the west Colombian Andes: an integrative approach.

PubMed

Giraldo, C E; Uribe, S I

2012-12-01

Species identification in the butterfly genus Mechanitis (F.) (Lepidoptera: Nymphalidae) becomes difficult when it is based only on wing color patterns, a common practice in butterfly taxonomy. Difficulties in Mechanitis taxonomy are related to the widespread mimicry and polymorphism among species belonging to this genus. Species recognition and inventories of Mechanitis genus in geographic areas as the Andean region of Colombia are of particular interest and the use of more than one character for taxonomic identification is desirable. In this study, we included morphological, ecological, and mitochondrial DNA data to identify the occurring species in this region. Species of Mechanitis were studied from ecological, morphological, and molecular perspectives considering host plant identification, oviposition behavior, and life cycles under laboratory conditions. Immature morphology, patterns of wing color, and genital structures of adults were also studied. The genetic barcoding region of the cytochrome oxidase I mitochondrial gene was sequenced and used to verify the limits between species previously defined by the other characters and to validate its usefulness for species delimitation in this particular genus. The integrative approach combining independent datasets successfully allowed species identification as compared to the approach based on a single dataset. Three well-differentiated species were found in the studied region, Mechanitis menapis (Hewitson), Mechanitis polymnia (Linnaeus), and Mechanitis lysimnia (Fabricius). New valuable characters that could improve taxonomic identification in this genus are considered.

Structural and functional analysis of mouse Msx1 gene promoter: sequence conservation with human MSX1 promoter points at potential regulatory elements.

PubMed

Gonzalez, S M; Ferland, L H; Robert, B; Abdelhay, E

1998-06-01

Vertebrate Msx genes are related to one of the most divergent homeobox genes of Drosophila, the muscle segment homeobox (msh) gene, and are expressed in a well-defined pattern at sites of tissue interactions. This pattern of expression is conserved in vertebrates as diverse as quail, zebrafish, and mouse in a range of sites including neural crest, appendages, and craniofacial structures. In the present work, we performed structural and functional analyses in order to identify potential cis-acting elements that may be regulating Msx1 gene expression. To this end, a 4.9-kb segment of the 5'-flanking region was sequenced and analyzed for transcription-factor binding sites. Four regions showing a high concentration of these sites were identified. Transfection assays with fragments of regulatory sequences driving the expression of the bacterial lacZ reporter gene showed that a region of 4 kb upstream of the transcription start site contains positive and negative elements responsible for controlling gene expression. Interestingly, a fragment of 130 bp seems to contain the minimal elements necessary for gene expression, as its removal completely abolishes gene expression in cultured cells. These results are reinforced by comparison of this region with the human Msx1 gene promoter, which shows extensive conservation, including many consensus binding sites, suggesting a regulatory role for them.

Domain ordering of strained 5 ML SrTiO3 films on Si(001)

NASA Astrophysics Data System (ADS)

Ryan, P.; Wermeille, D.; Kim, J. W.; Woicik, J. C.; Hellberg, C. S.; Li, H.

2007-05-01

High resolution x-ray diffraction data indicate ordered square shaped coherent domains, ˜1200Å in length, coexisting with longer, ˜9500Å correlated regions in highly strained 5 ML SrTiO3 films grown on Si(001). These long range film structures are due to the Si substrate terraces defined by the surface step morphology. The silicon surface "step pattern" is comprised of an "intrinsic" terrace length from strain relaxation and a longer "extrinsic" interstep distance due to the surface miscut.

Chaotic terrain of Mars - A tectonic interpretation from Mariner 6 imagery

NASA Technical Reports Server (NTRS)

Wilson, R. C.; Harp, E. L.; Picard, M. D.; Ward, S. H.

1973-01-01

Sharp et al. (1971) define chaotic terrain as an irregular jumble of topographic forms covering a certain area within Pyrrhae Regio and adjacent regions centered at about 10 deg S., 35 deg W. This area is covered by Mariner 6 television imagery. An analysis of fracture patterns in the Martian surface from high-resolution Mariner 6 imagery suggests that the lineaments observed in both the chaotic terrain and the cratered plateau areas in Pyrrhae Regio are tectonic fractures resulting from stresses within the Martian crust.

Distributional patterns of living ungulates (Mammalia: Cetartiodactyla and Perissodactyla) of the Neotropical region, the South American transition zone and Andean region

NASA Astrophysics Data System (ADS)

Absolon, Bruno Araujo; Gallo, Valéria; Avilla, Leonardo S.

2016-11-01

To recognize the distributional patterns of living ungulates in the Neotropical region, the South American transition zone, and Andean region using the panbiogeographical method of track analysis, and to attempt to correlate these patterns with geological history. The distribution of 24 species of living ungulates (in the families Camelidae, Cervidae, Tapiridae and Tayassuidae) was studied by the panbiogeographical method of track analysis. It was performed using distributional data acquired from literature and databases of scientific institutions. Individual tracks were obtained for each species by plotting locality records on maps and connecting them by minimum-spanning trees. Generalized tracks were determined from the spatial overlap between individual tracks, indicating a common history. The intersection between generalized tracks defined a biogeographic node, implying that these locations are biogeographic composites resulting from different ancestral biotas coming into spatial contact, possibly at different geologic times. The superposition of the 24 individual tracks resulted in five generalized tracks (GTs): GT1, Mesoamerican/Choco (composed of Mazama pandora, Mazama temama, Odoicoileus virginianus and Tapirus bairdii); GT2, Northern Andes (Mazama rufina, Pudu mephistophiles and Tapirus pinchaque); GT3, Central Andes (Hippocamelus antisensis, Lama guanicoe, Mazama chunyi and Vicugna vicugna); GT4, Chilean Patagonia (Hippocamelus bisulcus and Pudu puda); and GT5, Chaco/Central west Brazil (Blastocerus dichotomus, Catagonus wagneri and Ozotocerus bezoarticus). The biogeographic node was found in the Northwestern Colombia. The geological events such as tectonism and volcanism that occurred through the Neogene and mainly in the Pleistocene caused fragmentation, diversification and endemism of biota. The biogeographic node in Colombia occurred within a zone of convergence. This node emphasized the complexity of the area and it contains biotic elements with different origins, which represent a special condition for the establishment of priority conservation areas.

Altered Functional Connectivity of Insular Subregions in Alzheimer’s Disease

PubMed Central

Liu, Xingyun; Chen, Xiaodan; Zheng, Weimin; Xia, Mingrui; Han, Ying; Song, Haiqing; Li, Kuncheng; He, Yong; Wang, Zhiqun

2018-01-01

Recent researches have demonstrated that the insula is the crucial hub of the human brain networks and most vulnerable region of Alzheimer’s disease (AD). However, little is known about the changes of functional connectivity of insular subregions in the AD patients. In this study, we collected resting-state functional magnetic resonance imaging (fMRI) data including 32 AD patients and 38 healthy controls (HCs). By defining three subregions of insula, we mapped whole-brain resting-state functional connectivity (RSFC) and identified several distinct RSFC patterns of the insular subregions: For positive connectivity, three cognitive-related RSFC patterns were identified within insula that suggest anterior-to-posterior functional subdivisions: (1) an dorsal anterior zone of the insula that exhibits RSFC with executive control network (ECN); (2) a ventral anterior zone of insula, exhibits functional connectivity with the salience network (SN); (3) a posterior zone along the insula exhibits functional connectivity with the sensorimotor network (SMN). In addition, we found significant negative connectivities between the each insular subregion and several special default mode network (DMN) regions. Compared with controls, the AD patients demonstrated distinct disruption of positive RSFCs in the different network (ECN and SMN), suggesting the impairment of the functional integrity. There were no differences of the positive RSFCs in the SN between the two groups. On the other hand, several DMN regions showed increased negative RSFCs to the sub-region of insula in the AD patients, indicating compensatory plasticity. Furthermore, these abnormal insular subregions RSFCs are closely correlated with cognitive performances in the AD patients. Our findings suggested that different insular subregions presented distinct RSFC patterns with various functional networks, which are differently affected in the AD patients. PMID:29695961

Altered Functional Connectivity of Insular Subregions in Alzheimer's Disease.

PubMed

Liu, Xingyun; Chen, Xiaodan; Zheng, Weimin; Xia, Mingrui; Han, Ying; Song, Haiqing; Li, Kuncheng; He, Yong; Wang, Zhiqun

2018-01-01

Recent researches have demonstrated that the insula is the crucial hub of the human brain networks and most vulnerable region of Alzheimer's disease (AD). However, little is known about the changes of functional connectivity of insular subregions in the AD patients. In this study, we collected resting-state functional magnetic resonance imaging (fMRI) data including 32 AD patients and 38 healthy controls (HCs). By defining three subregions of insula, we mapped whole-brain resting-state functional connectivity (RSFC) and identified several distinct RSFC patterns of the insular subregions: For positive connectivity, three cognitive-related RSFC patterns were identified within insula that suggest anterior-to-posterior functional subdivisions: (1) an dorsal anterior zone of the insula that exhibits RSFC with executive control network (ECN); (2) a ventral anterior zone of insula, exhibits functional connectivity with the salience network (SN); (3) a posterior zone along the insula exhibits functional connectivity with the sensorimotor network (SMN). In addition, we found significant negative connectivities between the each insular subregion and several special default mode network (DMN) regions. Compared with controls, the AD patients demonstrated distinct disruption of positive RSFCs in the different network (ECN and SMN), suggesting the impairment of the functional integrity. There were no differences of the positive RSFCs in the SN between the two groups. On the other hand, several DMN regions showed increased negative RSFCs to the sub-region of insula in the AD patients, indicating compensatory plasticity. Furthermore, these abnormal insular subregions RSFCs are closely correlated with cognitive performances in the AD patients. Our findings suggested that different insular subregions presented distinct RSFC patterns with various functional networks, which are differently affected in the AD patients.

C-Type Lectin Receptor MCL Facilitates Mincle Expression and Signaling through Complex Formation.

PubMed

Miyake, Yasunobu; Masatsugu, Oh-hora; Yamasaki, Sho

2015-06-01

C-type lectin receptors expressed in APCs are recently defined pattern recognition receptors that play a crucial role in immune responses against pathogen-associated molecular patterns. Among pathogen-associated molecular patterns, cord factor (trehalose-6,6'-dimycolate [TDM]) is the most potent immunostimulatory component of the mycobacterial cell wall. Two C-type lectin receptors, macrophage-inducible C-type lectin (Mincle) and macrophage C-type lectin (MCL), are required for immune responses against TDM. Previous studies indicate that MCL is required for TDM-induced Mincle expression. However, the mechanism by which MCL induces Mincle expression has not been fully understood. In this study, we demonstrate that MCL interacts with Mincle to promote its surface expression. After LPS or zymosan stimulation, MCL-deficient bone marrow-derived dendritic cells (BMDCs) had a lower level of Mincle protein expression, although mRNA expression was comparable with wild-type BMDCs. Meanwhile, BMDCs from MCL transgenic mice showed an enhanced level of Mincle expression on the cell surface. MCL was associated with Mincle through the stalk region and this region was necessary and sufficient for the enhancement of Mincle expression. This interaction appeared to be mediated by the hydrophobic repeat of MCL, as substitution of four hydrophobic residues within the stalk region with serine (MCL(4S)) abolished the function to enhance the surface expression of Mincle. MCL(4S) mutant failed to restore the defective TDM responses in MCL-deficient BMDCs. These results suggest that MCL positively regulates Mincle expression through protein-protein interaction via its stalk region, thereby magnifying Mincle-mediated signaling. Copyright © 2015 by The American Association of Immunologists, Inc.

Squamous Cell Carcinoma of the Anal Canal: Patterns and Predictors of Failure and Implications for Intensity-Modulated Radiation Treatment Planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wright, Jean L., E-mail: jwright3@med.miami.ed; Patil, Sujata M.; Temple, Larissa K.F.

2010-11-15

Purpose: Intensity-modulated radiation treatment (IMRT) is increasingly used in the treatment of squamous cell carcinoma of the anal canal (SCCAC). Prevention of locoregional failure (LRF) using IMRT requires appropriate clinical target volume (CTV) definition. To better define the CTV for IMRT, we evaluated patterns and predictors of LRF in SCCAC patients given conventional radiation treatment. Methods and Materials: We reviewed records of 180 SCCAC patients treated with conventional radiation with or without chemotherapy at our institution between January 1990 and March 2007. All patients received radiation; the median primary tumor dose was 45 Gy. A total of 173 patients alsomore » received mitomycin-based chemotherapy. Results: Median follow-up was 40 months. Actuarial 3-year colostomy-free survival was 89% and overall survival (OS) 88%. Actuarial 3-year LRF was 23%. A total of 45 patients had LRF, with 35 (78%) occurring locally in the primary site (25 local only, 10 local and regional); however, 20 (44%) had regional components of failure within the pelvis or inguinal nodes (10 regional only, 10 local and regional). Cumulative sites of LRF (patients may have one or more site of failure) were as follows: primary, 35; inguinal, 8; external perianal, 5; common iliac, 4; presacral, 3; distal rectum, 2; external iliac, 2; and internal iliac, 2. All patients with common iliac failure had cT3 or N+ disease. Conclusions: The observed patterns of failure support inclusion of the inguinal and all pelvic nodal groups in the CTV for IMRT. In patients with advanced tumor or nodal stage, common iliac nodes should also be included in the CTV.« less

Dietary availability patterns of the Brazilian macro-regions.

PubMed

Nascimento, Sileia; Barbosa, Flávia S; Sichieri, Rosely; Pereira, Rosangela A

2011-07-28

Epidemiological studies have raised concerns about the role of dietary patterns on the risk of chronic diseases and also in the formulation of better informed nutrition policies. The development of a dietary availability patterns according to geographic regions in Brazil. The 2002-2003 Brazilian Household Budget Survey was conducted in 48,470 households. Dietary availability patterns were identified by Principal Component Analysis using as a unit of analysis the survey's Primary Sampling Units (PSUs) and purchased amounts for 21 food groups. Each of the extracted dietary availability patterns was regressed on socioeconomics categories. There were no differences in dietary availability patterns between urban and rural areas. In all regions, a rice and beans pattern was identified. This pattern explained 15% to 28% of the variance dependent on the region of the country. In South, Southeast and Midwest regions, a mixed pattern including at least 10 food groups explaining 8% to 16% of the variance. In the North region (Amazon forest included) the first pattern was based on fish and nuts and then it was designed as regional pattern. In multiple linear regression the rice and beans pattern was associated with the presence of adolescents in the households, except for North region, whereas the presence of adolescents was associated with the Regional pattern. A mixed patterns were associated with a higher income and education (p < 0.05), except in the South region. The rice and beans and regional dietary availability patterns, both considered healthy eating patterns are still important in the country. Brazil has taken many actions to improve nutrition as part of their public health policies, the data of the Household Budget Survey could help to recognize the different food choices in the large regions of the country.

Head patterning and Hox gene expression in an onychophoran and its implications for the arthropod head problem.

PubMed

Eriksson, Bo Joakim; Tait, Noel N; Budd, Graham E; Janssen, Ralf; Akam, Michael

2010-09-01

The arthropod head problem has puzzled zoologists for more than a century. The head of adult arthropods is a complex structure resulting from the modification, fusion and migration of an uncertain number of segments. In contrast, onychophorans, which are the probable sister group to the arthropods, have a rather simple head comprising three segments that are well defined during development, and give rise to the adult head with three pairs of appendages specialised for sensory and food capture/manipulative purposes. Based on the expression pattern of the anterior Hox genes labial, proboscipedia, Hox3 and Deformed, we show that the third of these onychophoran segments, bearing the slime papillae, can be correlated to the tritocerebrum, the most anterior Hox-expressing arthropod segment. This implies that both the onychophoran antennae and jaws are derived from a more anterior, Hox-free region corresponding to the proto and deutocerebrum of arthropods. Our data provide molecular support for the proposal that the onychophoran head possesses a well-developed appendage that corresponds to the anterior, apparently appendage-less region of the arthropod head.

A regulatory toolbox of MiniPromoters to drive selective expression in the brain

PubMed Central

Portales-Casamar, Elodie; Swanson, Douglas J.; Liu, Li; de Leeuw, Charles N.; Banks, Kathleen G.; Ho Sui, Shannan J.; Fulton, Debra L.; Ali, Johar; Amirabbasi, Mahsa; Arenillas, David J.; Babyak, Nazar; Black, Sonia F.; Bonaguro, Russell J.; Brauer, Erich; Candido, Tara R.; Castellarin, Mauro; Chen, Jing; Chen, Ying; Cheng, Jason C. Y.; Chopra, Vik; Docking, T. Roderick; Dreolini, Lisa; D'Souza, Cletus A.; Flynn, Erin K.; Glenn, Randy; Hatakka, Kristi; Hearty, Taryn G.; Imanian, Behzad; Jiang, Steven; Khorasan-zadeh, Shadi; Komljenovic, Ivana; Laprise, Stéphanie; Liao, Nancy Y.; Lim, Jonathan S.; Lithwick, Stuart; Liu, Flora; Liu, Jun; Lu, Meifen; McConechy, Melissa; McLeod, Andrea J.; Milisavljevic, Marko; Mis, Jacek; O'Connor, Katie; Palma, Betty; Palmquist, Diana L.; Schmouth, Jean-François; Swanson, Magdalena I.; Tam, Bonny; Ticoll, Amy; Turner, Jenna L.; Varhol, Richard; Vermeulen, Jenny; Watkins, Russell F.; Wilson, Gary; Wong, Bibiana K. Y.; Wong, Siaw H.; Wong, Tony Y. T.; Yang, George S.; Ypsilanti, Athena R.; Jones, Steven J. M.; Holt, Robert A.; Goldowitz, Daniel; Wasserman, Wyeth W.; Simpson, Elizabeth M.

2010-01-01

The Pleiades Promoter Project integrates genomewide bioinformatics with large-scale knockin mouse production and histological examination of expression patterns to develop MiniPromoters and related tools designed to study and treat the brain by directed gene expression. Genes with brain expression patterns of interest are subjected to bioinformatic analysis to delineate candidate regulatory regions, which are then incorporated into a panel of compact human MiniPromoters to drive expression to brain regions and cell types of interest. Using single-copy, homologous-recombination “knockins” in embryonic stem cells, each MiniPromoter reporter is integrated immediately 5′ of the Hprt locus in the mouse genome. MiniPromoter expression profiles are characterized in differentiation assays of the transgenic cells or in mouse brains following transgenic mouse production. Histological examination of adult brains, eyes, and spinal cords for reporter gene activity is coupled to costaining with cell-type–specific markers to define expression. The publicly available Pleiades MiniPromoter Project is a key resource to facilitate research on brain development and therapies. PMID:20807748

Peat landforms along the Albany River, northern Ontario. An ecological study of peat landforms in Canada and Alaska

NASA Technical Reports Server (NTRS)

Glaser, P. H.

1985-01-01

During the summer of 1985 a field investigation was started in the Hudson Bay lowland region of northern Ontario, which represents the largest expanse of peatland in North America and is an important sink in the global carbon cycle. A key area in the lowlands is situated along the Albany River near the confluence of the Chepay River. Here the striking vegetation-landforms are transitional between those found on the bed of Glacial Lake Agassiz in northern Minnesota and southern Manitoba and the more northern peatlands in the Hudson Bay lowland region. In peatland studies elsewhere the landform patterns have been used not only to classify different peatland types but also as an indicator of potential developmetnal trends. The study area is generally defined by that covered by the TM scene E-40062-15532 taken on Sept. 16, 1982. The purpose of the field work is to acquire sufficent information to interpret the TM imagery and test various hypotheses on peatland development on the gasis of the pattern transitions.

Thermal anomaly mapping from night MODIS imagery of USA, a tool for environmental assessment.

PubMed

Miliaresis, George Ch

2013-02-01

A method is presented for elevation, latitude and longitude decorrelation stretch of multi-temporal MODIS MYD11C3 imagery (monthly average night land surface temperature (LST) across USA and Mexico). Multiple linear regression analysis of principal components images (PCAs) quantifies the variance explained by elevation (H), latitude (LAT), and longitude (LON). The multi-temporal LST imagery is reconstructed from the residual images and selected PCAs by taking into account the portion of variance that is not related to H, LAT, LON. The reconstructed imagery presents the magnitude the standardized LST value per pixel deviates from the H, LAT, LON predicted. LST anomaly is defined as a region that presents either positive or negative reconstructed LST value. The environmental assessment of USA indicated that only for the 25 % of the study area (Mississippi drainage basin), the LST is predicted by the H, LAT, LON. Regions with milled climatic pattern were identified in the West Coast while the coldest climatic pattern is observed for Mid USA. Positive season invariant LST anomalies are identified in SW (Arizona, Sierra Nevada, etc.) and NE USA.

Reconstructing spatial and temporal patterns of paleoglaciation across Central Asia

NASA Astrophysics Data System (ADS)

Stroeven, Arjen P.

2014-05-01

Understanding the behaviour of mountain glaciers and ice caps, the evolution of mountain landscapes, and testing global climate models all require well-constrained information on past spatial and temporal patterns of glacier change. Particularly important are transitional regions that have high spatial and temporal variation in glacier activity and that can provide a sensitive record of past climate change. Central Asia is an extreme continental location with glaciers that have responded sensitively to variations in major regional climate systems. As an international team, we are reconstructing glacial histories of several areas of the Tibetan Plateau as well as along the Tian Shan, Altai and Kunlun Mountains. Building on previous work, we are using remote sensing-based geomorphological mapping augmented with field observations to map out glacial landforms and the maximum distributions of erratics. We then use cosmogenic nuclide Be-10 and Al-26, optically stimulated luminescence, and electron spin resonance dating of moraines and other landforms to compare dating techniques and to constrain the ages of defined extents of paleo-glaciers and ice caps. Comparing consistently dated glacial histories across central Asia provides an opportunity to examine shifts in the dominance patterns of climate systems over time in the region. Results to date show significant variations in the timing and extent of glaciation, including areas in the southeast Tibetan Plateau and Tian Shan with extensive valley and small polythermal ice cap glaciation during the global last glacial maximum in contrast to areas in central and northeast Tibetan Plateau that had very limited valley glacier expansion then. Initial numerical modelling attempting to simulate mapped and dated paleoglacial extents indicates that relatively limited cooling is sufficient to produce observed past expansions of glaciers across the Tibetan Plateau, and predicts complex basal thermal regimes in some locations that match patterns of past glacial erosion inferred from landform patterns and ages. Future modelling will examine glacier behaviour along major mountain ranges across central Asia.

Phytoplankton blooms in estuarine and coastal waters: Seasonal patterns and key species

USGS Publications Warehouse

Carstensen, Jacob; Klais, Riina; Cloern, James E.

2015-01-01

Phytoplankton blooms are dynamic phenomena of great importance to the functioning of estuarine and coastal ecosystems. We analysed a unique (large) collection of phytoplankton monitoring data covering 86 coastal sites distributed over eight regions in North America and Europe, with the aim of investigating common patterns in the seasonal timing and species composition of the blooms. The spring bloom was the most common seasonal pattern across all regions, typically occurring early (February–March) at lower latitudes and later (April–May) at higher latitudes. Bloom frequency, defined as the probability of unusually high biomass, ranged from 5 to 35% between sites and followed no consistent patterns across gradients of latitude, temperature, salinity, water depth, stratification, tidal amplitude or nutrient concentrations. Blooms were mostly dominated by a single species, typically diatoms (58% of the blooms) and dinoflagellates (19%). Diatom-dominated spring blooms were a common feature in most systems, although dinoflagellate spring blooms were also observed in the Baltic Sea. Blooms dominated by chlorophytes and cyanobacteria were only common in low salinity waters and occurred mostly at higher temperatures. Key bloom species across the eight regions included the diatoms Cerataulina pelagica and Dactyliosolen fragilissimus and dinoflagellates Heterocapsa triquetra and Prorocentrum cordatum. Other frequent bloom-forming taxa were diatom genera Chaetoceros, Coscinodiscus, Skeletonema, and Thalassiosira. Our meta-analysis shows that these 86 estuarine-coastal sites function as diatom-producing systems, the timing of that production varies widely, and that bloom frequency is not associated with environmental factors measured in monitoring programs. We end with a perspective on the limitations of conclusions derived from meta-analyses of phytoplankton time series, and the grand challenges remaining to understand the wide range of bloom patterns and processes that select species as bloom dominants in coastal waters.

Environmental Complexity and Biodiversity: The Multi-Layered Evolutionary History of a Log-Dwelling Velvet Worm in Montane Temperate Australia

PubMed Central

Garrick, Ryan C.; Gardner, Michael G.; Tait, Noel N.; Briscoe, David A.; Rowell, David M.; Sunnucks, Paul

2013-01-01

Phylogeographic studies provide a framework for understanding the importance of intrinsic versus extrinsic factors in shaping patterns of biodiversity through identifying past and present microevolutionary processes that contributed to lineage divergence. Here we investigate population structure and diversity of the Onychophoran (velvet worm) Euperipatoides rowelli in southeastern Australian montane forests that were not subject to Pleistocene glaciations, and thus likely retained more forest cover than systems under glaciation. Over a ~100 km transect of structurally-connected forest, we found marked nuclear and mitochondrial (mt) DNA genetic structuring, with spatially-localised groups. Patterns from mtDNA and nuclear data broadly corresponded with previously defined geographic regions, consistent with repeated isolation in refuges during Pleistocene climatic cycling. Nevertheless, some E. rowelli genetic contact zones were displaced relative to hypothesized influential landscape structures, implying more recent processes overlying impacts of past environmental history. Major impacts at different timescales were seen in the phylogenetic relationships among mtDNA sequences, which matched geographic relationships and nuclear data only at recent timescales, indicating historical gene flow and/or incomplete lineage sorting. Five major E. rowelli phylogeographic groups were identified, showing substantial but incomplete reproductive isolation despite continuous habitat. Regional distinctiveness, in the face of lineages abutting within forest habitat, could indicate pre- and/or postzygotic gene flow limitation. A potentially functional phenotypic character, colour pattern variation, reflected the geographic patterns in the molecular data. Spatial-genetic patterns broadly match those in previously-studied, co-occurring low-mobility organisms, despite a variety of life histories. We suggest that for E. rowelli, the complex topography and history of the region has led to interplay among limited dispersal ability, historical responses to environmental change, local adaptation, and some resistance to free admixture at geographic secondary contact, leading to strong genetic structuring at fine spatial scale. PMID:24358365

Automated mapping of burned areas in semi-arid ecosystems using modis time-series imagery

NASA Astrophysics Data System (ADS)

Hardtke, L. A.; Blanco, P. D.; del Valle, H. F.; Metternicht, G. I.; Sione, W. F.

2015-04-01

Understanding spatial and temporal patterns of burned areas at regional scales, provides a long-term perspective of fire processes and its effects on ecosystems and vegetation recovery patterns, and it is a key factor to design prevention and post-fire restoration plans and strategies. Standard satellite burned area and active fire products derived from the 500-m MODIS and SPOT are avail - able to this end. However, prior research caution on the use of these global-scale products for regional and sub-regional applica - tions. Consequently, we propose a novel algorithm for automated identification and mapping of burned areas at regional scale in semi-arid shrublands. The algorithm uses a set of the Normalized Burned Ratio Index products derived from MODIS time series; using a two-phased cycle, it firstly detects potentially burned pixels while keeping a low commission error (false detection of burned areas), and subsequently labels them as seed patches. Region growing image segmentation algorithms are applied to the seed patches in the second-phase, to define the perimeter of fire affected areas while decreasing omission errors (missing real burned areas). Independently-derived Landsat ETM+ burned-area reference data was used for validation purposes. The correlation between the size of burnt areas detected by the global fire products and independently-derived Landsat reference data ranged from R2 = 0.01 - 0.28, while our algorithm performed showed a stronger correlation coefficient (R2 = 0.96). Our findings confirm prior research calling for caution when using the global fire products locally or regionally.

Fault Slip and GPS Velocities Across the Shan Plateau Define a Curved Southwestward Crustal Motion Around the Eastern Himalayan Syntaxis

NASA Astrophysics Data System (ADS)

Shi, Xuhua; Wang, Yu; Sieh, Kerry; Weldon, Ray; Feng, Lujia; Chan, Chung-Han; Liu-Zeng, Jing

2018-03-01

Characterizing the 700 km wide system of active faults on the Shan Plateau, southeast of the eastern Himalayan syntaxis, is critical to understanding the geodynamics and seismic hazard of the large region that straddles neighboring China, Myanmar, Thailand, Laos, and Vietnam. Here we evaluate the fault styles and slip rates over multi-timescales, reanalyze previously published short-term Global Positioning System (GPS) velocities, and evaluate slip-rate gradients to interpret the regional kinematics and geodynamics that drive the crustal motion. Relative to the Sunda plate, GPS velocities across the Shan Plateau define a broad arcuate tongue-like crustal motion with a progressively northwestward increase in sinistral shear over a distance of 700 km followed by a decrease over the final 100 km to the syntaxis. The cumulative GPS slip rate across the entire sinistral-slip fault system on the Shan Plateau is 12 mm/year. Our observations of the fault geometry, slip rates, and arcuate southwesterly directed tongue-like patterns of GPS velocities across the region suggest that the fault kinematics is characterized by a regional southwestward distributed shear across the Shan Plateau, compared to more block-like rotation and indentation north of the Red River fault. The fault geometry, kinematics, and regional GPS velocities are difficult to reconcile with regional bookshelf faulting between the Red River and Sagaing faults or localized lower crustal channel flows beneath this region. The crustal motion and fault kinematics can be driven by a combination of basal traction of a clockwise, southwestward asthenospheric flow around the eastern Himalayan syntaxis and gravitation or shear-driven indentation from north of the Shan Plateau.

Earth Science Studies in Support of Public Policy Development and Land Stewardship - Headwaters Province, Idaho and Montana

USGS Publications Warehouse

U.S. Geological Survey Headwaters Province Project Team Edited by Lund, Karen

2007-01-01

The USGS Headwaters Province project in western Montana and northern and central Idaho was designed to provide geoscience data and interpretations to Federal Land Management Agencies and to respond to specific concerns of USDA Forest Service Regions 1 and 4. The project has emphasized development of digital geoscience data, GIS analyses, topical studies, and new geologic interpretations. Studies were designed to more completely map lithologic units and determine controls of deformation, magmatism, and mineralizing processes. Topical studies of geologic basement control on these processes include study of regional metallogenic patterns and their relation to the composition and architecture of underlying, unexposed basement; timing of igneous and hydrothermal systems, to identify regionally important metallogenic magmatism; and the geologic setting of Proterozoic strata, to better understand how their sedimentary basins developed and to define the origin of sediment-hosted mineral deposits. Interrelated products of the project are at complementary scales.

Contribution to the Study of Regional Magnetization of Satellite Magnetic Measurement: Magsat, Orsted, and Champ (with Gravity Field)

NASA Technical Reports Server (NTRS)

Taylor, Patrick T.

2004-01-01

A discussion of and introduction to satellite-altitude geopotential field studies and their interpretation with emphasis on results from metalliferous regions will be given. The magnetic and gravimetric measurements from satellite altitudes show heterogeneity in deeper parts of the lithosphere. These patterns of magnetic anomalies do not only reveal the largest iron ore deposits such as Kiruna, Sweden, Kursk, Russia, and Banugi, Central African Republic but also linear features indicating structural discontinuities. Changes of magnetic amplitude of these patterns are caused by intersecting transverse fractures localizing magmatism and concentration of metals. In addition satellite altitude data are related to variations in crustal thickness and heat flow. Deep-rooted structural discontinuities, defined by combination of geological and geophysical criteria, with spacing of several hundred kilometers, reveal a quite uniform pattern in the deeper parts of the lithosphere. As these structures provide favorable pathways for the ascent of heat, magmas and ore-forming fluids, their recognition is of crucial importance and can be used in the compilation of a new type of mineral prognosis map. An example from Europe includes a pattern of east west trending structural discontinuities or belts and their junction with the NW-trending Tornqvist-Teisseyre Line. The Upper Silesian-Cracovian Zn-Pb district occurs along one of the latitudinal belts. Leslaw Teper of the University of Silesia has been invited to show the fractures in crystalline basement beneath the sediments hosting the Zn-Pb ores.

FUNCTIONAL NETWORK ARCHITECTURE OF READING-RELATED REGIONS ACROSS DEVELOPMENT

PubMed Central

Vogel, Alecia C.; Church, Jessica A.; Power, Jonathan D.; Miezin, Fran M.; Petersen, Steven E.; Schlaggar, Bradley L.

2013-01-01

Reading requires coordinated neural processing across a large number of brain regions. Studying relationships between reading-related regions informs the specificity of information processing performed in each region. Here, regions of interest were defined from a meta-analysis of reading studies, including a developmental study. Relationships between regions were defined as temporal correlations in spontaneous fMRI signal; i.e., resting state functional connectivity MRI (RSFC). Graph theory based network analysis defined the community structure of the “reading-related” regions. Regions sorted into previously defined communities, such as the fronto-parietal and cingulo-opercular control networks, and the default mode network. This structure was similar in children, and no apparent “reading” community was defined in any age group. These results argue against regions, or sets of regions, being specific or preferential for reading, instead indicating that regions used in reading are also used in a number of other tasks. PMID:23506969

Analysis of Stakeholder-Defined Needs in Northeast U.S. Coastal Communities to Determine Gaps in Research Informing Coastal Resilience Planning

NASA Astrophysics Data System (ADS)

Molino, G. D.; Kenney, M. A.; Sutton-Grier, A.; Penn, K.

2017-12-01

The impacts of climate change on our coastlines are increasing pressure on communities, ecosystems, infrastructure, and state-to-local economies in the northeastern United States (U.S.). As a result of current or imminent risk of acute and chronic hazards, local, state and regional entities have taken steps to identify and address vulnerabilities to climate change. Decisions to increase coastal infrastructure resilience and grey, green, and cultural infrastructure solutions requires physical, natural, and social science that is useful for decision-making and effective science translation mechanisms. Despite the desire to conduct or fund science that meets the needs of communities, there has been no comprehensive analysis to determine stakeholder-defined research needs. To address this gap, this study conducts a stakeholder needs analysis in northeast U.S. coastal communities to determine gaps in information and translation processes supporting coastal resilience planning. Documents were sourced from local, state, and regional organizations in both the public and private sectors, using the northeast region defined by the third National Climate Assessment. Modeled after Dilling et al. (2015), a deductive coding schema was developed that categorized documents using specific search terms such as "Location and condition of infrastructure" and "Proactive planning". A qualitative document analysis was then executed using NVivo to formally identify patterns and themes present in stakeholder surveys, workshop proceedings, and reports. Initial stakeholder priorities centered around incorporation of climate science into planning and decision making regarding vulnerabilities of infrastructure, enhanced emergency planning and response, and communication of key information.

Continuous High Frequency Activity: A peculiar SEEG pattern related to specific brain regions

PubMed Central

Melani, Federico; Zelmann, Rina; Mari, Francesco; Gotman, Jean

2015-01-01

Objective While visually marking the high frequency oscillations in the stereo-EEG of epileptic patients, we observed a continuous/semicontinuous activity in the ripple band (80–250 Hz), which we defined continuous High Frequency Activity (HFA). We aim to analyze in all brain regions the occurrence and significance of this particular pattern. Methods Twenty patients implanted in mesial temporal and neocortical areas were studied. One minute of slow-wave sleep was reviewed. The background was classified as continuous/semicontinuous, irregular, or sporadic based on the duration of the fast oscillations. Each channel was classified as inside/outside the seizure onset zone (SOZ) or a lesion. Results The continuous/semicontinuous HFA occurred in 54 of the 790 channels analyzed, with a clearly higher prevalence in hippocampus and occipital lobe. No correlation was found with the SOZ or lesions. In the occipital lobe the continuous/semicontinuous HFA was present independently of whether eyes were open or closed. Conclusions We describe what appears to be a new physiological High Frequency Activity, independent of epileptogenicity, present almost exclusively in the hippocampus and occipital cortex but independent of the alpha rhythm. Significance The continuous HFA may be an intrinsic characteristic of specific brain regions, reflecting a particular type of physiological neuronal activity. PMID:23768436

Three-dimensional ultrastructural analyses of anterior pituitary gland expose spatial relationships between endocrine cell secretory granule localization and capillary distribution.

PubMed

Yoshitomi, Munetake; Ohta, Keisuke; Kanazawa, Tomonoshin; Togo, Akinobu; Hirashima, Shingo; Uemura, Kei-Ichiro; Okayama, Satoko; Morioka, Motohiro; Nakamura, Kei-Ichiro

2016-10-31

Endocrine and endothelial cells of the anterior pituitary gland frequently make close appositions or contacts, and the secretory granules of each endocrine cell tend to accumulate at the perivascular regions, which is generally considered to facilitate secretory functions of these cells. However, three-dimensional relationships between the localization pattern of secretory granules and blood vessels are not fully understood. To define and characterize these spatial relationships, we used scanning electron microscopy (SEM) three-dimensional reconstruction method based on focused ion-beam slicing and scanning electron microscopy (FIB/SEM). Full three-dimensional cellular architectures of the anterior pituitary tissue at ultrastructural resolution revealed that about 70% of endocrine cells were in apposition to the endothelial cells, while almost 30% of endocrine cells were entirely isolated from perivascular space in the tissue. Our three-dimensional analyses also visualized the distribution pattern of secretory granules in individual endocrine cells, showing an accumulation of secretory granules in regions in close apposition to the blood vessels in many cases. However, secretory granules in cells isolated from the perivascular region tended to distribute uniformly in the cytoplasm of these cells. These data suggest that the cellular interactions between the endocrine and endothelial cells promote an uneven cytoplasmic distribution of the secretory granules.

4-dimensional functional profiling in the convulsant-treated larval zebrafish brain.

PubMed

Winter, Matthew J; Windell, Dylan; Metz, Jeremy; Matthews, Peter; Pinion, Joe; Brown, Jonathan T; Hetheridge, Malcolm J; Ball, Jonathan S; Owen, Stewart F; Redfern, Will S; Moger, Julian; Randall, Andrew D; Tyler, Charles R

2017-07-26

Functional neuroimaging, using genetically-encoded Ca 2+ sensors in larval zebrafish, offers a powerful combination of high spatiotemporal resolution and higher vertebrate relevance for quantitative neuropharmacological profiling. Here we use zebrafish larvae with pan-neuronal expression of GCaMP6s, combined with light sheet microscopy and a novel image processing pipeline, for the 4D profiling of chemoconvulsant action in multiple brain regions. In untreated larvae, regions associated with autonomic functionality, sensory processing and stress-responsiveness, consistently exhibited elevated spontaneous activity. The application of drugs targeting different convulsant mechanisms (4-Aminopyridine, Pentylenetetrazole, Pilocarpine and Strychnine) resulted in distinct spatiotemporal patterns of activity. These activity patterns showed some interesting parallels with what is known of the distribution of their respective molecular targets, but crucially also revealed system-wide neural circuit responses to stimulation or suppression. Drug concentration-response curves of neural activity were identified in a number of anatomically-defined zebrafish brain regions, and in vivo larval electrophysiology, also conducted in 4dpf larvae, provided additional measures of neural activity. Our quantification of network-wide chemoconvulsant drug activity in the whole zebrafish brain illustrates the power of this approach for neuropharmacological profiling in applications ranging from accelerating studies of drug safety and efficacy, to identifying pharmacologically-altered networks in zebrafish models of human neurological disorders.

Posttraumatic stress disorder among refugees: Measurement invariance of Harvard Trauma Questionnaire scores across global regions and response patterns.

PubMed

Rasmussen, Andrew; Verkuilen, Jay; Ho, Emily; Fan, Yuyu

2015-12-01

Despite the central role of posttraumatic stress disorder (PTSD) in international humanitarian aid work, there has been little examination of the measurement invariance of PTSD measures across culturally defined refugee subgroups. This leaves mental health workers in disaster settings with little to support inferences made using the results of standard clinical assessment tools, such as the severity of symptoms and prevalence rates. We examined measurement invariance in scores from the most widely used PTSD measure in refugee populations, the Harvard Trauma Questionnaire (HTQ; Mollica et al., 1992), in a multinational and multilingual sample of asylum seekers from 81 countries of origin in 11 global regions. Clustering HTQ responses to justify grouping regional groups by response patterns resulted in 3 groups for testing measurement invariance: West Africans, Himalayans, and all others. Comparing log-likelihood ratios showed that while configural invariance seemed to hold, metric and scalar invariance did not. These findings call into question the common practice of using standard cut-off scores on PTSD measures across culturally dissimilar refugee populations. In addition, high correlation between factors suggests that the construct validity of scores from North American and European measures of PTSD may not hold globally. (c) 2015 APA, all rights reserved).

Stable Patterns of CENH3 Occupancy Through Maize Lineages Containing Genetically Similar Centromeres

PubMed Central

Gent, Jonathan I.; Wang, Kai; Jiang, Jiming; Dawe, R. Kelly

2015-01-01

While the approximate chromosomal position of centromeres has been identified in many species, little is known about the dynamics and diversity of centromere positions within species. Multiple lines of evidence indicate that DNA sequence has little or no impact in specifying centromeres in maize and in most multicellular organisms. Given that epigenetically defined boundaries are expected to be dynamic, we hypothesized that centromere positions would change rapidly over time, which would result in a diversity of centromere positions in isolated populations. To test this hypothesis, we used CENP-A/cenH3 (CENH3 in maize) chromatin immunoprecipitation to define centromeres in breeding pedigrees that included the B73 inbred as a common parent. While we found a diversity of CENH3 profiles for centromeres with divergent sequences that were not inherited from B73, the CENH3 profiles from centromeres that were inherited from B73 were indistinguishable from each other. We propose that specific genetic elements in centromeric regions favor or inhibit CENH3 accumulation, leading to reproducible patterns of CENH3 occupancy. These data also indicate that dramatic shifts in centromere position normally originate from accumulated or large-scale genetic changes rather than from epigenetic positional drift. PMID:26063660

HRTEMFringeAnalyzer a free python module for an automated analysis of fringe pattern in transmission electron micrographs.

PubMed

Alxneit, Ivo

2018-03-30

A python module (HRTEMFringeAnalyzer) is reported to evaluate the local crystallinity of samples from high-resolution transmission electron microscopy images in a mostly automated fashion. The user only selects the size of a square analyser window and a step size which translates the window in the micrograph. Together they define the resolution of the results obtained. Regions where fringe patterns are visible are identified and their lattice spacing d and direction ϕ as well as the corresponding mean errors σ determined. 1/σd is proportional to the coherence length of the structure, whereas σφ is a measure of how well the direction of the fringes is defined. Maps of these four indicators are computed. The performance of the program is demonstrated on two very different samples: ill-crystalline carbon deposits on a coked Ni/LFNO (reduced LaFe 0.8 Ni 0.2 O3±δ) catalyst and well-crystallized nanoparticles of zinc doped ceria. In the latter case, the automatic segmentation of large aggregates into individual crystalline domains is achieved by ϕ maps. © 2018 The Authors Journal of Microscopy © 2018 Royal Microscopical Society.

White Matter Connectivity of the Thalamus Delineates the Functional Architecture of Competing Thalamocortical Systems

PubMed Central

O'Muircheartaigh, Jonathan; Keller, Simon S.; Barker, Gareth J.; Richardson, Mark P.

2015-01-01

There is an increasing awareness of the involvement of thalamic connectivity on higher level cortical functioning in the human brain. This is reflected by the influence of thalamic stimulation on cortical activity and behavior as well as apparently cortical lesion syndromes occurring as a function of small thalamic insults. Here, we attempt to noninvasively test the correspondence of structural and functional connectivity of the human thalamus using diffusion-weighted and resting-state functional MRI. Using a large sample of 102 adults, we apply tensor independent component analysis to diffusion MRI tractography data to blindly parcellate bilateral thalamus according to diffusion tractography-defined structural connectivity. Using resting-state functional MRI collected in the same subjects, we show that the resulting structurally defined thalamic regions map to spatially distinct, and anatomically predictable, whole-brain functional networks in the same subjects. Although there was significant variability in the functional connectivity patterns, the resulting 51 structural and functional patterns could broadly be reduced to a subset of 7 similar core network types. These networks were distinct from typical cortical resting-state networks. Importantly, these networks were distributed across the brain and, in a subset, map extremely well to known thalamocortico-basal-ganglial loops. PMID:25899706

Ground-state coding in partially connected neural networks

NASA Technical Reports Server (NTRS)

Baram, Yoram

1989-01-01

Patterns over (-1,0,1) define, by their outer products, partially connected neural networks, consisting of internally strongly connected, externally weakly connected subnetworks. The connectivity patterns may have highly organized structures, such as lattices and fractal trees or nests. Subpatterns over (-1,1) define the subcodes stored in the subnetwork, that agree in their common bits. It is first shown that the code words are locally stable stares of the network, provided that each of the subcodes consists of mutually orthogonal words or of, at most, two words. Then it is shown that if each of the subcodes consists of two orthogonal words, the code words are the unique ground states (absolute minima) of the Hamiltonian associated with the network. The regions of attraction associated with the code words are shown to grow with the number of subnetworks sharing each of the neurons. Depending on the particular network architecture, the code sizes of partially connected networks can be vastly greater than those of fully connected ones and their error correction capabilities can be significantly greater than those of the disconnected subnetworks. The codes associated with lattice-structured and hierarchical networks are discussed in some detail.

Quantifying the impact of Teleconnections on Hydrologic Regimes in Texas

NASA Astrophysics Data System (ADS)

Bhatia, N.; Singh, V. P.; Srivastav, R. K.

2016-12-01

Climate change is being alleged to have led to the increased frequency of extreme flooding events and the resulting damages are severe, especially where the flood-plain population densities are higher. Much research in the field of hydroclimatology is focusing on improving real-time flood forecasting models. Recent studies show that, in the state of Texas, extreme regional floods are actually triggered by abruptly higher precipitation intensities. Such intensities are further driven by sea-surface temperature and pressure anomalies, defined by certain patterns of teleconnections. In this study, climate variability is defined on the basis of five major Atlantic and Pacific Ocean related teleconnections: (i) Atlantic Multidecadal Oscillation (AMO), (ii) North Atlantic Oscillation (NAO), (iii) Pacific Decadal Oscillation (PDO), (iv) Pacific North American Pattern (PNA), and (v) Southern Oscillation Index (SOI). Hydrologic extremes will be modeled using probabilistic distributions. Leave-One-Out-Test (LOOT) will be employed to address the outliers in the extremes, and to eventually obtain the robust correlation coefficient. The variation in the effect of most correlated teleconnection with respect to hydrologic attributes will be investigated for the entire state. This study will attempt to identify potential teleconnection inputs for data-driven hydrologic models under varying climatic conditions.

Source-to-sink cycling of aeolian sediment in the north polar region of Mars

NASA Astrophysics Data System (ADS)

Ewing, R. C.; Kocurek, G.

2012-12-01

Aeolian sand dunes are prominent features on the landscapes of Earth, Mars, Venus and Titan and sedimentary deposits interpreted as aeolian in origin are found in the rock records of Earth and Mars. The widespread occurrence of aeolian dunes on the surface of these worlds and within their deep-time depositional records suggests that aeolian systems are and likely have been a default depositional environment for the Solar System. Within an aeolian source-to-sink context, we hypothesize that planet-specific boundary conditions strongly impact production, transport, accumulation and preservation of aeolian sediment, whereas dunes and dune-field patterns remain largely similar. This hypothesis is explored within the north polar region of Mars, which hosts the most extensive aeolian dune fields and aeolian sedimentary deposits yet recognized on Mars and appears to be a region of dynamic source-to-sink cycling of aeolian sediments. The Planum Boreum Cavi Unit rests beneath north polar ice cap of Mars and is composed of several hundred meters of niveo-aeolian dune cross-stratification. The overall architecture of the unit consists of sets of preserved dune topography with an upward increase in the abundance of ice. Dune sets are defined by stabilized, polygonally fractured bounding surfaces, erosional bounding surfaces and typical internal lee foresets made of sediment and ice. The accumulation of the Cavi Unit is interpreted as occurring through freezing and serves as an example of a cold temperature boundary condition on aeolian sediment accumulation. Preservation of the Cavi Unit arises because of deposition of the overlying ice cap and contrasts with preservation of aeolian sediment on Earth, which is largely driven by eustasy and tectonics. The Cavi Unit is thought to be one source of sediment for the north polar Olympia Undae Dune Field. The region of Olympia Undae near the Cavi Unit shows a reticulate dune field pattern composed of two sets of nearly orthogonal dune crestlines, with slipfaces on the primary crests, wind ripples, coarse-grained ripples and deflated interdune areas with exposed dune stratigraphy. Wind transport directions interpreted from wind ripple orientations show that the interaction between dune topography and wind flow on Mars are largely the same as on Earth giving rise to basic types of lee-slope processes - grain flow, grain fall and wind ripples. Using wind flow reconstruction and pattern analysis the pattern is interpreted as complex in which a younger pattern superposes a larger, older pattern. The younger pattern may have emerged with the development of the retreat of the Cavi reentrant into the Cavi Unit and ice cap, which acted to channel katabatic winds and inject a new sediment source into Olympia Undae. The similarity of the Olympia Undae dune-field pattern to dune-field patterns on other planets shows the robustness of pattern formation across different planetary boundary conditions and the applicability of pattern-analysis methods for paleoenvironmental reconstruction. The aeolian source-to-sink system of Mars' north polar region demonstrates how the stratigraphic and geomorphic principles of aeolian systems may differ because of different planetary boundary conditions and provides a framework for analysis of aeolian systems on other worlds.

Analysis of precipitation teleconnections in CMIP models as a measure of model fidelity in simulating precipitation

NASA Astrophysics Data System (ADS)

Langenbrunner, B.; Neelin, J.; Meyerson, J.

2011-12-01

The accurate representation of precipitation is a recurring issue in global climate models, especially in the tropics. Poor skill in modeling the variability and climate teleconnections associated with El Niño/Southern Oscillation (ENSO) also persisted in the latest Climate Model Intercomparison Project (CMIP) campaigns. Observed ENSO precipitation teleconnections provide a standard by which we can judge a given model's ability to reproduce precipitation and dynamic feedback processes originating in the tropical Pacific. Using CMIP3 Atmospheric Model Intercomparison Project (AMIP) runs as a baseline, we compare precipitation teleconnections between models and observations, and we evaluate these results against available CMIP5 historical and AMIP runs. Using AMIP simulations restricts evaluation to the atmospheric response, as sea surface temperatures (SSTs) in AMIP are prescribed by observations. We use a rank correlation between ENSO SST indices and precipitation to define teleconnections, since this method is robust to outliers and appropriate for non-Gaussian data. Spatial correlations of the modeled and observed teleconnections are then evaluated. We look at these correlations in regions of strong precipitation teleconnections, including equatorial S. America, the "horseshoe" region in the western tropical Pacific, and southern N. America. For each region and season, we create a "normalized projection" of a given model's teleconnection pattern onto that of the observations, a metric that assesses the quality of regional pattern simulations while rewarding signals of correct sign over the region. Comparing this to an area-averaged (i.e., more generous) metric suggests models do better when restrictions on exact spatial dependence are loosened and conservation constraints apply. Model fidelity in regional measures remains far from perfect, suggesting intrinsic issues with the models' regional sensitivities in moist processes.

Phase retrieval in digital speckle pattern interferometry by application of two-dimensional active contours called snakes.

PubMed

Federico, Alejandro; Kaufmann, Guillermo H

2006-03-20

We propose a novel approach to retrieving the phase map coded by a single closed-fringe pattern in digital speckle pattern interferometry, which is based on the estimation of the local sign of the quadrature component. We obtain the estimate by calculating the local orientation of the fringes that have previously been denoised by a weighted smoothing spline method. We carry out the procedure of sign estimation by determining the local abrupt jumps of size pi in the orientation field of the fringes and by segmenting the regions defined by these jumps. The segmentation method is based on the application of two-dimensional active contours (snakes), with which one can also estimate absent jumps, i.e., those that cannot be detected from the local orientation of the fringes. The performance of the proposed phase-retrieval technique is evaluated for synthetic and experimental fringes and compared with the results obtained with the spiral-phase- and Fourier-transform methods.

UPTAKE OF STRONTIUM-85 IN NON-MALIGNANT VERTEBRAL LESIONS IN MAN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bauer, G.C.H.; Scoccianti, P.

1961-01-01

By means of external scintillation counting, it was possible to demonstrate abnormally high spinal uptake of intravenously injected Sr/sup 85/ in various diseases of the vertebral column. A total dose of 50 mu c carrier-free Sr/sup 85/ was injected 7 to 14 days before recording spinal radioactivity with a collimated scintillation detector. An abnormal activity pattern was defined as a deviation from the normal pattern of twice the standard deviation of the normal mean value. Abnormal spinal patterns were detected in vertebral fractures, ankylosing spondylitis, tuberculous spondylitis, nonspecific discitis, and in a case with a lytic lesion of unknown origin.more » The value of 14 days was found more reliable than that at 7 days since by this time Sr/sup 85/ levels in soft tissues had fallen to low values. In 1 case, erroneous results were obtained from spinal counting due to a kidney stone which produced high activity in the spinal region. (H.H.D.)« less

Evolutionary history of Lissotriton helveticus: multilocus assessment of ancestral vs. recent colonization of the Iberian Peninsula.

PubMed

Recuero, Ernesto; García-París, Mario

2011-07-01

The Pleistocene was characterized by climatic changes that greatly altered the distribution of organisms. Population extinctions, bottlenecks, isolation, range expansions and contractions were often associated with glaciations, leaving signatures in the spatial patterns of genetic diversity across species. Lissotriton helveticus belongs to a Pan-European lineage of newts that were strongly affected by glaciations and represent an excellent model to analyse the effect of generalized climatic changes in phylogeographic patterns. We studied the genetic diversity of the species using data from two mitochondrial and three nuclear genes analyzed in a Bayesian phylogenetic framework to investigate the historical processes shaping spatial patterns of genetic diversity. Mitochondrial haplotypes cluster in four different groups present in the Iberian Peninsula and of Pleistocene origin, probably by allopatric fragmentation. Nuclear genes present no obvious geographic structure patterns, suggesting gene flow and generalized incomplete lineage sorting. Populations north of the Pyrenees are closely related to those from northeastern Iberia, suggesting recent range expansion from this region. Historical demographic analyses indicate a demographic expansion starting about 100,000years ago and more recent population declines. Compared to other Lissotriton species, L. helveticus includes only relatively young genetic lineages, suggesting a Central European pre-Pleistocene distribution followed by complete extirpation of the species during glaciations in that area. Historical demographic trends in the Iberian Peninsula are reversed with respect to the more Mediterranean species Lissotriton boscai, indicating different responses of both species to climate changes. Diversity patterns among Lissotriton species seem to be defined by four main factors: ancestral distributions, colonization capabilities, interactions with other species and effective population sizes. Differences in these factors define two types of species, referred to as "R" (refugia) and "S" (sanctuaries) that explain part of the diversity in patterns of genetic diversity created by glaciations in Western Europe. Copyright © 2011 Elsevier Inc. All rights reserved.

Local-scale analysis of temperature patterns over Poland during heatwave events

NASA Astrophysics Data System (ADS)

Krzyżewska, Agnieszka; Dyer, Jamie

2018-01-01

Heatwaves are predicted to increase in frequency, duration, and severity in the future, including over Central Europe where populations are sensitive to extreme temperature. This paper studies six recent major heatwave events over Poland from 2006 through 2015 using regional-scale simulations (10-km grid spacing, hourly frequency) from the Weather Research and Forecast (WRF) model to define local-scale 2-m temperature patterns. For this purpose, a heatwave is defined as at least three consecutive days with maximum 2-m air temperature exceeding 30 °C. The WRF simulations were validated using maximum daily 2-m temperature observations from 12 meteorological stations in select Polish cities, which were selected to have even spatial coverage across the study area. Synoptic analysis of the six study events shows that the inflow of tropical air masses from the south is the primary driver of heatwave onset and maintenance, the highest temperatures (and most vulnerable areas) occur over arable land and artificial surfaces in central and western Poland, while coastal areas in the north, mountain areas in the south, and forested and mosaic areas of smaller fields and pastures of the northwest, northeast, and southeast are less affected by prolonged periods of elevated temperatures. In general, regional differences in 2-m temperature between the hottest and coolest areas is about 2-4 °C. Large urban areas like Warsaw, or the large complex of artificial areas in the conurbation of Silesian cities, are also generally warmer than surrounding areas by roughly 2-4 °C, and even up to 6 °C, especially during the night. Additionally, hot air from the south of Poland flows through a low-lying area between two mountain ranges (Sudetes and Carpathian Mountains)—the so-called Moravian Gate—hitting densely populated urban areas (Silesian cities) and Cracow. These patterns occur only during high-pressure synoptic conditions with low cloudiness and wind and without any active fronts or mesoscale convective disturbances.

Deterministic seismogenic scenarios based on asperities spatial distribution to assess tsunami hazard on northern Chile (18°S to 24°S)

NASA Astrophysics Data System (ADS)

González-Carrasco, J. F.

2016-12-01

Southern Peru and northern Chile coastal areas, extended between 12º to 24ºS, have been recognized as a mature seismic gap with a high seismogenic potential associated to seismic moment deficit accumulated since 1877. An important scientific question is which will be the breaking pattern of a future megathrust earthquake, being relevant from hazard assessment perspective. During the last decade, the occurrence of three major subduction earthquakes has given the possibility to acquire outstanding geophysical and geological information to know the behavior of phenomena. An interesting result is the relationship between the maximum slip areas and the spatial distribution of asperities in subduction zones. In this contribution, we propose a methodology to identify a regional pattern of main asperities to construct reliable seismogenic scenarios in a seismic gap. We follow a deterministic approach to explore the distribution of asperities segmentation using geophysical and geodetic data as trench-parallel gravity anomaly (TPGA), interseismic coupling (ISC), b-value, historical moment release, residual bathymetric and gravity anomalies. The combined information represents physical constraints for short and long term suitable regions for future mega earthquakes. To illuminate the asperities distribution, we construct profiles using fault coordinates, along-strike and down-dip direction, of all proxies to define the boundaries of a major asperities (> 100 km). The geometry of a major asperity is useful to define a finite set of future deterministic seismogenic scenarios to evaluate tsunamigenic hazard in main cities of northern zone of Chile (18°S to 24°S).

Helmet-induced headache among Danish military personnel.

PubMed

Rahmani, Zakia; Kochanek, Aneta; Astrup, Jesper Johnsen; Poulsen, Jeppe Nørgaard; Gazerani, Parisa

2017-12-01

External compression headache is defined as a headache caused by an external physical compression applied on the head. It affects about 4% of the general population; however, certain populations (e.g. construction workers and military personnel) with particular needs of headwear or helmet are at higher risk of developing this type of headache. External compression headache is poorly studied in relation to specific populations. This study aimed to investigate the prevalence and pattern of helmet-induced external compression headache among Danish military personnel of the Northern Jutland region in Denmark. Data acquisition was based on a custom-made questionnaire delivered to volunteers who used helmets in the Danish military service and who agreed to participate in this study. The military of the Northern Jutland region of Denmark facilitated recruitment of the participants. The questionnaires were delivered on paper and the collected (anonymous) answers (total 279) were used for further analysis. About 30% of the study participants reported headache in relation to wearing a military helmet. Headache was defined as a pressing pain predominantly in the front of the head with an average intensity of 4 on a visual analogue scale of 0 (no pain) to 10 (worst pain imaginable). It was also found that helmets with different designs influenced both the occurrence of headache and its characteristics. This study is the first to demonstrate the prevalence and pattern of compression headache among military personnel in North Jutland, Denmark. The findings of this study call for further attention to helmet-induced external compression headache and strategies to minimize the burden.

Anisotropies in the perceived spatial displacement of motion-defined contours: opposite biases in the upper-left and lower-right visual quadrants.

PubMed

Fan, Zhao; Harris, John

2010-10-12

In a recent study (Fan, Z., & Harris, J. (2008). Perceived spatial displacement of motion-defined contours in peripheral vision. Vision Research, 48(28), 2793-2804), we demonstrated that virtual contours defined by two regions of dots moving in opposite directions were displaced perceptually in the direction of motion of the dots in the more eccentric region when the contours were viewed in the right visual field. Here, we show that the magnitude and/or direction of these displacements varies in different quadrants of the visual field. When contours were presented in the lower visual field, the direction of perceived contour displacement was consistent with that when both contours were presented in the right visual field. However, this illusory motion-induced spatial displacement disappeared when both contours were presented in the upper visual field. Also, perceived contour displacement in the direction of the more eccentric dots was larger in the right than in the left visual field, perhaps because of a hemispheric asymmetry in attentional allocation. Quadrant-based analyses suggest that the pattern of results arises from opposite directions of perceived contour displacement in the upper-left and lower-right visual quadrants, which depend on the relative strengths of two effects: a greater sensitivity to centripetal motion, and an asymmetry in the allocation of spatial attention. Copyright © 2010 Elsevier Ltd. All rights reserved.

Regulatory analysis of the mouse Hoxb3 gene: multiple elements work in concert to direct temporal and spatial patterns of expression.

PubMed

Kwan, C T; Tsang, S L; Krumlauf, R; Sham, M H

2001-04-01

The expression pattern of the mouse Hoxb3 gene is exceptionally complex and dynamic compared with that of other members of the Hoxb cluster. There are multiple types of transcripts for Hoxb3 gene, and the anterior boundaries of its expression vary at different stages of development. Two enhancers flanking Hoxb3 on the 3' and 5' sides regulate Hoxb2 and Hoxb4, respectively, and these control regions define the two ends of a 28-kb interval in and around the Hoxb3 locus. To assay the regulatory potential of DNA fragments in this interval we have used transgenic analysis with a lacZ reporter gene to locate cis-elements for directing the dynamic patterns of Hoxb3 expression. Our detailed analysis has identified four new and widely spaced cis-acting regulatory regions that can together account for major aspects of the Hoxb3 expression pattern. Elements Ib, IIIa, and IVb control gene expression in neural and mesodermal tissues; element Va controls mesoderm-specific gene expression. The most anterior neural expression domain of Hoxb3 is controlled by an r5 enhancer (element IVa); element IIIa directs reporter expression in the anterior spinal cord and hindbrain up to r6, and the region A enhancer (in element I) mediates posterior neural expression. Hence, the regulation of segmental expression of Hoxb3 in the hindbrain is different from that of Hoxa3, as two separate enhancer elements contribute to expression in r5 and r6. The mesoderm-specific element (Va) directs reporter expression to prevertebra C1 at 12.5 dpc, which is the anterior limit of paraxial mesoderm expression for Hoxb3. When tested in combinations, these cis-elements appear to work as modules in an additive manner to recapitulate the major endogenous expression patterns of Hoxb3 during embryogenesis. Together our study shows that multiple control elements direct reporter gene expression in diverse tissue-, temporal-, and spatially restricted subset of the endogenous Hoxb3 expression domains and work in concert to control the neural and mesodermal patterns of expression. Copyright 2001 Academic Press.

Role of moisture transport for Central American precipitation

NASA Astrophysics Data System (ADS)

María Durán-Quesada, Ana; Gimeno, Luis; Amador, Jorge

2017-02-01

A climatology of moisture sources linked with Central American precipitation was computed based upon Lagrangian trajectories for the analysis period 1980-2013. The response of the annual cycle of precipitation in terms of moisture supply from the sources was analysed. Regional precipitation patterns are mostly driven by moisture transport from the Caribbean Sea (CS). Moisture supply from the eastern tropical Pacific (ETPac) and northern South America (NSA) exhibits a strong seasonal pattern but weaker compared to CS. The regional distribution of rainfall is largely influenced by a local signal associated with surface fluxes during the first part of the rainy season, whereas large-scale dynamics forces rainfall during the second part of the rainy season. The Caribbean Low Level Jet (CLLJ) and the Chocó Jet (CJ) are the main conveyors of regional moisture, being key to define the seasonality of large-scale forced rainfall. Therefore, interannual variability of rainfall is highly dependent of the regional LLJs to the atmospheric variability modes. The El Niño-Southern Oscillation (ENSO) was found to be the dominant mode affecting moisture supply for Central American precipitation via the modulation of regional phenomena. Evaporative sources show opposite anomaly patterns during warm and cold ENSO phases, as a result of the strengthening and weakening, respectively, of the CLLJ during the summer months. Trends in both moisture supply and precipitation over the last three decades were computed, results suggest that precipitation trends are not homogeneous for Central America. Trends in moisture supply from the sources identified show a marked north-south seesaw, with an increasing supply from the CS Sea to northern Central America. Long-term trends in moisture supply are larger for the transition months (March and October). This might have important implications given that any changes in the conditions seen during the transition to the rainy season may induce stronger precipitation trends.

Large-scale spatio-temporal monitoring highlights hotspots of demersal fish diversity in the Mediterranean Sea

NASA Astrophysics Data System (ADS)

Granger, Victoria; Fromentin, Jean-Marc; Bez, Nicolas; Relini, Giulio; Meynard, Christine N.; Gaertner, Jean-Claude; Maiorano, Porzia; Garcia Ruiz, Cristina; Follesa, Cristina; Gristina, Michele; Peristeraki, Panagiota; Brind'Amour, Anik; Carbonara, Pierluigi; Charilaou, Charis; Esteban, Antonio; Jadaud, Angélique; Joksimovic, Aleksandar; Kallianiotis, Argyris; Kolitari, Jerina; Manfredi, Chiara; Massuti, Enric; Mifsud, Roberta; Quetglas, Antoni; Refes, Wahid; Sbrana, Mario; Vrgoc, Nedo; Spedicato, Maria Teresa; Mérigot, Bastien

2015-01-01

Increasing human pressures and global environmental change may severely affect the diversity of species assemblages and associated ecosystem services. Despite the recent interest in phylogenetic and functional diversity, our knowledge on large spatio-temporal patterns of demersal fish diversity sampled by trawling remains still incomplete, notably in the Mediterranean Sea, one of the most threatened marine regions of the world. We investigated large spatio-temporal diversity patterns by analysing a dataset of 19,886 hauls from 10 to 800 m depth performed annually during the last two decades by standardised scientific bottom trawl field surveys across the Mediterranean Sea, within the MEDITS program. A multi-component (eight diversity indices) and multi-scale (local assemblages, biogeographic regions to basins) approach indicates that only the two most traditional components (species richness and evenness) were sufficient to reflect patterns in taxonomic, phylogenetic or functional richness and divergence. We also put into question the use of widely computed indices that allow comparing directly taxonomic, phylogenetic and functional diversity within a unique mathematical framework. In addition, demersal fish assemblages sampled by trawl do not follow a continuous decreasing longitudinal/latitudinal diversity gradients (spatial effects explained up to 70.6% of deviance in regression tree and generalised linear models), for any of the indices and spatial scales analysed. Indeed, at both local and regional scales species richness was relatively high in the Iberian region, Malta, the Eastern Ionian and Aegean seas, meanwhile the Adriatic Sea and Cyprus showed a relatively low level. In contrast, evenness as well as taxonomic, phylogenetic and functional divergences did not show regional hotspots. All studied diversity components remained stable over the last two decades. Overall, our results highlight the need to use complementary diversity indices through different spatial scales when developing conservation strategies and defining delimitations for protected areas.

Projections of Flood Risk using Credible Climate Signals in the Ohio River Basin

NASA Astrophysics Data System (ADS)

Schlef, K.; Robertson, A. W.; Brown, C.

2017-12-01

Estimating future hydrologic flood risk under non-stationary climate is a key challenge to the design of long-term water resources infrastructure and flood management strategies. In this work, we demonstrate how projections of large-scale climate patterns can be credibly used to create projections of long-term flood risk. Our study area is the northwest region of the Ohio River Basin in the United States Midwest. In the region, three major teleconnections have been previously demonstrated to affect synoptic patterns that influence extreme precipitation and streamflow: the El Nino Southern Oscillation, the Pacific North American pattern, and the Pacific Decadal Oscillation. These teleconnections are strongest during the winter season (January-March), which also experiences the greatest number of peak flow events. For this reason, flood events are defined as the maximum daily streamflow to occur in the winter season. For each gage in the region, the location parameter of a log Pearson type 3 distribution is conditioned on the first principal component of the three teleconnections to create a statistical model of flood events. Future projections of flood risk are created by forcing the statistical model with projections of the teleconnections from general circulation models selected for skill. We compare the results of our method to the results of two other methods: the traditional model chain (i.e., general circulation model projections to downscaling method to hydrologic model to flood frequency analysis) and that of using the historic trend. We also discuss the potential for developing credible projections of flood events for the continental United States.

Time trends of chronic HBV infection over prior decades - A global analysis.

PubMed

Ott, Jördis J; Horn, Johannes; Krause, Gérard; Mikolajczyk, Rafael T

2017-01-01

Information on trends in chronic hepatitis B virus (HBV) prevalence across countries is lacking. We studied changes in chronic HBV infection over previous decades by country, and assessed patterns of change between and within WHO-defined regions. Based on data from a published systematic review on chronic HBV, we applied a linear model on the logit scale to assess time trends in country-specific prevalence. Estimated HBsAg prevalence in 2000 and relative changes in prevalence over time were evaluated by country and region. Sufficient data were available for 50 countries, mostly showing reductions in prevalence over time. Various degrees of heterogeneity were observed within regions, with a relatively homogenous pattern in the Eastern Mediterranean region with strong decreases in HBsAg prevalence. Europe showed a mixed pattern: higher and stable chronic HBsAg prevalence in Eastern, and constantly low prevalence in Western Europe. In Africa, some countries demonstrated no change in prevalence; increases were seen in Uganda (odds ratio 1.05 per year; 95% confidence interval 1.04-1.06), Nigeria (1.02; 1.02-1.02), Senegal (1.01; 1.01-1.02), and South Africa (1.02; 1.01-1.02). With some exceptions, country-patterns overlapped among countries of South East Asian and Western Pacific regions, characterized by low-medium HBsAg decreases, most prominent in China and Malaysia. Most countries experienced decreases in HBsAg prevalence. Dynamics varied, even within regions; decreases occurred mostly before the direct effects of childhood vaccination may have manifested. These findings together with stable and increasing HBsAg prevalence in some countries of Africa and Eastern Europe indicate the need for further tailored country-specific prevention. This study investigated time trends in prevalence of chronic HBV infection in 50 countries worldwide over the last decade, by estimating relative changes in prevalence. Results show decreases in chronic HBV infection in most countries; no changes or increases in prevalence are noted in some African countries. Reasons for time changes need to be investigated further; based on the results, various prevention measures have contributed to reductions, and further tailored HBV prevention is required to combat the disease on a global level. Copyright © 2016 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Global hotspots of river erosion under global warming

NASA Astrophysics Data System (ADS)

Plink-Bjorklund, P.; Reichler, T.

2017-12-01

Extreme precipitation plays a significant role for river hydrology, flood hazards and landscape response. For example, the September 2013 rainstorm in the Colorado Front Range evacuated the equivalent of hundreds to thousands of years of hillslope weathering products. Although promoted by steep topography, the Colorado event is clearly linked to rainfall intensity, since most of the 1100 debris flows occurred within the highest rainfall contour. Additional evidence for a strong link between extreme precipitation and river erosion comes from the sedimentary record, and especially from that of past greenhouse climates. The existence of such a link suggests that information about global rainfall patterns can be used to define regions of increased erosion potential. However, the question arises what rainfall criteria to use and how well the method works. A related question is how ongoing climate change and the corresponding shifts in rainfall might impact the results. Here, we use atmospheric reanalysis and output from a climate model to identify regions that are particularly susceptible to landscape change in response to extreme precipitation. In order to define the regions, we combine several hydroclimatological and geomorphological criteria into a single index of erosion potential. We show that for current climate, our criteria applied to atmospheric reanalysis or to climate model data successfully localize known areas of increased erosion potential, such as the Colorado region. We then apply our criteria to climate model data for future climate to document how the location, extent, and intensity of erosion hotspots are likely to change under global warming.

Spatial data analysis for exploration of regional scale geothermal resources

NASA Astrophysics Data System (ADS)

Moghaddam, Majid Kiavarz; Noorollahi, Younes; Samadzadegan, Farhad; Sharifi, Mohammad Ali; Itoi, Ryuichi

2013-10-01

Defining a comprehensive conceptual model of the resources sought is one of the most important steps in geothermal potential mapping. In this study, Fry analysis as a spatial distribution method and 5% well existence, distance distribution, weights of evidence (WofE), and evidential belief function (EBFs) methods as spatial association methods were applied comparatively to known geothermal occurrences, and to publicly-available regional-scale geoscience data in Akita and Iwate provinces within the Tohoku volcanic arc, in northern Japan. Fry analysis and rose diagrams revealed similar directional patterns of geothermal wells and volcanoes, NNW-, NNE-, NE-trending faults, hotsprings and fumaroles. Among the spatial association methods, WofE defined a conceptual model correspondent with the real world situations, approved with the aid of expert opinion. The results of the spatial association analyses quantitatively indicated that the known geothermal occurrences are strongly spatially-associated with geological features such as volcanoes, craters, NNW-, NNE-, NE-direction faults and geochemical features such as hotsprings, hydrothermal alteration zones and fumaroles. Geophysical data contains temperature gradients over 100 °C/km and heat flow over 100 mW/m2. In general, geochemical and geophysical data were better evidence layers than geological data for exploring geothermal resources. The spatial analyses of the case study area suggested that quantitative knowledge from hydrothermal geothermal resources was significantly useful for further exploration and for geothermal potential mapping in the case study region. The results can also be extended to the regions with nearly similar characteristics.

Climatology and trends of summer high temperature days in India during 1969-2013

NASA Astrophysics Data System (ADS)

Jaswal, A. K.; Rao, P. C. S.; Singh, Virendra

2015-02-01

Based on the daily maximum air temperature data from 176 stations in India from 1969 to 2013, the climatological distribution of the number of days with high temperature (HT) defined as days with maximum temperature higher than 37°C during summer season (March-June) are studied. With a focus on the regional variability and long-term trends, the impacts of HT days are examined by dividing the country into six geographical regions (North, West, North-central, East, South-central and South). Although the long-term (1969-2013) climatological numbers of HT days display well-defined spatial patterns, there is clear change in climatological mean and coefficient of variation of HT days in a recent period (1991-2013). The long period trends indicate increase in summer HT days by 3%, 5%, and 18% in north, west, and south regions, respectively and decrease by 4% and 9% in north-central and east regions respectively. However, spatial variations in HT days exist across different regions in the country. The data analysis shows that 2010 was the warmest summer year and 2013 was the coolest summer year in India. Comparison of spatial distributions of trends in HT days for 1969-1990 and 1991-2013 periods reveal that there is an abrupt increase in the number of HT days over north, west and north-central regions of India probably from mid 1990s. A steep increase in summer HT days in highly populated cities of Mumbai, New Delhi, Chennai, Jaipur, and Visakhapatnam is noticed during the recent period of 1991-2013. The summer HT days over southern India indicate significant positive correlation with Nino 3.4 index for three months' running mean (December-January-February, January-March, February-April, March-May and April-June).

Muscle MRI in patients with dysferlinopathy: pattern recognition and implications for clinical trials.

PubMed

Diaz-Manera, Jordi; Fernandez-Torron, Roberto; LLauger, Jaume; James, Meredith K; Mayhew, Anna; Smith, Fiona E; Moore, Ursula R; Blamire, Andrew M; Carlier, Pierre G; Rufibach, Laura; Mittal, Plavi; Eagle, Michelle; Jacobs, Marni; Hodgson, Tim; Wallace, Dorothy; Ward, Louise; Smith, Mark; Stramare, Roberto; Rampado, Alessandro; Sato, Noriko; Tamaru, Takeshi; Harwick, Bruce; Rico Gala, Susana; Turk, Suna; Coppenrath, Eva M; Foster, Glenn; Bendahan, David; Le Fur, Yann; Fricke, Stanley T; Otero, Hansel; Foster, Sheryl L; Peduto, Anthony; Sawyer, Anne Marie; Hilsden, Heather; Lochmuller, Hanns; Grieben, Ulrike; Spuler, Simone; Tesi Rocha, Carolina; Day, John W; Jones, Kristi J; Bharucha-Goebel, Diana X; Salort-Campana, Emmanuelle; Harms, Matthew; Pestronk, Alan; Krause, Sabine; Schreiber-Katz, Olivia; Walter, Maggie C; Paradas, Carmen; Hogrel, Jean-Yves; Stojkovic, Tanya; Takeda, Shin'ichi; Mori-Yoshimura, Madoka; Bravver, Elena; Sparks, Susan; Bello, Luca; Semplicini, Claudio; Pegoraro, Elena; Mendell, Jerry R; Bushby, Kate; Straub, Volker

2018-05-07

Dysferlinopathies are a group of muscle disorders caused by mutations in the DYSF gene. Previous muscle imaging studies describe a selective pattern of muscle involvement in smaller patient cohorts, but a large imaging study across the entire spectrum of the dysferlinopathies had not been performed and previous imaging findings were not correlated with functional tests. We present cross-sectional T1-weighted muscle MRI data from 182 patients with genetically confirmed dysferlinopathies. We have analysed the pattern of muscles involved in the disease using hierarchical analysis and presented it as heatmaps. Results of the MRI scans have been correlated with relevant functional tests for each region of the body analysed. In 181 of the 182 patients scanned, we observed muscle pathology on T1-weighted images, with the gastrocnemius medialis and the soleus being the most commonly affected muscles. A similar pattern of involvement was identified in most patients regardless of their clinical presentation. Increased muscle pathology on MRI correlated positively with disease duration and functional impairment. The information generated by this study is of high diagnostic value and important for clinical trial development. We have been able to describe a pattern that can be considered as characteristic of dysferlinopathy. We have defined the natural history of the disease from a radiological point of view. These results enabled the identification of the most relevant regions of interest for quantitative MRI in longitudinal studies, such as clinical trials. NCT01676077. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Soaring Migratory Birds Avoid Wind Farm in the Isthmus of Tehuantepec, Southern Mexico

PubMed Central

Villegas-Patraca, Rafael; Cabrera-Cruz, Sergio A.; Herrera-Alsina, Leonel

2014-01-01

The number of wind farms operating in the Isthmus of Tehuantepec, southern Mexico, has rapidly increased in recent years; yet, this region serves as a major migration route for various soaring birds, including Turkey Vultures (Cathartes aura) and Swainson's Hawks (Buteo swainsoni). We analyzed the flight trajectories of soaring migrant birds passing the La Venta II wind farm during the two migratory seasons of 2011, to determine whether an avoidance pattern existed or not. We recorded three polar coordinates for the flight path of migrating soaring birds that were detected using marine radar, plotted the flight trajectories and estimated the number of trajectories that intersected the polygon defined by the wind turbines of La Venta II. Finally, we estimated the actual number of intersections per kilometer and compared this value with the null distributions obtained by running 10,000 simulations of our datasets. The observed number of intersections per kilometer fell within or beyond the lower end of the null distributions in the five models proposed for the fall season and in three of the four models proposed for the spring season. Flight trajectories had a non-random distribution around La Venta II, suggesting a strong avoidance pattern during fall and a possible avoidance pattern during spring. We suggest that a nearby ridgeline plays an important role in this pattern, an issue that may be incorporated into strategies to minimize the potential negative impacts of future wind farms on soaring birds. Studies evaluating these issues in the Isthmus of Tehuantepec have not been previously published; hence this work contributes important baseline information about the movement patterns of soaring birds and its relationship to wind farms in the region. PMID:24647442

Soaring migratory birds avoid wind farm in the Isthmus of Tehuantepec, southern Mexico.

PubMed

Villegas-Patraca, Rafael; Cabrera-Cruz, Sergio A; Herrera-Alsina, Leonel

2014-01-01

The number of wind farms operating in the Isthmus of Tehuantepec, southern Mexico, has rapidly increased in recent years; yet, this region serves as a major migration route for various soaring birds, including Turkey Vultures (Cathartes aura) and Swainson's Hawks (Buteo swainsoni). We analyzed the flight trajectories of soaring migrant birds passing the La Venta II wind farm during the two migratory seasons of 2011, to determine whether an avoidance pattern existed or not. We recorded three polar coordinates for the flight path of migrating soaring birds that were detected using marine radar, plotted the flight trajectories and estimated the number of trajectories that intersected the polygon defined by the wind turbines of La Venta II. Finally, we estimated the actual number of intersections per kilometer and compared this value with the null distributions obtained by running 10,000 simulations of our datasets. The observed number of intersections per kilometer fell within or beyond the lower end of the null distributions in the five models proposed for the fall season and in three of the four models proposed for the spring season. Flight trajectories had a non-random distribution around La Venta II, suggesting a strong avoidance pattern during fall and a possible avoidance pattern during spring. We suggest that a nearby ridgeline plays an important role in this pattern, an issue that may be incorporated into strategies to minimize the potential negative impacts of future wind farms on soaring birds. Studies evaluating these issues in the Isthmus of Tehuantepec have not been previously published; hence this work contributes important baseline information about the movement patterns of soaring birds and its relationship to wind farms in the region.

Micro-seismicity and seismotectonic study in Western Himalaya-Ladakh-Karakoram using local broadband seismic data

NASA Astrophysics Data System (ADS)

Kanna, Nagaraju; Gupta, Sandeep; Prakasam, K. S.

2018-02-01

We document the seismic activity and fault plane solutions (FPSs) in the Western Himalaya, Ladakh and Karakoram using data from 16 broadband seismographs operated during June 2002 to December 2003. We locate 206 earthquakes with a local magnitude in the range of 1.5 to 4.9 and calculate FPSs of 19 selected earthquakes based on moment tensor solutions. The earthquakes are distributed throughout the study region and indicate active tectonics in this region. The observed seismicity pattern is quite different than a well-defined pattern of seismicity, along the Main Central Thrust zone, in the eastern side of the study region (i.e., Kumaon-Garhwal Himalaya). In the Himalaya region, the earthquakes are distributed in the crust and upper mantle, whereas in the Ladakh-Karakoram area the earthquakes are mostly confined up to crustal depths. The fault plane solutions show a mixture of thrust, normal and strike-slip type mechanisms, which are well corroborated with the known faults/tectonics of the region. The normal fault earthquakes are observed along the Southern Tibet Detachment, Zanskar Shear Zone, Tso-Morari dome, and Kaurik-Chango fault; and suggest E-W extension tectonics in the Higher and Tethys Himalaya. The earthquakes of thrust mechanism with the left-lateral strike-slip component are seen along the Kistwar fault. The right-lateral strike-slip faulting with thrust component along the bending of the Main Boundary Thrust and Main Central Thrust shows the transpressional tectonics in this part of the Himalaya. The observed earthquakes with right-lateral strike-slip faulting indicate seismically active nature of the Karakoram fault.

Changing patterns in the association between regional socio-economic context and dental caries experience according to gender and age: a multilevel study in Korean adults.

PubMed

Lee, Hoo-Yeon; Choi, Youn-Hee; Park, Hyoung Wook; Lee, Sang Gyu

2012-07-28

Little is known about the effects of socio-environmental factors on dental caries in different demographic situations in Asian populations. We investigated whether the nature of the association between regional socio-economic context and dental caries experience differed according to gender and age groups in Korean adults. We obtained a linked data set containing individual information from the 2000 Korean National Oral Health Survey and regional information from the "Major statistical indices of Si-Gun-Gu" (city-county-ward), published by the Korean Statistical Office. We stratified participants into women and men and into four 10-year-interval age groups (19-34, 35-44, 45-54, and 55-64 years) and analysed the linked data using a multilevel analysis. In total, 5,259 individuals were included in the final study population. Regional socio-economic context was significantly associated with dental caries experience in men, but not in women. The patterns of the association between regional contextual variables and dental caries experience differed among age groups. People 35-44 years of age living in areas less dependent on the manufacturing industry and those 45-54 years of age living in areas where local government was relatively poor were more prone to have caries experience. The results of this study indicated that socio-economic factors affecting residents' dental health status may operate through different mechanisms or degrees according to geographic location, suggesting that some gender- and age-defined subgroups may be likely to benefit from different types of intervention, including the development of specific health policies.

Addressing the mischaracterization of extreme rainfall in regional climate model simulations - A synoptic pattern based bias correction approach

NASA Astrophysics Data System (ADS)

Li, Jingwan; Sharma, Ashish; Evans, Jason; Johnson, Fiona

2018-01-01

Addressing systematic biases in regional climate model simulations of extreme rainfall is a necessary first step before assessing changes in future rainfall extremes. Commonly used bias correction methods are designed to match statistics of the overall simulated rainfall with observations. This assumes that change in the mix of different types of extreme rainfall events (i.e. convective and non-convective) in a warmer climate is of little relevance in the estimation of overall change, an assumption that is not supported by empirical or physical evidence. This study proposes an alternative approach to account for the potential change of alternate rainfall types, characterized here by synoptic weather patterns (SPs) using self-organizing maps classification. The objective of this study is to evaluate the added influence of SPs on the bias correction, which is achieved by comparing the corrected distribution of future extreme rainfall with that using conventional quantile mapping. A comprehensive synthetic experiment is first defined to investigate the conditions under which the additional information of SPs makes a significant difference to the bias correction. Using over 600,000 synthetic cases, statistically significant differences are found to be present in 46% cases. This is followed by a case study over the Sydney region using a high-resolution run of the Weather Research and Forecasting (WRF) regional climate model, which indicates a small change in the proportions of the SPs and a statistically significant change in the extreme rainfall over the region, although the differences between the changes obtained from the two bias correction methods are not statistically significant.

Quantifying relief on alluvial fans using airborne lidar to reveal patterns of sediment accumulation

NASA Astrophysics Data System (ADS)

Morelan, A. E., III; Oskin, M. E.

2017-12-01

We present a method of quantifying detailed surface relief on alluvial fans from high-resolution topography. Average slope and curvature of the fan are used together to empirically derive an idealized, radially symmetric fan surface, from which we compute residual topography. Maps produced using this technique highlight spatial patterns of fan deposition and avulsion. Regions of high residual topography reveal active and abandoned sediment lobes accumulated from recent depositional events, often with well-defined channels at their apex. Preliminary observations suggest that surface relief is uniform across a collection of fans in a given region and source lithology. Alluvial fans with granitic catchment lithologies in eastern California (n=12), each with varying source catchment size and mean fan slope, all show relief of around 4 meters. A collection of fans from the Carrizo Plain in central California (n=12), with source catchments set within Miocene marine and nonmarine sedimentary rocks, show significantly lower relief values around 2 meters. We hypothesize that particle grain size determines this contrasting relief through its control on the thickness of fan-building debris flows. In both settings we find that sediment lobes tend to extend toward the fan toe. This pattern supports a process, observed in analog experiments, of fan deposition dominated by back-filling and overtopping of distributary channels by debris-flows.

Analysing human mobility patterns of hiking activities through complex network theory.

PubMed

Lera, Isaac; Pérez, Toni; Guerrero, Carlos; Eguíluz, Víctor M; Juiz, Carlos

2017-01-01

The exploitation of high volume of geolocalized data from social sport tracking applications of outdoor activities can be useful for natural resource planning and to understand the human mobility patterns during leisure activities. This geolocalized data represents the selection of hike activities according to subjective and objective factors such as personal goals, personal abilities, trail conditions or weather conditions. In our approach, human mobility patterns are analysed from trajectories which are generated by hikers. We propose the generation of the trail network identifying special points in the overlap of trajectories. Trail crossings and trailheads define our network and shape topological features. We analyse the trail network of Balearic Islands, as a case of study, using complex weighted network theory. The analysis is divided into the four seasons of the year to observe the impact of weather conditions on the network topology. The number of visited places does not decrease despite the large difference in the number of samples of the two seasons with larger and lower activity. It is in summer season where it is produced the most significant variation in the frequency and localization of activities from inland regions to coastal areas. Finally, we compare our model with other related studies where the network possesses a different purpose. One finding of our approach is the detection of regions with relevant importance where landscape interventions can be applied in function of the communities.

Effects of seasonality on drosophilids (Insecta, Diptera) in the northern part of the Atlantic Forest, Brazil.

PubMed

Coutinho-Silva, R D; Montes, M A; Oliveira, G F; de Carvalho-Neto, F G; Rohde, C; Garcia, A C L

2017-10-01

Seasonality is an important aspect associated with population dynamic and structure of tropical insect assemblages. This study evaluated the effects of seasonality on abundance, richness, diversity and composition of an insect group, drosophilids, including species native to the Neotropical region and exotic ones. Three preserved fragments of the northern Atlantic Forest were surveyed, where temperatures are above 20 °C throughout the year and rainfall regimes define two seasons (dry and rainy). As opposed to other studies about arthropods in tropical regions, we observed that abundance of drosophilids was significantly higher in the dry season, possibly due to biological aspects and the colonization strategy adopted by the exotic species in these environments. Contrarily to abundance, we did not observe a seasonal pattern for richness. As for other parts of the Atlantic Forest, the most representative Neotropical species (Drosophila willistoni, D. sturtevanti, D. paulistorum and D. prosaltans) were significantly more abundant in the rainy season. Among the most abundant exotic species, D. malerkotliana, Zaprionus indianus and Scaptodrosophila latifasciaeformis were more importantly represented the dry season, while D. simulans was more abundant in the rainy period. The seasonality patterns exhibited by the most abundant species were compared to findings published in other studies. Our results indicate that exotic species were significantly more abundant in the dry season, while native ones exhibited an opposite pattern.

Analysing human mobility patterns of hiking activities through complex network theory

PubMed Central

Pérez, Toni; Guerrero, Carlos; Eguíluz, Víctor M.; Juiz, Carlos

2017-01-01

The exploitation of high volume of geolocalized data from social sport tracking applications of outdoor activities can be useful for natural resource planning and to understand the human mobility patterns during leisure activities. This geolocalized data represents the selection of hike activities according to subjective and objective factors such as personal goals, personal abilities, trail conditions or weather conditions. In our approach, human mobility patterns are analysed from trajectories which are generated by hikers. We propose the generation of the trail network identifying special points in the overlap of trajectories. Trail crossings and trailheads define our network and shape topological features. We analyse the trail network of Balearic Islands, as a case of study, using complex weighted network theory. The analysis is divided into the four seasons of the year to observe the impact of weather conditions on the network topology. The number of visited places does not decrease despite the large difference in the number of samples of the two seasons with larger and lower activity. It is in summer season where it is produced the most significant variation in the frequency and localization of activities from inland regions to coastal areas. Finally, we compare our model with other related studies where the network possesses a different purpose. One finding of our approach is the detection of regions with relevant importance where landscape interventions can be applied in function of the communities. PMID:28542280

Regional-scale drivers of forest structure and function in northwestern Amazonia.

PubMed

Higgins, Mark A; Asner, Gregory P; Anderson, Christopher B; Martin, Roberta E; Knapp, David E; Tupayachi, Raul; Perez, Eneas; Elespuru, Nydia; Alonso, Alfonso

2015-01-01

Field studies in Amazonia have found a relationship at continental scales between soil fertility and broad trends in forest structure and function. Little is known at regional scales, however, about how discrete patterns in forest structure or functional attributes map onto underlying edaphic or geological patterns. We collected airborne LiDAR (Light Detection and Ranging) data and VSWIR (Visible to Shortwave Infrared) imaging spectroscopy measurements over 600 km2 of northwestern Amazonian lowland forests. We also established 83 inventories of plant species composition and soil properties, distributed between two widespread geological formations. Using these data, we mapped forest structure and canopy reflectance, and compared them to patterns in plant species composition, soils, and underlying geology. We found that variations in soils and species composition explained up to 70% of variation in canopy height, and corresponded to profound changes in forest vertical profiles. We further found that soils and plant species composition explained more than 90% of the variation in canopy reflectance as measured by imaging spectroscopy, indicating edaphic and compositional control of canopy chemical properties. We last found that soils explained between 30% and 70% of the variation in gap frequency in these forests, depending on the height threshold used to define gaps. Our findings indicate that a relatively small number of edaphic and compositional variables, corresponding to underlying geology, may be responsible for variations in canopy structure and chemistry over large expanses of Amazonian forest.

An Analysis of Student Engagement Patterns and Online Course Outcomes in Wisconsin. Stated Briefly. REL 2016-157

ERIC Educational Resources Information Center

Pazzaglia, Angela M.; Clements, Margaret; Lavigne, Heather J.; Stafford, Erin T.

2016-01-01

This study used administrative data from Wisconsin Virtual School to identify patterns of student engagement in online courses (defined as the amount of time students were logged in to their course each week and how this varied over time). The study also examined whether the patterns were associated with course outcomes (defined as the percentage…

Dissimilarity representations in lung parenchyma classification

NASA Astrophysics Data System (ADS)

Sørensen, Lauge; de Bruijne, Marleen

2009-02-01

A good problem representation is important for a pattern recognition system to be successful. The traditional approach to statistical pattern recognition is feature representation. More specifically, objects are represented by a number of features in a feature vector space, and classifiers are built in this representation. This is also the general trend in lung parenchyma classification in computed tomography (CT) images, where the features often are measures on feature histograms. Instead, we propose to build normal density based classifiers in dissimilarity representations for lung parenchyma classification. This allows for the classifiers to work on dissimilarities between objects, which might be a more natural way of representing lung parenchyma. In this context, dissimilarity is defined between CT regions of interest (ROI)s. ROIs are represented by their CT attenuation histogram and ROI dissimilarity is defined as a histogram dissimilarity measure between the attenuation histograms. In this setting, the full histograms are utilized according to the chosen histogram dissimilarity measure. We apply this idea to classification of different emphysema patterns as well as normal, healthy tissue. Two dissimilarity representation approaches as well as different histogram dissimilarity measures are considered. The approaches are evaluated on a set of 168 CT ROIs using normal density based classifiers all showing good performance. Compared to using histogram dissimilarity directly as distance in a emph{k} nearest neighbor classifier, which achieves a classification accuracy of 92.9%, the best dissimilarity representation based classifier is significantly better with a classification accuracy of 97.0% (text{emph{p" border="0" class="imgtopleft"> = 0.046).

The unpredictability of lymphatic drainage from the ear in melanoma patients, and its implications for management.

PubMed

Peach, Howard S; van der Ploeg, Augustinus P T; Haydu, Lauren E; Stretch, Jonathan R; Shannon, Kerwin F; Uren, Roger F; Thompson, John F

2013-05-01

The ear is known to have variable lymphatic drainage. The purpose of this study was to define better the lymphatic drainage patterns of the ear by correlating the location of primary tumors, classified according to the embryologically derived anatomical subunits of the ear, with their mapped sentinel nodes (SNs) identified by lymphoscintigraphy (LS). Lymphatic drainage data for patients with a primary melanoma of the ear were reviewed and correlated with the precise primary melanoma site. Between 1993 and 2010, LS was performed in 111 patients with a primary melanoma on the ear, identifying 281 SNs in 195 lymph node (LN) fields. The mean numbers of SNs and LN fields identified by LS per patient were 2.65 and 1.76. SN biopsy was performed in 71 patients (64 %). The mean number of SNs removed was 2.36. The 111 ear melanomas were mostly located on the helical rim (55 %), followed by the lobule (24.3 %). The five different primary ear sites drained mainly to SNs in level CII, level CV and the preauricular region. Drainage was most often to level CII (36.4 %). Drainage to the contralateral neck was not observed. Lymphatic drainage of the ear has no predictable pattern and can be to SNs anywhere in the ipsilateral neck. Most commonly drainage is to cervical level II and the preauricular and postauricular LN fields. LS defines the lymphatic drainage pattern in individual melanoma patients and is essential for accurate SN identification and reliable SN biopsy.

The Time Course of Segmentation and Cue-Selectivity in the Human Visual Cortex

PubMed Central

Appelbaum, Lawrence G.; Ales, Justin M.; Norcia, Anthony M.

2012-01-01

Texture discontinuities are a fundamental cue by which the visual system segments objects from their background. The neural mechanisms supporting texture-based segmentation are therefore critical to visual perception and cognition. In the present experiment we employ an EEG source-imaging approach in order to study the time course of texture-based segmentation in the human brain. Visual Evoked Potentials were recorded to four types of stimuli in which periodic temporal modulation of a central 3° figure region could either support figure-ground segmentation, or have identical local texture modulations but not produce changes in global image segmentation. The image discontinuities were defined either by orientation or phase differences across image regions. Evoked responses to these four stimuli were analyzed both at the scalp and on the cortical surface in retinotopic and functional regions-of-interest (ROIs) defined separately using fMRI on a subject-by-subject basis. Texture segmentation (tsVEP: segmenting versus non-segmenting) and cue-specific (csVEP: orientation versus phase) responses exhibited distinctive patterns of activity. Alternations between uniform and segmented images produced highly asymmetric responses that were larger after transitions from the uniform to the segmented state. Texture modulations that signaled the appearance of a figure evoked a pattern of increased activity starting at ∼143 ms that was larger in V1 and LOC ROIs, relative to identical modulations that didn't signal figure-ground segmentation. This segmentation-related activity occurred after an initial response phase that did not depend on the global segmentation structure of the image. The two cue types evoked similar tsVEPs up to 230 ms when they differed in the V4 and LOC ROIs. The evolution of the response proceeded largely in the feed-forward direction, with only weak evidence for feedback-related activity. PMID:22479566

Regional variation in antibiotic prescribing among medicare part D enrollees, 2013.

PubMed

Arizpe, Andre; Reveles, Kelly R; Aitken, Samuel L

2016-12-09

Antibiotics are among the most widely prescribed medications. The geographic variation in antibiotic prescribing patterns and associated costs among Medicare Part D recipients have not been described. The purpose of this study was to assess the regional variation in antibiotic prescriptions and costs among Medicare Part D enrollees in 2013. Retrospective cohort review of all Medicare Part D enrollees in 2013, using the Medicare Provider Utilization and Payment Data: Part D Prescriber Public Use File. All original or refill prescription claims for antibiotics as listed in the Part D Prescriber Public Use File were included. Our primary outcomes were total antibiotic claims and antibiotic cost per Medicare Part D Enrollee. Data were analyzed descriptively by state and by geographic region as defined by the United States Census Bureau. Antibiotic claims were described overall and by antibiotic class. Over 54 million outpatient antibiotic claims were filed for Part D enrollees in 2013, representing more than $1.5 billion in total antibiotic expenditures. Antibiotic use was highest in the South (1,623 claims/1,000 enrollees), followed by the Midwest (1,401 claims/1,000 enrollees), Northeast (1,366 claims/1,000 enrollees), and West (1,292 claims/1,000 enrollees). Average antibiotic costs per enrollee in each region were as follows: South $46.58, Northeast $43.70, Midwest $40.54, and West $36.42. Fluoroquinolones were the most commonly prescribed class overall (12.2 million claims). Antibiotic use among elderly Medicare enrollees in the United States was highest in the South region. Fluoroquinolones were the most common antibiotics used in all regions. These patterns could be utilized in the development of targeted antimicrobial stewardship efforts.

Coupling between populations of copepod taxa within an estuarine ecosystem and the adjacent offshore regions

NASA Astrophysics Data System (ADS)

McGinty, N.; Johnson, M. P.; Power, A. M.

2012-07-01

Population dynamics in open systems are complicated by the interactions of local demography and local environmental forcing with processes occurring at larger scales. A local system such as an estuary or bay may contain a zooplankton population that effectively becomes independent of regional dynamics or the local dynamics may be closely coupled to a broader scale pattern. As an alternative, the details of migration and advection may mean that dynamics in a local system are coupled to other specific areas rather than tracking the overall dynamics at a larger scale. We used a reconstructed time series (1973-1987) for copepod taxa to examine the extent to which zooplankton dynamics in Galway Bay reflect processes in broader areas of the NE Atlantic. Continuous Plankton Recorder (CPR) counts were used to establish time series for nine offshore ecoregions, with the regions themselves defined using underlying patterns of chlorophyll variability. The open nature of Galway Bay was reflected in strong associations between bay zooplankton counts and offshore CPR data in a majority of cases (7/10). For each zooplankton taxon, there were large differences among regions in the degree of association with Galway Bay time series. Akaike weights indicated that one ecoregion tended to be the dominant link for each taxon. This indicates that the zooplankton of the Bay reflect more than the local modification of a regional signal and that different zooplankton in the bay may have separate source regions. The data from Galway Bay also fall within a 'sampling shadow' of the CPR. Later years of the time series showed evidence for changes in phenology, with spring zooplankton peaks generally occurring earlier in the year for smaller species.

Development of adaptive liquid microlenses and microlens arrays

NASA Astrophysics Data System (ADS)

Berry, Shaun R.; Stewart, Jason B.; Thorsen, Todd A.; Guha, Ingrid

2013-03-01

We report on the development of sub-millimeter size adaptive liquid microlenses and microlens arrays using two immiscible liquids to form individual lenses. Microlenses and microlens arrays having aperture diameters as small as 50 microns were fabricated on a planar quartz substrate using patterned hydrophobic/hydrophilic regions. Liquid lenses were formed by a self-assembled oil dosing process that created well-defined lenses having a high fill factor. Variable focus was achieved by controlling the lens curvature through electrowetting. Greater than 70° of contact angle change was achieved with less than 20 volts, which results in a large optical power dynamic range.

Urban and regional land use analysis: CARETS and Census Cities experiment package. [Pennsylvania, New Jersey, Delaware, Maryland, Virginia, District of Columbia, Washington, California

NASA Technical Reports Server (NTRS)

Alexander, R. (Principal Investigator); Lins, H. F., Jr.; Wray, J. R.

1974-01-01

The author has identified the following significant results. A number of likely applications and follow-on analyses are suggested by the census cities evaluation of ERTS-1 and Skylab data. Some of these applications are: (1) estimate water use requirements; (2) define urban expansion; (3) document the pattern of residential development and assess quality of residential environment: (4) project future population densities, and estimate changes in population distribution between censuses; (5) assess environmental impact resulting from gradual as well as catastrophic changes.

Population structure of humpback whales in the western and central South Pacific Ocean as determined by vocal exchange among populations.

PubMed

Garland, Ellen C; Goldizen, Anne W; Lilley, Matthew S; Rekdahl, Melinda L; Garrigue, Claire; Constantine, Rochelle; Hauser, Nan Daeschler; Poole, M Michael; Robbins, Jooke; Noad, Michael J

2015-08-01

For cetaceans, population structure is traditionally determined by molecular genetics or photographically identified individuals. Acoustic data, however, has provided information on movement and population structure with less effort and cost than traditional methods in an array of taxa. Male humpback whales (Megaptera novaeangliae) produce a continually evolving vocal sexual display, or song, that is similar among all males in a population. The rapid cultural transmission (the transfer of information or behavior between conspecifics through social learning) of different versions of this display between distinct but interconnected populations in the western and central South Pacific region presents a unique way to investigate population structure based on the movement dynamics of a song (acoustic) display. Using 11 years of data, we investigated an acoustically based population structure for the region by comparing stereotyped song sequences among populations and years. We used the Levenshtein distance technique to group previously defined populations into (vocally based) clusters based on the overall similarity of their song display in space and time. We identified the following distinct vocal clusters: western cluster, 1 population off eastern Australia; central cluster, populations around New Caledonia, Tonga, and American Samoa; and eastern region, either a single cluster or 2 clusters, one around the Cook Islands and the other off French Polynesia. These results are consistent with the hypothesis that each breeding aggregation represents a distinct population (each occupied a single, terminal node) in a metapopulation, similar to the current understanding of population structure based on genetic and photo-identification studies. However, the central vocal cluster had higher levels of song-sharing among populations than the other clusters, indicating that levels of vocal connectivity varied within the region. Our results demonstrate the utility and value of using culturally transmitted vocal patterns as a way of defining connectivity to infer population structure. We suggest vocal patterns be incorporated by the International Whaling Commission in conjunction with traditional methods in the assessment of structure. © 2015, Society for Conservation Biology.

Patterns of Failure After Radical Cystectomy for pT3-4 Bladder Cancer: Implications for Adjuvant Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reddy, Abhinav V.; Pariser, Joseph J.; Pearce, Shane M.

2016-04-01

Purpose: In patients with muscle-invasive bladder cancer, local-regional failure (LF) has been reported to occur in up to 20% of patients following radical cystectomy. The goals of this study were to describe patterns of LF, as well as assess factors associated with LF in a cohort of patients with pT3-4 bladder cancer. This information may have implications towards the use of adjuvant radiation therapy. Methods and Materials: Patients with pathologic T3-4 N0-1 bladder cancer were examined from an institutional radical cystectomy database. Preoperative demographics and pathologic characteristics were examined. Outcomes included overall survival and LF. Local-regional failures were defined usingmore » follow-up imaging reports and scans, and the locations of LF were characterized. Variables were tested by univariate and multivariate analysis for association with LF and overall survival. Results: A total of 334 patients had pT3-4 and N0-1 disease after radical cystectomy and bilateral pelvic lymph node dissection. Of these, 46% received perioperative chemotherapy. The median age was 71 years old, and median follow-up was 11 months. On univariate analysis, margin status, pT stage, and pN stage, were all associated with LF (P<.05), however, on multivariate analysis, only pT and pN stages were significantly associated with LF (P<.05). Three strata of risk were defined, including low-risk patients with pT3N0 disease, intermediate-risk patients with pT3N1 or pT4N0 disease, and high-risk patients with pT4N1 disease, who had a 2-year incidence of LF of 12%, 33%, and 72%, respectively. The most common sites of pelvic relapse included the external and internal iliac lymph nodes (LNs) and obturator LN regions. Notably, 34% of patients with LF had local-regional only disease at the time of recurrence. Conclusions: Patients with pT4 or N1 disease have a 2-year risk of LF that exceeds 30%. These patients may be the most likely to benefit from local adjuvant therapies.« less

Different Patterns of the Urban Heat Island Intensity from Cluster Analysis

NASA Astrophysics Data System (ADS)

Silva, F. B.; Longo, K.

2014-12-01

This study analyzes the different variability patterns of the Urban Heat Island intensity (UHII) in the Metropolitan Area of Rio de Janeiro (MARJ), one of the largest urban agglomerations in Brazil. The UHII is defined as the difference in the surface air temperature between the urban/suburban and rural/vegetated areas. To choose one or more stations that represent those areas we used the technique of cluster analysis on the air temperature observations from 14 surface weather stations in the MARJ. The cluster analysis aims to classify objects based on their characteristics, gathering similar groups. The results show homogeneity patterns between air temperature observations, with 6 homogeneous groups being defined. Among those groups, one might be a natural choice for the representative urban area (Central station); one corresponds to suburban area (Afonsos station); and another group referred as rural area is compound of three stations (Ecologia, Santa Cruz and Xerém) that are located in vegetated regions. The arithmetic mean of temperature from the three rural stations is taken to represent the rural station temperature. The UHII is determined from these homogeneous groups. The first UHII is estimated from urban and rural temperature areas (Case 1), whilst the second UHII is obtained from suburban and rural temperature areas (Case 2). In Case 1, the maximum UHII occurs in two periods, one in the early morning and the other at night, while the minimum UHII occurs in the afternoon. In Case 2, the maximum UHII is observed during afternoon/night and the minimum during dawn/early morning. This study demonstrates that the stations choice reflects different UHII patterns, evidencing that distinct behaviors of this phenomenon can be identified.

Defining functional groups based on running kinematics using Self-Organizing Maps and Support Vector Machines.

PubMed

Hoerzer, Stefan; von Tscharner, Vinzenz; Jacob, Christian; Nigg, Benno M

2015-07-16

A functional group is a collection of individuals who react in a similar way to a specific intervention/product such as a sport shoe. Matching footwear features to a functional group can possibly enhance footwear-related comfort, improve running performance, and decrease the risk of movement-related injuries. To match footwear features to a functional group, one has to first define the different groups using their distinctive movement patterns. Therefore, the main objective of this study was to propose and apply a methodological approach to define functional groups with different movement patterns using Self-Organizing Maps and Support Vector Machines. Further study objectives were to identify differences in age, gender and footwear-related comfort preferences between the functional groups. Kinematic data and subjective comfort preferences of 88 subjects (16-76 years; 45 m/43 f) were analysed. Eight functional groups with distinctive movement patterns were defined. The findings revealed that most of the groups differed in age or gender. Certain functional groups differed in their comfort preferences and, therefore, had group-specific footwear requirements to enhance footwear-related comfort. Some of the groups, which had group-specific footwear requirements, did not show any differences in age or gender. This is important because when defining functional groups simply using common grouping criteria like age or gender, certain functional groups with group-specific movement patterns and footwear requirements might not be detected. This emphasises the power of the proposed pattern recognition approach to automatically define groups by their distinctive movement patterns in order to be able to address their group-specific product requirements. Copyright © 2015 Elsevier Ltd. All rights reserved.

The tropospheric biennial oscillation defined by a biennial mode of sea surface temperature and its impact on the atmospheric circulation and precipitation in the tropical eastern Indo-western Pacific region

NASA Astrophysics Data System (ADS)

Kim, Jinju; Kim, Kwang-Yul

2016-10-01

Temporal and spatial patterns of anomalous atmospheric circulation and precipitation over the Indo-Pacific region are analyzed in conjunction with the Tropospheric Biennial Oscillation as represented by the biennial mode of sea surface temperature anomalies (SSTA). The biennial components of key variables are identified independently of other variability via CSEOF analysis. Then, its impact on the Asian-Australian monsoon is examined. The biennial mode exhibits a seasonally distinctive atmospheric response over the tropical eastern Indo-western Pacific (EIWP) region (90°-150°E, 20°S-20°N). In boreal summer, local meridional circulation is a distinguishing characteristic over the tropical EIWP region, whereas a meridionally expanded branch of intensified zonal circulation develops in austral summer. Temporally varying evolution and distinct timing of SSTA phase transition in the Indian and Pacific Oceans is considered a main factor for this variation of circulation in the tropical EIWP region. The impact of the biennial mode is not the same between the two seasons, with different impacts over ocean areas in Asian monsoon and Australian monsoon regions.

An improved neutral landscape model for recreating real landscapes and generating landscape series for spatial ecological simulations.

PubMed

van Strien, Maarten J; Slager, Cornelis T J; de Vries, Bauke; Grêt-Regamey, Adrienne

2016-06-01

Many studies have assessed the effect of landscape patterns on spatial ecological processes by simulating these processes in computer-generated landscapes with varying composition and configuration. To generate such landscapes, various neutral landscape models have been developed. However, the limited set of landscape-level pattern variables included in these models is often inadequate to generate landscapes that reflect real landscapes. In order to achieve more flexibility and variability in the generated landscapes patterns, a more complete set of class- and patch-level pattern variables should be implemented in these models. These enhancements have been implemented in Landscape Generator (LG), which is a software that uses optimization algorithms to generate landscapes that match user-defined target values. Developed for participatory spatial planning at small scale, we enhanced the usability of LG and demonstrated how it can be used for larger scale ecological studies. First, we used LG to recreate landscape patterns from a real landscape (i.e., a mountainous region in Switzerland). Second, we generated landscape series with incrementally changing pattern variables, which could be used in ecological simulation studies. We found that LG was able to recreate landscape patterns that approximate those of real landscapes. Furthermore, we successfully generated landscape series that would not have been possible with traditional neutral landscape models. LG is a promising novel approach for generating neutral landscapes and enables testing of new hypotheses regarding the influence of landscape patterns on ecological processes. LG is freely available online.

Directed midbrain and spinal cord neurogenesis from pluripotent stem cells to model development and disease in a dish

PubMed Central

Allodi, Ilary; Hedlund, Eva

2014-01-01

Induction of specific neuronal fates is restricted in time and space in the developing CNS through integration of extrinsic morphogen signals and intrinsic determinants. Morphogens impose regional characteristics on neural progenitors and establish distinct progenitor domains. Such domains are defined by unique expression patterns of fate determining transcription factors. These processes of neuronal fate specification can be recapitulated in vitro using pluripotent stem cells. In this review, we focus on the generation of dopamine neurons and motor neurons, which are induced at ventral positions of the neural tube through Sonic hedgehog (Shh) signaling, and defined at anteroposterior positions by fibroblast growth factor (Fgf) 8, Wnt1, and retinoic acid (RA). In vitro utilization of these morphogenic signals typically results in the generation of multiple neuronal cell types, which are defined at the intersection of these signals. If the purpose of in vitro neurogenesis is to generate one cell type only, further lineage restriction can be accomplished by forced expression of specific transcription factors in a permissive environment. Alternatively, cell-sorting strategies allow for selection of neuronal progenitors or mature neurons. However, modeling development, disease and prospective therapies in a dish could benefit from structured heterogeneity, where desired neurons are appropriately synaptically connected and thus better reflect the three-dimensional structure of that region. By modulating the extrinsic environment to direct sequential generation of neural progenitors within a domain, followed by self-organization and synaptic establishment, a reductionist model of that brain region could be created. Here we review recent advances in neuronal fate induction in vitro, with a focus on the interplay between cell intrinsic and extrinsic factors, and discuss the implications for studying development and disease in a dish. PMID:24904255

Directed midbrain and spinal cord neurogenesis from pluripotent stem cells to model development and disease in a dish.

PubMed

Allodi, Ilary; Hedlund, Eva

2014-01-01

Induction of specific neuronal fates is restricted in time and space in the developing CNS through integration of extrinsic morphogen signals and intrinsic determinants. Morphogens impose regional characteristics on neural progenitors and establish distinct progenitor domains. Such domains are defined by unique expression patterns of fate determining transcription factors. These processes of neuronal fate specification can be recapitulated in vitro using pluripotent stem cells. In this review, we focus on the generation of dopamine neurons and motor neurons, which are induced at ventral positions of the neural tube through Sonic hedgehog (Shh) signaling, and defined at anteroposterior positions by fibroblast growth factor (Fgf) 8, Wnt1, and retinoic acid (RA). In vitro utilization of these morphogenic signals typically results in the generation of multiple neuronal cell types, which are defined at the intersection of these signals. If the purpose of in vitro neurogenesis is to generate one cell type only, further lineage restriction can be accomplished by forced expression of specific transcription factors in a permissive environment. Alternatively, cell-sorting strategies allow for selection of neuronal progenitors or mature neurons. However, modeling development, disease and prospective therapies in a dish could benefit from structured heterogeneity, where desired neurons are appropriately synaptically connected and thus better reflect the three-dimensional structure of that region. By modulating the extrinsic environment to direct sequential generation of neural progenitors within a domain, followed by self-organization and synaptic establishment, a reductionist model of that brain region could be created. Here we review recent advances in neuronal fate induction in vitro, with a focus on the interplay between cell intrinsic and extrinsic factors, and discuss the implications for studying development and disease in a dish.

Differences in photoreceptor recovery among patients and between different parts of the posterior pole in Vogt–Koyanagi–Harada disease

PubMed Central

Zhou, M; Gu, R P; Sun, Z; Jiang, C H; Chang, Q; Xu, G Z

2018-01-01

Purpose To investigate the recovery of photoreceptors following the treatment in Vogt–Koyanagi–Harada (VKH) disease. Patients and methods This was a retrospective study. We enrolled 28 patients with VKH (56 eyes). The clinical and optical coherence tomography (OCT) findings were recorded for 12 months after treatment. The patterns of photoreceptor recovery on OCT were defined: pattern F group=Foveal photoreceptor recovery visible first; pattern E group=Extrafoveal photoreceptor recovery visible first; and pattern S group=Simultaneous foveal and extrafoveal photoreceptor recovery. Results Photoreceptor recovery varied in different parts of the fundus among patients. Among the 56 eyes, the ellipsoid zone (EZ) recovery of 10 eyes and the interdigitation zone (IZ) recovery of 17 eyes belonged to pattern F group. In most eyes (46 eyes for EZ and 26 eyes for IZ), the recovery of these structures were pattern S. Only in 10 eyes, the recovery of IZ was pattern E. The different patterns of recovery correlated with how promptly the patients had been treated and with the anatomical and visual outcomes at 12 months. Patients in pattern F group were characterized by delayed treatment, delayed recovery of EZ or IZ, and a less favourable prognosis at 12 months relative to other patients, while those in pattern E group had the most prompt treatment and recovery as well as a more favourable outcome at 12 months. Conclusions In VKH patients with delayed treatment, foveal photoreceptors tended to recover more rapidly than photoreceptors in other regions. PMID:29148525

Tectonic geomorphology of the New Madrid seismic zone based on imaging of digital topographic data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mayer, L.

1993-03-01

Topographic analysis using digital elevation data of the New Madrid region focuses on topographic features that occur at several spatial scales and can be used to delineate distinct anomalies. In this region, topographic anomalies occur as domal or elongate uplifts and bowl-shaped depressions approximately 1--10 km in size, topographic lineaments, and differences in topographic blocking across 50 km long boundaries. In order to fully explain these topographic anomalies, tectonic processes may be required. Imaging is based on digital topographic data from USGS 30 arc-second, 3 arc-second, and 30 m resolutions. Imaging of these data uses standard imaging processing techniques tomore » examine topography within the contexts of geomorphological hypothesis testing. A good example is the use of thresholding to highlight areas of unusually high elevation given the hypothesis of fluvial landscape architecture. Thresholding delineates topographic features such as the Tiptonville dome which is strongly believed to be tectonic in origin. To determine the pattern of topographic blocking, defined as a pattern that topography assumes when constrained by active forces other than erosion alone, low frequency passing spatial convolutions are used as filters and the resulting data are sliced into blocks according to pseudoelevations that produce a stable block pattern. The resultant blocks are analyzed according to its structural pattern of block size and block orientation. This analysis suggests that a topographic boundary cuts across the Mississippi embayment from near the Newport pluton on the west, to the area south of Memphis on east.« less

Deep Structure of the Earth and Concentration of Metals in the Lithosphere: A Geodynamic Approach

NASA Technical Reports Server (NTRS)

Taylor, Patrick T.; Kutina, J.; Pei, R.

2004-01-01

A discussion of and introduction to satellite-altitude geopotential fields studies and their interpretation with emphasis on results from metalliferous regions will be given. The magnetic and gravimetric measurements from satellite altitudes show heterogeneity in deeper parts of the lithosphere. These patterns of magnetic anomalies do not only reveal the largest iron ore deposits such as Kiruna, Sweden and Kursk, Russia, but also linear features indicating structural discontinuities. Changes of magnetic amplitude of these patterns are caused by intersecting transverse fractures localizing magmatism and concentration of metals. The role of trans-regional mantle-rooted structural discontinuities in the concentration of metals will be discussed and a new type of mineral prognosis map will be presented. Deep-rooted structural discontinuities, defined by combination of geological and geophysical criteria, with spacing of several hundred kilometers, reveal a quite uniform pattern in the deeper parts of the lithosphere. As these structures provide favorable pathways for the ascent of heat, magmas and ore-forming fluids, their recognition is of crucial importance and can be used in the compilation of a new type of mineral prognosis map. Examples are shown from the United States, Canada, China, Burma, South America, Europe and Australia. The European example includes a pattern of east west trending structural discontinuities or belts and their junction with the NW-trending Tornqvist-Teisseyre Line. The Upper Silesian-Cracovian Zn-Pb district occurs along one of the latitudinal belts. Leslaw Teper of the University of Silesia has been invited to show the fractures in crystalline basement beneath the sediments hosting the Zn-Pb ores.

QPA-CLIPS: A language and representation for process control

NASA Technical Reports Server (NTRS)

Freund, Thomas G.

1994-01-01

QPA-CLIPS is an extension of CLIPS oriented towards process control applications. Its constructs define a dependency network of process actions driven by sensor information. The language consists of three basic constructs: TASK, SENSOR, and FILTER. TASK's define the dependency network describing alternative state transitions for a process. SENSOR's and FILTER's define sensor information sources used to activate state transitions within the network. Deftemplate's define these constructs and their run-time environment is an interpreter knowledge base, performing pattern matching on sensor information and so activating TASK's in the dependency network. The pattern matching technique is based on the repeatable occurrence of a sensor data pattern. QPA-CIPS has been successfully tested on a SPARCStation providing supervisory control to an Allen-Bradley PLC 5 controller driving molding equipment.

BI-31ANALYSIS AND QUANTIFICATION OF MULTIPLE ANTIGEN EXPRESSION IN GLIOBLASTOMA

PubMed Central

Weng, Lihong; Zhai, Yubo; D'Apuzzo, Massimo; Badie, Behnam; Forman, Stephen J.; Barish, Michael; Brown, Christine E.

2014-01-01

Glioblastoma (GBM), one of the most common and fatal types of brain tumor, is marked by significant antigenic heterogeneity. Identification and quantification of tumor related antigens in the context of GBM tissue is an essential step towards developing antigen- targeted therapies. Immunohistochemistry (IHC) on formalin-fixed paraffin embedded (FFPE) clinical specimens is a valuable technique for evaluating antigen expression in large study cohorts. To overcome the limitations of manual semi-quantitative scoring and subjectivity in the evaluation of IHC staining, we analyzed and quantified multiple antigens across entire tumor sections using Image Pro Premier v9.1 (DAB plug-in). For each slide, dense tumor regions (DTRs, tumor cells >60%), tumor infiltration regions (TIRs, tumor cells <50%) and pseudopalisading necrosis regions (PPNs) were defined from HE section by a neuropathologist. We quantified the expression of tumor-associated antigens IL13Rα2, HER2, EGFR and the proliferation marker Ki67 within these defined regions for 44 brain tumor samples (35 stage IV and 9 stage III). Our results demonstrate the heterogeneous expression patterns of IL13Rα2, HER2 and EGFR in GBMs. For example, in dense tumor regions 52%, 61% and 77% of samples showed IL13Rα2, HER2 or EGFR positivity, respectively. In correlation studies, 25% of samples were triple positive, 11% of samples showed double positivity for IL13Rα2 and HER2 or IL13Rα2 and EGFR, and 25% of samples were double positive of EGFR and HER2. Less than 7% of samples were negative for all three antigens. Interestingly, a higher percentage of samples showed triple positive expression in PPN regions (43%) versus the DTR (25%) and TIR (25%) regions. Also, Ki67 positivity was higher in PPN and DTR regions. In this study we developed methods for combining pathological annotations with DAB-capturing software, which allowed us to quantify protein expression in a more precise, consistent and efficient manner.

Resting-state brain activity in the motor cortex reflects task-induced activity: A multi-voxel pattern analysis.

PubMed

Kusano, Toshiki; Kurashige, Hiroki; Nambu, Isao; Moriguchi, Yoshiya; Hanakawa, Takashi; Wada, Yasuhiro; Osu, Rieko

2015-08-01

It has been suggested that resting-state brain activity reflects task-induced brain activity patterns. In this study, we examined whether neural representations of specific movements can be observed in the resting-state brain activity patterns of motor areas. First, we defined two regions of interest (ROIs) to examine brain activity associated with two different behavioral tasks. Using multi-voxel pattern analysis with regularized logistic regression, we designed a decoder to detect voxel-level neural representations corresponding to the tasks in each ROI. Next, we applied the decoder to resting-state brain activity. We found that the decoder discriminated resting-state neural activity with accuracy comparable to that associated with task-induced neural activity. The distribution of learned weighted parameters for each ROI was similar for resting-state and task-induced activities. Large weighted parameters were mainly located on conjunctive areas. Moreover, the accuracy of detection was higher than that for a decoder whose weights were randomly shuffled, indicating that the resting-state brain activity includes multi-voxel patterns similar to the neural representation for the tasks. Therefore, these results suggest that the neural representation of resting-state brain activity is more finely organized and more complex than conventionally considered.

Tools for neuroanatomy and neurogenetics in Drosophila

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pfeiffer, Barret D.; Jenett, Arnim; Hammonds, Ann S.

2008-08-11

We demonstrate the feasibility of generating thousands of transgenic Drosophila melanogaster lines in which the expression of an exogenous gene is reproducibly directed to distinct small subsets of cells in the adult brain. We expect the expression patterns produced by the collection of 5,000 lines that we are currently generating to encompass all neurons in the brain in a variety of intersecting patterns. Overlapping 3-kb DNA fragments from the flanking noncoding and intronic regions of genes thought to have patterned expression in the adult brain were inserted into a defined genomic location by site-specific recombination. These fragments were then assayedmore » for their ability to function as transcriptional enhancers in conjunction with a synthetic core promoter designed to work with a wide variety of enhancer types. An analysis of 44 fragments from four genes found that >80% drive expression patterns in the brain; the observed patterns were, on average, comprised of <100 cells. Our results suggest that the D. melanogaster genome contains >50,000 enhancers and that multiple enhancers drive distinct subsets of expression of a gene in each tissue and developmental stage. We expect that these lines will be valuable tools for neuroanatomy as well as for the elucidation of neuronal circuits and information flow in the fly brain.« less

Old but Still Relevant: High Resolution Electrophoresis and Immunofixation in Multiple Myeloma.

PubMed

Misra, Aroonima; Mishra, Jyoti; Chandramohan, Jagan; Sharma, Atul; Raina, Vinod; Kumar, Rajive; Soni, Sushant; Chopra, Anita

2016-03-01

High resolution electrophoresis (HRE) and immunofixation (IFX) of serum and urine are integral to the diagnostic work-up of multiple myeloma. Unusual electrophoresis patterns are common and may be misinterpreted. Though primarily the responsibility of the hematopathologist, clinicians who are responsible for managing myelomas may benefit from knowledge of these. In this review article we intend to discuss the patterns and importance of electrophoresis in present day scenario. Patterns of HRE and IFX seen in our laboratory over the past 15 years were studied. Monoclonal proteins are seen on HRE as sharply defined bands, sometimes two, lying from γ- to α-globulin regions on a background of normal, increased or decreased polyclonal γ-globulins, showing HRE to be a rapid and dependable method of detecting M-protein in serum or urine. Immunofixation complements HRE and due to its greater sensitivity, is able to pick up small or light chain bands, not apparent on electrophoresis, including biclonal disease even when electrophoresis shows only one M-band. Special features liable to misinterpretation are discussed. Familiarity with the interpretation of the varied patterns seen in health and disease is essential for providing dependable laboratory support in the management of multiple myeloma.

Assessing the role of Climate Variability in the recent evolution of coastlines in southern Italy

NASA Astrophysics Data System (ADS)

Di Paola, Gianluigi; Atkinson, David; Rosskopf, Carmen M.; Walker, Ian

2016-04-01

During the last century, Climatic Variability (CV) and change effects have generated a discernable impact on the world's coasts, most notably through changes in the frequency and/or magnitude of storm surges, flooding, coastal erosion and sea-level rise. This study explores CV signals and coastal responses along a 36 km stretch of coast in the Molise region of southern Italy on the Central Adriatic Sea. Two dominant signals of CV in the Mediterranean region of Europe are characterized by the North Atlantic Oscillation (NAO) and the East Atlantic-West Russia (EAWR) patterns. The NAO is the leading mode of CV in the North Atlantic region and periods with positive NAO index values are typically associated with above average wind speeds across the mid-latitudes of the Atlantic and western Europe, with anomalously northerly flows across the Mediterranean region and enhanced trade winds over the sub-tropical North Atlantic. Although NAO is one of the most prominent patterns in all seasons, its relative role in regulating the variability of the European climate during non-winter months is not as clear as for the winter season. In contrast, the EAWR exerts strong influence on precipitation in the Mediterranean region such that, during the negative phase of EAWR, wetter conditions prevail across central Europe and the Mediterranean region, with precipitation extremes often occurring during these periods. This study examines the effects of NAO and EAWR on coastline response in the Molise region, which has a microtidal regime (ordinary tidal excursions of 30-40 cm). GIS analysis of shoreline changes from historical aerial photography from 1954-2011 was performed and 20 years (1989-2008) of wave data were analysed from the nearby Ortona buoy to define trends and extreme event occurrence in the wave climate in the study area. Finally, statistical associations between NAO, EAWR, and other CV indices of possible influence (e.g. Arctic Oscillation, Scandinavia Pattern, or the East Atlantic pattern) and shoreline position changes were explored in order to identify linkages between CV forcing and coastal response in this region. The study demonstrates that the recent evolution of the Molise coastline is responding to changes in the wave climate and increases in the frequency and intensity of storm surges in recent years. Coastal response in the region is also strongly controlled by engineering interventions, such as backwater structures and groynes (almost the 75% of coastline is characterized by offshore defenses, above all around Biferno and Trigno mouths and Termoli harbor), and the interaction of the river systems that feed the coastline. This condition may mitigate some of the impacts of CV events that are observed elsewhere along intervening stretches of coast.

Low level moisture from VAS

NASA Technical Reports Server (NTRS)

Hayden, C. M.

1980-01-01

Previous research and current opinion are too pessimistic concerning the capability of defining moisture fields from satellite measurements. The TIROS-N sounder is a close analogue to what will fly on GEOS-D and can be used to investigate the probable capability of VAS. Basically, there are three frequencies applied to sensing moisture in the troposphere. The ability of these three measurements to define the moisture pattern is assessed. It is certainly true that one cannot achieve the detail available with a radiosonde hygristor. Sharp discontinuities cannot be sensed by a passive sounder, especially since the measurement tends to "saturate" with the first moisture layer encountered. However, the satellite measurements demonstrate a high degree of skill in defining the horizontal gradient. Moisture "tongues" and "dry lines" are readily delineated with some, perhaps two layers, of vertical definition. These attributes allow both the calculation of important advective quantities as well as (in concert with the temperature sounding) a gross definition of the vertical stability. The skill is demonstrably commensurate with subsynoptic forecast models and perhaps even to regional scale models.

Computer mapping of LANDSAT data for environmental applications

NASA Technical Reports Server (NTRS)

Rogers, R. H. (Principal Investigator); Mckeon, J. B.; Reed, L. E.; Schmidt, N. F.; Schecter, R. N.

1975-01-01

The author has identified the following significant results. Land cover overlays and maps produced from LANDSAT are providing information on existing land use and resources throughout the 208 study area. The overlays are being used to delineate drainage areas of a predominant land cover type. Information on cover type is also being combined with other pertinent data to develop estimates of sediment and nutrients flows from the drainage area. The LANDSAT inventory of present land cover together with population projects is providing a basis for developing maps of anticipated land use patterns required to evaluate impact on water quality which may result from these patterns. Overlays of forest types were useful for defining wildlife habitat and vegetational resources in the region. LANDSAT data and computer assisted interpretation was found to be a rapid cost effective procedure for inventorying land cover on a regional basis. The entire 208 inventory which include acquisition of ground truth, LANDSAT tapes, computer processing, and production of overlays and coded tapes was completed within a period of 2 months at a cost of about 0.6 cents per acre, a significant improvement in time and cost over conventional photointerpretation and mapping techniques.

Cortical Entropy, Mutual Information and Scale-Free Dynamics in Waking Mice.

PubMed

Fagerholm, Erik D; Scott, Gregory; Shew, Woodrow L; Song, Chenchen; Leech, Robert; Knöpfel, Thomas; Sharp, David J

2016-10-01

Some neural circuits operate with simple dynamics characterized by one or a few well-defined spatiotemporal scales (e.g. central pattern generators). In contrast, cortical neuronal networks often exhibit richer activity patterns in which all spatiotemporal scales are represented. Such "scale-free" cortical dynamics manifest as cascades of activity with cascade sizes that are distributed according to a power-law. Theory and in vitro experiments suggest that information transmission among cortical circuits is optimized by scale-free dynamics. In vivo tests of this hypothesis have been limited by experimental techniques with insufficient spatial coverage and resolution, i.e., restricted access to a wide range of scales. We overcame these limitations by using genetically encoded voltage imaging to track neural activity in layer 2/3 pyramidal cells across the cortex in mice. As mice recovered from anesthesia, we observed three changes: (a) cortical information capacity increased, (b) information transmission among cortical regions increased and (c) neural activity became scale-free. Our results demonstrate that both information capacity and information transmission are maximized in the awake state in cortical regions with scale-free network dynamics. © The Author 2016. Published by Oxford University Press.

Characterization of inhalable particulate matter, volatile organic compounds and other chemical species measured in urban areas in New Jersey—I. Summertime episodes

NASA Astrophysics Data System (ADS)

Lioy, Paul J.; Daisey, Joan M.; Reiss, Nathan M.; Harkov, Ronald

The 1981 Summer Campaign results of the New Jersey Project on Airborne Toxic Elements and Organic Substances (ATEOS) have been examined for the accumulation of various pollutants during photochemical smog type episodes in Newark, Elizabeth and Camden, N.J. Background data were provided from a rural site in Ringwood, N.J. The interrelationships among inhalable particulate matter (IPM), particulate organic matter (POM), polycyclic aromatic hydrocarbons (PAH), SO 2-4, V, Pb, O 3, volatile organic compounds and alkylating agents are described. In addition, the prevailing synoptic meteorology was examined to characterize the episodes and define situations that significantly affected the accumulation patterns. The concentrations of PAH, toluene, benzene, V and Pb usually varied independently of the episodes indicating primary source contributions. The alkylating agent concentrations appeared to increase in association with episode periods. The results also indicated that 50-60% of the IPM mass in the urban areas was composed of the sum of SO 2-4 and POM. Between site analysis of the SO 2-4 indicated primarily a regional distribution pattern, while the POM appeared to be related to contributions from both local and regional sources.

Intraseasonal variability in subtropical South America as depicted by precipitation data

NASA Astrophysics Data System (ADS)

González, P. L. M.; Vera, C. S.; Liebmann, B.; Kiladis, G.

2008-06-01

Daily precipitation data from three stations in subtropical Argentina are used to describe intraseasonal variability (20 90 days) during the austral summer. This variability is compared locally and regionally with that present in outgoing longwave radiation (OLR) data, in order to evaluate the performance of this variable as a proxy for convection in the region. The influence of the intraseasonal activity of the South American Seesaw (SASS) leading convection pattern on precipitation is also explored. Results show that intraseasonal variability explains a significant portion of summer precipitation variance, with a clear maximum in the vicinity of the SASS subtropical center. Correlation analysis reveals that OLR can explain only a small portion of daily precipitation variability, implying that it does not constitute a proper proxy for precipitation on daily timescales. On intraseasonal timescales, though, OLR is able to reproduce the main features of precipitation variability. The dynamical conditions that promote the development of intraseasonal variability in the region are further analyzed for selected summers. Seasons associated with a strong intraseasonal signal in precipitation variability show distinctive wet/dry intraseasonal periods in daily raw data, and are associated with a well defined SASS-like spatial pattern of convection. During these summers, strong large-scale forcing (such as warm El Niño/Southern Oscillation (ENSO) events and/or tropical intraseasonal convective activity), and Rossby-wave-like circulation anomalies extending across the Pacific Ocean, are also observed.

Potential coastal impacts of contemporary changing climate on South Asian seas states

NASA Astrophysics Data System (ADS)

Gable, F. J.; Aubrey, D. G.

1990-01-01

The threat of man-induced global change on the nations of the South Asian seas region varies from place to place because of differences in exposure to monsoons and stoms, differences in local tectonics and subsidence, and variations in air and sea climates. Because several nations are involved, some having subsistence budgets, and given the cost of deriving independently a comprehensive response to global change, the similarities and differences between national settings must be identified soon. These comparisons will form the basis for local response strategies: the similarities provide a basis for responses similar to that of other nations and the differences provide for local adaptation. That climate change on the South Asian coastal region will have an impact is certain: its economics, environment, and coastal land uses are dominated to a certain extent by this marine influence. The extent of these impacts, however, is uncertain. Accompanying global change will be changes in sea level, differences in storm climate, and altered precipitation patterns; science cannot define today what pattern these changes will take. Because global change is inevitable—although its magnitude, timing, and geographic distribution are unknown—the South Asian seas region should begin the appropriate research and planning studies to set forth a reasoned response to global change, for implementation when scientific evidence for global change is more quantitative.

Evolution of columns, modules, and domains in the neocortex of primates.

PubMed

Kaas, Jon H

2012-06-26

The specialized regions of neocortex of mammals, called areas, have been divided into smaller functional units called minicolumns, columns, modules, and domains. Here we describe some of these functional subdivisions of areas in primates and suggest when they emerged in mammalian evolution. We distinguish several types of these smaller subdivisions. Minicolumns, vertical arrays of neurons that are more densely interconnected with each other than with laterally neighboring neurons, are present in all cortical areas. Classic columns are defined by a repeating pattern of two or more types of cortex distinguished by having different inputs and neurons with different response properties. Sensory stimuli that continuously vary along a stimulus dimension may activate groups of neurons that vary continuously in location, producing "columns" without specific boundaries. Other groups or columns of cortical neurons are separated by narrow septa of fibers that reflect discontinuities in the receptor sheet. Larger regions of posterior parietal cortex and frontal motor cortex are parts of networks devoted to producing different sequences of movements. We distinguish these larger functionally distinct regions as domains. Columns of several types have evolved independently a number of times. Some of the columns found in primates likely emerged with the first primates, whereas others likely were present in earlier ancestors. The sizes and shapes of columns seem to depend on the balance of neuron activation patterns and molecular signals during development.

The 2014 southeast Brazil austral summer drought: regional scale mechanisms and teleconnections

NASA Astrophysics Data System (ADS)

Coelho, Caio A. S.; de Oliveira, Cristiano Prestrelo; Ambrizzi, Tércio; Reboita, Michelle Simões; Carpenedo, Camila Bertoletti; Campos, José Leandro Pereira Silveira; Tomaziello, Ana Carolina Nóbile; Pampuch, Luana Albertani; Custódio, Maria de Souza; Dutra, Lívia Marcia Mosso; Da Rocha, Rosmeri P.; Rehbein, Amanda

2016-06-01

The southeast region of Brazil experienced in austral summer 2014 a major drought event leading to a number of impacts in water availability for human consumption, agricultural irrigation and hydropower production. This study aims to perform a diagnostic analysis of the observed climate conditions during this event, including an inspection of the occurred precipitation anomalies in the context of previous years, and an investigation of possible relationships with sea surface temperatures and atmospheric circulation patterns. The sea surface temperature analysis revealed that the southwestern South Atlantic Ocean region near the coast of southeast Brazil showed strong negative association with precipitation over southeast Brazil, indicating that increased sea temperatures in this ocean region are consistent with reduced precipitation as observed in summer 2014. The circulation analysis revealed prevailing anti-cyclonic anomalies at lower levels (850 hPa) with northerly anomalies to the west of southeast Brazil, channeling moisture from the Amazon towards Paraguay, northern Argentina and southern Brazil, and drier than normal air from the South Atlantic Ocean towards the southeast region of Brazil. This circulation pattern was found to be part of a large-scale teleconnection wave train linked with the subsidence branch of the Walker circulation in the tropical east Pacific, which in turn was generated by an anomalous tropical heat source in north/northeastern Australia. A regional Hadley circulation with an ascending branch to the south of the subsidence branch of the Walker circulation in the tropical east Pacific was identified as an important component connecting the tropical and extratropical circulation. The ascending branch of this Hadley circulation in the south Pacific coincided with an identified Rossby wave source region, which contributed to establishing the extratropical component of the large-scale wave train connecting the south Pacific and the Atlantic region surrounding southeast Brazil. This connection between the Pacific and the Atlantic was confirmed with Rossby ray tracing analyses. The local circulation response was associated to downward air motion (subsidence) over Southeast Brazil, contributing to the expressive negative precipitation anomalies observed during summer 2014, and leading to a major drought event in the historical context. The analysis of atmospheric and oceanic patterns of this event helped defining a schematic framework leading to the observed drought conditions in southeast Brazil, including the involved teleconnections, blocking high pressure, radiative and humidity transport effects.

Unlinking the methylome pattern from nucleotide sequence, revealed by large-scale in vivo genome engineering and methylome editing in medaka fish

PubMed Central

Nakamura, Ryohei; Uno, Ayako; Kumagai, Masahiko; Fukushima, Hiroto S.; Morishita, Shinichi; Takeda, Hiroyuki

2017-01-01

The heavily methylated vertebrate genomes are punctuated by stretches of poorly methylated DNA sequences that usually mark gene regulatory regions. It is known that the methylation state of these regions confers transcriptional control over their associated genes. Given its governance on the transcriptome, cellular functions and identity, genome-wide DNA methylation pattern is tightly regulated and evidently predefined. However, how is the methylation pattern determined in vivo remains enigmatic. Based on in silico and in vitro evidence, recent studies proposed that the regional hypomethylated state is primarily determined by local DNA sequence, e.g., high CpG density and presence of specific transcription factor binding sites. Nonetheless, the dependency of DNA methylation on nucleotide sequence has not been carefully validated in vertebrates in vivo. Herein, with the use of medaka (Oryzias latipes) as a model, the sequence dependency of DNA methylation was intensively tested in vivo. Our statistical modeling confirmed the strong statistical association between nucleotide sequence pattern and methylation state in the medaka genome. However, by manipulating the methylation state of a number of genomic sequences and reintegrating them into medaka embryos, we demonstrated that artificially conferred DNA methylation states were predominantly and robustly maintained in vivo, regardless of their sequences and endogenous states. This feature was also observed in the medaka transgene that had passed across generations. Thus, despite the observed statistical association, nucleotide sequence was unable to autonomously determine its own methylation state in medaka in vivo. Our results apparently argue against the notion of the governance on the DNA methylation by nucleotide sequence, but instead suggest the involvement of other epigenetic factors in defining and maintaining the DNA methylation landscape. Further investigation in other vertebrate models in vivo will be needed for the generalization of our observations made in medaka. PMID:29267279

Spatio-Temporal Variability of Summer Precipitation in Mexico under the Influence of the MJO, with Emphasis on the Bimodal Pattern

NASA Astrophysics Data System (ADS)

Perdigón, J.; Romero-Centeno, R.; Barrett, B.; Ordoñez-Perez, P.

2017-12-01

In many regions of Mexico, precipitation occurs in a very well defined annual cycle with peaks in May-June and September-October and a relative minimum in the middle of the rainy season known as the midsummer drought (MSD). The MJO is the most important mode of intraseasonal variability in the tropics, and, although some studies have shown its evident influence on summer precipitation in Mexico, its role in modulating the bimodal pattern of the summer precipitation cycle is still an open question. The spatio-temporal variability of summer precipitation in Mexico is analyzed through composite analysis according to the phases of the MJO, using the very high resolution CHIRPS precipitation data base and gridded data from the CFSR reanalysis to analyzing the MJO influence on the atmospheric circulation over Mexico and its adjacent basins. In general, during MJO phases 8-2 (4-6) rainfall is above-normal (below-normal), although, in some cases, the summer rainfall patterns during the same phase present considerable differences. The atmospheric circulation shows low (high) troposphere southwesterly (northeasterly) wind anomalies in southern Mexico under wetter conditions compared with climatological patterns, while the inverse pattern is observed under drier conditions. Composite anomalies of several variables also agreed well with those rainfall anomalies. Finally, a MJO complete cycle that reinforces (weakens) the bimodal pattern of summer rainfall in Mexico was found.

Unbalanced-flow, fluid-mixing plug with metering capabilities

NASA Technical Reports Server (NTRS)

England, John Dwight (Inventor); Kelley, Anthony R. (Inventor); Van Buskirk, Paul D. (Inventor)

2009-01-01

A fluid mixer plug has holes formed therethrough such that a remaining portion is closed to fluid flow. The plug's inlet face defines a central circuit region and a ring-shaped region with the ring-shaped region including at least some of the plug's remaining portion so-closed to fluid flow. This remaining portion or closed region at each radius R of the ring shaped region satisfies a radius independent, flow-based relationship. Entry openings are defined in the plug's inlet face in correspondence with the holes. The entry openings define an open flow area at each radius of the ring-shaped region. The open flow area at each such radius satisfies the inverse of the flow-based relationship defining the closed regions of the plug.

Nanotextured Shrink Wrap Superhydrophobic Surfaces by Argon Plasma Etching

PubMed Central

Nokes, Jolie M.; Sharma, Himanshu; Tu, Roger; Kim, Monica Y.; Chu, Michael; Siddiqui, Ali; Khine, Michelle

2016-01-01

We present a rapid, simple, and scalable approach to achieve superhydrophobic (SH) substrates directly in commodity shrink wrap film utilizing Argon (Ar) plasma. Ar plasma treatment creates a stiff skin layer on the surface of the shrink film. When the film shrinks, the mismatch in stiffness between the stiff skin layer and bulk shrink film causes the formation of multiscale hierarchical wrinkles with nano-textured features. Scanning electron microscopy (SEM) images confirm the presence of these biomimetic structures. Contact angle (CA) and contact angle hysteresis (CAH) measurements, respectively, defined as values greater than 150° and less than 10°, verified the SH nature of the substrates. Furthermore, we demonstrate the ability to reliably pattern hydrophilic regions onto the SH substrates, allowing precise capture and detection of proteins in urine. Finally, we achieved self-driven microfluidics via patterning contrasting superhydrophilic microchannels on the SH Ar substrates to induce flow for biosensing. PMID:28773318

Nanotextured Shrink Wrap Superhydrophobic Surfaces by Argon Plasma Etching.

PubMed

Nokes, Jolie M; Sharma, Himanshu; Tu, Roger; Kim, Monica Y; Chu, Michael; Siddiqui, Ali; Khine, Michelle

2016-03-14

We present a rapid, simple, and scalable approach to achieve superhydrophobic (SH) substrates directly in commodity shrink wrap film utilizing Argon (Ar) plasma. Ar plasma treatment creates a stiff skin layer on the surface of the shrink film. When the film shrinks, the mismatch in stiffness between the stiff skin layer and bulk shrink film causes the formation of multiscale hierarchical wrinkles with nano-textured features. Scanning electron microscopy (SEM) images confirm the presence of these biomimetic structures. Contact angle (CA) and contact angle hysteresis (CAH) measurements, respectively, defined as values greater than 150° and less than 10°, verified the SH nature of the substrates. Furthermore, we demonstrate the ability to reliably pattern hydrophilic regions onto the SH substrates, allowing precise capture and detection of proteins in urine. Finally, we achieved self-driven microfluidics via patterning contrasting superhydrophilic microchannels on the SH Ar substrates to induce flow for biosensing.

A species-specific nucleosomal signature defines a periodic distribution of amino acids in proteins.

PubMed

Quintales, Luis; Soriano, Ignacio; Vázquez, Enrique; Segurado, Mónica; Antequera, Francisco

2015-04-01

Nucleosomes are the basic structural units of chromatin. Most of the yeast genome is organized in a pattern of positioned nucleosomes that is stably maintained under a wide range of physiological conditions. In this work, we have searched for sequence determinants associated with positioned nucleosomes in four species of fission and budding yeasts. We show that mononucleosomal DNA follows a highly structured base composition pattern, which differs among species despite the high degree of histone conservation. These nucleosomal signatures are present in transcribed and non-transcribed regions across the genome. In the case of open reading frames, they correctly predict the relative distribution of codons on mononucleosomal DNA, and they also determine a periodicity in the average distribution of amino acids along the proteins. These results establish a direct and species-specific connection between the position of each codon around the histone octamer and protein composition.

Shared temporoparietal dysfunction in dyslexia and typical readers with discrepantly high IQ.

PubMed

Hancock, Roeland; Gabrieli, John D E; Hoeft, Fumiko

2016-12-01

It is currently believed that reading disability (RD) should be defined by reading level without regard to broader aptitude (IQ). There is debate, however, about how to classify individuals who read in the typical range but less well than would be expected by their higher IQ. We used functional magnetic resonance imaging (fMRI) in 49 children to examine whether those with typical, but discrepantly low reading ability relative to IQ, show dyslexia-like activation patterns during reading. Children who were typical readers with high-IQ discrepancy showed reduced activation in left temporoparietal neocortex relative to two control groups of typical readers without IQ discrepancy. This pattern was consistent and spatially overlapping with results in children with RD compared to typically reading children. The results suggest a shared neurological atypicality in regions associated with phonological processing between children with dyslexia and children with typical reading ability that is substantially below their IQ.

Dynamics of cell wall elasticity pattern shapes the cell during yeast mating morphogenesis

PubMed Central

Goldenbogen, Björn; Giese, Wolfgang; Hemmen, Marie; Uhlendorf, Jannis; Herrmann, Andreas

2016-01-01

The cell wall defines cell shape and maintains integrity of fungi and plants. When exposed to mating pheromone, Saccharomyces cerevisiae grows a mating projection and alters in morphology from spherical to shmoo form. Although structural and compositional alterations of the cell wall accompany shape transitions, their impact on cell wall elasticity is unknown. In a combined theoretical and experimental approach using finite-element modelling and atomic force microscopy (AFM), we investigated the influence of spatially and temporally varying material properties on mating morphogenesis. Time-resolved elasticity maps of shmooing yeast acquired with AFM in vivo revealed distinct patterns, with soft material at the emerging mating projection and stiff material at the tip. The observed cell wall softening in the protrusion region is necessary for the formation of the characteristic shmoo shape, and results in wider and longer mating projections. The approach is generally applicable to tip-growing fungi and plants cells. PMID:27605377

Stable Patterns of CENH3 Occupancy Through Maize Lineages Containing Genetically Similar Centromeres.

PubMed

Gent, Jonathan I; Wang, Kai; Jiang, Jiming; Dawe, R Kelly

2015-08-01

While the approximate chromosomal position of centromeres has been identified in many species, little is known about the dynamics and diversity of centromere positions within species. Multiple lines of evidence indicate that DNA sequence has little or no impact in specifying centromeres in maize and in most multicellular organisms. Given that epigenetically defined boundaries are expected to be dynamic, we hypothesized that centromere positions would change rapidly over time, which would result in a diversity of centromere positions in isolated populations. To test this hypothesis, we used CENP-A/cenH3 (CENH3 in maize) chromatin immunoprecipitation to define centromeres in breeding pedigrees that included the B73 inbred as a common parent. While we found a diversity of CENH3 profiles for centromeres with divergent sequences that were not inherited from B73, the CENH3 profiles from centromeres that were inherited from B73 were indistinguishable from each other. We propose that specific genetic elements in centromeric regions favor or inhibit CENH3 accumulation, leading to reproducible patterns of CENH3 occupancy. These data also indicate that dramatic shifts in centromere position normally originate from accumulated or large-scale genetic changes rather than from epigenetic positional drift. Copyright © 2015 by the Genetics Society of America.

Cholera epidemic in Haiti, 2010: using a transmission model to explain spatial spread of disease and identify optimal control interventions.

PubMed

Tuite, Ashleigh R; Tien, Joseph; Eisenberg, Marisa; Earn, David J D; Ma, Junling; Fisman, David N

2011-05-03

Haiti is in the midst of a cholera epidemic. Surveillance data for formulating models of the epidemic are limited, but such models can aid understanding of epidemic processes and help define control strategies. To predict, by using a mathematical model, the sequence and timing of regional cholera epidemics in Haiti and explore the potential effects of disease-control strategies. Compartmental mathematical model allowing person-to-person and waterborne transmission of cholera. Within- and between-region epidemic spread was modeled, with the latter dependent on population sizes and distance between regional centroids (a "gravity" model). Haiti, 2010 to 2011. Haitian hospitalization data, 2009 census data, literature-derived parameter values, and model calibration. Dates of epidemic onset and hospitalizations. The plausible range for cholera's basic reproductive number (R(0), defined as the number of secondary cases per primary case in a susceptible population without intervention) was 2.06 to 2.78. The order and timing of regional cholera outbreaks predicted by the gravity model were closely correlated with empirical observations. Analysis of changes in disease dynamics over time suggests that public health interventions have substantially affected this epidemic. A limited vaccine supply provided late in the epidemic was projected to have a modest effect. Assumptions were simplified, which was necessary for modeling. Projections are based on the initial dynamics of the epidemic, which may change. Despite limited surveillance data from the cholera epidemic in Haiti, a model simulating between-region disease transmission according to population and distance closely reproduces reported disease patterns. This model is a tool that planners, policymakers, and medical personnel seeking to manage the epidemic could use immediately.

Radiological features of primitive neuroectodermal tumors in intra-abdominal and retroperitoneal regions: A series of 18 cases

PubMed Central

Zhang, Youming; Xiao, Desheng; Yin, Hongling; Long, Xueying; Li, Li; Zai, Hongyan; Chen, Minfeng; Li, Wenzheng; Sun, Lunquan

2017-01-01

Objectives To characterize the imaging and clinicopathological features of primitive neuroectodermal tumors (PNETs) arising in intra-abdominal and retroperitoneal regions. Methods Eighteen patients with histopathologically proven intra-abdominal and retroperitoneal PNET were enrolled; computed tomography was performed for all cases, and magnetic resonance imaging was performed for a single case. Typical computed tomography and magnetic resonance imaging findings, including morphology, texture and enhancement features, as well as clinicopathological characteristics and prognosis data were retrospectively analyzed. Results Of eighteen PNET patients, fifteen were male and three were female, with a median age of 36 years (range, 2–65 years). The onset of symptoms was most often nonspecific and insidious. The mean tumor diameter was 7.2 cm (range, 3.0–12.1 cm), with necrosis in fifteen cases, cystic changes in eight, partition structure in five, calcification in five, hemorrhage in two, and mural nodules in one. Contrast enhanced computed tomography showed multiple tiny feeding arteries within the masses in six cases, resulting in a crab-like appearance, and mild ring enhancement pattern in five cases. Eleven cases showed surrounding invasion and metastasis. Of the eighteen PNET cases, nine cases showed smooth, well-defined margins, and nine cases had irregular, ill-defined margins. A median survival was 10.0±1.6 months. However, chemotherapy had efficacy on patients even those with advanced disease. Conclusions Primary intra-abdominal and retroperitoneal PNETs are rare, and imaging features documented here may help the diagnosis of this severe disease. Notably, two signs present in retroperitoneal PNET tumors, including a mild ring enhancement pattern and a crab-like appearance of the tiny feeding arteries, may have the potential to help us improve the ability to make a relatively reliable diagnosis. PMID:28319177

Draw your assay: Fabrication of low-cost paper-based diagnostic and multi-well test zones by drawing on a paper.

PubMed

Oyola-Reynoso, Stephanie; Heim, Andrew P; Halbertsma-Black, Julian; Zhao, C; Tevis, Ian D; Çınar, Simge; Cademartiri, Rebecca; Liu, Xinyu; Bloch, Jean-Francis; Thuo, Martin M

2015-11-01

Interest in low-cost diagnostic devices has recently gained attention, in part due to the rising cost of healthcare and the need to serve populations in resource-limited settings. A major challenge in the development of such devices is the need for hydrophobic barriers to contain polar bio-fluid analytes. Key approaches in lowering the cost in diagnostics have centered on (i) development of low-cost fabrication techniques/processes, (ii) use of affordable materials, or, (iii) minimizing the need for high-tech tools. This communication describes a simple, low-cost, adaptable, and portable method for patterning paper and subsequent use of the patterned paper in diagnostic tests. Our approach generates hydrophobic regions using a ball-point pen filled with a hydrophobizing molecule suspended in a solvent carrier. An empty ball-point pen was filled with a solution of trichloro perfluoroalkyl silane in hexanes (or hexadecane), and the pen used to draw lines on Whatman® chromatography 1 paper. The drawn regions defined the test zones since the trichloro silane reacts with the paper to give a hydrophobic barrier. The formation of the hydrophobic barriers is reaction kinetic and diffusion-limited, ensuring well defined narrow barriers. We performed colorimetric glucose assays and enzyme-linked immuno-sorbent assay (ELISA) using the created test zones. To demonstrate the versatility of this approach, we fabricated multiple devices on a single piece of paper and demonstrated the reproducibility of assays on these devices. The overall cost of devices fabricated by drawing are relatively lower (

The silence of the layers: Archaeological site visibility in the Pleistocene-Holocene transition at the Ebro Basin

NASA Astrophysics Data System (ADS)

Alday, Alfonso; Domingo, Rafael; Sebastián, María; Soto, Adriana; Aranbarri, Josu; González-Sampériz, Penélope; Sampietro-Vattuone, María Marta; Utrilla, Pilar; Montes, Lourdes; Peña-Monné, José Luis

2018-03-01

The Ebro Basin constitutes one of the most representative territories in SW Europe for the study of prehistoric societies during the Pleistocene-Holocene transition. The correlation of palaeoenvironmental and geomorphological proxies obtained from sedimentary records with chronologically well-constrained reference archaeological sites has allowed defining this time frame precisely, such that three main pilot areas haven been broadly depicted: the Alavese region, the Pre-Pyrenees and the Bajo Aragón. Overall, the human imprint in the Ebro Basin was rare during the Upper Palaeolithic, but more visible from the Upper Magdalenian (14500-13500 cal BP) to Neolithic times (up to 5500 cal BP). Local environmental resources were continuously managed by the prehistoric communities in the different areas of study. In fact, the Ebro Basin acted during those millennia as a whole, developing the same cultural trends, industrial techniques and settlement patterns in parallel throughout the territory. However, some gaps exist in the 14C frequency curve (SCDPD curve). This is partially related to prehistoric sites in particular lithologies and geological structures that could have partly been lost by erosional processes, especially during the Early Holocene. In addition, this gap also parallels the reconstructed climate trend for the Pre-Pyrenean and the Bajo Aragón areas, which are defined by high frequencies of xerophilous flora until ca. 9500 cal BP, suggesting that continental climate features could have hampered the presence of well-established human communities in inland regions. The interdisciplinary research (archaeology, geomorphology and palaeoclimatology) discussed in this paper offers clues to understand the existence of fills and gaps in the archaeological record of the Ebro Basin, and can be applied in other territories with similar geographic and climate patterns.

Identifying Clinical Factors Which Predict for Early Failure Patterns Following Resection for Pancreatic Adenocarcinoma in Patients Who Received Adjuvant Chemotherapy Without Chemoradiation.

PubMed

Walston, Steve; Salloum, Joseph; Grieco, Carmine; Wuthrick, Evan; Diaz, Dayssy A; Barney, Christian; Manilchuk, Andrei; Schmidt, Carl; Dillhoff, Mary; Pawlik, Timothy M; Williams, Terence M

2018-05-04

The role of radiation therapy (RT) in resected pancreatic cancer (PC) remains incompletely defined. We sought to determine clinical variables which predict for local-regional recurrence (LRR) to help select patients for adjuvant RT. We identified 73 patients with PC who underwent resection and adjuvant gemcitabine-based chemotherapy alone. We performed detailed radiologic analysis of first patterns of failure. LRR was defined as recurrence of PC within standard postoperative radiation volumes. Univariate analyses (UVA) were conducted using the Kaplan-Meier method and multivariate analyses (MVA) utilized the Cox proportional hazard ratio model. Factors significant on UVA were used for MVA. At median follow-up of 20 months, rates of local-regional recurrence only (LRRO) were 24.7%, LRR as a component of any failure 68.5%, metastatic recurrence (MR) as a component of any failure 65.8%, and overall disease recurrence (OR) 90.5%. On UVA, elevated postoperative CA 19-9 (>90 U/mL), pathologic lymph node positive (pLN+) disease, and higher tumor grade were associated with increased LRR, MR, and OR. On MVA, elevated postoperative CA 19-9 and pLN+ were associated with increased MR and OR. In addition, positive resection margin was associated with increased LRRO on both UVA and MVA. About 25% of patients with PC treated without adjuvant RT develop LRRO as initial failure. The only independent predictor of LRRO was positive margin, while elevated postoperative CA 19-9 and pLN+ were associated with predicting MR and overall survival. These data may help determine which patients benefit from intensification of local therapy with radiation.

Coordination and establishment of centralized facilities and services for the University of Alaska ERTS survey of the Alaskan environment

NASA Technical Reports Server (NTRS)

Belon, A. E. (Principal Investigator); Miller, J. M.

1973-01-01

The author has identified the following significant results. Scene 1072-21173 of the Anaktuvuk Pass region of the Brooks Range, Alaska, was studied from the point of view of a resource survey for purposes of land use planning as part of the effort to develop ERTS data processing and interpretation techniques. Other data sources and surface observations were utilized to produce a resource survey of a remote and undeveloped region of Alaska. Three vegetative types are apparent: moist tundra, low brush, and high brush. Watersheds are easily defined on the multispectral imagery. Features related indirectly to economic minerals are discernible from ERTS-1 imagery supported by ground truth data. These include mountains, outwash plains and alluvial deposits, drainage patterns, lineaments and probable bedding planes. This region falls within present land class categories which are not inconsistent with the imperatives of the resources. These land class categories include native village withdrawals, regional deficiency area, national interest study area for possible inclusion in a national system, public interest areas, utility corridor, and state land selection.

Electric field measurements across the harang discontinuity. [of the auroral zone

NASA Technical Reports Server (NTRS)

Maynard, N. C.

1974-01-01

The Harang discontinuity, the area separating the positive and negative bay regions in the midnight sector of the auroral zone, is a focal point for changes in behavior of many phenomena. Through this region the electric field rotates through the west from a basically northward field in the positive bay region to a basically southward field in the negative bay region, appearing as a reversal in a single axis measurement; 32 of these reversals have been identified in the OGO-6 data from November and December, 1969. The discontinuity is dynamic in nature, moving southward and steepening its latitudinal profile as magnetic activity is increased. As activity decreases it relaxes poleward and spreads out in latitudinal width. It occurs over several hours of magnetic local time. The boundary in the electric field data is consistent with the reversal of ground magnetic disturbances from a positive to negative bay condition. The discontinuity is present in the electric field data both during substorms and during quiet times and appears to define a pattern on which other effects can occur.

Patterns of authorship on community health workers in low-and-middle-income countries: an analysis of publications (2012–2016)

PubMed Central

Maleka, Nelisiwe

2018-01-01

Introduction Studies of authorship provide a barometer of local research capacity and ownership of research, considered key to defining appropriate research priorities, developing contextualised responses to health problems and ensuring that research informs policy and practice. This paper reports on an analysis of patterns of research authorship of the now substantial literature on community health workers (CHWs) in low-and-middle-income countries (LMICs) for the 5-year period: 2012–2016. Methods A search of five databases identified a total of 649 indexed publications reporting on CHWs in LMICs and meeting the inclusion criteria. The country, region and income classification of studies, affiliations (country, organisation) of lead (first) and last authors, proportions of all authors locally affiliated, programme area (eg, maternal child health) and funding source were extracted. Results The 649 papers reported experiences from 51 countries, 55% from middle-income countries (MICs) and 32% from low-income countries (LICs), with the remaining 13% multicountry studies. Overall, 47% and 54% of all the papers had a high-income country (HIC) lead and last author, respectively. Authorship followed three patterns: (1) a concentrated HIC pattern, with US-based authors numerically dominating LIC-based and multicountry studies; (2) an MIC pattern of autonomy, with a handful of countries—India, South Africa and Brazil, in particular—leading >70% of their CHW publications and (3) a pattern of unevenness among LICs in their lead authorship of publications varying from 14% (Malawi) to 54% (Uganda). Region, programme area and funding source were all associated with the distribution of authorship across country income categories. Conclusion The findings in this analysis mirror closely that of other authorship studies in global health. Collectively these provide a common message—that investments in global health programmes in the Millennium Development Goal era may have benefited health but not necessarily capacity for knowledge generation in LMICs. PMID:29765777

An Innovative Metric to Evaluate Satellite Precipitation's Spatial Distribution

NASA Astrophysics Data System (ADS)

Liu, H.; Chu, W.; Gao, X.; Sorooshian, S.

2011-12-01

Thanks to its capability to cover the mountains, where ground measurement instruments cannot reach, satellites provide a good means of estimating precipitation over mountainous regions. In regions with complex terrains, accurate information on high-resolution spatial distribution of precipitation is critical for many important issues, such as flood/landslide warning, reservoir operation, water system planning, etc. Therefore, in order to be useful in many practical applications, satellite precipitation products should possess high quality in characterizing spatial distribution. However, most existing validation metrics, which are based on point/grid comparison using simple statistics, cannot effectively measure satellite's skill of capturing the spatial patterns of precipitation fields. This deficiency results from the fact that point/grid-wised comparison does not take into account of the spatial coherence of precipitation fields. Furth more, another weakness of many metrics is that they can barely provide information on why satellite products perform well or poor. Motivated by our recent findings of the consistent spatial patterns of the precipitation field over the western U.S., we developed a new metric utilizing EOF analysis and Shannon entropy. The metric can be derived through two steps: 1) capture the dominant spatial patterns of precipitation fields from both satellite products and reference data through EOF analysis, and 2) compute the similarities between the corresponding dominant patterns using mutual information measurement defined with Shannon entropy. Instead of individual point/grid, the new metric treat the entire precipitation field simultaneously, naturally taking advantage of spatial dependence. Since the dominant spatial patterns are shaped by physical processes, the new metric can shed light on why satellite product can or cannot capture the spatial patterns. For demonstration, a experiment was carried out to evaluate a satellite precipitation product, CMORPH, against the U.S. daily precipitation analysis of Climate Prediction Center (CPC) at a daily and .25o scale over the Western U.S.

Patterns of authorship on community health workers in low-and-middle-income countries: an analysis of publications (2012-2016).

PubMed

Schneider, Helen; Maleka, Nelisiwe

2018-01-01

Studies of authorship provide a barometer of local research capacity and ownership of research, considered key to defining appropriate research priorities, developing contextualised responses to health problems and ensuring that research informs policy and practice. This paper reports on an analysis of patterns of research authorship of the now substantial literature on community health workers (CHWs) in low-and-middle-income countries (LMICs) for the 5-year period: 2012-2016. A search of five databases identified a total of 649 indexed publications reporting on CHWs in LMICs and meeting the inclusion criteria. The country, region and income classification of studies, affiliations (country, organisation) of lead (first) and last authors, proportions of all authors locally affiliated, programme area (eg, maternal child health) and funding source were extracted. The 649 papers reported experiences from 51 countries, 55% from middle-income countries (MICs) and 32% from low-income countries (LICs), with the remaining 13% multicountry studies. Overall, 47% and 54% of all the papers had a high-income country (HIC) lead and last author, respectively. Authorship followed three patterns: (1) a concentrated HIC pattern, with US-based authors numerically dominating LIC-based and multicountry studies; (2) an MIC pattern of autonomy, with a handful of countries-India, South Africa and Brazil, in particular-leading >70% of their CHW publications and (3) a pattern of unevenness among LICs in their lead authorship of publications varying from 14% (Malawi) to 54% (Uganda). Region, programme area and funding source were all associated with the distribution of authorship across country income categories. The findings in this analysis mirror closely that of other authorship studies in global health. Collectively these provide a common message-that investments in global health programmes in the Millennium Development Goal era may have benefited health but not necessarily capacity for knowledge generation in LMICs.

Evaluation of a functional epigenetic approach to identify promoter region methylation in phaeochromocytoma and neuroblastoma

PubMed Central

Margetts, Caroline D E; Morris, Mark; Astuti, Dewi; Gentle, Dean C; Cascon, Alberto; McRonald, Fiona E; Catchpoole, Daniel; Robledo, Mercedes; Neumann, Hartmut P H; Latif, Farida; Maher, Eamonn R

2008-01-01

The molecular genetics of inherited phaeochromocytoma have received considerable attention, but the somatic genetic and epigenetic events that characterise tumourigenesis in sporadic phaeochromocytomas are less well defined. Previously, we found considerable overlap between patterns of promoter region tumour suppressor gene (TSG) hypermethylation in two neural crest tumours, neuroblastoma and phaeochromocytoma. In order to identify candidate biomarkers and epigenetically inactivated TSGs in phaeochromocytoma and neuroblastoma, we characterised changes in gene expression in three neuroblastoma cell lines after treatment with the demethylating agent 5-azacytidine. Promoter region methylation status was then determined for 28 genes that demonstrated increased expression after demethylation. Three genes HSP47, homeobox A9 (HOXA9) and opioid binding protein (OPCML) were methylated in >10% of phaeochromocytomas (52, 17 and 12% respectively). Two of the genes, epithelial membrane protein 3 (EMP3) and HSP47, demonstrated significantly more frequent methylation in neuroblastoma than phaeochromocytoma. These findings extend epigenotype of phaeochromocytoma and identify candidate genes implicated in sporadic phaeochromocytoma tumourigenesis. PMID:18499731

Nonuniform ocean acidification and attenuation of the ocean carbon sink

NASA Astrophysics Data System (ADS)

Fassbender, Andrea J.; Sabine, Christopher L.; Palevsky, Hilary I.

2017-08-01

Surface ocean carbon chemistry is changing rapidly. Partial pressures of carbon dioxide gas (pCO2) are rising, pH levels are declining, and the ocean's buffer capacity is eroding. Regional differences in short-term pH trends primarily have been attributed to physical and biological processes; however, heterogeneous seawater carbonate chemistry may also be playing an important role. Here we use Surface Ocean CO2 Atlas Version 4 data to develop 12 month gridded climatologies of carbonate system variables and explore the coherent spatial patterns of ocean acidification and attenuation in the ocean carbon sink caused by rising atmospheric pCO2. High-latitude regions exhibit the highest pH and buffer capacity sensitivities to pCO2 increases, while the equatorial Pacific is uniquely insensitive due to a newly defined aqueous CO2 concentration effect. Importantly, dissimilar regional pH trends do not necessarily equate to dissimilar acidity ([H+]) trends, indicating that [H+] is a more useful metric of acidification.

Spontaneous cortical activity alternates between motifs defined by regional axonal projections

PubMed Central

Mohajerani, Majid H.; Chan, Allen W.; Mohsenvand, Mostafa; LeDue, Jeffrey; Liu, Rui; McVea, David A.; Boyd, Jamie D.; Wang, Yu Tian; Reimers, Mark; Murphy, Timothy H.

2014-01-01

In lightly anaesthetized or awake adult mice using millisecond timescale voltage sensitive dye imaging, we show that a palette of sensory-evoked and hemisphere-wide activity motifs are represented in spontaneous activity. These motifs can reflect multiple modes of sensory processing including vision, audition, and touch. Similar cortical networks were found with direct cortical activation using channelrhodopsin-2. Regional analysis of activity spread indicated modality specific sources such as primary sensory areas, and a common posterior-medial cortical sink where sensory activity was extinguished within the parietal association area, and a secondary anterior medial sink within the cingulate/secondary motor cortices for visual stimuli. Correlation analysis between functional circuits and intracortical axonal projections indicated a common framework corresponding to long-range mono-synaptic connections between cortical regions. Maps of intracortical mono-synaptic structural connections predicted hemisphere-wide patterns of spontaneous and sensory-evoked depolarization. We suggest that an intracortical monosynaptic connectome shapes the ebb and flow of spontaneous cortical activity. PMID:23974708

Has the magnitude of floods across the USA changed with global CO2 levels?

USGS Publications Warehouse

Hirsch, Robert M.; Ryberg, Karen R.

2012-01-01

Statistical relationships between annual floods at 200 long-term (85–127 years of record) streamgauges in the coterminous United States and the global mean carbon dioxide concentration (GMCO2) record are explored. The streamgauge locations are limited to those with little or no regulation or urban development. The coterminous US is divided into four large regions and stationary bootstrapping is used to evaluate if the patterns of these statistical associations are significantly different from what would be expected under the null hypothesis that flood magnitudes are independent of GMCO2. In none of the four regions defined in this study is there strong statistical evidence for flood magnitudes increasing with increasing GMCO2. One region, the southwest, showed a statistically significant negative relationship between GMCO2 and flood magnitudes. The statistical methods applied compensate both for the inter-site correlation of flood magnitudes and the shorter-term (up to a few decades) serial correlation of floods.

Has the magnitude of floods across the USA changed with global CO 2 levels?

USGS Publications Warehouse

Hirsch, R.M.; Ryberg, K.R.

2012-01-01

Statistical relationships between annual floods at 200 long-term (85-127 years of record) streamgauges in the coterminous United States and the global mean carbon dioxide concentration (GMCO2) record are explored. The streamgauge locations are limited to those with little or no regulation or urban development. The coterminous US is divided into four large regions and stationary bootstrapping is used to evaluate if the patterns of these statistical associations are significantly different from what would be expected under the null hypothesis that flood magnitudes are independent of GMCO2. In none of the four regions defined in this study is there strong statistical evidence for flood magnitudes increasing with increasing GMCO2. One region, the southwest, showed a statistically significant negative relationship between GMCO2 and flood magnitudes. The statistical methods applied compensate both for the inter-site correlation of flood magnitudes and the shorter-term (up to a few decades) serial correlation of floods.

An architecture for encoding sentence meaning in left mid-superior temporal cortex

PubMed Central

Frankland, Steven M.; Greene, Joshua D.

2015-01-01

Human brains flexibly combine the meanings of words to compose structured thoughts. For example, by combining the meanings of “bite,” “dog,” and “man,” we can think about a dog biting a man, or a man biting a dog. Here, in two functional magnetic resonance imaging (fMRI) experiments using multivoxel pattern analysis (MVPA), we identify a region of left mid-superior temporal cortex (lmSTC) that flexibly encodes “who did what to whom” in visually presented sentences. We find that lmSTC represents the current values of abstract semantic variables (“Who did it?” and “To whom was it done?”) in distinct subregions. Experiment 1 first identifies a broad region of lmSTC whose activity patterns (i) facilitate decoding of structure-dependent sentence meaning (“Who did what to whom?”) and (ii) predict affect-related amygdala responses that depend on this information (e.g., “the baby kicked the grandfather” vs. “the grandfather kicked the baby”). Experiment 2 then identifies distinct, but neighboring, subregions of lmSTC whose activity patterns carry information about the identity of the current “agent” (“Who did it?”) and the current “patient” (“To whom was it done?”). These neighboring subregions lie along the upper bank of the superior temporal sulcus and the lateral bank of the superior temporal gyrus, respectively. At a high level, these regions may function like topographically defined data registers, encoding the fluctuating values of abstract semantic variables. This functional architecture, which in key respects resembles that of a classical computer, may play a critical role in enabling humans to flexibly generate complex thoughts. PMID:26305927

Histone methylation at gene promoters is associated with developmental regulation and region-specific expression of ionotropic and metabotropic glutamate receptors in human brain.

PubMed

Stadler, Florian; Kolb, Gabriele; Rubusch, Lothar; Baker, Stephen P; Jones, Edward G; Akbarian, Schahram

2005-07-01

Glutamatergic signaling is regulated, in part, through differential expression of NMDA and AMPA/KA channel subunits and G protein-coupled metabotropic receptors. In human brain, region-specific expression patterns of glutamate receptor genes are maintained over the course of decades, suggesting a role for molecular mechanisms involved in long-term regulation of transcription, including methylation of lysine residues at histone N-terminal tails. Using a native chromatin immunoprecipitation assay, we studied histone methylation marks at proximal promoters of 16 ionotropic and metabotropic glutamate receptor genes (GRIN1,2A-D; GRIA1,3,4; GRIK2,4,5; GRM1,3,4,6,7 ) in cerebellar cortex collected across a wide age range from midgestation to 90 years old. Levels of di- and trimethylated histone H3-lysine 4, which are associated with open chromatin and transcription, showed significant differences between promoters and a robust correlation with corresponding mRNA levels in immature and mature cerebellar cortex. In contrast, levels of trimethylated H3-lysine 27 and H4-lysine 20, two histone modifications defining silenced or condensed chromatin, did not correlate with transcription but were up-regulated overall in adult cerebellum. Furthermore, differential gene expression patterns in prefrontal and cerebellar cortex were reflected by similar differences in H3-lysine 4 methylation at promoters. Together, these findings suggest that histone lysine methylation at gene promoters is involved in developmental regulation and maintenance of region-specific expression patterns of ionotropic and metabotropic glutamate receptors. The association of a specific epigenetic mark, H3-(methyl)-lysine 4, with the molecular architecture of glutamatergic signaling in human brain has potential implications for schizophrenia and other disorders with altered glutamate receptor function.

A diagram for evaluating multiple aspects of model performance in simulating vector fields

NASA Astrophysics Data System (ADS)

Xu, Zhongfeng; Hou, Zhaolu; Han, Ying; Guo, Weidong

2016-12-01

Vector quantities, e.g., vector winds, play an extremely important role in climate systems. The energy and water exchanges between different regions are strongly dominated by wind, which in turn shapes the regional climate. Thus, how well climate models can simulate vector fields directly affects model performance in reproducing the nature of a regional climate. This paper devises a new diagram, termed the vector field evaluation (VFE) diagram, which is a generalized Taylor diagram and able to provide a concise evaluation of model performance in simulating vector fields. The diagram can measure how well two vector fields match each other in terms of three statistical variables, i.e., the vector similarity coefficient, root mean square length (RMSL), and root mean square vector difference (RMSVD). Similar to the Taylor diagram, the VFE diagram is especially useful for evaluating climate models. The pattern similarity of two vector fields is measured by a vector similarity coefficient (VSC) that is defined by the arithmetic mean of the inner product of normalized vector pairs. Examples are provided, showing that VSC can identify how close one vector field resembles another. Note that VSC can only describe the pattern similarity, and it does not reflect the systematic difference in the mean vector length between two vector fields. To measure the vector length, RMSL is included in the diagram. The third variable, RMSVD, is used to identify the magnitude of the overall difference between two vector fields. Examples show that the VFE diagram can clearly illustrate the extent to which the overall RMSVD is attributed to the systematic difference in RMSL and how much is due to the poor pattern similarity.

MODIS-based spatiotemporal patterns of soil moisture and evapotranspiration interactions in Tampa Bay urban watershed

NASA Astrophysics Data System (ADS)

Chang, Ni-Bin; Xuan, Zhemin; Wimberly, Brent

2011-09-01

Soil moisture and evapotranspiration (ET) is affected by both water and energy balances in the soilvegetation- atmosphere system, it involves many complex processes in the nexus of water and thermal cycles at the surface of the Earth. These impacts may affect the recharge of the upper Floridian aquifer. The advent of urban hydrology and remote sensing technologies opens new and innovative means to undertake eventbased assessment of ecohydrological effects in urban regions. For assessing these landfalls, the multispectral Moderate Resolution Imaging Spectroradiometer (MODIS) remote sensing images can be used for the estimation of such soil moisture change in connection with two other MODIS products - Enhanced Vegetation Index (EVI), Land Surface Temperature (LST). Supervised classification for soil moisture retrieval was performed for Tampa Bay area on the 2 kmx2km grid with MODIS images. Machine learning with genetic programming model for soil moisture estimation shows advances in image processing, feature extraction, and change detection of soil moisture. ET data that were derived by Geostationary Operational Environmental Satellite (GOES) data and hydrologic models can be retrieved from the USGS web site directly. Overall, the derived soil moisture in comparison with ET time series changes on a seasonal basis shows that spatial and temporal variations of soil moisture and ET that are confined within a defined region for each type of surfaces, showing clustered patterns and featuring space scatter plot in association with the land use and cover map. These concomitant soil moisture patterns and ET fluctuations vary among patches, plant species, and, especially, location on the urban gradient. Time series plots of LST in association with ET, soil moisture and EVI reveals unique ecohydrological trends. Such ecohydrological assessment can be applied for supporting the urban landscape management in hurricane-stricken regions.

The consequences of land-cover changes on soil erosion distribution in Slovakia

NASA Astrophysics Data System (ADS)

Cebecauer, Tomáš; Hofierka, Jaroslav

2008-06-01

Soil erosion is a complex process determined by mutual interaction of numerous factors. The aim of erosion research at regional scales is a general evaluation of the landscape susceptibility to soil erosion by water, taking into account the main factors influencing this process. One of the key factors influencing the susceptibility of a region to soil erosion is land cover. Natural as well as human-induced changes of landscape may result in both the diminishment and acceleration of soil erosion. Recent studies of land-cover changes indicate that during the last decade more than 4.11% of Slovak territory has changed. The objective of this study is to assess the influence of land-cover and crop rotation changes over the 1990-2000 period on the intensity and spatial pattern of soil erosion in Slovakia. The assessment is based on principles defined in the Universal Soil Loss Equation (USLE) modified for application at regional scale and the use of the CORINE land cover (CLC) databases for 1990 and 2000. The C factor for arable land has been refined using statistical data on the mean crop rotation and the acreage of particular agricultural crops in the districts of Slovakia. The L factor has been calculated using sample areas with parcels identified by LANDSAT TM data. The results indicate that the land-cover and crop rotation changes had a significant influence on soil erosion pattern predominately in the hilly and mountainous parts of Slovakia. The pattern of soil erosion changes exhibits high spatial variation with overall slightly decreased soil erosion risks. These changes are associated with ongoing land ownership changes, changing structure of crops, deforestation and afforestation.

Bipolar plate/diffuser for a proton exchange membrane fuel cell

DOEpatents

Besmann, Theodore M.; Burchell, Timothy D.

2001-01-01

A combination bipolar plate/diffuser fuel cell component includes an electrically conducting solid material having: a porous region having a porous surface; and a hermetic region, the hermetic region defining at least a portion of at least one coolant channel, the porous region defining at least a portion of at least one reactant channel, the porous region defining a flow field medium for diffusing the reactant to the porous surface.

Bipolar plate/diffuser for a proton exchange membrane fuel cell

DOEpatents

Besmann, Theodore M.; Burchell, Timothy D.

2000-01-01

A combination bipolar plate/diffuser fuel cell component includes an electrically conducting solid material having: a porous region having a porous surface; and a hermetic region, the hermetic region defining at least a portion of at least one coolant channel, the porous region defining at least a portion of at least one reactant channel, the porous region defining a flow field medium for diffusing the reactant to the porous surface.

Finding Spatio-Temporal Patterns in Large Sensor Datasets

ERIC Educational Resources Information Center

McGuire, Michael Patrick

2010-01-01

Spatial or temporal data mining tasks are performed in the context of the relevant space, defined by a spatial neighborhood, and the relevant time period, defined by a specific time interval. Furthermore, when mining large spatio-temporal datasets, interesting patterns typically emerge where the dataset is most dynamic. This dissertation is…

Spatial-Temporal Distribution of Hantavirus Rodent-Borne Infection by Oligoryzomys fulvescens in the Agua Buena Region - Panama

PubMed Central

Gonzalez, Publio; Cumbrera, Alberto; Rivero, Alina; Avila, Mario; Armién, Aníbal G.; Koster, Frederick; Glass, Gregory

2016-01-01

Background Hotspot detection and characterization has played an increasing role in understanding the maintenance and transmission of zoonotic pathogens. Identifying the specific environmental factors (or their correlates) that influence reservoir host abundance help increase understanding of how pathogens are maintained in natural systems and are crucial to identifying disease risk. However, most recent studies are performed at macro-scale and describe broad temporal patterns of population abundances. Few have been conducted at a microscale over short time periods that better capture the dynamical patterns of key populations. These finer resolution studies may better define the likelihood of local pathogen persistence. This study characterizes the landscape distribution and spatio-temporal dynamics of Oligoryzomys fulvescens (O. fulvescens), an important mammalian reservoir in Central America. Methods Information collected in a longitudinal study of rodent populations in the community of Agua Buena in Tonosí, Panama, between April 2006 and December 2009 was analyzed using non-spatial analyses (box plots) and explicit spatial statistical tests (correlograms, SADIE and LISA). A 90 node grid was built (raster format) to design a base map. The area between the nodes was 0.09 km2 and the total study area was 6.43 km2 (2.39 x 2.69 km). The temporal assessment dataset was divided into four periods for each year studied: the dry season, rainy season, and two months-long transitions between seasons (the months of April and December). Results There were heterogeneous patterns in the population densities and degrees of dispersion of O. fulvescens that varied across seasons and among years. The species typically was locally absent during the late transitional months of the season, and re-established locally in subsequent years. These populations re-occurred in the same area during the first three years but subsequently re-established further south in the final year of the study. Spatial autocorrelation analyses indicated local populations encompassed approximately 300–600 m. The borders between suitable and unsuitable habitats were sharply demarcated over short distances. Conclusion Oligoryzomys fulvescens showed a well-defined spatial pattern that evolved over time, and led to a pattern of changing aggregation. Thus, hot spots of abundance showed a general shifting pattern that helps explain the intermittent risk from pathogens transmitted by this species. This variation was associated with seasonality, as well as anthropogenic pressures that occurred with agricultural activities. These factors help define the characteristics of the occurrence, timing, intensity and duration of synanthropic populations affected by human populations and, consequently, possible exposure that local human populations experience. PMID:26894436

Spatial-Temporal Distribution of Hantavirus Rodent-Borne Infection by Oligoryzomys fulvescens in the Agua Buena Region--Panama.

PubMed

Armién, Blas; Ortiz, Paulo Lazaro; Gonzalez, Publio; Cumbrera, Alberto; Rivero, Alina; Avila, Mario; Armién, Aníbal G; Koster, Frederick; Glass, Gregory

2016-02-01

Hotspot detection and characterization has played an increasing role in understanding the maintenance and transmission of zoonotic pathogens. Identifying the specific environmental factors (or their correlates) that influence reservoir host abundance help increase understanding of how pathogens are maintained in natural systems and are crucial to identifying disease risk. However, most recent studies are performed at macro-scale and describe broad temporal patterns of population abundances. Few have been conducted at a microscale over short time periods that better capture the dynamical patterns of key populations. These finer resolution studies may better define the likelihood of local pathogen persistence. This study characterizes the landscape distribution and spatio-temporal dynamics of Oligoryzomys fulvescens (O. fulvescens), an important mammalian reservoir in Central America. Information collected in a longitudinal study of rodent populations in the community of Agua Buena in Tonosí, Panama, between April 2006 and December 2009 was analyzed using non-spatial analyses (box plots) and explicit spatial statistical tests (correlograms, SADIE and LISA). A 90 node grid was built (raster format) to design a base map. The area between the nodes was 0.09 km(2) and the total study area was 6.43 km(2) (2.39 x 2.69 km). The temporal assessment dataset was divided into four periods for each year studied: the dry season, rainy season, and two months-long transitions between seasons (the months of April and December). There were heterogeneous patterns in the population densities and degrees of dispersion of O. fulvescens that varied across seasons and among years. The species typically was locally absent during the late transitional months of the season, and re-established locally in subsequent years. These populations re-occurred in the same area during the first three years but subsequently re-established further south in the final year of the study. Spatial autocorrelation analyses indicated local populations encompassed approximately 300-600 m. The borders between suitable and unsuitable habitats were sharply demarcated over short distances. Oligoryzomys fulvescens showed a well-defined spatial pattern that evolved over time, and led to a pattern of changing aggregation. Thus, hot spots of abundance showed a general shifting pattern that helps explain the intermittent risk from pathogens transmitted by this species. This variation was associated with seasonality, as well as anthropogenic pressures that occurred with agricultural activities. These factors help define the characteristics of the occurrence, timing, intensity and duration of synanthropic populations affected by human populations and, consequently, possible exposure that local human populations experience.

Advanced brain aging: relationship with epidemiologic and genetic risk factors, and overlap with Alzheimer disease atrophy patterns.

PubMed

Habes, M; Janowitz, D; Erus, G; Toledo, J B; Resnick, S M; Doshi, J; Van der Auwera, S; Wittfeld, K; Hegenscheid, K; Hosten, N; Biffar, R; Homuth, G; Völzke, H; Grabe, H J; Hoffmann, W; Davatzikos, C

2016-04-05

We systematically compared structural imaging patterns of advanced brain aging (ABA) in the general-population, herein defined as significant deviation from typical BA to those found in Alzheimer disease (AD). The hypothesis that ABA would show different patterns of structural change compared with those found in AD was tested via advanced pattern analysis methods. In particular, magnetic resonance images of 2705 participants from the Study of Health in Pomerania (aged 20-90 years) were analyzed using an index that captures aging atrophy patterns (Spatial Pattern of Atrophy for Recognition of BA (SPARE-BA)), and an index previously shown to capture atrophy patterns found in clinical AD (Spatial Patterns of Abnormality for Recognition of Early Alzheimer's Disease (SPARE-AD)). We studied the association between these indices and risk factors, including an AD polygenic risk score. Finally, we compared the ABA-associated atrophy with typical AD-like patterns. We observed that SPARE-BA had significant association with: smoking (P<0.05), anti-hypertensive (P<0.05), anti-diabetic drug use (men P<0.05, women P=0.06) and waist circumference for the male cohort (P<0.05), after adjusting for age. Subjects with ABA had spatially extensive gray matter loss in the frontal, parietal and temporal lobes (false-discovery-rate-corrected q<0.001). ABA patterns of atrophy were partially overlapping with, but notably deviating from those typically found in AD. Subjects with ABA had higher SPARE-AD values; largely due to the partial spatial overlap of associated patterns in temporal regions. The AD polygenic risk score was significantly associated with SPARE-AD but not with SPARE-BA. Our findings suggest that ABA is likely characterized by pathophysiologic mechanisms that are distinct from, or only partially overlapping with those of AD.

Temporal and spatial patterns of wetland extent influence variability of surface water connectivity in the Prairie Pothole Region, United States

USGS Publications Warehouse

Vanderhoof, Melanie; Alexander, Laurie C.; Todd, Jason

2016-01-01

Context. Quantifying variability in landscape-scale surface water connectivity can help improve our understanding of the multiple effects of wetlands on downstream waterways. Objectives. We examined how wetland merging and the coalescence of wetlands with streams varied both spatially (among ecoregions) and interannually (from drought to deluge) across parts of the Prairie Pothole Region. Methods. Wetland extent was derived over a time series (1990-2011) using Landsat imagery. Changes in landscape-scale connectivity, generated by the physical coalescence of wetlands with other surface water features, were quantified by fusing static wetland and stream datasets with Landsat-derived wetland extent maps, and related to multiple wetness indices. The usage of Landsat allows for decadal-scale analysis, but limits the types of surface water connections that can be detected. Results. Wetland extent correlated positively with the merging of wetlands and wetlands with streams. Wetness conditions, as defined by drought indices and runoff, were positively correlated with wetland extent, but less consistently correlated with measures of surface water connectivity. The degree of wetland-wetland merging was found to depend less on total wetland area or density, and more on climate conditions, as well as the threshold for how wetland/upland was defined. In contrast, the merging of wetlands with streams was positively correlated with stream density, and inversely related to wetland density. Conclusions. Characterizing the degree of surface water connectivity within the Prairie Pothole Region in North America requires consideration of 1) climate-driven variation in wetness conditions and 2) within-region variation in wetland and stream spatial arrangements.

Level IV Ecoregions of the Conterminous United States

EPA Pesticide Factsheets

Ecoregions denote areas of general similarity in ecosystems and in the type, quality, and quantity of environmental resources. They are designed to serve as a spatial framework for the research, assessment, management, and monitoring of ecosystems and ecosystem components. These general purpose regions are critical for structuring and implementing ecosystem management strategies across federal agencies, state agencies, and nongovernment organizations that are responsible for different types of resources within the same geographical areas. The approach used to compile this map is based on the premise that ecological regions can be identified through the analysis of patterns of biotic and abiotic phenomena, including geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology. The relative importance of each characteristic varies from one ecological region to another. A Roman numeral hierarchical scheme has been adopted for different levels for ecological regions. Level I is the coarsest level, dividing North America into 15 ecological regions. Level II divides the continent into 50 regions (Commission for Environmental Cooperation Working Group, 1997). At Level III, the continental United States contains 105 regions whereas the conterminous United States has 85 (U.S. Environmental Protection Agency, 2005). Level IV ecoregions are further subdivisions of Level III ecoregions. Methods used to define the ecoregions are explained in Omernik (

Deciphering RNA-Recognition Patterns of Intrinsically Disordered Proteins.

PubMed

Srivastava, Ambuj; Ahmad, Shandar; Gromiha, M Michael

2018-05-29

Intrinsically disordered regions (IDRs) and protein (IDPs) are highly flexible owing to their lack of well-defined structures. A subset of such proteins interacts with various substrates; including RNA; frequently adopting regular structures in the final complex. In this work; we have analysed a dataset of protein⁻RNA complexes undergoing disorder-to-order transition (DOT) upon binding. We found that DOT regions are generally small in size (less than 3 residues) for RNA binding proteins. Like structured proteins; positively charged residues are found to interact with RNA molecules; indicating the dominance of electrostatic and cation-π interactions. However, a comparison of binding frequency shows that interface hydrophobic and aromatic residues have more interactions in only DOT regions than in a protein. Further; DOT regions have significantly higher exposure to water than their structured counterparts. Interactions of DOT regions with RNA increase the sheet formation with minor changes in helix forming residues. We have computed the interaction energy for amino acids⁻nucleotide pairs; which showed the preference of His⁻G; Asn⁻U and Ser⁻U at for the interface of DOT regions. This study provides insights to understand protein⁻RNA interactions and the results could also be used for developing a tool for identifying DOT regions in RNA binding proteins.

Using rare earth elements for the identification of the geographic origin of food

NASA Astrophysics Data System (ADS)

Meisel, T.; Bandoniene, D.; Joebstl, D.

2009-04-01

The European Union defined regimes within the Protected Geographical Status (PGS) framework to protect names of regional food specialities. Thus only food produced in a specific geographical area with a specific way of production or quality can be protected by a protected geographical indication (PGI) label. As such Styrian Pumpkin Seed Oil has been approved with this label, but as with many other high priced regional specialities, fraud cannot be excluded or nor identified. Thus the aim of this work is, to develop an analytical method for the control of the geographic origin of pumpkin seed oil and also to test the method for other protected products. The development of such a method is not only of interest for scientists, but also of importance for the consumer wanting to know the origin of the food products and the assurance of the purity and quality. The group of rare earth elements (REE) in plants also have a characteristic distribution pattern similar to upper crustal REE distributions. Since the REE concentrations are extremely low in pumpkin seed oil (ppt to low ppb), ICP-MS was the only sensitive tool able to produce validated results. The carrier of the REE are most likely small particles distributed within the pumpkin seed oil. Unlike, e.g., olive oil, pumpkin seed oil is bottled and sold unfiltered, which makes this Styrian speciality an interesting sampling target. As pumpkin seed oils from different geographic origin show variable trace element and rare earth distribution patterns, is should possible to trace the origin of these oils. In the current project pumpkin seeds from different regions in Austria and from abroad were sampled. The trace element patterns in the extracted oil of these seeds were determined and a preliminary classification with discriminate analysis was successfully done on a statistical basis. In addition to the study of the geographic origin it was demonstrated that REE distribution patterns can also be used for the identification of adulteration of high priced pumpkin seed oil with cheap neutral tasting refined oils. Interestingly enough, the variations of the REE patterns between oils from different regions are much more pronounced than their host soils. Thus we assume that microbiological processes in the rhizosphere are in control of the REE uptake into the plant. Regional variations of the microbiological composition of the soils and probably not only a priori the bulk soil composition of the minerals in the soil are the cause of the regional variations making it possible to identify the geographic origin of pumpkin seeds and as a consequence the pumpkin seed oil.

Finger crease pattern recognition using Legendre moments and principal component analysis

NASA Astrophysics Data System (ADS)

Luo, Rongfang; Lin, Tusheng

2007-03-01

The finger joint lines defined as finger creases and its distribution can identify a person. In this paper, we propose a new finger crease pattern recognition method based on Legendre moments and principal component analysis (PCA). After obtaining the region of interest (ROI) for each finger image in the pre-processing stage, Legendre moments under Radon transform are applied to construct a moment feature matrix from the ROI, which greatly decreases the dimensionality of ROI and can represent principal components of the finger creases quite well. Then, an approach to finger crease pattern recognition is designed based on Karhunen-Loeve (K-L) transform. The method applies PCA to a moment feature matrix rather than the original image matrix to achieve the feature vector. The proposed method has been tested on a database of 824 images from 103 individuals using the nearest neighbor classifier. The accuracy up to 98.584% has been obtained when using 4 samples per class for training. The experimental results demonstrate that our proposed approach is feasible and effective in biometrics.

Diuretic renography in evaluating dilated upper urinary tract in children

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ireton, R.C.; Parker, R.M.; Hayden, P.

1987-02-01

The diuretic renogram provides a previously unavailable noninvasive method for assessing and following urinary tract dilation of diverse cause, and defining true obstruction in children. Technetium-99m-DTPA (diethylenetriaminepentaacetic acid) is injected intravenously and a posteriorly placed gamma scintillation camera used to image the kidneys, ureters, and bladder. Furosemide is subsequently injected to stimulate a diuresis, and the washout pattern of isotope is monitored (time-activity histogram). Nonobstructive, obstructive, and poor renal function patterns were seen. Forty patients with varying degrees of hydroureteronephrosis were evaluated. Tracings were performed serially and compared with the clinical course in time, as well as with pressure flowmore » studies and operative findings. All patients with a nonobstructed diuretic renogram did well, except for 1 boy in whom ureteropelvic obstruction developed later. Difficulty in evaluating the obstructive renogram pattern occurred only in some children with severe (grade V) hydronephrosis. Further standardization of the diuretic renogram with regard to time of diuretic injection, state of patient hydration, and regions of imaging may improve diagnostic accuracy.« less

Antibody reactivity against Helicobacter pylori proteins in a sample of the Spanish adult population in 2008-2013.

PubMed

Fernández-de-Larrea, Nerea; Michel, Angelika; Romero, Beatriz; Butt, Julia; Pawlita, Michael; Pérez-Gómez, Beatriz; Castaño-Vinyals, Gemma; Moreno, Victor; Martín, Vicente; Amiano, Pilar; Castilla, Jesús; Fernández-Tardón, Guillermo; Dierssen-Sotos, Trinidad; Clofent, Juan; Alguacil, Juan; Huerta, José María; Jiménez-Moleón, José Juan; Barricarte, Aurelio; Molinuevo, Amaia; Fernández-Villa, Tania; Casabonne, Delphine; Sierra, Ángeles; Kogevinas, Manolis; de Sanjosé, Silvia; Pollán, Marina; Del Campo, Rosa; Waterboer, Tim; Aragonés, Nuria

2017-10-01

Differences in Helicobacter pylori protein expression have been related to the risk of severe gastric diseases. In Spain, a marked geographic pattern in gastric cancer mortality has long been reported. To characterize antibody reactivity patterns against 16 H. pylori proteins, by age, sex, and region of birth, in a large sample of the Spanish adult population. Antibody reactivity was quantified by H. pylori multiplex serology in a sample from the control group of the multicase-control study MCC-Spain. For this analysis, 2555 population-based controls were included. Each participant was classified as seropositive or seronegative for each protein according to specific cutoffs. Overall H. pylori seroprevalence was defined as positivity against ≥4 proteins. Descriptive analyses by age, sex, and region of birth were performed for both seroprevalence and seroreactivity (continuous measure). Differences among groups were tested by logistic and linear regression models. Overall H. pylori seroprevalence increased with age in both sexes. For ages 55-74, seroprevalence was lower in women than in men (84% vs 92%, P<.001). Region of birth explained 7% of the variability in seroprevalence. Among H. pylori seropositive subjects, proteins with the highest seroprevalence were GroEL, NapA, HP231, and Omp. Seropositivity for most of the proteins increased or remained stable with age, rising mainly for CagA, GroEL, and HyuA in women. A clear cohort effect was not observed. This is the first study to describe the antibody patterns against 16 H. pylori proteins in the Spanish population. We found variability in the H. pylori antibody profiles according to both individual factors such as age and sex, and environmental factors such as the region of birth. The slightness of the reduction in seropositivity with decreasing age highlights the ongoing importance of this infection. © 2017 John Wiley & Sons Ltd.

Comparison of pigment cell ultrastructure and organisation in the dermis of marble trout and brown trout, and first description of erythrophore ultrastructure in salmonids

PubMed Central

Djurdjevič, Ida; Kreft, Mateja Erdani; Sušnik Bajec, Simona

2015-01-01

Skin pigmentation in animals is an important trait with many functions. The present study focused on two closely related salmonid species, marble trout (Salmo marmoratus) and brown trout (S. trutta), which display an uncommon labyrinthine (marble-like) and spot skin pattern, respectively. To determine the role of chromatophore type in the different formation of skin pigment patterns in the two species, the distribution and ultrastructure of chromatophores was examined with light microscopy and transmission electron microscopy. The presence of three types of chromatophores in trout skin was confirmed: melanophores; xanthophores; and iridophores. In addition, using correlative microscopy, erythrophore ultrastructure in salmonids was described for the first time. Two types of erythrophores are distinguished, both located exclusively in the skin of brown trout: type 1 in black spot skin sections similar to xanthophores; and type 2 with a unique ultrastructure, located only in red spot skin sections. Morphologically, the difference between the light and dark pigmentation of trout skin depends primarily on the position and density of melanophores, in the dark region covering other chromatophores, and in the light region with the iridophores and xanthophores usually exposed. With larger amounts of melanophores, absence of xanthophores and presence of erythrophores type 1 and type L iridophores in the black spot compared with the light regions and the presence of erythrophores type 2 in the red spot, a higher level of pigment cell organisation in the skin of brown trout compared with that of marble trout was demonstrated. Even though the skin regions with chromatophores were well defined, not all the chromatophores were in direct contact, either homophilically or heterophilically, with each other. In addition to short-range interactions, an important role of the cellular environment and long-range interactions between chromatophores in promoting adult pigment pattern formation of trout are proposed. PMID:26467239

Comparison of pigment cell ultrastructure and organisation in the dermis of marble trout and brown trout, and first description of erythrophore ultrastructure in salmonids.

PubMed

Djurdjevič, Ida; Kreft, Mateja Erdani; Sušnik Bajec, Simona

2015-11-01

Skin pigmentation in animals is an important trait with many functions. The present study focused on two closely related salmonid species, marble trout (Salmo marmoratus) and brown trout (S. trutta), which display an uncommon labyrinthine (marble-like) and spot skin pattern, respectively. To determine the role of chromatophore type in the different formation of skin pigment patterns in the two species, the distribution and ultrastructure of chromatophores was examined with light microscopy and transmission electron microscopy. The presence of three types of chromatophores in trout skin was confirmed: melanophores; xanthophores; and iridophores. In addition, using correlative microscopy, erythrophore ultrastructure in salmonids was described for the first time. Two types of erythrophores are distinguished, both located exclusively in the skin of brown trout: type 1 in black spot skin sections similar to xanthophores; and type 2 with a unique ultrastructure, located only in red spot skin sections. Morphologically, the difference between the light and dark pigmentation of trout skin depends primarily on the position and density of melanophores, in the dark region covering other chromatophores, and in the light region with the iridophores and xanthophores usually exposed. With larger amounts of melanophores, absence of xanthophores and presence of erythrophores type 1 and type L iridophores in the black spot compared with the light regions and the presence of erythrophores type 2 in the red spot, a higher level of pigment cell organisation in the skin of brown trout compared with that of marble trout was demonstrated. Even though the skin regions with chromatophores were well defined, not all the chromatophores were in direct contact, either homophilically or heterophilically, with each other. In addition to short-range interactions, an important role of the cellular environment and long-range interactions between chromatophores in promoting adult pigment pattern formation of trout are proposed. © 2015 Anatomical Society.

Classification and Mapping of Agricultural Land for National Water-Quality Assessment

USGS Publications Warehouse

Gilliom, Robert J.; Thelin, Gail P.

1997-01-01

Agricultural land use is one of the most important influences on water quality at national and regional scales. Although there is great diversity in the character of agricultural land, variations follow regional patterns that are influenced by environmental setting and economics. These regional patterns can be characterized by the distribution of crops. A new approach to classifying and mapping agricultural land use for national water-quality assessment was developed by combining information on general land-use distribution with information on crop patterns from agricultural census data. Separate classification systems were developed for row crops and for orchards, vineyards, and nurseries. These two general categories of agricultural land are distinguished from each other in the land-use classification system used in the U.S. Geological Survey national Land Use and Land Cover database. Classification of cropland was based on the areal extent of crops harvested. The acreage of each crop in each county was divided by total row-crop area or total orchard, vineyard, and nursery area, as appropriate, thus normalizing the crop data and making the classification independent of total cropland area. The classification system was developed using simple percentage criteria to define combinations of 1 to 3 crops that account for 50 percent or more or harvested acreage in a county. The classification system consists of 21 level I categories and 46 level II subcategories for row crops, and 26 level I categories and 19 level II subcategories for orchards, vineyards, and nurseries. All counties in the United States with reported harvested acreage are classified in these categories. The distribution of agricultural land within each county, however, must be evaluated on the basis of general land-use data. This can be done at the national scale using 'Major Land Uses of the United States,' at the regional scale using data from the national Land Use and Land Cover database, or at smaller scales using locally available data.

Geologic Storage at the Basin Scale: Region-Based Basin Modeling, Powder River Basin (PRB), NE Wyoming and SE Montana

NASA Astrophysics Data System (ADS)

Melick, J. J.; Gardner, M. H.

2008-12-01

Carbon capture and storage from the over 2000 power plants is estimated at 3-5 GT/yr, which requires large- scale geologic storage of greenhouse gasses in sedimentary basins. Unfortunately, determination of basin scale storage capacity is currently based on oversimplified geologic models that are difficult to validate. Simplification involves reducing the number of geologic parameters incorporated into the model, modeling with large grid cells, and treatment of subsurface reservoirs as homogeneous media. The latter problem reflects the focus of current models on fluid and/or fluid-rock interactions rather than fluid movement and migration pathways. For example, homogeneous models over emphasize fluid behavior, like the buoyancy of super-critical CO2, and hence overestimate leakage rates. Fluid mixing and fluid-rock interactions cannot be assessed with models that only investigate these reactions at a human time scale. Preliminary and conservative estimates of the total pore volume for the PRB suggest 200 GT of supercritical CO2 can be stored in this typical onshore sedimentary basin. The connected pore volume (CPV) however is not included in this estimate. Geological characterization of the CPV relates subsurface storage units to the most prolific reservoir classes (RCs). The CPV, number of well penetrations, supercritical storage area, and potential leakage pathways characterize each RC. Within each RC, a hierarchy of stratigraphic cycles is populated with stationary sedimentation regions that control rock property distributions by correlating environment of deposition (EOD) to CPV. The degree to which CPV varies between RCs depends on the geology and attendant heterogeneity retained in the fluid flow model. Region-based modeling of the PRB incorporates 28000 wells correlated across a 70,000 Km2 area, 2 km thick on average. Within this basin, five of the most productive RCs were identified from production history and placed in a fourfold stratigraphic framework (second- through fourth-order cycles). Within the small- scale 4th-order sequences (30-150-m thick, 16 total), sedimentation regions, each corresponding to an EOD, are defined by thickness, lithology and core-calibrated well-log patterns. This talk illustrates the workflow by focusing on one of the 16 layers in the basin-scale model. Isopach maps from this sample layer conform to depositional patterns confirmed through definition of five core-calibrated, well-log defined sedimentation regions. Lithology distributions also conform to thickness trends in nearshore deltas, but not in offshore regions, where sand-rich and sheet-like, but thin-bedded sandstones are flanked by mud-rich intervals of equivalent thickness. These maps represent sedimentation patterns confined by basal erosional sequence boundary and basin-wide bentonite, yet containing up to seven high-frequency sequence boundaries. To illustrate over simplification problems in this same layer, a 14000 km2 sample area is 600 km3 and using standard averaging methods, which are considered to be geologic in origin, the CPV is 16 km3. However, averaging increases connectivity with high CPV more uniformly distributed; significantly, the key mud belt region separating nearshore from offshore sandstones is not represented. Region-based modeling of this layer yields 13 km3 (110 Bbl). Furthermore, significant vertical leakage may exist from the 20000 well penetrations and faults and fractures along the western basin margin. This example illustrates the importance of accurately characterizing heterogeneity and distributing CPV using sedimentation regions.

Fuzzy tree automata and syntactic pattern recognition.

PubMed

Lee, E T

1982-04-01

An approach of representing patterns by trees and processing these trees by fuzzy tree automata is described. Fuzzy tree automata are defined and investigated. The results include that the class of fuzzy root-to-frontier recognizable ¿-trees is closed under intersection, union, and complementation. Thus, the class of fuzzy root-to-frontier recognizable ¿-trees forms a Boolean algebra. Fuzzy tree automata are applied to processing fuzzy tree representation of patterns based on syntactic pattern recognition. The grade of acceptance is defined and investigated. Quantitative measures of ``approximate isosceles triangle,'' ``approximate elongated isosceles triangle,'' ``approximate rectangle,'' and ``approximate cross'' are defined and used in the illustrative examples of this approach. By using these quantitative measures, a house, a house with high roof, and a church are also presented as illustrative examples. In addition, three fuzzy tree automata are constructed which have the capability of processing the fuzzy tree representations of ``fuzzy houses,'' ``houses with high roofs,'' and ``fuzzy churches,'' respectively. The results may have useful applications in pattern recognition, image processing, artificial intelligence, pattern database design and processing, image science, and pictorial information systems.

Hydroclimate variability and regional atmospheric circulation over the past 1,350 years reconstructed from Lake Ohau, New Zealand

NASA Astrophysics Data System (ADS)

Roop, H. A.; Levy, R. H.; Vandergoes, M.; Dunbar, G. B.; Howarth, J. D.; Lorrey, A.; Phipps, S. J.

2016-12-01

Comprehensive understanding of natural climate-system dynamics requires high-resolution paleoclimate records extending beyond the instrumental period. This is particularly the case for the sparsely-instrumented Southern Hemisphere mid-latitudes, where the timing and amplitude of regional and hemispheric-scale climatic events are poorly constrained. Here we present a 1,350-year record of hydroclimatic variability and regional circulation derived from an annually laminated sediment record from Lake Ohau, South Island, New Zealand (44.23°S, 169.85°E). The climate of New Zealand is influenced by climatological patterns originating in both the tropics (e.g. El-Niño-Southern Oscillation, Interdecadal Pacific Oscillation) and the Antarctic (Southern Annular Mode, SAM). Utilizing the annually resolved Lake Ohau hydroclimate record in combination with a tree-ring record of summer temperature from Oroko Swamp, New Zealand (Cook et al., 2002), we generate a circulation index for the Western South Island of New Zealand. This index utilizes the temperature and precipitation anomalies defined by the Regional Climate Regime Classification scheme for New Zealand to assign synoptic scale circulation patterns to 25-year intervals from 900-2000 AD. This circulation index shows significant periods of change, most notably 835 - 985 AD when northerly airflow dominated and from 1385 - 1710 AD when strong southerly airflow persisted. Comparisons with regional SAM and ENSO reconstructions show that dry, warm conditions at Lake Ohau are consistently associated with strengthened tropical teleconnections to New Zealand and a positive SAM, while cold and wet conditions are driven by increased southerly airflow and negative phase SAM. A persistent negative SAM dominates the Little Ice Age (LIA; 1385-1710 AD) interval in the Western South Island. This same period coincides with the Northern Hemisphere LIA.

[Study on the area of pain and numbness in cases with lumbosacral radiculopathy].

PubMed

Kuraishi, Keita; Hanakita, Junya; Takahashi, Toshiyuki; Minami, Manabu; Watanabe, Mizuki; Uesaka, Toshio; Honda, Fumiaki

2012-10-01

In the clinical diagnosis of lumbosacral radicular symptoms, dermatome maps are commonly used, by which the segmental location of the affected nerve can be determined. However, the diagnosis is often difficult because the pattern of sensory disturbance does not necessarily match the patterns of classical dermatomes, and there are many dermatome maps made by different methods. The author examined the area of pain and numbness in cases of lumbosacral radiculopathy. Clinical features of pain and numbness in consecutive seventy three cases of lumbosacral radiculopathy were investigated (L3: n=13, L4-S1: n=20). Patients of L3 radiculopathy showed symptoms at the upper buttock and ventral surface of the thighs, knees and upper ventral surface of the legs. Patients of L4 radiculopathy showed symptoms at the ventro-lateral surfaces of the thigh and leg. The distinctive region, defined as the region having 100% superimposition, of L4 radiculopathy was the lateral part of the shin. Patients of L5 radiculopathy showed symptoms at the lateral surfaces of the thigh and leg. The distinctive region was the upper buttock. Patients of S1 radiculopathy showed symptoms at the lower buttock, dorso-lateral part of the leg and lateral part of the foot. The distinctive region was the lateral part of the calf. It was found that the regions of pain and numbness formed a continuous band-like zone from thigh to leg in 8% of L3, 45% of L4 and L5, and 35% of S1 radiculopathy. Using a visual analogue scale, the degree of leg pain was more severe than low back pain in 68% of the patients, but in 5% of patients, low back pain was more severe.

Beckwith-Wiedemann-like macroglossia and 18q23 haploinsufficiency.

PubMed

Lirussi, Frédéric; Jonard, Laurence; Gaston, Véronique; Sanlaville, Damien; Kooy, R Frank; Winnepenninckx, Birgitta; Maher, Eamonn R; Fitzpatrick, David R; Gicquel, Christine; Portnoï, Marie-France; Couderc, Rémy; Vazquez, Marie-Paule; Bahuau, Michel

2007-12-01

Beckwith-Wiedemann syndrome (BWS) is an overgrowth condition with tumor proclivity linked to a genetic imbalance of a complex imprinted region in 11p15.5. A female child with features fitting in with the BWS diagnostic framework and an apparent loss of imprinting (LOI) of the IGF2 gene in 11p15.5 was also reported to have a de novo chromosome 18q segmental deletion (Patient 1), thus pointing at the location of a possible trans-activating regulator element for maintenance of IGF2 imprinting and providing one of the few examples of locus heterogeneity of BWS. A second child with de novo 18q23 deletion and features of macroglossia, naevus flammeus, bilateral inguinal hernia and transient neonatal hypoglycemia, thus also fitting in with the BWS diagnostic framework, is here fully reported (Patient 2). In this child, an analysis of the BWS1 locus precluded any paternal isodisomy and showed a normal imprinting pattern (mono-allelic expression of IGF2 and normal H19 and CDKN1OT1/LIT1 methylation index). In Patients 1 and 2, deletions were shown to overlap, defining a minimal region of haplo-insufficiency of 3.8-5.6 Mb in 18q23. We conclude that this region provides a candidate location for an original macroglossia condition with strong overlap with BWS, but without obvious upstream functional relationship with the BWS1 locus in 11p15.5. Because this minimal region of haplo-insufficiency falls into a common region of deletion in 18q- syndrome, we inferred that this macroglossia condition would follow a recessive pattern of inheritance. (c) 2007 Wiley-Liss, Inc.

Shape-Morphing Materials from Stimuli-Responsive Hydrogel Hybrids.

PubMed

Jeon, Seog-Jin; Hauser, Adam W; Hayward, Ryan C

2017-02-21

The formation of well-defined and functional three-dimensional (3D) structures by buckling of thin sheets subjected to spatially nonuniform stresses is common in biological morphogenesis and has become a subject of great interest in synthetic systems, as such programmable shape-morphing materials hold promise in areas including drug delivery, biomedical devices, soft robotics, and biomimetic systems. Given their ability to undergo large changes in swelling in response to a wide variety of stimuli, hydrogels have naturally emerged as a key type of material in this field. Of particular interest are hybrid systems containing rigid inclusions that can define both the anisotropy and spatial nonuniformity of swelling as well as nanoparticulate additives that can enhance the responsiveness and functionality of the material. In this Account, we discuss recent progress in approaches to achieve well-defined shape morphing in hydrogel hybrids. First, we provide an overview of materials and methods that facilitate fabrication of such systems and outline the geometry and mechanics behind shape morphing of thin sheets. We then discuss how patterning of stiff inclusions within soft responsive hydrogels can be used to program both bending and swelling, thereby providing access to a wide array of complex 3D forms. The use of discretely patterned stiff regions to provide an effective composite response offers distinct advantages in terms of scalability and ease of fabrication compared with approaches based on smooth gradients within a single layer of responsive material. We discuss a number of recent advances wherein control of the mechanical properties and geometric characteristics of patterned stiff elements enables the formation of 3D shapes, including origami-inspired structures, concatenated helical frameworks, and surfaces with nonzero Gaussian curvature. Next, we outline how the inclusion of functional elements such as nanoparticles can enable unique pathways to programmable and even reprogrammable shape-morphing materials. We focus to a large extent on photothermally reprogrammable systems that include one of a variety of additives that serve to efficiently absorb light and convert it into heat, thereby driving the response of a temperature-sensitive hydrogel. Such systems are advantageous in that patterns of light can be defined with very high spatial and temporal resolution in addition to offering the potential for wavelength-selective addressability of multiple different inclusions. We highlight recent advances in the preparation of light-responsive hybrid systems capable of undergoing reprogrammable bending and buckling into well-defined 3D shapes. In addition, we describe several examples where shape tuning of hybrid systems enables control over the motion of responsive hydrogel-based materials. Finally, we offer our perspective on open challenges and future areas of interest for the field.

Characterising private and shared signatures of positive selection in 37 Asian populations.

PubMed

Liu, Xuanyao; Lu, Dongsheng; Saw, Woei-Yuh; Shaw, Philip J; Wangkumhang, Pongsakorn; Ngamphiw, Chumpol; Fucharoen, Suthat; Lert-Itthiporn, Worachart; Chin-Inmanu, Kwanrutai; Chau, Tran Nguyen Bich; Anders, Katie; Kasturiratne, Anuradhani; de Silva, H Janaka; Katsuya, Tomohiro; Kimura, Ryosuke; Nabika, Toru; Ohkubo, Takayoshi; Tabara, Yasuharu; Takeuchi, Fumihiko; Yamamoto, Ken; Yokota, Mitsuhiro; Mamatyusupu, Dolikun; Yang, Wenjun; Chung, Yeun-Jun; Jin, Li; Hoh, Boon-Peng; Wickremasinghe, Ananda R; Ong, RickTwee-Hee; Khor, Chiea-Chuen; Dunstan, Sarah J; Simmons, Cameron; Tongsima, Sissades; Suriyaphol, Prapat; Kato, Norihiro; Xu, Shuhua; Teo, Yik-Ying

2017-04-01

The Asian Diversity Project (ADP) assembled 37 cosmopolitan and ethnic minority populations in Asia that have been densely genotyped across over half a million markers to study patterns of genetic diversity and positive natural selection. We performed population structure analyses of the ADP populations and divided these populations into four major groups based on their genographic information. By applying a highly sensitive algorithm haploPS to locate genomic signatures of positive selection, 140 distinct genomic regions exhibiting evidence of positive selection in at least one population were identified. We examined the extent of signal sharing for regions that were selected in multiple populations and observed that populations clustered in a similar fashion to that of how the ancestry clades were phylogenetically defined. In particular, populations predominantly located in South Asia underwent considerably different adaptation as compared with populations from the other geographical regions. Signatures of positive selection present in multiple geographical regions were predicted to be older and have emerged prior to the separation of the populations in the different regions. In contrast, selection signals present in a single population group tended to be of lower frequencies and thus can be attributed to recent evolutionary events.

Characterising private and shared signatures of positive selection in 37 Asian populations

PubMed Central

Liu, Xuanyao; Lu, Dongsheng; Saw, Woei-Yuh; Shaw, Philip J; Wangkumhang, Pongsakorn; Ngamphiw, Chumpol; Fucharoen, Suthat; Lert-itthiporn, Worachart; Chin-inmanu, Kwanrutai; Chau, Tran Nguyen Bich; Anders, Katie; Kasturiratne, Anuradhani; de Silva, H Janaka; Katsuya, Tomohiro; Kimura, Ryosuke; Nabika, Toru; Ohkubo, Takayoshi; Tabara, Yasuharu; Takeuchi, Fumihiko; Yamamoto, Ken; Yokota, Mitsuhiro; Mamatyusupu, Dolikun; Yang, Wenjun; Chung, Yeun-Jun; Jin, Li; Hoh, Boon-Peng; Wickremasinghe, Ananda R; Ong, RickTwee-Hee; Khor, Chiea-Chuen; Dunstan, Sarah J; Simmons, Cameron; Tongsima, Sissades; Suriyaphol, Prapat; Kato, Norihiro; Xu, Shuhua; Teo, Yik-Ying

2017-01-01

The Asian Diversity Project (ADP) assembled 37 cosmopolitan and ethnic minority populations in Asia that have been densely genotyped across over half a million markers to study patterns of genetic diversity and positive natural selection. We performed population structure analyses of the ADP populations and divided these populations into four major groups based on their genographic information. By applying a highly sensitive algorithm haploPS to locate genomic signatures of positive selection, 140 distinct genomic regions exhibiting evidence of positive selection in at least one population were identified. We examined the extent of signal sharing for regions that were selected in multiple populations and observed that populations clustered in a similar fashion to that of how the ancestry clades were phylogenetically defined. In particular, populations predominantly located in South Asia underwent considerably different adaptation as compared with populations from the other geographical regions. Signatures of positive selection present in multiple geographical regions were predicted to be older and have emerged prior to the separation of the populations in the different regions. In contrast, selection signals present in a single population group tended to be of lower frequencies and thus can be attributed to recent evolutionary events. PMID:28098149

Changes of precipitation extremes indices in São Francisco River Basin, Brazil from 1947 to 2012

NASA Astrophysics Data System (ADS)

Bezerra, Bergson G.; Silva, Lindenberg L.; Santos e Silva, Claudio M.; de Carvalho, Gilvani Gomes

2018-02-01

The São Francisco River is strategically important due to its hydroelectric potential and for bringing the largest water body of Brazilian Semiarid region, supplying water for irrigation, urban, and industrial activities. Thereby, for the purpose of characterizing changes on the precipitation patterns over São Francisco River basin, 11 extremes precipitation indices as defined by the joint WMO/CCI/ETCCDMI/CLIVAR project were calculated using daily observation from the 59 rain gauges during 1947-2012 period. The extreme climatic indices were calculated with the RClimDex software, which performs an exhaustive data quality control, intending to identify spurious errors and dataset inconsistencies. Weak and significant regional changes were observed in both CDD and SDII indices. Most precipitation extremes indices decreased but without statistical significance. The spatial analysis of indices did not show clearly regional changes due to the complexity of hydrometeorology of the region. In some cases, two rainfall stations exhibited opposite trends with the same significance level although they are separated by a few kilometers. This has occurred more frequently in Lower-Middle São Francisco, probably associated with intense land cover change over the last decades in this region.

Phenologically distinct phytoplankton regions on the Faroe Shelf - identified by satellite data, in-situ observations and model

NASA Astrophysics Data System (ADS)

Eliasen, Sólvá Káradóttir; Hátún, Hjálmar; Larsen, Karin Margretha H.; Hansen, Bogi; Rasmussen, Till Andreas S.

2017-05-01

Marked inter-annual fluctuations in the primary production on the Faroe shelf propagate to higher trophic levels and influence commercial fish stocks. This has previously been demonstrated based on weekly chlorophyll samples from a coastal station, dating back to 1997. However, the spatial extent, for which the coastal samples are representative, has not been well defined, and potential bio-geographical segregations of the shelf have not been considered. By integrating 18 years of chlorophyll satellite data, supplemented by in-situ, model, and meteorological reanalysis data, we identify three regions with unique characteristics with regards to surface chlorophyll and vertical structure - the Central Shelf, the Outer Shelf and the Eastern Banks. The observed difference in timing of the spring bloom in these regions helps explain different spawning patterns of important fish stocks, and the spatial division of the Faroe Shelf should be considered when studying biology and hydrography in these waters. A positive correlation between annual means on the outer Faroe Shelf and parts of the outer northwest Scottish Shelf indicates similarities between these neighbouring regions. We suggest that this similarity arises from the commonality in nutrient composition of the water masses shared by these neighbouring regions.

Clinicopathological patterns and distribution of Schistosomiasis in Asir Region.

PubMed

Morad, N A; Khan, A R

2001-06-01

The objective of this study is to report, for the first time, the histopathologic pattern of Schistosomiasis from the Asir Region and to compare it to patterns reported from other regions of the Kingdom of Saudi Arabia. Several studies have reported the patterns of Schistosomiasis in other regions of the Kingdom of Saudi Arabia and other countries where Schistosomiasis is endemic. Schistosomiasis is endemic in certain areas of Asir region, however no data is available concerning the clinicopathological pattern of Schistosomiasis in the Asir Region. This is a retrospective analysis of 217 cases of Schistosomiasis from surgical and biopsy files of Asir Central Hospital during a period from January 1990 to October 1999. Our study revealed that Schistosomiasis was more common among the expatriate population of Asir Region than Saudi nationals residing in this area. The urinary tract was most commonly involved, and then in descending frequency came the vermiform appendix, liver and large bowel. These findings are somewhat different from those observed in the Riyadh Region where the vermiform appendix was the most commonly affected organ. Based on the histopathologic pattern, our study describes the pattern of Schistosomiasis in the Asir Region and may serve as a base-line for future research work.

Map and Database of Probable and Possible Quaternary Faults in Afghanistan

USGS Publications Warehouse

Ruleman, C.A.; Crone, A.J.; Machette, M.N.; Haller, K.M.; Rukstales, K.S.

2007-01-01

The U.S. Geological Survey (USGS) with support from the U.S. Agency for International Development (USAID) mission in Afghanistan, has prepared a digital map showing the distribution of probable and suspected Quaternary faults in Afghanistan. This map is a key component of a broader effort to assess and map the country's seismic hazards. Our analyses of remote-sensing imagery reveal a complex array of tectonic features that we interpret to be probable and possible active faults within the country and in the surrounding border region. In our compilation, we have mapped previously recognized active faults in greater detail, and have categorized individual features based on their geomorphic expression. We assigned mapped features to eight newly defined domains, each of which contains features that appear to have similar styles of deformation. The styles of deformation associated with each domain provide insight into the kinematics of the modern tectonism, and define a tectonic framework that helps constrain deformational models of the Alpine-Himalayan orogenic belt. The modern fault movements, deformation, and earthquakes in Afghanistan are driven by the collision between the northward-moving Indian subcontinent and Eurasia. The patterns of probable and possible Quaternary faults generally show that much of the modern tectonic activity is related to transfer of plate-boundary deformation across the country. The left-lateral, strike-slip Chaman fault in southeastern Afghanistan probably has the highest slip rate of any fault in the country; to the north, this slip is distributed onto several fault systems. At the southern margin of the Kabul block, the style of faulting changes from mainly strike-slip motion associated with the boundary between the Indian and Eurasian plates, to transpressional and transtensional faulting. North and northeast of the Kabul block, we recognized a complex pattern of potentially active strike-slip, thrust, and normal faults that form a conjugate shear system in a transpressional region of the Trans-Himalayan orogenic belt. The general patterns and orientations of faults and the styles of deformation that we interpret from the imagery are consistent with the styles of faulting determined from focal mechanisms of historical earthquakes. Northwest-trending strike-slip fault zones are cut and displaced by younger, southeast-verging thrust faults; these relations define the interaction between northwest-southeast-oriented contraction and northwest-directed extrusion in the western Himalaya, Pamir, and Hindu Kush regions. Transpression extends into north-central Afghanistan where north-verging contraction along the east-west-trending Alburz-Marmul fault system interacts with northwest-trending strike-slip faults. Pressure ridges related to thrust faulting and extensional basins bounded by normal faults are located at major stepovers in these northwest-trending strike-slip systems. In contrast, young faulting in central and western Afghanistan indicates that the deformation is dominated by extension where strike-slip fault zones transition into regions of normal faults. In addition to these initial observations, our digital map and database provide a foundation that can be expanded, complemented, and modified as future investigations provide more detailed information about the location, characteristics, and history of movement on Quaternary faults in Afghanistan.

Orthostatic hypotension, cerebral hypoperfusion, and visuospatial deficits in Lewy body disorders.

PubMed

Robertson, Andrew D; Messner, Michelle A; Shirzadi, Zahra; Kleiner-Fisman, Galit; Lee, Joyce; Hopyan, Julia; Lang, Anthony E; Black, Sandra E; MacIntosh, Bradley J; Masellis, Mario

2016-01-01

Orthostatic hypotension and cognitive impairment are two non-motor attributes of Lewy body spectrum disorders that impact independence. This proof-of-concept study examined cerebral blood flow (perfusion) as a mediator of orthostatic hypotension and cognition. In fifteen patients with Lewy body disorders, we estimated regional perfusion using pseudo-continuous arterial spin labeling MRI, and quantified orthostatic hypotension from the change in systolic blood pressure between supine and standing positions. Executive, visuospatial, attention, memory, and language domains were characterized by neuropsychological tests. A matching sample of non-demented adults with cerebral small vessel disease was obtained to contrast perfusion patterns associated with comorbid vascular pathology. Compared to the vascular group, patients with Lewy body disorders exhibited lower perfusion to temporal and occipital lobes than to frontal and parietal lobes (q < 0.05). A greater orthostatic drop in systolic pressure was associated with lower occipito-parietal perfusion in these patients (uncorrected p < 0.005; cluster size ≥ 20 voxels). Although orthostatic hypotension and supine hypertension were strongly correlated (r = -0.79, p < 0.001), the patterns of association for each with perfusion were distinct. Specifically, supine hypertension was associated with high perfusion to anterior and middle cerebral arterial territories, as well as with low perfusion to posterior regions. Perfusion within orthostatic hypotension-defined regions was directly related to performance on visuospatial and attention tasks, independent of dementia severity (p < 0.05). These findings provide new insight that regional cerebral hypoperfusion is related to orthostatic hypotension, and may be involved in domain-specific cognitive deficits in Lewy body disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

Topologically convergent and divergent structural connectivity patterns between patients with remitted geriatric depression and amnestic mild cognitive impairment.

PubMed

Bai, Feng; Shu, Ni; Yuan, Yonggui; Shi, Yongmei; Yu, Hui; Wu, Di; Wang, Jinhui; Xia, Mingrui; He, Yong; Zhang, Zhijun

2012-03-21

Alzheimer's disease (AD) can be conceptualized as a disconnection syndrome. Both remitted geriatric depression (RGD) and amnestic mild cognitive impairment (aMCI) are associated with a high risk for developing AD. However, little is known about the similarities and differences in the topological patterns of white matter (WM) structural networks between RGD and aMCI. In this study, diffusion tensor imaging and deterministic tractography were used to map the human WM networks of 35 RGD patients, 38 aMCI patients, and 30 healthy subjects. Furthermore, graph theoretical methods were applied to investigate the alterations in the global and regional properties of the WM network in these patients. First, both the RGD and aMCI patients showed abnormal global topology in their WM networks (i.e., reduced network strength, reduced global efficiency, and increased absolute path length) compared with the controls, and there were no significant differences in these global network properties between the patient groups. Second, similar deficits of the regional and connectivity characteristics in the WM networks were primarily found in the frontal brain regions of RGD and aMCI patients compared with the controls, while a different nodal efficiency of the posterior cingulate cortex and several prefrontal brain regions were also observed between the patient groups. Together, our study provides direct evidence for the association of a great majority of convergent and a minority of divergent connectivity of WM structural networks between RGD and aMCI patients, which may lead to increasing attention in defining a population at risk of AD.

Spatiotemporal Discordance in Five Common Measures of Rurality for US Counties and Applications for Health Disparities Research in Older Adults.

PubMed

Cohen, Steven A; Kelley, Lauren; Bell, Allison E

2015-01-01

Rural populations face numerous barriers to health, including poorer health care infrastructure, access to care, and other sociodemographic factors largely associated with rurality. Multiple measures of rurality used in the biomedical and public health literature can help assess rural-urban health disparities and may impact the observed associations between rurality and health. Furthermore, understanding what makes a place truly "rural" versus "urban" may vary from region to region in the US. The objectives of this study are to compare and contrast five common measures of rurality and determine how well-correlated these measures are at the national, regional, and divisional level, as well as to assess patterns in the correlations between the prevalence of obesity in the population aged 60+ and each of the five measures of rurality at the regional and divisional level. Five measures of rurality were abstracted from the US Census and US Department of Agriculture (USDA) to characterize US counties. Obesity data in the population aged 60+ were abstracted from the Behavioral Risk Factor Surveillance System (BRFSS). Spearman's rank correlations were used to quantify the associations among the five rurality measurements at the national, regional, and divisional level, as defined by the US Census Bureau. Geographic information systems were used to visually illustrate temporal, spatial, and regional variability. Overall, Spearman's rank correlations among the five measures ranged from 0.521 (percent urban-urban influence code) to 0.917 (rural-urban continuum code-urban influence code). Notable discrepancies existed in these associations by Census region and by division. The associations between measures of rurality and obesity in the 60+ population varied by rurality measure used and by region. This study is among the first to systematically assess the spatial, temporal, and regional differences and similarities among five commonly used measures of rurality in the US. There are important, quantifiable distinctions in defining what it means to be a rural county depending on both the geographic region and the measurement used. These findings highlight the importance of developing and selecting an appropriate rurality metric in health research.

Patterns of abuse amongst Sri Lankan women returning home after working as domestic maids in the Middle East: An exploratory study of medico-legal referrals.

PubMed

Wickramage, Kolitha; De Silva, Malintha; Peiris, Sharika

2017-01-01

Migrant worker abuse is well recognised, but poorly characterised within the scientific literature. This study aimed to explore patterns of abuse amongst Sri Lankan women returning home after working as domestic maids. Sri Lanka has over 2 million of its citizens employed overseas as international labor migrants. A cross-sectional study was conducted on Sri Lankan female domestic maids returning from the Middle East region who were referred for medico-legal opinion. A total of 20 women were included in the study. Average length of their employment overseas was 14 months. Complaints of physical violence directed mainly through their employers were made by 60% of women. Upon physical examination, two-thirds had evidence of injuries, with a third being subjected to repetitive/systematic violence. Eighty percent suffered some form of psychological trauma. Personal identity papers and travel documents had been confiscated by the employer in 85% of cases, with two thirds indicating they were prevented and/or restricted from leaving their place of work/residence. Our study demonstrates that female domestic maid abuse manifests through multiple pathways. Violence against such workers span the full spectrum of physical, financial, verbal, emotional abuse and neglect, as defined by the World Health Organization. Findings from this exploratory study cannot be generalized to the large volume of migrant worker outflows. Further research is needed to determine incidence and define patterns in other migrant worker categories such as low-skilled male workers. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

9 CFR 94.10 - Swine from regions where classical swine fever exists.

Code of Federal Regulations, 2010 CFR

2010-01-01

...-defined EU CSF region is a single region of low-risk for CSF. (c) Except as provided in § 94.24 for the APHIS-defined EU CSF region, no swine that are moved from or transit any region where classical swine...

Universal Pin Electronics.

DTIC Science & Technology

1982-11-03

define the maximum count for the pattern defined by the first 3 bits. Since there are 11 bits involved it is possible to define patterns up to 2048 ...applied to the UUT directly through the driver for any count up to 2048 . Any one of the 7 clocks may be selected under program control and applied to any...one ievel for the driver ( VDI ), the logic zero level for the driver (VDO), the logic one level for the receiver (VRl), and the logic zero level for the

Single-Nucleosome Mapping of Histone Modifications in S. cerevisiae

PubMed Central

Kim, Minkyu; Buratowski, Stephen; Schreiber, Stuart L; Friedman, Nir

2005-01-01

Covalent modification of histone proteins plays a role in virtually every process on eukaryotic DNA, from transcription to DNA repair. Many different residues can be covalently modified, and it has been suggested that these modifications occur in a great number of independent, meaningful combinations. Published low-resolution microarray studies on the combinatorial complexity of histone modification patterns suffer from confounding effects caused by the averaging of modification levels over multiple nucleosomes. To overcome this problem, we used a high-resolution tiled microarray with single-nucleosome resolution to investigate the occurrence of combinations of 12 histone modifications on thousands of nucleosomes in actively growing S. cerevisiae. We found that histone modifications do not occur independently; there are roughly two groups of co-occurring modifications. One group of lysine acetylations shows a sharply defined domain of two hypo-acetylated nucleosomes, adjacent to the transcriptional start site, whose occurrence does not correlate with transcription levels. The other group consists of modifications occurring in gradients through the coding regions of genes in a pattern associated with transcription. We found no evidence for a deterministic code of many discrete states, but instead we saw blended, continuous patterns that distinguish nucleosomes at one location (e.g., promoter nucleosomes) from those at another location (e.g., over the 3′ ends of coding regions). These results are consistent with the idea of a simple, redundant histone code, in which multiple modifications share the same role. PMID:16122352

Vertebrate endemism in south-eastern Africa numerically redefines a biodiversity hotspot.

PubMed

Perera, Sandun J; ProcheŞ, Şerban; Ratnayake-Perera, Dayani; Ramdhani, Syd

2018-02-20

We use numerical methods to explore patterns of vertebrate endemism in south-eastern Africa, refining the boundaries of the intuitively-defined Maputaland-Pondoland-Albany biodiversity hotspot, also proposing a zoogeographic regionalisation. An incidence matrix of 300 vertebrate species endemic to south-eastern Africa sensu lato in 37 operational geographic units were used in (a) phenetic cluster analysis (PCA) using the algorithm of unweighted pair-group method with arithmetic averages (phenetic approach), and (b) parsimony analysis of endemicity (PAE; parsimony approach), in order to numerically evaluate the bioregional delimitations. The analyses provide a valid biogeographical entity 37% larger than the Maputaland-Pondoland-Albany hotspot, but substantially (131%) higher in vertebrate endemicity viz. the Greater Maputaland-Pondoland-Albany (GMPA) region of vertebrate endemism. South-east Africa is recognised as a dominion in the global zoogeographical area hierarchy, with subordinate units including the GMPA province. Various spatially-based measures of endemism were mapped for vertebrate species restricted to the dominion, i.e. endemic to south-eastern Africa sensu stricto. Areas and centres of endemism detected respectively from PAE and PCA, within the south-east Africa dominion also support the refined boundary of the GMPA region of endemism, which provides a better spatial conservation priority compared to the Maputaland-Pondoland-Albany hotspot. Reptiles and amphibians are found to be the main drivers of the overall pattern of endemism, while the pattern in freshwater fish is the most distinctive. Our analyses also indicate a good congruence of the centres of endemism across different terrestrial vertebrate taxa.

Geologic structures related to New Madrid earthquakes near Memphis, Tennessee, based on gravity and magnetic interpretations

USGS Publications Warehouse

Hildenbrand, T.G.; Stuart, W.D.; Talwani, P.

2001-01-01

New inversions of gravity and magnetic data in the region north of memphis. Tennessee, and south of latitude 36?? define boundaries of regional structures and igneous complexes in the upper crust. Microseismicity patterns near interpreted boundaries suggest that igneous complexes influence the locations of microseismicity. A weak seismicity cluster occurs near one intrusion (Covington pluton), at the intersection of the southwest margin of the Missouri batholith and the southeast margin of the Reelfoot rift. A narrow seismicity trend along the Reelfoot rift axis becomes diffuse near a second intrusion (Osceola intrusive complex) and changes direction to an area along the northwest flank of the intrusion. The axial seismicity trend also contains a tight cluster of earthquakes located just outside the Osceola intrusive complex. The mechanical explanation of the two seismicity patterns is uncertain, but the first cluster may be caused by stress concentration due to the high elastic stiffness and strength of the Covington intrusion. The spatially changing seismicity pattern near the Osceola complex may be caused by the preceding factors plus interaction with faulting along the rift axis. The axial seismicity strand itself is one of several connected and interacting active strands that may produce stress concentrations at strand ends and junctions. The microseismicity clusters at the peripheries of the two intrusions lead us to conclude that these stress concentrations or stressed volumes may be locations of future moderate to large earthquakes near Memphis. Published by Elsevier Science B.V.

Regional-Scale Drivers of Forest Structure and Function in Northwestern Amazonia

PubMed Central

Higgins, Mark A.; Asner, Gregory P.; Anderson, Christopher B.; Martin, Roberta E.; Knapp, David E.; Tupayachi, Raul; Perez, Eneas; Elespuru, Nydia; Alonso, Alfonso

2015-01-01

Field studies in Amazonia have found a relationship at continental scales between soil fertility and broad trends in forest structure and function. Little is known at regional scales, however, about how discrete patterns in forest structure or functional attributes map onto underlying edaphic or geological patterns. We collected airborne LiDAR (Light Detection and Ranging) data and VSWIR (Visible to Shortwave Infrared) imaging spectroscopy measurements over 600 km2 of northwestern Amazonian lowland forests. We also established 83 inventories of plant species composition and soil properties, distributed between two widespread geological formations. Using these data, we mapped forest structure and canopy reflectance, and compared them to patterns in plant species composition, soils, and underlying geology. We found that variations in soils and species composition explained up to 70% of variation in canopy height, and corresponded to profound changes in forest vertical profiles. We further found that soils and plant species composition explained more than 90% of the variation in canopy reflectance as measured by imaging spectroscopy, indicating edaphic and compositional control of canopy chemical properties. We last found that soils explained between 30% and 70% of the variation in gap frequency in these forests, depending on the height threshold used to define gaps. Our findings indicate that a relatively small number of edaphic and compositional variables, corresponding to underlying geology, may be responsible for variations in canopy structure and chemistry over large expanses of Amazonian forest. PMID:25793602

The Epidemiology of Global Epilepsy.

PubMed

Singh, Anuradha; Trevick, Stephen

2016-11-01

The International League Against Epilepsy defines epilepsy as at least 2 unprovoked seizures more than 24 hours apart. It is a wide-reaching and complex illness affecting more than 70 million people worldwide and can take on a variety of forms, patterns, and severities. Geographic differences in the illness are often related to its etiology. A host of endemic illnesses and parasitic infections can lead to epilepsy syndromes. Management varies by region due to the availability of diagnostic modalities and medications. Treatment gaps in epilepsy care often are related to social and cultural factors that must also be understood. Copyright © 2016 Elsevier Inc. All rights reserved.

Revealing representational content with pattern-information fMRI--an introductory guide.

PubMed

Mur, Marieke; Bandettini, Peter A; Kriegeskorte, Nikolaus

2009-03-01

Conventional statistical analysis methods for functional magnetic resonance imaging (fMRI) data are very successful at detecting brain regions that are activated as a whole during specific mental activities. The overall activation of a region is usually taken to indicate involvement of the region in the task. However, such activation analysis does not consider the multivoxel patterns of activity within a brain region. These patterns of activity, which are thought to reflect neuronal population codes, can be investigated by pattern-information analysis. In this framework, a region's multivariate pattern information is taken to indicate representational content. This tutorial introduction motivates pattern-information analysis, explains its underlying assumptions, introduces the most widespread methods in an intuitive way, and outlines the basic sequence of analysis steps.

Dietary patterns in internal migrants in a continental country: A population-based study.

PubMed

Carioca, Antonio Augusto Ferreira; Gorgulho, Bartira; Teixeira, Juliana Araujo; Fisberg, Regina Mara; Marchioni, Dirce Maria

2017-01-01

The objective of this study was to assess the differences and similarities in dietary patterns among migrants and natives. A population-based, cross-sectional study was conducted in the city of São Paulo. The study population included internal migrants, defined as individuals born outside São Paulo city who had lived in the city for ten years or longer. The final population (n = 999) was divided into three groups: natives of São Paulo (n = 354), migrants from the Southeast (n = 349) and migrants from the Northeast (n = 296). Factor and principal component analysis was employed to derive dietary patterns. The standardized scores were compared among groups using linear regression. Differences in income per capita, years of education, self-reported race, smoking habits, alcohol consumption, nutritional status and prevalence of hypertension were found for place of birth. Three dietary patterns were identified: prudent (salad dressings, vegetables, natural flavorings, fruits, whole-grain bread, white cheeses and juices), traditional (rice, beans, bread/toast/crackers, butter/margarine, whole milk, coffee/teas, sugar), and modern (sodas, pastries/sandwiches/pizzas, yellow cheeses, pastas, sauces, alcoholic beverages, sweets, processed meats). Compared to natives, migrants from the Southeast had an inversely proportional adherence to the modern pattern whereas migrants from the Northeast had an inverse association with the prudent and modern patterns and a positive association with the traditional pattern. São Paulo natives and internal migrants from other regions of Brazil exhibited different dietary patterns. The results presented here add perspectives to be considered in the study of non-communicable diseases and its different incidences among migrants and natives.

Incremental terrain processing for large digital elevation models

NASA Astrophysics Data System (ADS)

Ye, Z.

2012-12-01

Incremental terrain processing for large digital elevation models Zichuan Ye, Dean Djokic, Lori Armstrong Esri, 380 New York Street, Redlands, CA 92373, USA (E-mail: zye@esri.com, ddjokic@esri.com , larmstrong@esri.com) Efficient analyses of large digital elevation models (DEM) require generation of additional DEM artifacts such as flow direction, flow accumulation and other DEM derivatives. When the DEMs to analyze have a large number of grid cells (usually > 1,000,000,000) the generation of these DEM derivatives is either impractical (it takes too long) or impossible (software is incapable of processing such a large number of cells). Different strategies and algorithms can be put in place to alleviate this situation. This paper describes an approach where the overall DEM is partitioned in smaller processing units that can be efficiently processed. The processed DEM derivatives for each partition can then be either mosaicked back into a single large entity or managed on partition level. For dendritic terrain morphologies, the way in which partitions are to be derived and the order in which they are to be processed depend on the river and catchment patterns. These patterns are not available until flow pattern of the whole region is created, which in turn cannot be established upfront due to the size issues. This paper describes a procedure that solves this problem: (1) Resample the original large DEM grid so that the total number of cells is reduced to a level for which the drainage pattern can be established. (2) Run standard terrain preprocessing operations on the resampled DEM to generate the river and catchment system. (3) Define the processing units and their processing order based on the river and catchment system created in step (2). (4) Based on the processing order, apply the analysis, i.e., flow accumulation operation to each of the processing units, at the full resolution DEM. (5) As each processing unit is processed based on the processing order defined in (3), compare the resulting drainage pattern with the drainage pattern established at the coarser scale and adjust the drainage boundaries and rivers if necessary.

9 CFR 94.10 - Swine from regions where classical swine fever exists.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Pacific Islands. (b) The APHIS-defined EU CSF region is a single region of low-risk for CSF. (c) Except as provided in § 94.24 for the APHIS-defined EU CSF region, no swine that are moved from or transit any region...

Unravelling the Intrinsic Functional Organization of the Human Striatum: A Parcellation and Connectivity Study Based on Resting-State fMRI

PubMed Central

Jung, Wi Hoon; Jang, Joon Hwan; Park, Jin Woo; Kim, Euitae; Goo, Eun-Hoe; Im, Oh-Soo; Kwon, Jun Soo

2014-01-01

As the main input hub of the basal ganglia, the striatum receives projections from the cerebral cortex. Many studies have provided evidence for multiple parallel corticostriatal loops based on the structural and functional connectivity profiles of the human striatum. A recent resting-state fMRI study revealed the topography of striatum by assigning each voxel in the striatum to its most strongly correlated cortical network among the cognitive, affective, and motor networks. However, it remains unclear what patterns of striatal parcellation would result from performing the clustering without subsequent assignment to cortical networks. Thus, we applied unsupervised clustering algorithms to parcellate the human striatum based on its functional connectivity patterns to other brain regions without any anatomically or functionally defined cortical targets. Functional connectivity maps of striatal subdivisions, identified through clustering analyses, were also computed. Our findings were consistent with recent accounts of the functional distinctions of the striatum as well as with recent studies about its functional and anatomical connectivity. For example, we found functional connections between dorsal and ventral striatal clusters and the areas involved in cognitive and affective processes, respectively, and between rostral and caudal putamen clusters and the areas involved in cognitive and motor processes, respectively. This study confirms prior findings, showing similar striatal parcellation patterns between the present and prior studies. Given such striking similarity, it is suggested that striatal subregions are functionally linked to cortical networks involving specific functions rather than discrete portions of cortical regions. Our findings also demonstrate that the clustering of functional connectivity patterns is a reliable feature in parcellating the striatum into anatomically and functionally meaningful subdivisions. The striatal subdivisions identified here may have important implications for understanding the relationship between corticostriatal dysfunction and various neurodegenerative and psychiatric disorders. PMID:25203441

Propagation of tau pathology: hypotheses, discoveries, and yet unresolved questions from experimental and human brain studies.

PubMed

Lewis, Jada; Dickson, Dennis W

2016-01-01

Tau is a microtubule-associated protein and a key regulator of microtubule stabilization as well as the main component of neurofibrillary tangles-a principle neuropathological hallmark of Alzheimer's disease (AD)-as well as pleomorphic neuronal and glial inclusions in neurodegenerative tauopathies. Cross-sectional studies of neurofibrillary pathology in AD reveal a stereotypic spatiotemporal pattern of neuronal vulnerability that correlates with disease severity; however, the relationship of this pattern to disease progression is less certain and exceptions to the typical pattern have been described in a subset of AD patients. The basis for the selective vulnerability of specific populations of neurons to tau pathology and cell death is largely unknown, although there have been a number of hypotheses based upon shared properties of vulnerable neurons (e.g., degree of axonal myelination or synaptic plasticity). A recent hypothesis for selective vulnerability takes into account the emerging science of functional connectivity based upon resting state functional magnetic resonance imaging, where subsets of neurons that fire synchronously define patterns of degeneration similar to specific neurodegenerative disorders, including various tauopathies. In the past 6 years, the concept of tau propagation has emerged from numerous studies in cell and animal models suggesting that tau moves from cell-to-cell and that this may trigger aggregation and region-to-region spread of tau pathology within the brain. How the spread of tau pathology relates to functional connectivity is an area of active investigation. Observations of templated folding and propagation of tau have prompted comparisons of tau to prions, the pathogenic proteins in transmissible spongiform encephalopathies. In this review, we discuss the most compelling studies in the field, discuss their shortcomings and consider their implications with respect to human tauopathies as well as the controversy that tauopathies may be prion-like disorders.

Representation of action in occipito-temporal cortex.

PubMed

Wiggett, Alison J; Downing, Paul E

2011-07-01

A fundamental question for social cognitive neuroscience is how and where in the brain the identities and actions of others are represented. Here we present a replication and extension of a study by Kable and Chatterjee [Kable, J. W., & Chatterjee, A. Specificity of action representations in the lateral occipito-temporal cortex. Journal of Cognitive Neuroscience, 18, 1498-1517, 2006] examining the role of occipito-temporal cortex in these processes. We presented full-cue movies of actors performing whole-body actions and used fMRI to test for action- and identity-specific adaptation effects. We examined a series of functionally defined regions, including the extrastriate and fusiform body areas, the fusiform face area, the parahippocampal place area, the lateral occipital complex, the right posterior superior temporal sulcus, and motion-selective area hMT+. These regions were analyzed with both standard univariate measures as well as multivoxel pattern analyses. Additionally, we performed whole-brain tests for significant adaptation effects. We found significant action-specific adaptation in many areas, but no evidence for identity-specific adaptation. We argue that this finding could be explained by differences in the familiarity of the stimuli presented: The actions shown were familiar but the actors performing the actions were unfamiliar. However, in contrast to previous findings, we found that the action adaptation effect could not be conclusively tied to specific functionally defined regions. Instead, our results suggest that the adaptation to previously seen actions across identities is a widespread effect, evident across lateral and ventral occipito-temporal cortex.

Sensitivity of Vadose Zone Water Fluxes to Climate Shifts in Arid Settings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pfletschinger, H.; Prömmel, K.; Schüth, C.

2014-01-01

Vadose zone water fluxes in arid settings are investigated regarding their sensitivity to hydraulic soil parameters and meteorological data. The study is based on the inverse modeling of highly defined soil column experiments and subsequent scenario modeling comparing different climate projections for a defined arid region. In arid regions, groundwater resources are prone to depletion due to excessive water use and little recharge potential. Especially in sand dune areas, groundwater recharge is highly dependent on vadose zone properties and corresponding water fluxes. Nevertheless, vadose zone water fluxes under arid conditions are hard to determine owing to, among other reasons, deepmore » vadose zones with generally low fluxes and only sporadic high infiltration events. In this study, we present an inverse model of infiltration experiments accounting for variable saturated nonisothermal water fluxes to estimate effective hydraulic and thermal parameters of dune sands. A subsequent scenario modeling links the results of the inverse model with projections of a global climate model until 2100. The scenario modeling clearly showed the high dependency of groundwater recharge on precipitation amounts and intensities, whereas temperature increases are only of minor importance for deep infiltration. However, simulated precipitation rates are still affected by high uncertainties in the response to the hydrological input data of the climate model. Thus, higher certainty in the prediction of precipitation pattern is a major future goal for climate modeling to constrain future groundwater management strategies in arid regions.« less

Design Fragments

DTIC Science & Technology

2007-04-19

define the patterns and are better at analyzing behavior. SPQR (System for Pattern Query and Recognition) [18, 58] can recognize pattern vari- ants...Stotts. SPQR : Flexible automated design pattern extraction from source code. ase, 00:215, 2003. ISSN 1527-1366. doi: http://doi.ieeecomputersociety. org

Preserved, deteriorated, and premorbidly impaired patterns of intellectual ability in schizophrenia.

PubMed

Ammari, Narmeen; Heinrichs, R Walter; Pinnock, Farena; Miles, Ashley A; Muharib, Eva; McDermid Vaz, Stephanie

2014-05-01

The main purpose of this investigation was to identify patterns of intellectual performance in schizophrenia patients suggesting preserved, deteriorated, and premorbidly impaired ability, and to determine clinical, cognitive, and functional correlates of these patterns. We assessed 101 patients with schizophrenia or schizoaffective disorder and 80 non-psychiatric control participants. The "preserved" performance pattern was defined by average-range estimated premorbid and current IQ with no evidence of decline (premorbid-current IQ difference <10 points). The "deteriorated" pattern was defined by a difference between estimated premorbid and current IQ estimates of 10 points or more. The premorbidly "impaired" pattern was defined by below average estimated premorbid and current IQ and no evidence of decline greater than 10 points. Preserved and deteriorated patterns in healthy controls were also identified and studied in comparison to patient findings. The groups were compared on demographic, neurocognitive, clinical and functionality variables. Patients with the preserved pattern outperformed those meeting criteria for deteriorated and compromised intellectual ability on a composite measure of neurocognitive ability as well as in terms of functional competence. Patients demonstrating the deteriorated and compromised patterns were equivalent across all measures. However, "preserved" patients failed to show any advantage in terms of community functioning and demonstrated cognitive impairments relative to control participants. Our results suggest that proposed patterns of intellectual decline and stability exist in both the schizophrenia and general populations, but may not hold true across other cognitive abilities and do not translate into differential functional outcome.

Hemodynamic signals of mixed messages during a social exchange.

PubMed

Zucker, Nancy L; Green, Steven; Morris, James P; Kragel, Philip; Pelphrey, Kevin A; Bulik, Cynthia M; LaBar, Kevin S

2011-06-22

This study used functional magnetic resonance imaging to characterize hemodynamic activation patterns recruited when the participants viewed mixed social communicative messages during a common interpersonal exchange. Mixed messages were defined as conflicting sequences of biological motion and facial affect signals that are unexpected within a particular social context (e.g. observing the reception of a gift). Across four social vignettes, valenced facial expressions were crossed with rejecting and accepting gestures in a virtual avatar responding to presentation of a gift from the participant. The results indicate that conflicting facial affect and gesture activated superior temporal sulcus, a region implicated in expectancy violations, as well as inferior frontal gyrus and putamen. Scenarios conveying rejection differentially activated the insula and putamen, regions implicated in embodied cognition, and motivated learning, as well as frontoparietal cortex. Characterizing how meaning is inferred from integration of conflicting nonverbal communicative cues is essential to understand nuances and complexities of human exchange.

Statistical density modification using local pattern matching

DOEpatents

Terwilliger, Thomas C.

2007-01-23

A computer implemented method modifies an experimental electron density map. A set of selected known experimental and model electron density maps is provided and standard templates of electron density are created from the selected experimental and model electron density maps by clustering and averaging values of electron density in a spherical region about each point in a grid that defines each selected known experimental and model electron density maps. Histograms are also created from the selected experimental and model electron density maps that relate the value of electron density at the center of each of the spherical regions to a correlation coefficient of a density surrounding each corresponding grid point in each one of the standard templates. The standard templates and the histograms are applied to grid points on the experimental electron density map to form new estimates of electron density at each grid point in the experimental electron density map.

Epigenetics, chromatin and genome organization: recent advances from the ENCODE project.

PubMed

Siggens, L; Ekwall, K

2014-09-01

The organization of the genome into functional units, such as enhancers and active or repressed promoters, is associated with distinct patterns of DNA and histone modifications. The Encyclopedia of DNA Elements (ENCODE) project has advanced our understanding of the principles of genome, epigenome and chromatin organization, identifying hundreds of thousands of potential regulatory regions and transcription factor binding sites. Part of the ENCODE consortium, GENCODE, has annotated the human genome with novel transcripts including new noncoding RNAs and pseudogenes, highlighting transcriptional complexity. Many disease variants identified in genome-wide association studies are located within putative enhancer regions defined by the ENCODE project. Understanding the principles of chromatin and epigenome organization will help to identify new disease mechanisms, biomarkers and drug targets, particularly as ongoing epigenome mapping projects generate data for primary human cell types that play important roles in disease. © 2014 The Association for the Publication of the Journal of Internal Medicine.

Feature-based attentional modulations in the absence of direct visual stimulation.

PubMed

Serences, John T; Boynton, Geoffrey M

2007-07-19

When faced with a crowded visual scene, observers must selectively attend to behaviorally relevant objects to avoid sensory overload. Often this selection process is guided by prior knowledge of a target-defining feature (e.g., the color red when looking for an apple), which enhances the firing rate of visual neurons that are selective for the attended feature. Here, we used functional magnetic resonance imaging and a pattern classification algorithm to predict the attentional state of human observers as they monitored a visual feature (one of two directions of motion). We find that feature-specific attention effects spread across the visual field-even to regions of the scene that do not contain a stimulus. This spread of feature-based attention to empty regions of space may facilitate the perception of behaviorally relevant stimuli by increasing sensitivity to attended features at all locations in the visual field.

Correlations between cerebral glucose metabolism and neuropsychological test performance in nonalcoholic cirrhotics.

PubMed

Lockwood, Alan H; Weissenborn, Karin; Bokemeyer, Martin; Tietge, U; Burchert, Wolfgang

2002-03-01

Many cirrhotics have abnormal neuropsychological test scores. To define the anatomical-physiological basis for encephalopathy in nonalcoholic cirrhotics, we performed resting-state fluorodeoxyglucose positron emission tomographic scans and administered a neuropsychological test battery to 18 patients and 10 controls. Statistical parametric mapping correlated changes in regional glucose metabolism with performance on the individual tests and a composite battery score. In patients without overt encephalopathy, poor performance correlated with reductions in metabolism in the anterior cingulate. In all patients, poor performance on the battery was positively correlated (p < 0.001) with glucose metabolism in bifrontal and biparietal regions of the cerebral cortex and negatively correlated with metabolism in hippocampal, lingual, and fusiform gyri and the posterior putamen. Similar patterns of abnormal metabolism were found when comparing the patients to 10 controls. Metabolic abnormalities in the anterior attention system and association cortices mediating executive and integrative function form the pathophysiological basis for mild hepatic encephalopathy.

Sequence stratigraphy of the Triassic in the Barentsz Sea

DOE Office of Scientific and Technical Information (OSTI.GOV)

Skjold, L.JU.; Van Veen, P.M.; Gjelberg, J.

1990-05-01

A regional study of the Triassic in the Barentsz Sea (20-32{degree}E, 71-74{degree}N) revealed sequences that correlate seismically for hundreds of kilometers. Recent offshore drilling results enabled them to establish a biostratigraphic time framework. Comparisons with information from onshore outcrops (such as the Svalbard Archipelago) aided the piecing together of these superregional sequences. Seismic character analysis identified three units with composite progradational patterns (Induan, Olenekian, and Anisian). Fluvial, deltaic, and marine deposits can be distinguished and located relative to the paleocoastlines. Corresponding downlap surfaces suggest the development of condensed intervals, predicted to consist of organic-rich source rocks, as was later confirmedmore » by drilling. Regional predictions based on this sequence-stratigraphic approach have proved valuable when correlating and evaluating well information. The sequences identified also help define third-order sea level curves for the area; these improve published curves thought to have global significance.« less

Normal injection of helium from swept struts into ducted supersonic flow

NASA Technical Reports Server (NTRS)

Mcclinton, C. R.; Torrence, M. G.

1975-01-01

Recent design studies have shown that airframe-integrated scramjets should include instream mounted, swept-back strut fuel injectors to obtain short combustors. Because there was no data in the literature on mixing characteristics of swept strut fuel injectors, the present investigation was undertaken to provide such data. This investigation was made with two swept struts in a closed duct at Mach number of 4.4 and nominal jet-to-air mass flow ratio of 0.029 with helium used to simulate hydrogen fuel. The data is compared with flat plate mounted normal injector data to obtain the effect of swept struts on mixing. Three injector patterns were evaluated representing the range of hole spacing and jet-to-freestream dynamic pressure ratio of interest. Measured helium concentration, pitot pressure, and static pressure in the downstream mixing region are used to generate contour plots necessary to define the mixing region flow field and the mixing parameters.

Rossby waves, extreme fronts, and wildfires in southeastern Australia

NASA Astrophysics Data System (ADS)

Reeder, Michael J.; Spengler, Thomas; Musgrave, Ruth

2015-03-01

The most catastrophic fires in recent history in southern Australia have been associated with extreme cold fronts. Here an extreme cold front is defined as one for which the maximum temperature at 2 m is at least 17°C lower on the day following the front. An anticyclone, which precedes the cold front, directs very dry northerlies or northwesterlies from the interior of the continent across the region. The passage of the cold front is followed by strong southerlies or southwesterlies. European Centre for Medium-Range Weather Forecasts ERA-Interim Reanalyses show that this regional synoptic pattern common to all strong cold fronts, and hence severe fire conditions, is a consequence of propagating Rossby waves, which grow to large amplitude and eventually irreversibly overturn. The process of overturning produces the low-level anticyclone and dry conditions over southern Australia, while simultaneously producing an upper level trough and often precipitation in northeastern Australia.

Functional imaging of conditioned aversive emotional responses in antisocial personality disorder.

PubMed

Schneider, F; Habel, U; Kessler, C; Posse, S; Grodd, W; Müller-Gärtner, H W

2000-01-01

Individuals with antisocial personality disorder (n = 12) and healthy controls (n = 12) were examined for cerebral regional activation involved in the processing of negative affect. A differential aversive classical conditioning paradigm was applied with odors as unconditioned stimuli and faces as conditioned stimuli. Functional magnetic resonance imaging (fMRI) based on echo-planar imaging was used while cerebral activity was studied during habituation, acquisition, and extinction. Individually defined cerebral regions were analyzed. Both groups indicated behavioral conditioning following subjective ratings of emotional valence to conditioned stimuli. Differential effects were found during acquisition in the amygdala and dorsolateral prefrontal cortex. Controls showed signal decreases, patients signal increases. These preliminary results revealed unexpected signal increases in cortical/subcortical areas of patients. The increases may result from an additional effort put in by these individuals to form negative emotional associations, a pattern of processing that may correspond to their characteristic deviant emotional behavior. Copyright 2000 S. Karger AG, Basel.

Regional Issue Identification and Assessment (RIIA). Volume III. Institutional barriers to developing power generation facilities in the Pacific Northwest

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morris, F. A.; Sawyer, C. H.; Maxwell, J. H.

1979-10-01

The Regional Assessments Division in the US Department of Energy (DOE) has undertaken a program to assess the probable consequences of various national energy policies in regions of the United States and to evaluate the constraints on national energy policy imposed by conditions in these regions. The program is referred to as the Regional Issues Identification and Assessment (RIIA) Program. Currently the RIIA Program is evaluating the Trendlong Mid-Mid scenario, a pattern of energy development for 1985 and 1990 derived from the Project Independence Evaluation System (PIES) model. This scenario assumes a medium annual growth rate in both the nationalmore » demand for and national supply of energy. It has been disaggregated to specify the generating capacity to be supplied by each energy source in each state. Pacific Northwest Laboratory (PNL) has the responsibility for evaluating the scenario for the Federal Region 10, consisting of Alaska, Idaho, Oregon, and Washington. PNL is identifying impacts and constraints associated with realizing the scenario in a variety of categories, including air and water quality impacts, health and safety effects, and socioeconomic impacts. This report summarizes the analysis of one such category: institutional constraints - defined to include legal, organizational, and political barriers to the achievement of the scenario in the Northwest.« less

Seasonal land-cover regions of the United States

USGS Publications Warehouse

Loveland, Thomas R.; Merchant, James W.; Brown, Jesslyn F.; Ohlen, Donald O.; Reed, Bradley C.; Olson, Paul; Hutchinson, John

1995-01-01

Global-change investigations have been hindered by deficiencies in the availability and quality of land-cover data. The U.S. Geological Survey and the University of Nebraska-Lincoln have collaborated on the development of a new approach to land-cover characterization that attempts to address requirements of the global-change research community and others interested in regional patterns of land cover. An experimental 1 -kilometer-resolution database of land-cover characteristics for the coterminous U.S. has been prepared to test and evaluate the approach. Using multidate Advanced Very High Resolution Radiometer (AVHRR) satellite data complemented by elevation, climate, ecoregions, and other digital spatial datasets, the authors define 152, seasonal land-cover regions. The regionalization is based on a taxonomy of areas with respect to data on land cover, seasonality or phenology, and relative levels of primary production. The resulting database consists of descriptions of the vegetation, land cover, and seasonal, spectral, and site characteristics for each region. These data are used in the construction of an illustrative 1:7,500,000-scaIe map of the seasonal land-cover regions as well as of smaller-scale maps portraying general land cover and seasonality. The seasonal land-cover characteristics database can also be tailored to provide a broad range of other landscape parameters useful in national and global-scale environmental modeling and assessment.

Tectonic patterns and regional stresses near Venusian coronae

NASA Astrophysics Data System (ADS)

Cyr, K. E.; Melosh, H. J.

1993-04-01

A stress analysis of tectonic patterns near Venusian coronae is reported. Combined local corona stresses and uniform regional stresses are used to predict patterns of surface tectonic features. The patterns are compared to those of coronae on Magellan images to determine the regional stress and elastic lithospheric thickness about the coronae. Regional stresses of 0.1-0.6 kbar and elastic lithospheric thicknesses of 10 +/- 5 km are estimated for three specific coronae.

Assessment of variations in taxonomic diversity, forest structure, and aboveground biomass using remote sensing along an altitudinal gradient in tropical montane forest of Costa Rica

NASA Astrophysics Data System (ADS)

Robinson, C. M.; Saatchi, S. S.; Clark, D.; Fricker, G. A.; Wolf, J.; Gillespie, T. W.; Rovzar, C. M.; Andelman, S.

2012-12-01

This research sought to understand how alpha and beta diversity of plants vary and relate to the three-dimensional vegetation structure and aboveground biomass along environmental gradients in the tropical montane forests of Braulio Carrillo National Park in Costa Rica. There is growing evidence that ecosystem structure plays an important role in defining patterns of species diversity and along with abiotic factors (climate and edaphic) control the phenotypic and functional variations across landscapes. It is well documented that strong subdivisions at local and regional scales are found mainly on geologic or climate gradients. These general determinants of biodiversity are best demonstrated in regions with natural gradients such as tropical montane forests. Altitudinal gradients provide a landscape scale changes through variations in topography, climate, and edaphic conditions on which we tested several theoretical and biological hypotheses regarding drivers of biodiversity. The study was performed by using forest inventory and botanical data from nine 1-ha plots ranging from 100 m to 2800 m above sea level and remote sensing data from airborne lidar and radar sensors to quantify variations in forest structure. In this study we report on the effectiveness of relating patterns of tree taxonomic alpha diversity to three-dimensional structure of a tropical montane forest using lidar and radar observations of forest structure and biomass. We assessed alpha and beta diversity at the species, genus, and family levels utilizing datasets provided by the Terrestrial Ecology Assessment and Monitoring (TEAM) Network. Through the comparison to active remote sensing imagery, our results show that there is a strong relationship between forest 3D-structure, and alpha and beta diversity controlled by variations in abiotic factors along the altitudinal gradient. Using spatial analysis with the aid of remote sensing data, we find distinct patterns along the environmental gradients defining species turnover and changes in functional diversity. The study will provide novel approaches to use detailed spatial information from remote sensing data to study relations between functional and taxonomic dimensions of diversity.

Simulation of speckle patterns with pre-defined correlation distributions.

PubMed

Song, Lipei; Zhou, Zhen; Wang, Xueyan; Zhao, Xing; Elson, Daniel S

2016-03-01

We put forward a method to easily generate a single or a sequence of fully developed speckle patterns with pre-defined correlation distribution by utilizing the principle of coherent imaging. The few-to-one mapping between the input correlation matrix and the correlation distribution between simulated speckle patterns is realized and there is a simple square relationship between the values of these two correlation coefficient sets. This method is demonstrated both theoretically and experimentally. The square relationship enables easy conversion from any desired correlation distribution. Since the input correlation distribution can be defined by a digital matrix or a gray-scale image acquired experimentally, this method provides a convenient way to simulate real speckle-related experiments and to evaluate data processing techniques.

Simulation of speckle patterns with pre-defined correlation distributions

PubMed Central

Song, Lipei; Zhou, Zhen; Wang, Xueyan; Zhao, Xing; Elson, Daniel S.

2016-01-01

We put forward a method to easily generate a single or a sequence of fully developed speckle patterns with pre-defined correlation distribution by utilizing the principle of coherent imaging. The few-to-one mapping between the input correlation matrix and the correlation distribution between simulated speckle patterns is realized and there is a simple square relationship between the values of these two correlation coefficient sets. This method is demonstrated both theoretically and experimentally. The square relationship enables easy conversion from any desired correlation distribution. Since the input correlation distribution can be defined by a digital matrix or a gray-scale image acquired experimentally, this method provides a convenient way to simulate real speckle-related experiments and to evaluate data processing techniques. PMID:27231589

The potential of audiomagnetotellurics in the study of geothermal fields: A case study from the northern segment of the La Candelaria Range, northwestern Argentina

NASA Astrophysics Data System (ADS)

Barcelona, Hernan; Favetto, Alicia; Peri, Veronica Gisel; Pomposiello, Cristina; Ungarelli, Carlo

2013-01-01

Despite its reduced penetration depth, audiomagnetotelluric (AMT) studies can be used to determine a broad range of features related to little studied geothermal fields. This technique requires a stepwise interpretation of results taking into consideration diverse information (e.g. topographic, hydrological, geological and/or structural data) to constrain the characteristics of the study area. In this work, an AMT study was performed at the hot springs in the northern segment of the La Candelaria Range in order to characterize the area at depth. Geometric aspects of the shallow subsurface were determined based on the dimensional and distortion analysis of the impedance tensors. Also, the correlation between structural features and regional strikes allowed us to define two geoelectric domains, useful to determine the controls on fluid circulation. The subsurface resistivity distribution was determined through 1D and 2D models. The patterns of the 1D models were compared with the morpho-structure of the range. Shallow and deep conductive zones were defined and a possible shallow geothermal system scheme proposed. A strong correlation was found between the AMT results and the geological framework of the region, showing the relevance of using AMT in geothermal areas during the early stages of subsurface prospecting.

Mutations Affecting Expression of the rosy Locus in Drosophila melanogaster

PubMed Central

Lee, Chong Sung; Curtis, Daniel; McCarron, Margaret; Love, Carol; Gray, Mark; Bender, Welcome; Chovnick, Arthur

1987-01-01

The rosy locus in Drosophila melanogaster codes for the enzyme xanthine dehydrogenase (XDH). Previous studies defined a "control element" near the 5' end of the gene, where variant sites affected the amount of rosy mRNA and protein produced. We have determined the DNA sequence of this region from both genomic and cDNA clones, and from the ry+10 underproducer strain. This variant strain had many sequence differences, so that the site of the regulatory change could not be fixed. A mutagenesis was also undertaken to isolate new regulatory mutations. We induced 376 new mutations with 1-ethyl-1-nitrosourea (ENU) and screened them to isolate those that reduced the amount of XDH protein produced, but did not change the properties of the enzyme. Genetic mapping was used to find mutations located near the 5' end of the gene. DNA from each of seven mutants was cloned and sequenced through the 5' region. Mutant base changes were identified in all seven; they appear to affect splicing and translation of the rosy mRNA. In a related study (T. P. Keith et al. 1987), the genomic and cDNA sequences are extended through the 3' end of the gene; the combined sequences define the processing pattern of the rosy transcript and predict the amino acid sequence of XDH. PMID:3036645

Do Online Learning Patterns Exhibit Regional and Demographic Differences?

ERIC Educational Resources Information Center

Hsieh, Tsui-Chuan; Yang, Chyan

2012-01-01

This paper used a multi-level latent class model to evaluate whether online learning patterns exhibit regional differences and demographics. This study discovered that the Internet learning pattern consists of five segments, and the region of Taiwan is divided into two segments and further found that both the user and the regional segments are…

Healthy eating patterns associated with acculturation, sex and BMI among Mexican Americans.

PubMed

Reininger, Belinda; Lee, MinJae; Jennings, Rose; Evans, Alexandra; Vidoni, Michelle

2017-05-01

Examine relationships of healthy and unhealthy dietary patterns with BMI, sex, age and acculturation among Mexican Americans. Cross-sectional. Participants completed culturally tailored Healthy and Unhealthy Eating Indices. Multivariable mixed-effect Poisson regression models compared food pattern index scores and dietary intake of specific foods by BMI, sex, age and acculturation defined by language preference and generational status. Participants recruited from the Cameron County Hispanic Cohort study, Texas-Mexico border region, between 2008 and 2011. Mexican-American males and females aged 18-97 years (n 1250). Participants were primarily female (55·3 %), overweight or obese (85·7 %), preferred Spanish language (68·0 %) and first-generation status (60·3 %). Among first-generation participants, bilingual participants were less likely to have a healthy eating pattern than preferred Spanish-speaking participants (rate ratio (RR)=0·79, P=0·0218). This association was also found in males (RR=0·81, P=0·0098). Preferred English-speaking females were less likely to consume healthy foods than preferred Spanish-speaking females (RR=0·84, P=0·0293). Among second-generation participants, preferred English-speaking participants were more likely to report a higher unhealthy eating pattern than preferred Spanish-speaking participants (RR=1·23, P=0·0114). Higher unhealthy eating patterns were also found in females who preferred English v. females who preferred Spanish (RR=1·23, P=0·0107) or were bilingual (RR=1·26, P=0·0159). Younger, male participants were more likely to have a higher unhealthy eating pattern. BMI and diabetes status were not significantly associated with healthy or unhealthy eating patterns. Acculturation, age, sex and education are associated with healthy and unhealthy dietary patterns. Nutrition interventions for Mexican Americans should tailor approaches by these characteristics.

Spatiotemporal patterns in reaction-diffusion system and in a vibrated granular bed

DOE Office of Scientific and Technical Information (OSTI.GOV)

Swinney, H.L.; Lee, K.J.; McCormick, W.D.

Experiments on a quasi-two-dimensional reaction-diffusion system reveal transitions from a uniform state to stationary hexagonal, striped, and rhombic spatial patterns. For other reactor conditions lamellae and self-replicating spot patterns are observed. These patterns form in continuously fed thin gel reactors that can be maintained indefinitely in well-defined nonequilibrium states. Reaction-diffusion models with two chemical species yield patterns similar to those observed in the experiments. Pattern formation is also being examined in vertically oscillated thin granular layers (typically 3-30 particle diameters deep). For small acceleration amplitudes, a granular layer is flat, but above a well-defined critical acceleration amplitude, spatial patterns spontaneouslymore » form. Disordered time-dependent granular patterns are observed as well as regular patterns of squares, stripes, and hexagons. A one-dimensional model consisting of a completely inelastic ball colliding with a sinusoidally oscillating platform provides a semi-quantitative description of most of the observed bifurcations between the different spatiotemporal regimes.« less

New approach for producing chemical templates over large area by Molecular Transfer Printing

NASA Astrophysics Data System (ADS)

Inoue, Takejiro; Janes, Dustin; Ren, Jiaxing; Willson, Grant; Ellison, Christopher; Nealey, Paul

2014-03-01

Fabrication of well-defined chemically patterned surfaces is crucially important to the development of next generation microprocessors, hard disk memory devices, photonic/plasmonic devices, separation membranes, and biological microarrays. One promising patterning method in these fields is Molecular Transfer Printing (MTP), which replicates chemical patterns with feature dimensions of the order of 10nm utilizing a master template defined by the microphase separated domains of a block copolymer thin film. The total transfer printing area achievable by MTP has so far been limited by the contact area between two rigid substrates. Therefore, strategies to make conformal contact between substrates could be practically useful because a single lithographically-defined starting pattern could be used to fabricate many replicates by a low-cost process. Here we show a new approach that utilizes a chemically deposited SiN layer and a liquid conformal layer to enable transfer printing of chemical patterns upon thermal annealing over large, continuous areas. We anticipate that our process could be integrated into Step and Flash Imprint Lithography (SFIL) tools to achieve conformal layer thicknesses thin and uniform enough to permit pattern transfer through a dry-etch protocol.

Distribution patterns in the native vascular flora of Iceland.

PubMed

Wasowicz, Pawel; Pasierbiński, Andrzej; Przedpelska-Wasowicz, Ewa Maria; Kristinsson, Hörður

2014-01-01

The aim of our study was to reveal biogeographical patterns in the native vascular flora of Iceland and to define ecological factors responsible for these patterns. We analysed dataset of more than 500,000 records containing information on the occurrence of vascular plants. Analysis of ecological factors included climatic (derived from WORLDCLIM data), topographic (calculated from digital elevation model) and geological (bedrock characteristics) variables. Spherical k-means clustering and principal component analysis were used to detect biogeographical patterns and to study the factors responsible for them. We defined 10 biotic elements exhibiting different biogeographical patterns. We showed that climatic (temperature-related) and topographic variables were the most important factors contributing to the spatial patterns within the Icelandic vascular flora and that these patterns are almost completely independent of edaphic factors (bedrock type). Our study is the first one to analyse the biogeographical differentiation of the native vascular flora of Iceland.

Neural correlates of processing facial identity based on features versus their spacing.

PubMed

Maurer, D; O'Craven, K M; Le Grand, R; Mondloch, C J; Springer, M V; Lewis, T L; Grady, C L

2007-04-08

Adults' expertise in recognizing facial identity involves encoding subtle differences among faces in the shape of individual facial features (featural processing) and in the spacing among features (a type of configural processing called sensitivity to second-order relations). We used fMRI to investigate the neural mechanisms that differentiate these two types of processing. Participants made same/different judgments about pairs of faces that differed only in the shape of the eyes and mouth, with minimal differences in spacing (featural blocks), or pairs of faces that had identical features but differed in the positions of those features (spacing blocks). From a localizer scan with faces, objects, and houses, we identified regions with comparatively more activity for faces, including the fusiform face area (FFA) in the right fusiform gyrus, other extrastriate regions, and prefrontal cortices. Contrasts between the featural and spacing conditions revealed distributed patterns of activity differentiating the two conditions. A region of the right fusiform gyrus (near but not overlapping the localized FFA) showed greater activity during the spacing task, along with multiple areas of right frontal cortex, whereas left prefrontal activity increased for featural processing. These patterns of activity were not related to differences in performance between the two tasks. The results indicate that the processing of facial features is distinct from the processing of second-order relations in faces, and that these functions are mediated by separate and lateralized networks involving the right fusiform gyrus, although the FFA as defined from a localizer scan is not differentially involved.

Sonic hedgehog: restricted expression and limb dysmorphologies

PubMed Central

Hill, Robert E; Heaney, Simon JH; Lettice, Laura A

2003-01-01

Sonic hedgehog, SHH, is required for patterning the limb. The array of skeletal elements that compose the hands and feet, and the ordered arrangement of these bones to form the pattern of fingers and toes are dependent on SHH. The mechanism of action of SHH in the limb is not fully understood; however, an aspect that appears to be important is the localized, asymmetric expression of Shh. Shh is expressed in the posterior margin of the limb bud in a region defined as the zone of polarizing activity (ZPA). Analysis of mouse mutants which have polydactyly (extra toes) shows that asymmetric expression of Shh is lost due to the appearance of an ectopic domain of expression in the anterior limb margin. One such polydactylous mouse mutant, sasquatch (Ssq), maps to the corresponding chromosomal region of the human condition pre-axial polydactyly (PPD) and thus represents a model for this condition. The mutation responsible for Ssq is located 1 Mb away from the Shh gene; however, the mutation disrupts a long-range cis-acting regulator of Shh expression. By inference, human pre-axial polydactyly results from a similar disruption of Shh expression. Other human congenital abnormalities also map near the pre-axial polydactyly locus, suggesting a major chromosomal region for limb dysmorphologies. The distinct phenotypes range from loss of all bones of the hands and feet to syndactyly of the soft tissue and fusion of the digits. We discuss the role played by Shh expression in mouse mutant phenotypes and the human limb dysmorphologies. PMID:12587915

Seasonal and spatial patterns of erosivity in a tropical watershed of the Colombian Andes

NASA Astrophysics Data System (ADS)

Hoyos, Natalia; Waylen, Peter R.; Jaramillo, Álvaro

2005-11-01

The Dosquebradas Basin, in the central coffee growing region of Colombia, covers an area of 58 km 2 between 1350 and 2150 m of elevation, with an annual precipitation of 2600-3200 mm. Seasonal erosivity (EI30), as defined by the Revised Universal Soil Loss Equation (RUSLE), was calculated for 11 years of record (1987-1997) from six pluviographic stations located within 21 km of the basin. Regression models for each station indicated that storm rainfall explained 61-70% of the variation in storm erosivity. Individual storms represented as much as 25% of the annual EI30 (10,409-15,975 MJ mm ha -1 h -1 yr -1). At the seasonal scale, the explained variation increased to 75-86%. There was a significant difference between wet and dry seasons, with higher values and larger increases in erosivity per unit increase in rainfall during the wet seasons. Two pooled regression models, one for the wet and one for the dry seasons, were created and used to estimate seasonal erosivity for 10 stations with pluviometric data. Interpolation surfaces were created from seasonal values using the local polynomial algorithm. Spatial patterns of erosivity were related to (a) the regional elevation gradient, particularly important during the dry seasons, and (b) local topographic effects, particularly during the wet seasons. Our findings underscore the importance of using seasonal erosivity values and local rainfall intensity records in tropical mountainous regions characterized by marked rainfall seasonality and complex topography.

Temporal Asthma Patterns Using Repeated Questionnaires over 13 Years in a Large French Cohort of Women

PubMed Central

Sanchez, Margaux; Bousquet, Jean; Le Moual, Nicole; Jacquemin, Bénédicte; Clavel-Chapelon, Françoise; Humbert, Marc; Kauffmann, Francine; Tubert-Bitter, Pascale; Varraso, Raphaëlle

2013-01-01

Variable expression is one aspect of the heterogeneity of asthma. We aimed to define a variable pattern, which is relevant in general health epidemiological cohorts. Our objectives were to assess whether: 1) asthma patterns defined using simple asthma questions through repeated measurements could reflect disease variability 2) these patterns may further be classified according to asthma severity/control. Among 70,428 French women, we used seven questionnaires (1992–2005) and a comprehensive reimbursement database (2004–2009) to define three reliable asthma patterns based on repeated positive answers to the ever asthma attack question: “never asthma” (n = 64,061); “inconsistent” (“yes” followed by “no”, n = 3,514); “consistent” (fully consistent positive answers, n = 2,853). The “Inconsistent” pattern was related to both long-term (childhood-onset asthma with remission in adulthood) and short-term (reported asthma attack in the last 12 months, associated with asthma medication) asthma variability, showing that repeated questions are relevant markers of the variable expression of asthma. Furthermore, in this pattern, the number of positive responses (1992–2005) predicted asthma drug consumption in subsequent years, a marker of disease severity. The “Inconsistent” pattern is a phenotype that may capture the variable expression of asthma. Repeated answers, even to a simple question, are too often neglected. PMID:23741466

9 CFR 98.38 - Restrictions on the importation of swine semen from the APHIS-defined EU CSF region.

Code of Federal Regulations, 2010 CFR

2010-01-01

... swine semen from the APHIS-defined EU CSF region. 98.38 Section 98.38 Animals and Animal Products ANIMAL... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMAL EMBRYOS AND ANIMAL SEMEN Certain Animal Semen § 98.38 Restrictions on the importation of swine semen from the APHIS-defined EU CSF region. In...

9 CFR 98.38 - Restrictions on the importation of swine semen from the APHIS-defined European CSF region.

Code of Federal Regulations, 2012 CFR

2012-01-01

... swine semen from the APHIS-defined European CSF region. 98.38 Section 98.38 Animals and Animal Products... Certain Animal Semen § 98.38 Restrictions on the importation of swine semen from the APHIS-defined European CSF region. In addition to meeting all other applicable provisions of this part, swine semen...

9 CFR 98.38 - Restrictions on the importation of swine semen from the APHIS-defined European CSF region.

Code of Federal Regulations, 2013 CFR

2013-01-01

... swine semen from the APHIS-defined European CSF region. 98.38 Section 98.38 Animals and Animal Products... Certain Animal Semen § 98.38 Restrictions on the importation of swine semen from the APHIS-defined European CSF region. In addition to meeting all other applicable provisions of this part, swine semen...

9 CFR 98.38 - Restrictions on the importation of swine semen from the APHIS-defined European CSF region.

Code of Federal Regulations, 2014 CFR

2014-01-01

... swine semen from the APHIS-defined European CSF region. 98.38 Section 98.38 Animals and Animal Products... Certain Animal Semen § 98.38 Restrictions on the importation of swine semen from the APHIS-defined European CSF region. In addition to meeting all other applicable provisions of this part, swine semen...

New whole-body sensory-motor gradients revealed using phase-locked analysis and verified using multivoxel pattern analysis and functional connectivity.

PubMed

Zeharia, Noa; Hertz, Uri; Flash, Tamar; Amedi, Amir

2015-02-18

Topographic organization is one of the main principles of organization in the human brain. Specifically, whole-brain topographic mapping using spectral analysis is responsible for one of the greatest advances in vision research. Thus, it is intriguing that although topography is a key feature also in the motor system, whole-body somatosensory-motor mapping using spectral analysis has not been conducted in humans outside M1/SMA. Here, using this method, we were able to map a homunculus in the globus pallidus, a key target area for deep brain stimulation, which has not been mapped noninvasively or in healthy subjects. The analysis clarifies contradictory and partial results regarding somatotopy in the caudal-cingulate zone and rostral-cingulate zone in the medial wall and in the putamen. Most of the results were confirmed at the single-subject level and were found to be compatible with results from animal studies. Using multivoxel pattern analysis, we could predict movements of individual body parts in these homunculi, thus confirming that they contain somatotopic information. Using functional connectivity, we demonstrate interhemispheric functional somatotopic connectivity of these homunculi, such that the somatotopy in one hemisphere could have been found given the connectivity pattern of the corresponding regions of interest in the other hemisphere. When inspecting the somatotopic and nonsomatotopic connectivity patterns, a similarity index indicated that the pattern of connected and nonconnected regions of interest across different homunculi is similar for different body parts and hemispheres. The results show that topographical gradients are even more widespread than previously assumed in the somatosensory-motor system. Spectral analysis can thus potentially serve as a gold standard for defining somatosensory-motor system areas for basic research and clinical applications. Copyright © 2015 the authors 0270-6474/15/352845-15$15.00/0.

Animal perception of seasonal thresholds: changes in elephant movement in relation to rainfall patterns.

PubMed

Birkett, Patricia J; Vanak, Abi T; Muggeo, Vito M R; Ferreira, Salamon M; Slotow, Rob

2012-01-01

The identification of temporal thresholds or shifts in animal movement informs ecologists of changes in an animal's behaviour, which contributes to an understanding of species' responses in different environments. In African savannas, rainfall, temperature and primary productivity influence the movements of large herbivores and drive changes at different scales. Here, we developed a novel approach to define seasonal shifts in movement behaviour by examining the movements of a highly mobile herbivore (elephant; Loxodonta africana), in relation to local and regional rainfall patterns. We used speed to determine movement changes of between 8 and 14 GPS-collared elephant cows, grouped into five spatial clusters, in Kruger National Park, South Africa. To detect broad-scale patterns of movement, we ran a three-year daily time-series model for each individual (2007-2009). Piecewise regression models provided the best fit for elephant movement, which exhibited a segmented, waveform pattern over time. Major breakpoints in speed occurred at the end of the dry and wet seasons of each year. During the dry season, female elephant are constrained by limited forage and thus the distances they cover are shorter and less variable. Despite the inter-annual variability of rainfall, speed breakpoints were strongly correlated with both local and regional rainfall breakpoints across all three years. Thus, at a multi-year scale, rainfall patterns significantly affect the movements of elephant. The variability of both speed and rainfall breakpoints across different years highlights the need for an objective definition of seasonal boundaries. By using objective criteria to determine behavioural shifts, we identified a biologically meaningful indicator of major changes in animal behaviour in different years. We recommend the use of such criteria, from an animal's perspective, for delineating seasons or other extrinsic shifts in ecological studies, rather than arbitrarily fixed definitions based on convention or common practice.

Effects of early afterdepolarizations on excitation patterns in an accurate model of the human ventricles

PubMed Central

Seemann, Gunnar; Panfilov, Alexander V.; Vandersickel, Nele

2017-01-01

Early Afterdepolarizations, EADs, are defined as the reversal of the action potential before completion of the repolarization phase, which can result in ectopic beats. However, the series of mechanisms of EADs leading to these ectopic beats and related cardiac arrhythmias are not well understood. Therefore, we aimed to investigate the influence of this single cell behavior on the whole heart level. For this study we used a modified version of the Ten Tusscher-Panfilov model of human ventricular cells (TP06) which we implemented in a 3D ventricle model including realistic fiber orientations. To increase the likelihood of EAD formation at the single cell level, we reduced the repolarization reserve (RR) by reducing the rapid delayed rectifier Potassium current and raising the L-type Calcium current. Varying these parameters defined a 2D parametric space where different excitation patterns could be classified. Depending on the initial conditions, by either exciting the ventricles with a spiral formation or burst pacing protocol, we found multiple different spatio-temporal excitation patterns. The spiral formation protocol resulted in the categorization of a stable spiral (S), a meandering spiral (MS), a spiral break-up regime (SB), spiral fibrillation type B (B), spiral fibrillation type A (A) and an oscillatory excitation type (O). The last three patterns are a 3D generalization of previously found patterns in 2D. First, the spiral fibrillation type B showed waves determined by a chaotic bi-excitable regime, i.e. mediated by both Sodium and Calcium waves at the same time and in same tissue settings. In the parameter region governed by the B pattern, single cells were able to repolarize completely and different (spiral) waves chaotically burst into each other without finishing a 360 degree rotation. Second, spiral fibrillation type A patterns consisted of multiple small rotating spirals. Single cells failed to repolarize to the resting membrane potential hence prohibiting the Sodium channel gates to recover. Accordingly, we found that Calcium waves mediated these patterns. Third, a further reduction of the RR resulted in a more exotic parameter regime whereby the individual cells behaved independently as oscillators. The patterns arose due to a phase-shift of different oscillators as disconnection of the cells resulted in continuation of the patterns. For all patterns, we computed realistic 9 lead ECGs by including a torso model. The B and A type pattern exposed the behavior of Ventricular Tachycardia (VT). We conclude that EADs at the single cell level can result in different types of cardiac fibrillation at the tissue and 3D ventricle level. PMID:29216239

Glacier dynamics of the Pamir-Karakoram-Himalaya region over the last 40 years

NASA Astrophysics Data System (ADS)

Gourmelen, N.; Dehecq, A.; Trouvé, E.

2014-12-01

Climate warming over the 20th century has caused drastic changes in mountain glaciers globally, and of the Himalayan glaciers in particular. The stakes are high; glaciers and ice caps are the largest contributor to the increase in the mass of the world's oceans, and the Himalayas play a key role in the hydrology of the region, impacting on the economy, food safety and flood risk. Partial monitoring of the Himalayan glaciers has revealed a mixed picture; while many of the Himalayan glaciers are retreating, in some cases locally stable or advancing glaciers in this region have also been observed. But recent controversies have highlighted the need to understand the glaciers dynamic and its relationship with climate change in the region. Earth Observation provides a mean for global and long-term monitoring of mountain glaciers' dynamics. In the frame of the Dragon program, a partnership between the European Space Agency (ESA) and the Chinese Center for Earth Observation (NRSCC), we begun a monitoring program aimed at quantifying multidecadal changes in glaciers' flow at the scale of the entire Himalayas and Karakoram from a 40 years' archive of Earth Observation. Ultimately, the provision of a global and time-sensitive glaciers velocity product will help to understand the evolution of the Himalayan glaciers in lights of glaciological (e.g. presence of debris-cover, surges, proglacial lakes) and climatic conditions. Here we present a region-wide analysis of annual and seasonnal glacier flow velocity covering the Pamir-Karakoram-Himalaya region obtained from the analysis of the entire archive of Landsat data. Over 90% of the ice-covered regions, as defined by the Randolph Glacier Inventory, are measured, with precision on the retrieved velocity of the order of 2 m/yr. We show that the first order temporal evolution of glacier flow mirrors the pattern of glacier mass balance. We observe a general decrease of ice velocity in regions of known ice mass loss, and a more complex patterns consisting of mixed acceleration and decrease of ice velocity in regions that are known to be affected by stable mass balance and surge-like behavior.

PATTERNS OF TREE DOMINANCE IN CONIFEROUS RIPARIAN FORESTS

EPA Science Inventory

This research quantified patterns of riparian tree dominance in western Oregon, USA and then compared the observed patterns with the expected patterns defined from the literature. Research was conducted at 110 riparian sites located on private and public lands. The field sites we...

1H-MRSI pattern perturbation in a mouse glioma: the effects of acute hyperglycemia and moderate hypothermia.

PubMed

Simões, R V; Delgado-Goñi, T; Lope-Piedrafita, S; Arús, C

2010-01-01

MR spectroscopic Imaging (MRSI), with PRESS localization, is used here to monitor the effects of acute hyperglycemia in the spectral pattern of 11 mice bearing GL261 gliomas at normothermia (36.5-37.5 degrees C) and at hypothermia (28.5-29.5 degrees C). These in vivo studies were complemented by ex vivo high resolution magic angle spinning (HR-MAS) analysis of GL261 tumor samples from 6 animals sacrificed by focused microwave irradiation, and blood glucose measurements in 12 control mice. Apparent glucose levels, monitored by in vivo MRSI in brain tumors during acute hyperglycemia, rose to an average of 1.6-fold during hypothermia (p < 0.05), while no significant changes were detected at normothermia, or in control experiments performed at euglycemia, or in normal/peritumoral brain regions. Ex vivo analysis of glioma-bearing mouse brains at hypothermia revealed higher glucose increases in distinct regions during the acute hyperglycemic challenge (up to 6.6-fold at the tumor center), in agreement with maximal in vivo blood glucose changes (5-fold). Phantom studies on taurine plus glucose containing solutions explained the differences between in vivo and ex vivo measurements. Our results also indicate brain tumor heterogeneity in the four animal tumors investigated in response to a defined metabolic challenge.

Modulatory compartments in cortex and local regulation of cholinergic tone.

PubMed

Coppola, Jennifer J; Ward, Nicholas J; Jadi, Monika P; Disney, Anita A

2016-09-01

Neuromodulatory signaling is generally considered broad in its impact across cortex. However, variations in the characteristics of cortical circuits may introduce regionally-specific responses to diffuse modulatory signals. Features such as patterns of axonal innervation, tissue tortuosity and molecular diffusion, effectiveness of degradation pathways, subcellular receptor localization, and patterns of receptor expression can lead to local modification of modulatory inputs. We propose that modulatory compartments exist in cortex and can be defined by variation in structural features of local circuits. Further, we argue that these compartments are responsible for local regulation of neuromodulatory tone. For the cholinergic system, these modulatory compartments are regions of cortical tissue within which signaling conditions for acetylcholine are relatively uniform, but between which signaling can vary profoundly. In the visual system, evidence for the existence of compartments indicates that cholinergic modulation likely differs across the visual pathway. We argue that the existence of these compartments calls for thinking about cholinergic modulation in terms of finer-grained control of local cortical circuits than is implied by the traditional view of this system as a diffuse modulator. Further, an understanding of modulatory compartments provides an opportunity to better understand and perhaps correct signal modifications that lead to pathological states. Copyright © 2016 Elsevier Ltd. All rights reserved.

Investigation of relationships between linears, total and hazy areas, and petroleum production in the Williston Basin: An ERTS approach

NASA Technical Reports Server (NTRS)

Erickson, J. M.; Street, J. S. (Principal Investigator); Munsell, C. J.; Obrien, D. E.

1975-01-01

The author has identified the following significant results. ERTS-1 imagery in a variety of formats was used to locate linear, tonal, and hazy features and to relate them to areas of hydrocarbon production in the Williston Basin of North Dakota, eastern Montana, and northern South Dakota. Derivative maps of rectilinear, curvilinear, tonal, and hazy features were made using standard laboratory techniques. Mapping of rectilinears on both bands 5 and 7 over the entire region indicated the presence of a northeast-southwest and a northwest-southeast regional trend which is indicative of the bedrock fracture pattern in the basin. Curved lines generally bound areas of unique tone, maps of tonal patterns repeat many of the boundaries seen on curvilinear maps. Tones were best analyzed on spring and fall imagery in the Williston Basin. It is postulated that hazy areas are caused by atmospheric phenomena. The ability to use ERTS imagery as an exploration tool was examined where petroleum and gas are presently produced (Bottineau Field, Nesson and Antelope anticlines, Redwing Creek, and Cedar Creek anticline). It is determined that some tonal and linear features coincide with location of present production in Redwing and Cedar Creeks. In the remaining cases, targets could not be sufficiently well defined to justify this method.

Acoustofluidic waveguides for localized control of acoustic wavefront in microfluidics

PubMed Central

Bian, Yusheng; Guo, Feng; Yang, Shujie; Mao, Zhangming; Bachman, Hunter; Tang, Shi-Yang; Ren, Liqiang; Zhang, Bin; Gong, Jianying; Guo, Xiasheng

2017-01-01

The precise manipulation of acoustic fields in microfluidics is of critical importance for the realization of many biomedical applications. Despite the tremendous efforts devoted to the field of acoustofluidics during recent years, dexterous control, with an arbitrary and complex acoustic wavefront, in a prescribed, microscale region is still out of reach. Here, we introduce the concept of acoustofluidic waveguide, a three-dimensional compact configuration that is capable of locally guiding acoustic waves into a fluidic environment. Through comprehensive numerical simulations, we revealed the possibility of forming complex field patterns with defined pressure nodes within a highly localized, pre-determined region inside the microfluidic chamber. We also demonstrated the tunability of the acoustic field profile through controlling the size and shape of the waveguide geometry, as well as the operational frequency of the acoustic wave. The feasibility of the waveguide concept was experimentally verified via microparticle trapping and patterning. Our acoustofluidic waveguiding structures can be readily integrated with other microfluidic configurations and can be further designed into more complex types of passive acoustofluidic devices. The waveguide platform provides a promising alternative to current acoustic manipulation techniques and is useful in many applications such as single-cell analysis, point-of-care diagnostics, and studies of cell–cell interactions. PMID:29358901

Country-specific dietary patterns and associations with socioeconomic status in European children: the IDEFICS study.

PubMed

Fernández-Alvira, J M; Bammann, K; Pala, V; Krogh, V; Barba, G; Eiben, G; Hebestreit, A; Veidebaum, T; Reisch, L; Tornaritis, M; Kovacs, E; Huybrechts, I; Moreno, L A

2014-07-01

Children from lower socioeconomic status (SES) may be at higher risk of unhealthy eating. We described country-specific dietary patterns among children aged 2-9 years from eight European countries participating in the IDEFICS study and assessed the association of dietary patterns with an additive SES indicator. Children aged 2-9 years from eight European countries were recruited in 2007-2008. Principal component analysis was applied to identify dietary country-specific patterns. Linear regression analyses were applied to assess their association with SES. Two to four dietary patterns were identified in the participating regions. The existence of a 'processed' pattern was found in the eight regions. Also, a 'healthy' pattern was identified in seven of the eight regions. In addition, region-specific patterns were identified, reflecting the existing gastronomic and cultural differences in Europe. The 'processed' pattern was significantly inversely associated with the SES additive indicator in all countries except Sweden, whereas the 'healthy' pattern was positively associated with SES in the Belgian, Estonian, German and Hungarian regions, but was not significant in the Italian, Spanish and Swedish regions. A 'processed' pattern and a 'healthy' pattern were found in most of the participating countries in the IDEFICS study, with comparable food item profiles. The results showed a strong inverse association of SES with the 'processed' pattern, suggesting that children of parents with lower SES may be at higher risk of unhealthy eating. Therefore, special focus should be given to parents and their children from lower SES levels when developing healthy eating promotion strategies.

Three-Dimensional Gene Map of Cancer Cell Types: Structural Entropy Minimisation Principle for Defining Tumour Subtypes

PubMed Central

Li, Angsheng; Yin, Xianchen; Pan, Yicheng

2016-01-01

In this study, we propose a method for constructing cell sample networks from gene expression profiles, and a structural entropy minimisation principle for detecting natural structure of networks and for identifying cancer cell subtypes. Our method establishes a three-dimensional gene map of cancer cell types and subtypes. The identified subtypes are defined by a unique gene expression pattern, and a three-dimensional gene map is established by defining the unique gene expression pattern for each identified subtype for cancers, including acute leukaemia, lymphoma, multi-tissue, lung cancer and healthy tissue. Our three-dimensional gene map demonstrates that a true tumour type may be divided into subtypes, each defined by a unique gene expression pattern. Clinical data analyses demonstrate that most cell samples of an identified subtype share similar survival times, survival indicators and International Prognostic Index (IPI) scores and indicate that distinct subtypes identified by our algorithms exhibit different overall survival times, survival ratios and IPI scores. Our three-dimensional gene map establishes a high-definition, one-to-one map between the biologically and medically meaningful tumour subtypes and the gene expression patterns, and identifies remarkable cells that form singleton submodules. PMID:26842724

Iterative Strategies for Aftershock Classification in Automatic Seismic Processing Pipelines

NASA Astrophysics Data System (ADS)

Gibbons, Steven J.; Kværna, Tormod; Harris, David B.; Dodge, Douglas A.

2016-04-01

Aftershock sequences following very large earthquakes present enormous challenges to near-realtime generation of seismic bulletins. The increase in analyst resources needed to relocate an inflated number of events is compounded by failures of phase association algorithms and a significant deterioration in the quality of underlying fully automatic event bulletins. Current processing pipelines were designed a generation ago and, due to computational limitations of the time, are usually limited to single passes over the raw data. With current processing capability, multiple passes over the data are feasible. Processing the raw data at each station currently generates parametric data streams which are then scanned by a phase association algorithm to form event hypotheses. We consider the scenario where a large earthquake has occurred and propose to define a region of likely aftershock activity in which events are detected and accurately located using a separate specially targeted semi-automatic process. This effort may focus on so-called pattern detectors, but here we demonstrate a more general grid search algorithm which may cover wider source regions without requiring waveform similarity. Given many well-located aftershocks within our source region, we may remove all associated phases from the original detection lists prior to a new iteration of the phase association algorithm. We provide a proof-of-concept example for the 2015 Gorkha sequence, Nepal, recorded on seismic arrays of the International Monitoring System. Even with very conservative conditions for defining event hypotheses within the aftershock source region, we can automatically remove over half of the original detections which could have been generated by Nepal earthquakes and reduce the likelihood of false associations and spurious event hypotheses. Further reductions in the number of detections in the parametric data streams are likely using correlation and subspace detectors and/or empirical matched field processing.

Ictal connectivity in childhood absence epilepsy: Associations with outcome.

PubMed

Tenney, Jeffrey R; Kadis, Darren S; Agler, William; Rozhkov, Leonid; Altaye, Mekibib; Xiang, Jing; Vannest, Jennifer; Glauser, Tracy A

2018-05-01

The understanding of childhood absence epilepsy (CAE) has been revolutionized over the past decade, but the biological mechanisms responsible for variable treatment outcomes are unknown. Our purpose in this prospective observational study was to determine how pretreatment ictal network pathways, defined using a combined electroencephalography (EEG)-functional magnetic resonance imaging (EEG-fMRI) and magnetoencephalography (MEG) effective connectivity analysis, were related to treatment response. Sixteen children with newly diagnosed and drug-naive CAE had 31 typical absence seizures during EEG-fMRI and 74 during MEG. The spatial extent of the pretreatment ictal network was defined using fMRI hemodynamic response with an event-related independent component analysis (eICA). This spatially defined pretreatment ictal network supplied prior information for MEG-effective connectivity analysis calculated using phase slope index (PSI). Treatment outcome was assessed 2 years following diagnosis and dichotomized to ethosuximide (ETX)-treatment responders (N = 11) or nonresponders (N = 5). Effective connectivity of the pretreatment ictal network was compared to the treatment response. Patterns of pretreatment connectivity demonstrated strongest connections in the thalamus and posterior brain regions (parietal, posterior cingulate, angular gyrus, precuneus, and occipital) at delta frequencies and the frontal cortices at gamma frequencies (P < .05). ETX treatment nonresponders had pretreatment connectivity, which was decreased in the precuneus region and increased in the frontal cortex compared to ETX responders (P < .05). Pretreatment ictal connectivity differences in children with CAE were associated with response to antiepileptic treatment. This is a possible mechanism for the variable treatment response seen in patients sharing the same epilepsy syndrome. Wiley Periodicals, Inc. © 2018 International League Against Epilepsy.

Dietary patterns in the French adult population: a study from the second French national cross-sectional dietary survey (INCA2) (2006-2007).

PubMed

Gazan, R; Béchaux, C; Crépet, A; Sirot, V; Drouillet-Pinard, P; Dubuisson, C; Havard, S

2016-07-01

Identification and characterisation of dietary patterns are needed to define public health policies to promote better food behaviours. The aim of this study was to identify the major dietary patterns in the French adult population and to determine their main demographic, socio-economic, nutritional and environmental characteristics. Dietary patterns were defined from food consumption data collected in the second French national cross-sectional dietary survey (2006-2007). Non-negative-matrix factorisation method, followed by a cluster analysis, was implemented to derive the dietary patterns. Logistic regressions were then used to determine their main demographic and socio-economic characteristics. Finally, nutritional profiles and contaminant exposure levels of dietary patterns were compared using ANOVA. Seven dietary patterns, with specific food consumption behaviours, were identified: 'Small eater', 'Health conscious', 'Mediterranean', 'Sweet and processed', 'Traditional', 'Snacker' and 'Basic consumer'. For instance, the Health-conscious pattern was characterised by a high consumption of low-fat and light products. Individuals belonging to this pattern were likely to be older and to have a better nutritional profile than the overall population, but were more exposed to many contaminants. Conversely, individuals of Snacker pattern were likely to be younger, consumed more highly processed foods, had a nutrient-poor profile but were exposed to a limited number of food contaminants. The study identified main dietary patterns in the French adult population with distinct food behaviours and specific demographic, socio-economic, nutritional and environmental features. Paradoxically, for better dietary patterns, potential health risks cannot be ruled out. Therefore, this study demonstrated the need to conduct a risk-benefit analysis to define efficient public health policies regarding diet.

Assessing the manufacturing tolerances and uniformity of CMOS compatible metamaterial fabrication

DOE Office of Scientific and Technical Information (OSTI.GOV)

Musick, Katherine M.; Wendt, Joel R.; Resnick, Paul J.

Here, the manufacturing tolerances of a stencil-lithography variant, membrane projection lithography, were investigated. In the first part of this work, electron beam lithography was used to create stencils with a range of linewidths. These patterns were transferred into the stencil membrane and used to pattern metallic lines on vertical silicon faces. Only the largest lines, with a nominal width of 84 nm, were resolved, resulting in 45 ± 10 nm (average ± standard deviation) as deposited with 135-nm spacing. Although written in the e-beam write software file as 84-nm in width, the lines exhibited linewidth bias. This can largely bemore » attributed to nonvertical sidewalls inherent to dry etching techniques that cause proportionally larger impact with decreasing feature size. The line edge roughness can be significantly attributed to the grain structure of the aluminum nitride stencil membrane. In the second part of this work, the spatial uniformity of optically defined (as opposed to e-beam written) metamaterial structures over large areas was assessed. A Fourier transform infrared spectrometer microscope was used to collect the reflection spectra of samples with optically defined vertical split ring from 25 spatially resolved 300 × 300 μm regions in a 1-cm 2 area. The technique is shown to provide a qualitative measure of the uniformity of the inclusions.« less

Assessing the manufacturing tolerances and uniformity of CMOS compatible metamaterial fabrication

DOE PAGES

Musick, Katherine M.; Wendt, Joel R.; Resnick, Paul J.; ...

2018-01-18

Here, the manufacturing tolerances of a stencil-lithography variant, membrane projection lithography, were investigated. In the first part of this work, electron beam lithography was used to create stencils with a range of linewidths. These patterns were transferred into the stencil membrane and used to pattern metallic lines on vertical silicon faces. Only the largest lines, with a nominal width of 84 nm, were resolved, resulting in 45 ± 10 nm (average ± standard deviation) as deposited with 135-nm spacing. Although written in the e-beam write software file as 84-nm in width, the lines exhibited linewidth bias. This can largely bemore » attributed to nonvertical sidewalls inherent to dry etching techniques that cause proportionally larger impact with decreasing feature size. The line edge roughness can be significantly attributed to the grain structure of the aluminum nitride stencil membrane. In the second part of this work, the spatial uniformity of optically defined (as opposed to e-beam written) metamaterial structures over large areas was assessed. A Fourier transform infrared spectrometer microscope was used to collect the reflection spectra of samples with optically defined vertical split ring from 25 spatially resolved 300 × 300 μm regions in a 1-cm 2 area. The technique is shown to provide a qualitative measure of the uniformity of the inclusions.« less

Developing New Rainfall Estimates to Identify the Likelihood of Agricultural Drought in Mesoamerica

NASA Astrophysics Data System (ADS)

Pedreros, D. H.; Funk, C. C.; Husak, G. J.; Michaelsen, J.; Peterson, P.; Lasndsfeld, M.; Rowland, J.; Aguilar, L.; Rodriguez, M.

2012-12-01

The population in Central America was estimated at ~40 million people in 2009, with 65% in rural areas directly relying on local agricultural production for subsistence, and additional urban populations relying on regional production. Mapping rainfall patterns and values in Central America is a complex task due to the rough topography and the influence of two oceans on either side of this narrow land mass. Characterization of precipitation amounts both in time and space is of great importance for monitoring agricultural food production for food security analysis. With the goal of developing reliable rainfall fields, the Famine Early warning Systems Network (FEWS NET) has compiled a dense set of historical rainfall stations for Central America through cooperation with meteorological services and global databases. The station database covers the years 1900-present with the highest density between 1970-2011. Interpolating station data by themselves does not provide a reliable result because it ignores topographical influences which dominate the region. To account for this, climatological rainfall fields were used to support the interpolation of the station data using a modified Inverse Distance Weighting process. By blending the station data with the climatological fields, a historical rainfall database was compiled for 1970-2011 at a 5km resolution for every five day interval. This new database opens the door to analysis such as the impact of sea surface temperature on rainfall patterns, changes to the typical dry spell during the rainy season, characterization of drought frequency and rainfall trends, among others. This study uses the historical database to identify the frequency of agricultural drought in the region and explores possible changes in precipitation patterns during the past 40 years. A threshold of 500mm of rainfall during the growing season was used to define agricultural drought for maize. This threshold was selected based on assessments of crop conditions from previous seasons, and was identified as an amount roughly corresponding to significant crop loss for maize, a major crop in most of the region. Results identify areas in central Honduras and Nicaragua as well as the Altiplano region in Guatemala that experienced 15 seasons of agricultural drought for the period May-July during the years 1970-2000. Preliminary results show no clear trend in rainfall, but further investigation is needed to confirm that agricultural drought is not becoming more frequent in this region.

Spectral characteristics and the extent of paleosols of the Palouse formation

NASA Technical Reports Server (NTRS)

Frazier, B. E.; Busacca, Alan; Cheng, Yaan; Wherry, David; Hart, Judy; Gill, Steve

1988-01-01

The objective of this study is to test the hypothesis that TM data is adequate in band selection and width and in spatial resolution to distinguish soil organic matter, iron oxide, and lime-silica contents to map several severity classes of erosion in soils of the Palouse region. The methodology used is as follows: (1) To develop spectral relationships from TM data that define the spatial distribution of soil areas by levels of (1) organic matter in the surface soil, (2) iron oxide and clay in exposed paleosol B horizons, and (3) lime-silica accumulations in exposed paleosol B horizons; (2) To compare areas determined by the method outlined in 1 to patterns interpreted from color aerial photos, and to ground observations on bare-soil fields; and (3) To define, on the basis of results of 1 and 2 to the extent possible, where exposed paleosols exist within fields that are not bare, but have a crop cover, and the distribution of desirable and undesirable soil properties in each field.

Macrofaunal Patterns in and around du Couedic and Bonney Submarine Canyons, South Australia

PubMed Central

Dittmann, Sabine; Sorokin, Shirley J.; Hendrycks, Ed

2015-01-01

Two South Australian canyons, one shelf-incising (du Couedic) and one slope-limited (Bonney) were compared for macrofaunal patterns on the shelf and slope that spanned three water masses. It was hypothesized that community structure would (H1) significantly differ by water mass, (H2) show significant regional differences and (H3) differ significantly between interior and exterior of each canyon. Five hundred and thirty-one species of macrofauna ≥1 mm were captured at 27 stations situated in depth stratified transects inside and outside the canyons from 100 to1500 m depth. The macrofauna showed a positive relationship to depth in abundance, biomass, species richness and community composition while taxonomic distinctness and evenness remained high at all depths. Biotic variation on the shelf was best defined by variation in bottom water primary production while sediment characteristics and bottom water oxygen, temperature and nutrients defined biotic variation at greater depth. Community structure differed significantly (p<0.01) among the three water masses (shelf-flowing South Australian current, upper slope Flinders current and lower slope Antarctic Intermediate Water) (H1). Although community differences between the du Couedic and Bonney regions were marginally above significance at p = 0.05 (H2), over half of the species captured were unique to each region. This supports the evidence from fish and megafaunal distributions that the du Couedic and Bonney areas are in different bioregions. Overall, the canyon interiors were not significantly different in community composition from the exterior (H3). However, both canyons had higher abundance and/or biomass, increased species dominance, different species composition and coarser sediments near the canyon heads compared to outside the canyons at the same depth (500 m), suggestive of heightened currents within the canyons that influence community composition there. At 1000–1500 m, the canyon interiors were depauperate, typical of V-shaped canyons elsewhere. The large number of species captured, given the relatively low sampling effort and focus on the larger macrofauna, support previous studies that identify the South Australian coast as a high biodiversity area. PMID:26618354

The heterogeneous ice shell thickness of Enceladus

NASA Astrophysics Data System (ADS)

Lucchetti, Alice; Pozzobon, Riccardo; Mazzarini, Francesco; Cremonese, Gabriele; Massironi, Matteo

2016-10-01

Saturn's moon Enceladus is the smallest Solar System body that presents an intense geologic activity on its surface. Plumes erupting from Enceladus' South Polar terrain (SPT) provide direct evidence of a reservoir of liquid below the surface. Previous analysis of gravity data determined that the ice shell above the liquid ocean must be 30-40 km thick from the South Pole up to 50° S latitude (Iess et al., 2014), however, understand the global or regional nature of the ocean beneath the ice crust is still challenging. To infer the thickness of the outer ice shell and prove the global extent of the ocean, we used the self-similar clustering method (Bonnet et al., 2001; Bour et al., 2002) to analyze the widespread fractures of the Enceladus's surface. The spatial distribution of fractures has been analyzed in terms of their self-similar clustering and a two-point correlation method was used to measure the fractal dimension of the fractures population (Mazzarini, 2004, 2010). A self-similar clustering of fractures is characterized by a correlation coefficient with a size range defined by a lower and upper cut-off, that represent a mechanical discontinuity and the thickness of the fractured icy crust, thus connected to the liquid reservoir. Hence, this method allowed us to estimate the icy shell thickness values in different regions of Enceladus from SPT up to northern regions.We mapped fractures in ESRI ArcGis environment in different regions of the satellite improving the recently published geological map (Crow-Willard and Pappalardo, 2015). On these regions we have taken into account the fractures, such as wide troughs and narrow troughs, located in well-defined geological units. Firstly, we analyzed the distribution of South Polar Region fracture patterns finding an ice shell thickness of ~ 31 km, in agreement with gravity measurements (Iess et al., 2014). Then, we applied the same approach to other four regions of the satellite inferring an increasing of the ice shell thickness from 31 to 70 km from the South Pole to northern regions. By these findings, we prove the global extent of the ocean underneath the ice crust of the satellite.

Does an Ability to Pattern Indicate That Our Thinking Is Mathematical?

ERIC Educational Resources Information Center

McCluskey, Catherine; Mitchelmore, Michael; Mulligan, Joanne

2013-01-01

Research affirms that pattern and structure underlie the development of a broad range of mathematical concepts. However, the concept of pattern also occurs in other fields. This theoretical paper explores pattern recognition, a neurological construct based on the world of Goldberg (2005), and pattern as defined in the field of mathematics to…

Diffusion imaging of cerebral white matter in persons who stutter: evidence for network-level anomalies

PubMed Central

Cai, Shanqing; Tourville, Jason A.; Beal, Deryk S.; Perkell, Joseph S.; Guenther, Frank H.; Ghosh, Satrajit S.

2013-01-01

Deficits in brain white matter have been a main focus of recent neuroimaging studies on stuttering. However, no prior study has examined brain connectivity on the global level of the cerebral cortex in persons who stutter (PWS). In the current study, we analyzed the results from probabilistic tractography between regions comprising the cortical speech network. An anatomical parcellation scheme was used to define 28 speech production-related ROIs in each hemisphere. We used network-based statistic (NBS) and graph theory to analyze the connectivity patterns obtained from tractography. At the network-level, the probabilistic corticocortical connectivity from the PWS group were significantly weaker than that from persons with fluent speech (PFS). NBS analysis revealed significant components in the bilateral speech networks with negative correlations with stuttering severity. To facilitate comparison with previous studies, we also performed tract-based spatial statistics (TBSS) and regional fractional anisotropy (FA) averaging. Results from tractography, TBSS and regional FA averaging jointly highlight the importance of several regions in the left peri-Rolandic sensorimotor and premotor areas, most notably the left ventral premotor cortex (vPMC) and middle primary motor cortex, in the neuroanatomical basis of stuttering. PMID:24611042

Diffusion imaging of cerebral white matter in persons who stutter: evidence for network-level anomalies.

PubMed

Cai, Shanqing; Tourville, Jason A; Beal, Deryk S; Perkell, Joseph S; Guenther, Frank H; Ghosh, Satrajit S

2014-01-01

Deficits in brain white matter have been a main focus of recent neuroimaging studies on stuttering. However, no prior study has examined brain connectivity on the global level of the cerebral cortex in persons who stutter (PWS). In the current study, we analyzed the results from probabilistic tractography between regions comprising the cortical speech network. An anatomical parcellation scheme was used to define 28 speech production-related ROIs in each hemisphere. We used network-based statistic (NBS) and graph theory to analyze the connectivity patterns obtained from tractography. At the network-level, the probabilistic corticocortical connectivity from the PWS group were significantly weaker than that from persons with fluent speech (PFS). NBS analysis revealed significant components in the bilateral speech networks with negative correlations with stuttering severity. To facilitate comparison with previous studies, we also performed tract-based spatial statistics (TBSS) and regional fractional anisotropy (FA) averaging. Results from tractography, TBSS and regional FA averaging jointly highlight the importance of several regions in the left peri-Rolandic sensorimotor and premotor areas, most notably the left ventral premotor cortex (vPMC) and middle primary motor cortex, in the neuroanatomical basis of stuttering.

Derivative Sign Patterns in Two Dimensions

ERIC Educational Resources Information Center

Schilling, Kenneth

2013-01-01

Given a function defined on a subset of the plane whose partial derivatives never change sign, the signs of the partial derivatives form a two-dimensional pattern. We explore what patterns are possible for various planar domains.

9 CFR 94.9 - Pork and pork products from regions where classical swine fever exists.

Code of Federal Regulations, 2011 CFR

2011-01-01

... the importation of swine and swine products. (b) The APHIS-defined EU CSF region is a single region of low-risk for CSF. (c) Except as provided in § 94.24 for the APHIS-defined EU CSF region, no fresh pork...

Long-acting nifedipine for hypertensive patients in the Middle East and Morocco: observations on efficacy and tolerability of monotherapy or combination therapy

PubMed Central

Ghoneim, Raafat AL; Omar, Abdalla Kamal; Sebastian, VJ; Kassab, Roland; Akijian, George; Hafiz, Meryem; Schmidt, Birgit

2013-01-01

Background The Middle Eastern and North African region of developing countries is associated with poor rates of blood pressure (BP) control and antihypertensive prescribing patterns. This post hoc analysis of data from an international observational study aimed to investigate the efficacy and tolerability of long-acting nifedipine (30 mg or 60 mg; monotherapy or in combination) in the Middle Eastern and Moroccan populations defined as having high cardiovascular risk. Methods This was a prospective, noninterventional, multicenter observational study. Observations from patients (aged ≥ 18 years) with treated or untreated hypertension from the Middle East (Jordan, Saudi Arabia, Kuwait, Lebanon, Qatar, United Arab Emirates, and Yemen) and Morocco are presented. Hypertension grade and cardiovascular risk were defined at baseline, and systolic/diastolic BP change was defined at post-baseline visits (≤3). Adverse events and ratings of therapy efficacy and patient/physician satisfaction were recorded. Results The study included 1466 patients from the Middle East and 524 from Morocco. Characteristics of the populations differed, with a more severe hypertension profile in Moroccan patients. Despite these differences, nifedipine reduced BP to a similar extent in each group, with efficacy dependent on cardiovascular risk factors such as hypertension grade and age. Few adverse drug reactions occurred and nifedipine was well-tolerated in both populations. Efficacy and satisfaction with therapy were rated highly. Conclusion Good rates of BP control were observed with nifedipine in patients with moderate-to-severe hypertension and high added risk. Published data in these countries suggest poor antihypertensive prescribing patterns and BP control; these data confirm this trend and suggest that suboptimal dosing may be prevalent. PMID:23807860

Analysis of chromosome 22 deletions in neurofibromatosis type 2-related tumors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wolff, R.K.; Frazer, K.A.; Jackler, R.K.

The neurofibromatosis type 2 (NF2) gene has been hypothesized to be a recessive tumor suppressor, with mutations at the same locus on chromosome 22 that lead to NF2 also leading to sporadic tumors of the types seen in NF2. Flanking markers for this gene have previously been defined as D22S1 centromeric and D22S28 telomeric. Identification of subregions of this interval that are consistently rearranged in the NF2-related tumors would aid in better defining the disease locus. To this end, the authors have compared tumor and constitutional DNAs, isolated from 39 unrelated patients with sporadic and NF2-associated acoustic neuromas, meningiomas, schwannomas,more » and ependymomas, at eight polymorphic loci on chromosome 22. Two of the tumors studied revealed loss-of-heterozygosity patterns, which is consistent with the presence of chromosome 22 terminal deletions. By using additional polymorphic markers, the terminal deletion breakpoint found in one of the tumors, an acoustic neuroma from an NF2 patient, was mapped within the previously defined NF2 region. The breakpoint occurred between the haplotyped markers D22S41/D22S46 and D22S56. This finding redefines the proximal flanking marker and localizes the NF2 gene between markers D22S41/D22S46 and D22S28. In addition, the authors identified a sporadic acoustic neuroma that reveals a loss-of-heterozygosity pattern consistent with mitotic recombination or deletion and reduplication, which are mechanisms not previously seen in studies of these tumors. This finding, while inconsistent with models of tumorigenesis that invoke single deletions and their gene-dosage effects, lends further support to the recessive tumor-suppressor model. 33 refs., 2 figs., 1 tab.« less

Analysis of chromosome 22 deletions in neurofibromatosis type 2-related tumors.

PubMed

Wolff, R K; Frazer, K A; Jackler, R K; Lanser, M J; Pitts, L H; Cox, D R

1992-09-01

The neurofibromatosis type 2 (NF2) gene has been hypothesized to be a recessive tumor suppressor, with mutations at the same locus on chromosome 22 that lead to NF2 also leading to sporadic tumors of the types seen in NF2. Flanking markers for this gene have previously been defined as D22S1 centromeric and D22S28 telomeric. Identification of subregions of this interval that are consistently rearranged in the NF2-related tumors would aid in better defining the disease locus. To this end, we have compared tumor and constitutional DNAs, isolated from 39 unrelated patients with sporadic and NF2-associated acoustic neuromas, meningiomas, schwannomas, and ependymomas, at eight polymorphic loci on chromosome 22. Two of the tumors studied revealed loss-of-heterozygosity patterns, which is consistent with the presence of chromosome 22 terminal deletions. By using additional polymorphic markers, the terminal deletion breakpoint found in one of the tumors, an acoustic neuroma from an NF2 patient, was mapped within the previously defined NF2 region. The breakpoint occurred between the haplotyped markers D22S41/D22S46 and D22S56. This finding redefines the proximal flanking marker and localizes the NF2 gene between markers D22S41/D22S46 and D22S28. In addition, we identified a sporadic acoustic neuroma that reveals a loss-of-heterozygosity pattern consistent with mitotic recombination or deletion and reduplication, which are mechanisms not previously seen in studies of these tumors. This finding, while inconsistent with models of tumorigenesis that invoke single deletions and their gene-dosage effects, lends further support to the recessive tumor-suppressor model.

Analysis of chromosome 22 deletions in neurofibromatosis type 2-related tumors.

PubMed Central

Wolff, R K; Frazer, K A; Jackler, R K; Lanser, M J; Pitts, L H; Cox, D R

1992-01-01

The neurofibromatosis type 2 (NF2) gene has been hypothesized to be a recessive tumor suppressor, with mutations at the same locus on chromosome 22 that lead to NF2 also leading to sporadic tumors of the types seen in NF2. Flanking markers for this gene have previously been defined as D22S1 centromeric and D22S28 telomeric. Identification of subregions of this interval that are consistently rearranged in the NF2-related tumors would aid in better defining the disease locus. To this end, we have compared tumor and constitutional DNAs, isolated from 39 unrelated patients with sporadic and NF2-associated acoustic neuromas, meningiomas, schwannomas, and ependymomas, at eight polymorphic loci on chromosome 22. Two of the tumors studied revealed loss-of-heterozygosity patterns, which is consistent with the presence of chromosome 22 terminal deletions. By using additional polymorphic markers, the terminal deletion breakpoint found in one of the tumors, an acoustic neuroma from an NF2 patient, was mapped within the previously defined NF2 region. The breakpoint occurred between the haplotyped markers D22S41/D22S46 and D22S56. This finding redefines the proximal flanking marker and localizes the NF2 gene between markers D22S41/D22S46 and D22S28. In addition, we identified a sporadic acoustic neuroma that reveals a loss-of-heterozygosity pattern consistent with mitotic recombination or deletion and reduplication, which are mechanisms not previously seen in studies of these tumors. This finding, while inconsistent with models of tumorigenesis that invoke single deletions and their gene-dosage effects, lends further support to the recessive tumor-suppressor model. Images Figure 1 Figure 2 PMID:1496981

A method to integrate patterned electrospun fibers with microfluidic systems to generate complex microenvironments for cell culture applications

PubMed Central

Wallin, Patric; Zandén, Carl; Carlberg, Björn; Hellström Erkenstam, Nina; Liu, Johan; Gold, Julie

2012-01-01

The properties of a cell’s microenvironment are one of the main driving forces in cellular fate processes and phenotype expression invivo. The ability to create controlled cell microenvironments invitro becomes increasingly important for studying or controlling phenotype expression in tissue engineering and drug discovery applications. This includes the capability to modify material surface properties within well-defined liquid environments in cell culture systems. One successful approach to mimic extra cellular matrix is with porous electrospun polymer fiber scaffolds, while microfluidic networks have been shown to efficiently generate spatially and temporally defined liquid microenvironments. Here, a method to integrate electrospun fibers with microfluidic networks was developed in order to form complex cell microenvironments with the capability to vary relevant parameters. Spatially defined regions of electrospun fibers of both aligned and random orientation were patterned on glass substrates that were irreversibly bonded to microfluidic networks produced in poly-dimethyl-siloxane. Concentration gradients obtained in the fiber containing channels were characterized experimentally and compared with values obtained by computational fluid dynamic simulations. Velocity and shear stress profiles, as well as vortex formation, were calculated to evaluate the influence of fiber pads on fluidic properties. The suitability of the system to support cell attachment and growth was demonstrated with a fibroblast cell line. The potential of the platform was further verified by a functional investigation of neural stem cell alignment in response to orientation of electrospun fibers versus a microfluidic generated chemoattractant gradient of stromal cell-derived factor 1 alpha. The described method is a competitive strategy to create complex microenvironments invitro that allow detailed studies on the interplay of topography, substrate surface properties, and soluble microenvironment on cellular fate processes. PMID:23781291

Dietary patterns in internal migrants in a continental country: A population-based study

PubMed Central

Carioca, Antonio Augusto Ferreira; Gorgulho, Bartira; Teixeira, Juliana Araujo; Fisberg, Regina Mara; Marchioni, Dirce Maria

2017-01-01

Objective The objective of this study was to assess the differences and similarities in dietary patterns among migrants and natives. Methods A population-based, cross-sectional study was conducted in the city of São Paulo. The study population included internal migrants, defined as individuals born outside São Paulo city who had lived in the city for ten years or longer. The final population (n = 999) was divided into three groups: natives of São Paulo (n = 354), migrants from the Southeast (n = 349) and migrants from the Northeast (n = 296). Factor and principal component analysis was employed to derive dietary patterns. The standardized scores were compared among groups using linear regression. Results Differences in income per capita, years of education, self-reported race, smoking habits, alcohol consumption, nutritional status and prevalence of hypertension were found for place of birth. Three dietary patterns were identified: prudent (salad dressings, vegetables, natural flavorings, fruits, whole-grain bread, white cheeses and juices), traditional (rice, beans, bread/toast/crackers, butter/margarine, whole milk, coffee/teas, sugar), and modern (sodas, pastries/sandwiches/pizzas, yellow cheeses, pastas, sauces, alcoholic beverages, sweets, processed meats). Compared to natives, migrants from the Southeast had an inversely proportional adherence to the modern pattern whereas migrants from the Northeast had an inverse association with the prudent and modern patterns and a positive association with the traditional pattern. Conclusions São Paulo natives and internal migrants from other regions of Brazil exhibited different dietary patterns. The results presented here add perspectives to be considered in the study of non-communicable diseases and its different incidences among migrants and natives. PMID:29036177

Evidence of Teleconnections between the Peruvian central Andes and Northeast Brazil during extreme rainfall events

NASA Astrophysics Data System (ADS)

Sulca, J. C.; Vuille, M. F.; Silva, F. Y.; Takahashi, K.

2013-12-01

Knowledge about changes in regional circulation and physical processes associated with extreme rainfall events in South America is limited. Here we investigate such events over the Mantaro basin (MB) located at (10°S-13°S; 73°W-76°W) in the central Peruvian Andes and Northeastern Brazil (NEB), located at (9°S-15°S; 39°W-46°W). Occasional dry and wet spells can be observed in both areas during the austral summer season. The main goal of this study is to investigate potential teleconnections between extreme rainfall events in MB and NEB during austral summer. We define wet (dry) spells as periods that last for at least 3 (5) consecutive days with rainfall above (below) the 70 (30) percentile. To identify the dates of ocurrence of these events, we used daily accumulated rainfall data from 14 climate stations located in the Mantaro basin for the period 1965 to 2002. In NEB we defined a rainfall index which is based on average daily gridded rainfall data within the region for the same period. Dry (wet spells) in the MB are associated with positive (negative) OLR anomalies which extend over much of the tropical Andes, indicating the large-scale nature of these events. At 200 hPa anomalous easterly (westerly) zonal winds aloft accompany wet (dry) spells. Composite anomalies of dry spells in MB reveal significant contemporaneous precipitation anomalies of the opposite sign over NEB, which suggest that intraseasonal precipitation variability over the two regions may be dynamically linked. Indeed upper-tropospheric circulation anomalies over the central Andes extend across South America and appear to be tied to an adjustment in the Bolivian High-Nordeste Low system. Dry (wet) spells in NEB are equally associated with a large-scale pattern of positive (negative) OLR anomalies; however, there are no related significant OLR anomalies over the MB during these events. Dry (wet) spells are associated with robust patterns of anomalous wind fields at both low and upper levels, caused by a changing position of the South Atlantic Convergence Zone (SACZ) toward the southwest (northeast). But, there is no coincident robust pattern of wind anomalies over the Mantaro Basin. In conclusion, dry spells in the Mantaro basin appear to be dynamically linked to wet spells in NEB, since 62% of all dry events in MB coincide with wet spells in NEB (35% of all events). The dynamical link explaining the observed teleconnection and the resulting dipole pattern between precipitation extremes in the MB and NEB region, respectively, appears to be related to intraseasonal variability in the Bolivian High - Nordeste Low system. Only 26.53% of all wet spells, however, coincide with dry spells in NEB (12.15% of all events). While circulation anomalies that affect precipitation extremes in the MB have the potential to also affect the precipitation characteristics in NEB, the opposite is not the case. Extreme events in NEB are primarily affected by NE-SW displacement in the SACZ, a mechanism that is of little relevance for precipitation extremes in the MB.

Planetary Boundary Layer Patterns, Height Variability and their Controls over the Indian Subcontinent with respect to Monsoon

NASA Astrophysics Data System (ADS)

Sathyanadh, A.; Karipot, A.; Prabhakaran, T.

2016-12-01

Planetary boundary layer (PBL) height and its controlling factors undergo large variations at different spatio-temporal scales over land regions. In the present study, Modern Era Retrospective analysis for Research and Applications (MERRA) data products are used to investigate variations of PBL height and its controls in relation to different phases of Indian monsoon. MERRA PBL height validations carried out against those estimated from radiosonde and Global Positioning System Radio Occultation atmospheric profiles revealed fairly good agreement. Different PBL patterns are identified in terms of maximum height, its time of occurrence and growth rate, and they vary with respect to geographical locations, terrain characteristics and monsoon circulation. The pre-monsoon boundary layers are the deepest over the region, often exceeding 4 km and grow at a rate of approximately 400 m hr-1. Large nocturnal BL depths, possibly related to weakly convective residual layers, are another feature noted during dry conditions. Monsoon BLs are generally shallower, except where rainfall is scanty. The break-monsoon periods have slightly deeper BLs than the active monsoon phase. The controlling factors for the observed boundary layer behaviour are investigated using supplementary MERRA datasets. Evaporative fraction is found to have dominant control on the PBL height varying with seasons and regions. The characteristics and controls of wet and dry boundary layer regimes over inland and coastal locations are different. The fractional diffusion (ratio of non-local and total diffusion) coefficient analyses indicated that enhanced entrainment during monsoon contributes to reduction in PBLH unlike in the dry period. The relationship between controls and PBLH are better defined over inland than coastal regions. The wavelet cross spectral analysis revealed temporal variations in dominant contributions from the controlling factors at different periodicities during the course of the year.

Quantitative fluorescence-polymerase chain reaction assay for the detection of the duplication of the Charcot Marie Tooth disease type 1A critical region.

PubMed

De Toffol, Simona; Bellone, Emilia; Dulcetti, Francesca; Ruggeri, Anna Maria; Maggio, Pietro Paolo; Pulimeno, Maria Rosaria; Mandich, Paola; Maggi, Federico; Simoni, Giuseppe; Grati, Francesca Romana

2010-04-01

Charcot Marie Tooth (CMT) syndrome is the most common hereditary peripheral neuropathy, with an incidence of about 1 in 2500. The subtype 1A (CMT1A) is caused by a tandem duplication of a 1.5-Mb region encompassing the PMP22 gene. Conventional short tandem repeat (STR) analysis can reveal this imbalance if a triallelic pattern, defining with certainty the presence of duplication, is present. In case of duplication with a biallelic pattern, it can only indicate a semiquantitative dosage of the fluorescence intensity ratio of the two fragments. In this study we developed a quantitative fluorescence-PCR using seven highly informative STRs within the CMT1A critical region that successfully disclosed or excluded the presence of the pathogenic imbalance in a cohort of 60 samples including 40 DNAs from samples with the CMT1A duplication previously characterized with two different molecular approaches, and 20 diagnostic samples from 10 members of a five-generation pedigree segregating CMT1A, 8 unrelated cases and 2 prenatal samples. The application of the quantitative fluorescence-PCR using STRs located in the critical region could be a reliable method to evaluate the presence of the PMP22 duplication for the diagnosis and classification of hereditary neuropathies in asymptomatic subjects with a family history of inherited neuropathy, in prenatal samples in cases with one affected parent, and in unrelated patients with a sporadic demyelinating neuropathy with clinical features resembling CMT (i.e., pes cavus with hammer toes) or with conduction velocities in the range of CMT1A.

Direct Measurement of Lung Motion Using Hyperpolarized Helium-3 MR Tagging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cai Jing; Miller, G. Wilson; Altes, Talissa A.

2007-07-01

Purpose: To measure lung motion between end-inhalation and end-exhalation using a hyperpolarized helium-3 (HP {sup 3}He) magnetic resonance (MR) tagging technique. Methods and Materials: Three healthy volunteers underwent MR tagging studies after inhalation of 1 L HP {sup 3}He gas diluted with nitrogen. Multiple-slice two-dimensional and volumetric three-dimensional MR tagged images of the lungs were obtained at end-inhalation and end-exhalation, and displacement vector maps were computed. Results: The grids of tag lines in the HP {sup 3}He MR images were well defined at end-inhalation and remained evident at end-exhalation. Displacement vector maps clearly demonstrated the regional lung motion and deformationmore » that occurred during exhalation. Discontinuity and differences in motion pattern between two adjacent lung lobes were readily resolved. Conclusions: Hyperpolarized helium-3 MR tagging technique can be used for direct in vivo measurement of respiratory lung motion on a regional basis. This technique may lend new insights into the regional pulmonary biomechanics and thus provide valuable information for the deformable registration of lung.« less

Parcellation of the human substantia nigra based on anatomical connectivity to the striatum☆

PubMed Central

Chowdhury, Rumana; Lambert, Christian; Dolan, Raymond J.; Düzel, Emrah

2013-01-01

Substantia nigra/ventral tegmental area (SN/VTA) subregions, defined by dopaminergic projections to the striatum, are differentially affected by health (e.g. normal aging) and disease (e.g. Parkinson's disease). This may have an impact on reward processing which relies on dopaminergic regions and circuits. We acquired diffusion tensor imaging (DTI) with probabilistic tractography in 30 healthy older adults to determine whether subregions of the SN/VTA could be delineated based on anatomical connectivity to the striatum. We found that a dorsomedial region of the SN/VTA preferentially connected to the ventral striatum whereas a more ventrolateral region connected to the dorsal striatum. These SN/VTA subregions could be characterised by differences in quantitative structural imaging parameters, suggesting different underlying tissue properties. We also observed that these connectivity patterns differentially mapped onto reward dependence personality trait. We show that tractography can be used to parcellate the SN/VTA into anatomically plausible and behaviourally meaningful compartments, an approach that may help future studies to provide a more fine-grained synopsis of pathological changes in the dopaminergic midbrain and their functional impact. PMID:23684858

Physical properties of Deucalionis, Eos, Xanthe-type units in the central equatorial region of Mars

NASA Technical Reports Server (NTRS)

Strickland, Edwin L., III

1992-01-01

Classification and mapping of surficial units in the central equatorial region of Mars (30 degrees N to 20 degrees S, 57 degrees E to 75 degrees W) using enhanced color images and Mars Consortium data, identified three distinct, high albedo, relatively red surficial units in regions with intermediate to high thermal inertias. These units have distinctive properties and morphologies, occur in different, well-defined areas, and show different seasonal and secular patterns of albedo change. Deucalionis units occupy the classical albedo area of Deucalionis Regio, south of Meridiani Sinus and Sabaeus Sinus, and adjacent areas. Eos forms a bright band that separates the dark, relatively blue Meridiani-type units that dominate the southern part of the study area from intermediate albedo, relatively red Oxia units common in the north. Xanthe forms moderately bright, relatively red, Type 1B crater-streaks and uniform sheet-deposits in and adjacent to parts of Chryse Planitia, including the Viking 1 landing site. Xanthe is always associated with Oxia deposits, and has significantly lower albedos than the Eos materials, which it can be confused with.

Climate warming and the recent treeline shift in the European alps: the role of geomorphological factors in high-altitude sites.

PubMed

Leonelli, Giovanni; Pelfini, Manuela; di Cella, Umberto Morra; Garavaglia, Valentina

2011-05-01

Global warming and the stronger regional temperature trends recently recorded over the European Alps have triggered several biological and physical dynamics in high-altitude environments. We defined the present treeline altitude in three valleys of a region in the western Italian Alps and reconstructed the past treeline position for the last three centuries in a nearly undisturbed site by means of a dendrochronological approach. We found that the treeline altitude in this region is mainly controlled by human impacts and geomorphological factors. The reconstruction of the altitudinal dynamics at the study site reveals that the treeline shifted upwards of 115 m over the period 1901-2000, reaching the altitude of 2505 m in 2000 and 2515 m in 2008. The recent treeline shift and the acceleration of tree colonization rates in the alpine belt can be mainly ascribed to the climatic input. However, we point out the increasing role of geomorphological factors in controlling the future treeline position and colonization patterns in high mountains.

Nonlinear analyses of interictal EEG map the brain interdependences in human focal epilepsy

NASA Astrophysics Data System (ADS)

Quyen, Michel Le Van; Martinerie, Jacques; Adam, Claude; Varela, Francisco J.

1999-03-01

The degree of interdependence between intracranial electroencephalographic (EEG) channels was investigated in epileptic patients with temporal lobe seizures during interictal (between seizures) periods. With a novel method to characterize nonlinear cross-predictability, that is, the predictability of one channel using another channel as data base, we demonstrated here a possibility to extract information on the spatio-temporal organization of interactions between multichannel recording sites. This method determines whether two channels contain common activity, and often, whether one channel contains activity induced by the activity of the other channel. In particular, the technique and the comparison with surrogate data demonstrated that transient large-scale nonlinear entrainments by the epileptogenic region can be identified, this with or without epileptic activity. Furthermore, these recurrent activities related with the epileptic foci occurred in well-defined spatio-temporal patterns. This suggests that the epileptogenic region can exhibit very subtle influences on other brain regions during an interictal period and raises the possibility that the cross-predictability analysis of interictal data may be used as a significant aid in locating epileptogenic foci.

Compositional variability in Mediterranean archaeofaunas from Upper Paleolithic Southwest Europe

NASA Astrophysics Data System (ADS)

Jones, Emily Lena

2018-03-01

Recent meta-analyses of Upper Paleolithic Southwestern European archaeofaunas (Jones, 2015, 2016) have identified a consistent "Mediterranean" cluster from the Last Glacial Maximum through the early Holocene, suggesting similarities in environment and/or consistency in hunting strategy across this region through time despite radical changes in climate. However, while these archaeofaunas from this cluster all derive from sites located within today's Mediterranean bioclimatic region, many of them are from locations far from the Mediterranean Sea - Atlantic Portugal, the Spanish Meseta - which today differ significantly from each other in biotic composition. In this paper, I explore clustering (through cluster analysis and non-metric multidimensional scaling) within the Mediterranean archaeofaunal group. I test for the influence of sample size as well as the geographic variables of site elevation, latitude, and longitude on variability in the large mammal portions of archaeofaunal assemblages. ANOVA shows no relationship between cluster-defined groups and site elevation or longitude; instead, site latitude appears to be a primary contributor to patterning. However, the overall compositional similarity of the Mediterranean archaeofaunas in this dataset suggests more consistency than variability in Upper Paleolithic hunting strategy in this region.

Human long intrinsically disordered protein regions are frequent targets of positive selection.

PubMed

Afanasyeva, Arina; Bockwoldt, Mathias; Cooney, Christopher R; Heiland, Ines; Gossmann, Toni I

2018-06-01

Intrinsically disordered regions occur frequently in proteins and are characterized by a lack of a well-defined three-dimensional structure. Although these regions do not show a higher order of structural organization, they are known to be functionally important. Disordered regions are rapidly evolving, largely attributed to relaxed purifying selection and an increased role of genetic drift. It has also been suggested that positive selection might contribute to their rapid diversification. However, for our own species, it is currently unknown whether positive selection has played a role during the evolution of these protein regions. Here, we address this question by investigating the evolutionary pattern of more than 6600 human proteins with intrinsically disordered regions and their ordered counterparts. Our comparative approach with data from more than 90 mammalian genomes uses a priori knowledge of disordered protein regions, and we show that this increases the power to detect positive selection by an order of magnitude. We can confirm that human intrinsically disordered regions evolve more rapidly, not only within humans but also across the entire mammalian phylogeny. They have, however, experienced substantial evolutionary constraint, hinting at their fundamental functional importance. We find compelling evidence that disordered protein regions are frequent targets of positive selection and estimate that the relative rate of adaptive substitutions differs fourfold between disordered and ordered protein regions in humans. Our results suggest that disordered protein regions are important targets of genetic innovation and that the contribution of positive selection in these regions is more pronounced than in other protein parts. © 2018 Afanasyeva et al.; Published by Cold Spring Harbor Laboratory Press.

A systematic intercomparison of regional flood frequency analysis models in a simulation framework

NASA Astrophysics Data System (ADS)

Ganora, Daniele; Laio, Francesco; Claps, Pierluigi

2015-04-01

Regional frequency analysis (RFA) is a well-established methodology to provide an estimate of the flood frequency curve (or other discharge-related variables), based on the fundamental concept of substituting temporal information at a site (no data or short time series) by exploiting observations at other sites (spatial information). Different RFA paradigms exist, depending on the way the information is transferred to the site of interest. Despite the wide use of such methodology, a systematic comparison between these paradigms has not been performed. The aim of this study is to provide a framework wherein carrying out the intercomparison: we thus synthetically generate data through Monte Carlo simulations for a number of (virtual) stations, following a GEV parent distribution; different scenarios can be created to represent different spatial heterogeneity patterns by manipulating the parameters of the parent distribution at each station (e.g. with a linear variation in space of the shape parameter of the GEV). A special case is the homogeneous scenario where each station record is sampled from the same parent distribution. For each scenario and each simulation, different regional models are applied to evaluate the 200-year growth factor at each station. Results are than compared to the exact growth factor of each station, which is known in our virtual world. Considered regional approaches include: (i) a single growth curve for the whole region; (ii) a multiple-region model based on cluster analysis which search for an adequate number of homogeneous subregions; (iii) a Region-of-Influence model which defines a homogeneous subregion for each site; (iv) a spatially-smooth estimation procedure based on linear regressions.. A further benchmark model is the at-site estimate based on the analysis of the local record. A comprehensive analysis of the results of the simulations shows that, if the scenario is homogeneous (no spatial variability), all the regional approaches have comparable performances. Moreover, as expected, regional estimates are much more reliable than the at-site estimates. If the scenario is heterogeneous, the performances of the regional models depend on the pattern of heterogeneity; in general, however, the spatially-smooth regional approach performs better than the others, and its performances improve for increasing record lengths. For heterogeneous scenarios, the at-site estimates appear to be comparably more efficient than in the homogeneous case, and in general less biased than the regional estimates.

Dynamics of cell wall elasticity pattern shapes the cell during yeast mating morphogenesis.

PubMed

Goldenbogen, Björn; Giese, Wolfgang; Hemmen, Marie; Uhlendorf, Jannis; Herrmann, Andreas; Klipp, Edda

2016-09-01

The cell wall defines cell shape and maintains integrity of fungi and plants. When exposed to mating pheromone, Saccharomyces cerevisiae grows a mating projection and alters in morphology from spherical to shmoo form. Although structural and compositional alterations of the cell wall accompany shape transitions, their impact on cell wall elasticity is unknown. In a combined theoretical and experimental approach using finite-element modelling and atomic force microscopy (AFM), we investigated the influence of spatially and temporally varying material properties on mating morphogenesis. Time-resolved elasticity maps of shmooing yeast acquired with AFM in vivo revealed distinct patterns, with soft material at the emerging mating projection and stiff material at the tip. The observed cell wall softening in the protrusion region is necessary for the formation of the characteristic shmoo shape, and results in wider and longer mating projections. The approach is generally applicable to tip-growing fungi and plants cells. © 2016 The Authors.

Detection, mapping and estimation of rate of spread of grass fires from southern African ERTS-1 imagery

NASA Technical Reports Server (NTRS)

Wightman, J. M.

1973-01-01

Sequential band-6 imagery of the Zambesi Basin of southern Africa recorded substantial changes in burn patterns resulting from late dry season grass fires. One example from northern Botswana, indicates that a fire consumed approximately 70 square miles of grassland over a 24-hour period. Another example from western Zambia indicates increased fire activity over a 19-day period. Other examples clearly define the area of widespread grass fires in Angola, Botswana, Rhodesia and Zambia. From the fire patterns visible on the sequential portions of the imagery, and the time intervals involved, the rates of spread of the fires are estimated and compared with estimates derived from experimental burning plots in Zambia and Canada. It is concluded that sequential ERTS-1 imagery, of the quality studied, clearly provides the information needed to detect and map grass fires and to monitor their rates of spread in this region during the late dry season.

Short term load forecasting of anomalous load using hybrid soft computing methods

NASA Astrophysics Data System (ADS)

Rasyid, S. A.; Abdullah, A. G.; Mulyadi, Y.

2016-04-01

Load forecast accuracy will have an impact on the generation cost is more economical. The use of electrical energy by consumers on holiday, show the tendency of the load patterns are not identical, it is different from the pattern of the load on a normal day. It is then defined as a anomalous load. In this paper, the method of hybrid ANN-Particle Swarm proposed to improve the accuracy of anomalous load forecasting that often occur on holidays. The proposed methodology has been used to forecast the half-hourly electricity demand for power systems in the Indonesia National Electricity Market in West Java region. Experiments were conducted by testing various of learning rate and learning data input. Performance of this methodology will be validated with real data from the national of electricity company. The result of observations show that the proposed formula is very effective to short-term load forecasting in the case of anomalous load. Hybrid ANN-Swarm Particle relatively simple and easy as a analysis tool by engineers.

Synchrotron-based dynamic computed tomography of tissue motion for regional lung function measurement

PubMed Central

Dubsky, Stephen; Hooper, Stuart B.; Siu, Karen K. W.; Fouras, Andreas

2012-01-01

During breathing, lung inflation is a dynamic process involving a balance of mechanical factors, including trans-pulmonary pressure gradients, tissue compliance and airway resistance. Current techniques lack the capacity for dynamic measurement of ventilation in vivo at sufficient spatial and temporal resolution to allow the spatio-temporal patterns of ventilation to be precisely defined. As a result, little is known of the regional dynamics of lung inflation, in either health or disease. Using fast synchrotron-based imaging (up to 60 frames s−1), we have combined dynamic computed tomography (CT) with cross-correlation velocimetry to measure regional time constants and expansion within the mammalian lung in vivo. Additionally, our new technique provides estimation of the airflow distribution throughout the bronchial tree during the ventilation cycle. Measurements of lung expansion and airflow in mice and rabbit pups are shown to agree with independent measures. The ability to measure lung function at a regional level will provide invaluable information for studies into normal and pathological lung dynamics, and may provide new pathways for diagnosis of regional lung diseases. Although proof-of-concept data were acquired on a synchrotron, the methodology developed potentially lends itself to clinical CT scanning and therefore offers translational research opportunities. PMID:22491972

Combining bathymetry, latitude, and phylogeny to understand the distribution of deep Atlantic hydroids (Cnidaria)

NASA Astrophysics Data System (ADS)

Fernandez, Marina O.; Marques, Antonio C.

2018-03-01

Water depth is associated with significant environmental changes and gradients that, together with biotic, geological, and evolutionary processes, define bathymetric ranges of individuals, populations, species, and even communities. However, inferences on bathymetric ranges of marine invertebrates are usually based on a few taxa or on restricted regional scales. In this study, we present a comprehensive literature survey of hydroids for the Atlantic Ocean and adjacent Arctic and Antarctic seas for records deeper than 50 m. We used these records in bathymetrical analyses along latitude and compared major patterns under an evolutionary framework. Our results show that hydroids are frequent inhabitants of the deep sea with mainly eurybathic species that extend their distributions from shallower to deeper waters, being rarely exclusively bathyal or abyssal. We also found increasing bathymetric ranges with mean depths of occurrence of the species for both families and regions. Moreover, vertical distribution proved to be taxonomically and regionally dependent, with reduced eurybathy in "Antarctic" species but increased eurybathy in "Tropical" and "Subtropical North" regions. Data also support early colonization of the deep sea in the evolution of the group. Finally, the unequal number of records across latitudes, scant at Equatorial and southern Tropical latitudes, provides evidence to the historically uneven sampling effort in the different regions of the Atlantic.

Global Patterns of Guild Composition and Functional Diversity of Spiders

PubMed Central

Cardoso, Pedro; Pekár, Stano; Jocqué, Rudy; Coddington, Jonathan A.

2011-01-01

The objectives of this work are: (1) to define spider guilds for all extant families worldwide; (2) test if guilds defined at family level are good surrogates of species guilds; (3) compare the taxonomic and guild composition of spider assemblages from different parts of the world; (4) compare the taxonomic and functional diversity of spider assemblages and; (5) relate functional diversity with habitat structure. Data on foraging strategy, prey range, vertical stratification and circadian activity was collected for 108 families. Spider guilds were defined by hierarchical clustering. We searched for inconsistencies between family guild placement and the known guild of each species. Richness and abundance per guild before and after correcting guild placement were compared, as were the proportions of each guild and family between all possible pairs of sites. Functional diversity per site was calculated based on hierarchical clustering. Eight guilds were discriminated: (1) sensing, (2) sheet, (3) space, and (4) orb web weavers; (5) specialists; (6) ambush, (7) ground, and (8) other hunters. Sixteen percent of the species richness corresponding to 11% of all captured individuals was incorrectly attributed to a guild by family surrogacy; however, the correlation of uncorrected vs. corrected guilds was invariably high. The correlation of guild richness or abundances was generally higher than the correlation of family richness or abundances. Functional diversity was not always higher in the tropics than in temperate regions. Families may potentially serve as ecological surrogates for species. Different families may present similar roles in the ecosystems, with replacement of some taxa by other within the same guild. Spiders in tropical regions seem to have higher redundancy of functional roles and/or finer resource partitioning than in temperate regions. Although species and family diversity were higher in the tropics, functional diversity seems to be also influenced by altitude and habitat structure. PMID:21738772

Enhanced disease characterization through multi network functional normalization in fMRI.

PubMed

Çetin, Mustafa S; Khullar, Siddharth; Damaraju, Eswar; Michael, Andrew M; Baum, Stefi A; Calhoun, Vince D

2015-01-01

Conventionally, structural topology is used for spatial normalization during the pre-processing of fMRI. The co-existence of multiple intrinsic networks which can be detected in the resting brain are well-studied. Also, these networks exhibit temporal and spatial modulation during cognitive task vs. rest which shows the existence of common spatial excitation patterns between these identified networks. Previous work (Khullar et al., 2011) has shown that structural and functional data may not have direct one-to-one correspondence and functional activation patterns in a well-defined structural region can vary across subjects even for a well-defined functional task. The results of this study and the existence of the neural activity patterns in multiple networks motivates us to investigate multiple resting-state networks as a single fusion template for functional normalization for multi groups of subjects. We extend the previous approach (Khullar et al., 2011) by co-registering multi group of subjects (healthy control and schizophrenia patients) and by utilizing multiple resting-state networks (instead of just one) as a single fusion template for functional normalization. In this paper we describe the initial steps toward using multiple resting-state networks as a single fusion template for functional normalization. A simple wavelet-based image fusion approach is presented in order to evaluate the feasibility of combining multiple functional networks. Our results showed improvements in both the significance of group statistics (healthy control and schizophrenia patients) and the spatial extent of activation when a multiple resting-state network applied as a single fusion template for functional normalization after the conventional structural normalization. Also, our results provided evidence that the improvement in significance of group statistics lead to better accuracy results for classification of healthy controls and schizophrenia patients.

Teleconnections in the Presence of Climate Change: A Case Study of the Annular Modes

NASA Astrophysics Data System (ADS)

Gerber, Edwin; Baldwin, Mark

2010-05-01

Long model integrations of future and past climates present a problem for defining teleconnection patterns through Empirical Orthogonal Function (EOF) or correlation analysis when trends in the underlying climate begin to dominate the covariance structure. Similar issues may soon appear in observations as the record becomes longer, especially if climate trends accelerate. The Northern and Southern Annular Modes provide a prime example, because the poleward shift of the jet streams strongly projects onto these patterns, particularly in the Southern Hemisphere. Climate forecasts of the 21st century by chemistry climate models provide a case study. Computation of the annular modes in these long data sets with secular trends requires refinement of the standard definition of the annular mode, and a more robust procedure that allows for slowly varying trends is established and verified. The new procedure involves two key changes. First, the global mean geopotential height is removed at each time step before computing anomalies. This is particularly important high in the atmosphere, where seasonal variations in geopotential height become significant, and filters out trends due to changes in the temperature structure of the atmosphere. Pattern definition can be very sensitive near the tropopause, as regions of the atmosphere that used to be more of stratospheric character begin to take on tropospheric characteristics as the tropopause rises. The second change is to define anomalies relative to a slowly evolving seasonal climatology, so that the covariance structure reflects internal variability. Once these changes are accounted for, it is found that the zonal mean variability of the atmosphere stays remarkably constant, despite significant changes in the baseline climate forecast for the rest of the century. This stability of the internal variability makes it possible to relate trends in climate to teleconnections.

Annual trend patterns of phytoplankton species abundance belie homogeneous taxonomical group responses to climate in the NE Atlantic upwelling.

PubMed

Bode, Antonio; Estévez, M Graciela; Varela, Manuel; Vilar, José A

2015-09-01

Phytoplankton is a sentinel of marine ecosystem change. Composed by many species with different life-history strategies, it rapidly responds to environment changes. An analysis of the abundance of 54 phytoplankton species in Galicia (NW Spain) between 1989 and 2008 to determine the main components of temporal variability in relation to climate and upwelling showed that most of this variability was stochastic, as seasonality and long term trends contributed to relatively small fractions of the series. In general, trends appeared as non linear, and species clustered in 4 groups according to the trend pattern but there was no defined pattern for diatoms, dinoflagellates or other groups. While, in general, total abundance increased, no clear trend was found for 23 species, 14 species decreased, 4 species increased during the early 1990s, and only 13 species showed a general increase through the series. In contrast, series of local environmental conditions (temperature, stratification, nutrients) and climate-related variables (atmospheric pressure indices, upwelling winds) showed a high fraction of their variability in deterministic seasonality and trends. As a result, each species responded independently to environmental and climate variability, measured by generalized additive models. Most species showed a positive relationship with nutrient concentrations but only a few showed a direct relationship with stratification and upwelling. Climate variables had only measurable effects on some species but no common response emerged. Because its adaptation to frequent disturbances, phytoplankton communities in upwelling ecosystems appear less sensitive to changes in regional climate than other communities characterized by short and well defined productive periods. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Developmental distribution of the plasma membrane-enriched proteome in the maize primary root growth zone.

PubMed

Zhang, Zhe; Voothuluru, Priyamvada; Yamaguchi, Mineo; Sharp, Robert E; Peck, Scott C

2013-01-01

Within the growth zone of the maize primary root, there are well-defined patterns of spatial and temporal organization of cell division and elongation. However, the processes underlying this organization remain poorly understood. To gain additional insights into the differences amongst the defined regions, we performed a proteomic analysis focusing on fractions enriched for plasma membrane (PM) proteins. The PM is the interface between the plant cell and the apoplast and/or extracellular space. As such, it is a key structure involved in the exchange of nutrients and other molecules as well as in the integration of signals that regulate growth and development. Despite the important functions of PM-localized proteins in mediating these processes, a full understanding of dynamic changes in PM proteomes is often impeded by low relative concentrations relative to total proteins. Using a relatively simple strategy of treating microsomal fractions with Brij-58 detergent to enrich for PM proteins, we compared the developmental distribution of proteins within the root growth zone which revealed a number of previously known as well as novel proteins with interesting patterns of abundance. For instance, the quantitative proteomic analysis detected a gradient of PM aquaporin proteins similar to that previously reported using immunoblot analyses, confirming the veracity of this strategy. Cellulose synthases increased in abundance with increasing distance from the root apex, consistent with expected locations of cell wall deposition. The similar distribution pattern for Brittle-stalk-2-like protein implicates that this protein may also have cell wall related functions. These results show that the simplified PM enrichment method previously demonstrated in Arabidopsis can be successfully applied to completely unrelated plant tissues and provide insights into differences in the PM proteome throughout growth and development zones of the maize primary root.

History of fault slip and interaction with deltaic depostion from the middle Miocene to the Present - Barataria Fault, coastal Louisiana

NASA Astrophysics Data System (ADS)

McLindon, C.

2017-12-01

The Barataria fault is a major component of the Terrebonne Trough, a structural system of faults and salt domes underlying coastal Louisiana. High-quality 3-D seismic reflection data, industry well logs, micro-paleontological data and published literature on regional depositional patterns are integrated to provide an evolutionary history of the Barataria fault. The fault is a segment within a series of south-dipping normal faults that define the northern boundary of the Terrebonne Trough. The fault segment tips at depth interact with the Lake Washington and Bay de Chene salt domes, which appear to have limited its along-strike length. This study shows that the Barataria fault has exhibited continuous but episodic slip since at least the middle Miocene and through the present. Periods of maximum rates of fault slip are related to periods of maximum rates of sediment accumulation associated with Miocene deltaic deposition. The expansion of interval thickness between biostratigraphic markers in the hanging wall section of the fault relative to the footwall section (expansion index) indicate that rates of subsidence on the footwall during active fault slip were substantially greater than on the footwall. Pliocene-Pleistocene stratigraphic intervals exhibiting lower expansion indexes indicate that the fault remained active, but with a pattern of slower slip rate in which stratigraphic thickening was more limited to the area immediately adjacent to the fault. The Barataria fault defines the modern-day width of Barataria Bay, and also has a surface expression in the coastal marsh indicating that recent episodic slip has been associated with patterns of Holocene deltaic deposition.

Lineage-specific responses of microbial communities to environmental change.

PubMed

Youngblut, Nicholas D; Shade, Ashley; Read, Jordan S; McMahon, Katherine D; Whitaker, Rachel J

2013-01-01

A great challenge facing microbial ecology is how to define ecologically relevant taxonomic units. To address this challenge, we investigated how changing the definition of operational taxonomic units (OTUs) influences the perception of ecological patterns in microbial communities as they respond to a dramatic environmental change. We used pyrosequenced tags of the bacterial V2 16S rRNA region, as well as clone libraries constructed from the cytochrome oxidase C gene ccoN, to provide additional taxonomic resolution for the common freshwater genus Polynucleobacter. At the most highly resolved taxonomic scale, we show that distinct genotypes associated with the abundant Polynucleobacter lineages exhibit divergent spatial patterns and dramatic changes over time, while the also abundant Actinobacteria OTUs are highly coherent. This clearly demonstrates that different bacterial lineages demand different taxonomic definitions to capture ecological patterns. Based on the temporal distribution of highly resolved taxa in the hypolimnion, we demonstrate that change in the population structure of a single genotype can provide additional insight into the mechanisms of community-level responses. These results highlight the importance and feasibility of examining ecological change in microbial communities across taxonomic scales while also providing valuable insight into the ecological characteristics of ecologically coherent groups in this system.

Low Functional β-Diversity Despite High Taxonomic β-Diversity among Tropical Estuarine Fish Communities

PubMed Central

Villéger, Sébastien; Miranda, Julia Ramos; Hernandez, Domingo Flores; Mouillot, David

2012-01-01

The concept of β-diversity, defined as dissimilarity among communities, has been widely used to investigate biodiversity patterns and community assembly rules. However, in ecosystems with high taxonomic β-diversity, due to marked environmental gradients, the level of functional β-diversity among communities is largely overlooked while it may reveal processes shaping community structure. Here, decomposing biodiversity indices into α (local) and γ (regional) components, we estimated taxonomic and functional β-diversity among tropical estuarine fish communities, through space and time. We found extremely low functional β-diversity values among fish communities (<1.5%) despite high dissimilarity in species composition and species dominance. Additionally, in contrast to the high α and γ taxonomic diversities, α and γ functional diversities were very close to the minimal value. These patterns were caused by two dominant functional groups which maintained a similar functional structure over space and time, despite the strong dissimilarity in taxonomic structure along environmental gradients. Our findings suggest that taxonomic and functional β-diversity deserve to be quantified simultaneously since these two facets can show contrasting patterns and the differences can in turn shed light on community assembly rules. PMID:22792395

A typology of street patterns.

PubMed

Louf, Rémi; Barthelemy, Marc

2014-12-06

We propose a quantitative method to classify cities according to their street pattern. We use the conditional probability distribution of shape factor of blocks with a given area and define what could constitute the 'fingerprint' of a city. Using a simple hierarchical clustering method, these fingerprints can then serve as a basis for a typology of cities. We apply this method to a set of 131 cities in the world, and at an intermediate level of the dendrogram, we observe four large families of cities characterized by different abundances of blocks of a certain area and shape. At a lower level of the classification, we find that most European cities and American cities in our sample fall in their own sub-category, highlighting quantitatively the differences between the typical layouts of cities in both regions. We also show with the example of New York and its different boroughs, that the fingerprint of a city can be seen as the sum of the ones characterizing the different neighbourhoods inside a city. This method provides a quantitative comparison of urban street patterns, which could be helpful for a better understanding of the causes and mechanisms behind their distinct shapes. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Encoding Gaussian curvature in glassy and elastomeric liquid crystal solids

PubMed Central

Mostajeran, Cyrus; Ware, Taylor H.; White, Timothy J.

2016-01-01

We describe shape transitions of thin, solid nematic sheets with smooth, preprogrammed, in-plane director fields patterned across the surface causing spatially inhomogeneous local deformations. A metric description of the local deformations is used to study the intrinsic geometry of the resulting surfaces upon exposure to stimuli such as light and heat. We highlight specific patterns that encode constant Gaussian curvature of prescribed sign and magnitude. We present the first experimental results for such programmed solids, and they qualitatively support theory for both positive and negative Gaussian curvature morphing from flat sheets on stimulation by light or heat. We review logarithmic spiral patterns that generate cone/anti-cone surfaces, and introduce spiral director fields that encode non-localized positive and negative Gaussian curvature on punctured discs, including spherical caps and spherical spindles. Conditions are derived where these cap-like, photomechanically responsive regions can be anchored in inert substrates by designing solutions that ensure compatibility with the geometric constraints imposed by the surrounding media. This integration of such materials is a precondition for their exploitation in new devices. Finally, we consider the radial extension of such director fields to larger sheets using nematic textures defined on annular domains. PMID:27279777

[Consumption of nonsteroidal anti-inflammatory agents in primary care in Costa Rica: changing patterns and geographical variability].

PubMed

Morera Salas, Melvin; Aparicio Llanos, Amada; Xirinachs Salazar, Yanira; Barber Pérez, Patricia

2007-01-01

To determine changing patterns and variability in consumption of classic nonsteroidal anti-inflammatory drugs (NSAIDs) among the health areas in Costa Rica between 2000 and 2005. The drugs studied were ibuprofen, indomethacin, penicillamine, sulindac, tenoxicam, and diclofenac sodium. To measure consumption, we used the defined daily dose per 1,000 inhabitants per day (DID). To analyze variability, the coefficient of variation weighed by the population size (CVw), extremal ratio, interquartile ratio, dot plot and map graphs were used. From 2000-2005, NSAID consumption increased by 48% and the annual cost rose by 184%. The drugs with greatest consumption and participation in cost were sulindac and indomethacin. NSAID consumption varied between 0.1 and 61.8 DID according to health areas, with a CVw of 66.8%. Variability was greatest with penicillamine (CVw = 449.89%) and tenoxicam (CVw = 315.26%). Clearly differentiated geographical patterns in NSAID consumption were found in Costa Rica, with very different rates within the same region. According to the results obtained, two factors associated with this variability were the supply of health services and the percentage of the population aged 65 years or more within the catchment area.

A review of the Southern Oscillation - Oceanic-atmospheric circulation changes and related rainfall anomalies

NASA Technical Reports Server (NTRS)

Kousky, V. E.; Kagano, M. T.; Cavalcanti, I. F. A.

1984-01-01

The region of South America is emphasized in the present consideration of the Southern Oscillation (SO) oceanic and atmospheric circulation changes. The persistence of climate anomalies associated with El Nino-SO events is due to strong atmosphere-ocean coupling. Once initiated, the SO follows a certain sequence of events with clearly defined effects on tropical and subtropical rainfall. Excessive rainfall related to the SO in the central and eastern Pacific, Peru, Ecuador, and southern Brazil, are complemented by drought in Australia, Indonesia, India, West Africa, and northeast Brazil. El Nino-SO events are also associated with dramatic changes in the tropospheric flow pattern over a broad area of both hemispheres.

Continuing Medical Education

PubMed Central

Cameron, Douglas G.

1965-01-01

The proper role of departments of continuing medical education in the medical faculties of universities needs to be more clearly defined. Much of the initiative for the development of extramural postgraduate instruction in this country came from organized medicine. The individual practising doctor has traditionally made his needs known most effectively through his professional organizations and should be encouraged to continue to do so. The individual doctor, professional organizations, hospitals and medical schools are all vital elements in any successful program of continuing medical education. A variety of administrative patterns may well emerge, each adapted specially to the region it serves. With a sense of urgency and the co-operation of all concerned, rapid progress in this important field is clearly possible. PMID:14278032

Multivariate approach to matrimonial mobility in Catalonia.

PubMed

Calafell, F; Hernández, M

1993-10-01

Matrimonial mobility in Catalonia was studied using 1986 census data. Comarca (a geographic division) of birth was used as the population unit, and a measure of affinity (a statistical distance) between comarques in spouse geographic origin was defined. This distance was analyzed with multivariate methods drawn from numerical taxonomy to detect any discontinuities in matrimonial mobility and gene flow between comarques. Results show a three-level pattern of gene flow in Catalonia: (1) a strong endogamy within comarques; (2) a 100-km matrimonial circle around every comarca; and (3) the capital, Barcelona, which attracts migrants from all over Catalonia. The regionalization in matrimonial mobility follows the geographically clear-cut groups of comarques almost exactly.

Numerical-assisted design of a wind tunnel used in the estimation of volatilization from water, waste or soil.

PubMed

Baléo, J N; Le Cloirec, P

2006-04-01

Numerical simulations of the flow inside two wind tunnel geometries used for determining emission volatilization have been conducted. The flow pattern was examined in a plane close to the emitting surface. A reduced surface, characterizing the low velocity zones in this plane, has been defined. The proposed geometry modification, consisting of a convergent/divergent system, decreases the low velocity regions by a factor ranging between 2 and 3.5. Large vortices present in the conventional configuration are almost eliminated. The new velocity distribution, close to the emitting surface, is more uniform and should therefore generate a more efficient mass transfer to the flowing air.

Regional Patterns of Communication in the United States: A Theoretical Perspective.

ERIC Educational Resources Information Center

Andersen, Peter A.; And Others

1987-01-01

Provides the rationale for a systematic study of regional patterns of communication in the United States. Conceptualizes regionalism, appraises regional influences on communication, and establishes their significance. Describes regional development of the U.S. and proposes a program of regional research on U.S. communication. Examines deficiencies…

Regional climate and vegetation response to orbital forcing within the mid-Pliocene Warm Period: A study using HadCM3

NASA Astrophysics Data System (ADS)

Prescott, C. L.; Dolan, A. M.; Haywood, A. M.; Hunter, S. J.; Tindall, J. C.

2018-02-01

Regional climate and environmental variability in response to orbital forcing during interglacial events within the mid-Piacenzian (Pliocene) Warm Period (mPWP; 3.264-3.025 Ma) has been rarely studied using climate and vegetation models. Here we use climate and vegetation model simulations to predict changes in regional vegetation patterns in response to orbital forcing for four different interglacial events within the mPWP (Marine Isotope Stages (MIS) G17, K1, KM3 and KM5c). The efficacy of model-predicted changes in regional vegetation is assessed by reference to selected high temporal resolution palaeobotanical studies that are theoretically capable of discerning vegetation patterns for the selected interglacial stages. Annual mean surface air temperatures for the studied interglacials are between 0.4 °C to 0.7 °C higher than a comparable Pliocene experiment using modern orbital parameters. Increased spring/summer and reduced autumn/winter insolation in the Northern Hemisphere during MIS G17, K1 and KM3 enhances seasonality in surface air temperature. The two most robust and notable regional responses to this in vegetation cover occur in North America and continental Eurasia, where forests are replaced by more open-types of vegetation (grasslands and shrubland). In these regions our model results appear to be inconsistent with local palaeobotanical data. The orbitally driven changes in seasonal temperature and precipitation lead to a 30% annual reduction in available deep soil moisture (2.0 m from surface), a critical parameter for forest growth, and subsequent reduction in the geographical coverage of forest-type vegetation; a phenomenon not seen in comparable simulations of Pliocene climate and vegetation run with a modern orbital configuration. Our results demonstrate the importance of examining model performance under a range of realistic orbital forcing scenarios within any defined time interval (e.g. mPWP). Additional orbitally resolved records of regional vegetation are needed to further examine the validity of model-predicted regional climate and vegetation responses in greater detail.

Females and males are highly similar in language performance and cortical activation patterns during verb generation.

PubMed

Allendorfer, Jane B; Lindsell, Christopher J; Siegel, Miriam; Banks, Christi L; Vannest, Jennifer; Holland, Scott K; Szaflarski, Jerzy P

2012-10-01

To test the existence of sex differences in cortical activation during verb generation when performance is controlled for. Twenty male and 20 female healthy adults underwent functional magnetic resonance imaging (fMRI) using a covert block-design verb generation task (BD-VGT) and its event-related version (ER-VGT) that allowed for intra-scanner recordings of overt responses. Task-specific activations were determined using the following contrasts: BD-VGT covert generation>finger-tapping; ER-VGT overt generation>repetition; ER-VGT overt>covert generation. Lateral cortical regions activated during each contrast were used for calculating language lateralization index scores. Voxelwise regressions were used to determine sex differences in activation, with and without controlling for performance. Each brain region showing male/female activation differences for ER-VGT overt generation>repetition (isolating noun-verb association) was defined as a region of interest (ROI). For each subject, the signal change in each ROI was extracted, and the association between ER-VGT activation related to noun-verb association and performance was assessed separately for each sex. Males and females performed similarly on language assessments, had similar patterns of language lateralization, and exhibited similar activation patterns for each fMRI task contrast. Regression analysis controlling for overt intra-scanner performance either abolished (BD-VGT) or reduced (ER-VGT) the observed differences in activation between sexes. The main difference between sexes occurred during ER-VGT processing of noun-verb associations, where males showed greater activation than females in the right middle/superior frontal gyrus (MFG/SFG) and the right caudate/anterior cingulate gyrus (aCG) after controlling for performance. Better verb generation performance was associated with increased right caudate/aCG activation in males and with increased right MFG/SFG activation in females. Males and females exhibit similar activation patterns during verb generation fMRI, and controlling for intra-scanner performance reduces or even abolishes sex differences in language-related activation. These results suggest that previous findings of sex differences in neuroimaging studies that did not control for task performance may reflect false positives. Copyright © 2011 Elsevier Srl. All rights reserved.

Transcription factors define the neuroanatomical organization of the medullary reticular formation

PubMed Central

Gray, Paul A.

2013-01-01

The medullary reticular formation contains large populations of inadequately described, excitatory interneurons that have been implicated in multiple homeostatic behaviors including breathing, viserosensory processing, vascular tone, and pain. Many hindbrain nuclei show a highly stereotyped pattern of localization across vertebrates suggesting a strong underlying genetic organization. Whether this is true for neurons within the reticular regions of hindbrain is unknown. Hindbrain neurons are derived from distinct developmental progenitor domains each of which expresses distinct patterns of transcription factors (TFs). These neuronal populations have distinct characteristics such as transmitter identity, migration, and connectivity suggesting developmentally expressed TFs might identify unique subpopulations of neurons within the reticular formation. A fate-mapping strategy using perinatal expression of reporter genes within Atoh1, Dbx1, Lmx1b, and Ptf1a transgenic mice coupled with immunohistochemistry (IHC) and in situ hybridization (ISH) were used to address the developmental organization of a large subset of reticular formation glutamatergic neurons. All hindbrain lineages have relatively large populations that extend the entire length of the hindbrain. Importantly, the location of neurons within each lineage was highly constrained. Lmx1b- and Dbx1- derived populations were both present in partially overlapping stripes within the reticular formation extending from dorsal to ventral brain. Within each lineage, distinct patterns of gene expression and organization were localized to specific hindbrain regions. Rostro-caudally sub-populations differ sequentially corresponding to proposed pseudo-rhombomereic boundaries. Dorsal-ventrally, sub-populations correspond to specific migratory positions. Together these data suggests the reticular formation is organized by a highly stereotyped developmental logic. PMID:23717265

Transcription factors define the neuroanatomical organization of the medullary reticular formation.

PubMed

Gray, Paul A

2013-01-01

The medullary reticular formation contains large populations of inadequately described, excitatory interneurons that have been implicated in multiple homeostatic behaviors including breathing, viserosensory processing, vascular tone, and pain. Many hindbrain nuclei show a highly stereotyped pattern of localization across vertebrates suggesting a strong underlying genetic organization. Whether this is true for neurons within the reticular regions of hindbrain is unknown. Hindbrain neurons are derived from distinct developmental progenitor domains each of which expresses distinct patterns of transcription factors (TFs). These neuronal populations have distinct characteristics such as transmitter identity, migration, and connectivity suggesting developmentally expressed TFs might identify unique subpopulations of neurons within the reticular formation. A fate-mapping strategy using perinatal expression of reporter genes within Atoh1, Dbx1, Lmx1b, and Ptf1a transgenic mice coupled with immunohistochemistry (IHC) and in situ hybridization (ISH) were used to address the developmental organization of a large subset of reticular formation glutamatergic neurons. All hindbrain lineages have relatively large populations that extend the entire length of the hindbrain. Importantly, the location of neurons within each lineage was highly constrained. Lmx1b- and Dbx1- derived populations were both present in partially overlapping stripes within the reticular formation extending from dorsal to ventral brain. Within each lineage, distinct patterns of gene expression and organization were localized to specific hindbrain regions. Rostro-caudally sub-populations differ sequentially corresponding to proposed pseudo-rhombomereic boundaries. Dorsal-ventrally, sub-populations correspond to specific migratory positions. Together these data suggests the reticular formation is organized by a highly stereotyped developmental logic.

Swimming with multiple propulsors: measurement and comparison of swimming gaits in three species of neotropical cichlids.

PubMed

Feilich, Kara L

2017-11-15

Comparative studies of fish swimming have been limited by the lack of quantitative definitions of fish gaits. Traditionally, steady swimming gaits have been defined categorically by the fin or region of the body that is used as the main propulsor and named after major fish clades (e.g. carangiform, anguilliform, balistiform, labriform). This method of categorization is limited by the lack of explicit measurements, the inability to incorporate contributions of multiple propulsors and the inability to compare gaits across different categories. I propose an alternative framework for the definition and comparison of fish gaits based on the propulsive contribution of each structure (body and/or fin) being used as a propulsor relative to locomotor output, and demonstrate the effectiveness of this framework by comparing three species of neotropical cichlids with different body shapes. This approach is modular with respect to the number of propulsors considered, flexible with respect to the definition of the propulsive inputs and the locomotor output of interest, and designed explicitly to handle combinations of propulsors. Using this approach, gait can be defined as a trajectory through propulsive space, and gait transitions can be defined as discontinuities in the gait trajectory. By measuring and defining gait in this way, patterns of clustering corresponding to existing categorical definitions of gait may emerge, and gaits can be rigorously compared across categories. © 2017. Published by The Company of Biologists Ltd.

Fault and fracture patterns around a strike-slip influenced salt wall

NASA Astrophysics Data System (ADS)

Alsop, G. I.; Weinberger, R.; Marco, S.; Levi, T.

2018-01-01

The trends of faults and fractures in overburden next to a salt diapir are generally considered to be either parallel to the salt margin to form concentric patterns, or at right angles to the salt contact to create an overall radial distribution around the diapir. However, these simple diapir-related patterns may become more complex if regional tectonics influences the siting and growth of a diapir. Using the Sedom salt wall in the Dead Sea Fault system as our case study, we examine the influence of regional strike-slip faulting on fracture patterns around a salt diapir. This type of influence is important in general as the distribution and orientation of fractures on all scales may influence permeability and hence control fluid and hydrocarbon flow. Fractures adjacent to the N-S trending salt wall contain fibrous gypsum veins and injected clastic dykes, attesting to high fluid pressures adjacent to the diapir. Next to the western flank of the salt wall, broad (∼1000 m) zones of upturn or 'drape folds' are associated with NW-SE striking conjugate extensional fractures within the overburden. Within 300 m of the salt contact, fracture patterns in map view display a progressive ∼30°-35° clockwise rotation with more NNW-SSE strikes immediately adjacent to the salt wall. While some extensional faults display growth geometries, indicating that they were syn-depositional and initiated prior to tilting of beds associated with drape folding, other fractures display increasing dips towards the salt, suggesting that they have formed during upturn of bedding near the diapir. These observations collectively suggest that many fractures developed to accommodate rotation of beds during drape folding. Extensional fractures in the overburden define a mean strike that is ∼45° anticlockwise (counter-clockwise) of the N-S trending salt wall, and are therefore consistent with sinistral transtension along the N-S trending Sedom Fault that underlies the salt wall. Our outcrop analysis reveals fracture geometries that are related to both tilting of beds during drape folding, and regional strike-slip tectonics. The presence of faults and fractures that interact with drape folds suggests that deformation in overburden next to salt cannot be simply pigeon-holed into 'end-member' scenarios of purely brittle faulting or viscous flow.

Detection of Aberrant Response Patterns and Their Effect on Dimensionality.

ERIC Educational Resources Information Center

Tatsuoka, Kikumi K.; Tatsuoka, Maurice M.

An index measuring the degree to which a binary response pattern conforms to some baseline pattern was defined and named the Pattern Conformity Index (PCI). One way of conceptualizing what the PCI measures is the extent to which each individual's particular response pattern contributes to, or detracts from, the overall consistency found in the…

Transparent Flexible Electronics By Directed Integration of Inorganic Micro and Nanomaterials

NASA Astrophysics Data System (ADS)

Cole, Jesse J.

This thesis focuses on nanomanufacturing processes for the heterogeneous integration of nanomaterials. Our approaches involved local adjustment of electrostatics at the surfaces to control material flux. Templating of surface electrostatics was implemented differently for three broad concepts resulting in control over nanomaterial synthesis, deposition, and printing. These three general concepts are: (A) Tailored ZnO nanowire synthesis and integration out of the liquid phase; (B) Arc discharge synthesis and continuous nanocluster deposition from the gas phase; (C) Contact electrification and xerographic printing of nanoparticles from the gas phase. Concept (A): We report a method to fabricate and transfer crystalline ZnO with control over location, orientation, size, and shape. The process uses an oxygen plasma treatment in combination with a photoresist pattern on Magnesium-doped GaN substrates to define narrow nucleation regions and attachment points with 100 nanometer scale dimensions. Lateral epitaxial overgrowth follows nucleation to produce single crystalline ZnO which were fabricated into LEDs and photovoltaic cells. Concept (B): We report a gas phase nanoparticle deposition system which shares characteristics with liquid phase electrodeposition. Clusters of charged nanoparticles selectively deposit onto electrically grounded surfaces. Similar to electroplating, the continued deposition of Au nanoparticles onto underlying resistive traces increased overall line conductivity. Alternatively, semiconducting ZnO and Ge nanomaterial sequentially deposited between interdigitated electrodes and served as addressable sensor active areas. Concept (C): We report patterned transfer of charge between conformal material interfaces through a concept referred to as nanocontact electrification. Nanocontacts of different size and shape are formed between surface functionalized polydimethylsiloxane (PDMS) stamps and other dielectric materials (PMMA, SiO 2). Forced delamination and cleavage of the interface yields a well defined charge pattern with a minimal feature size of 100 nm. The process produces charged surfaces and associated fields that exceed the breakdown strength of air leading to strong long range adhesive forces and force distance curves which are recorded over macroscopic distances. The process is applied to fabricate charge patterned surfaces for nanoxerography demonstrating 200 nm resolution nanoparticle prints and applied to thin film electronics where the patterned charges are used to shift the threshold voltages of underlying transistors by over 500 mV.

Development of a robust reverse tone pattern transfer process

NASA Astrophysics Data System (ADS)

Khusnatdinov, Niyaz; Doyle, Gary; Resnick, Douglas J.; Ye, Zhengmao; LaBrake, Dwayne; Milligan, Brennan; Alokozai, Fred; Chen, Jerry

2017-03-01

Pattern transfer is critical to any lithographic technology, and plays a significant role in defining the critical features in a device layer. As both the memory and logic roadmaps continue to advance, greater importance is placed on the scheme used to do the etching. For many critical layers, a need has developed which requires a multilayer stack to be defined in order to perform the pattern transfer. There are many cases however, where this standard approach does not provide the best results in terms of critical dimension (CD) fidelity and CD uniformity. As an example, when defining a contact pattern, it may be advantageous to apply a bright field mask (in order to maximize the normalized inverse log slope (NILS)) over the more conventional dark field mask. The result of applying the bright field mask in combination with positive imaging resist is to define an array of pillar patterns, which then must be converted back to holes before etching the underlying dielectric material. There have been several publications on tone reversal that is introduced in the resist process itself, but often an etch transfer process is applied to reverse the pattern tone. The purpose of this paper is to describe the use of a three layer reverse tone process (RTP) that is capable of reversing the tone of every printed feature type. The process utilizes a resist pattern, a hardmask layer and an additional protection layer. The three layer approach overcomes issues encountered when using a single masking layer. Successful tone reversal was demonstrated both on 300mm wafers and imprint masks, including the largest features in the pattern, with dimensions as great as 60 microns. Initial in-field CD uniformity is promising. CDs shifted by about 2.6nm and no change was observed in either LER or LWR. Follow-up work is required to statistically qualify in-field CDU and also understand both across wafer uniformity and feature linearity.

Strong influence of variable treatment on the performance of numerically defined ecological regions.

PubMed

Snelder, Ton; Lehmann, Anthony; Lamouroux, Nicolas; Leathwick, John; Allenbach, Karin

2009-10-01

Numerical clustering has frequently been used to define hierarchically organized ecological regionalizations, but there has been little robust evaluation of their performance (i.e., the degree to which regions discriminate areas with similar ecological character). In this study we investigated the effect of the weighting and treatment of input variables on the performance of regionalizations defined by agglomerative clustering across a range of hierarchical levels. For this purpose, we developed three ecological regionalizations of Switzerland of increasing complexity using agglomerative clustering. Environmental data for our analysis were drawn from a 400 m grid and consisted of estimates of 11 environmental variables for each grid cell describing climate, topography and lithology. Regionalization 1 was defined from the environmental variables which were given equal weights. We used the same variables in Regionalization 2 but weighted and transformed them on the basis of a dissimilarity model that was fitted to land cover composition data derived for a random sample of cells from interpretation of aerial photographs. Regionalization 3 was a further two-stage development of Regionalization 2 where specific classifications, also weighted and transformed using dissimilarity models, were applied to 25 small scale "sub-domains" defined by Regionalization 2. Performance was assessed in terms of the discrimination of land cover composition for an independent set of sites using classification strength (CS), which measured the similarity of land cover composition within classes and the dissimilarity between classes. Regionalization 2 performed significantly better than Regionalization 1, but the largest gains in performance, compared to Regionalization 1, occurred at coarse hierarchical levels (i.e., CS did not increase significantly beyond the 25-region level). Regionalization 3 performed better than Regionalization 2 beyond the 25-region level and CS values continued to increase to the 95-region level. The results show that the performance of regionalizations defined by agglomerative clustering are sensitive to variable weighting and transformation. We conclude that large gains in performance can be achieved by training classifications using dissimilarity models. However, these gains are restricted to a narrow range of hierarchical levels because agglomerative clustering is unable to represent the variation in importance of variables at different spatial scales. We suggest that further advances in the numerical definition of hierarchically organized ecological regionalizations will be possible with techniques developed in the field of statistical modeling of the distribution of community composition.

Species pool, human population, and global versus regional invasion patterns

Treesearch

Qinfeng Guo; Basil V. Iannone III; Gabriela C. Nunez-Mir; Kevin M. Potter; Christopher M. Oswalt; Songlin Fei

2017-01-01

Context Biological invasions are among the greatest global and regional threats to biomes in the Anthropocene. Islands, in particular, have been perceived to have higher vulnerability to invasions. Because of the dynamic nature of ongoing invasions, distinguishing regional patterns from global patterns and their underlying determinants remains a challenge. Objectives...